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000
FXUS61 KCTP 210446
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1146 PM EST SAT DEC 20 2014

.SYNOPSIS...
AN AMPLIFYING UPPER RIDGE WILL MOVE INTO THE REGION ON
SUNDAY. TEMPERATURES WILL THEN BECOME JUST SLIGHTLY MILDER BUT
UNSETTLED CONDITIONS WILL BEGIN ON MONDAY NIGHT AND PREVAIL
THROUGH MID WEEK. A VIGOROUS STORM SYSTEM WILL SWEEP ACROSS THE
COMMONWEALTH ON CHRISTMAS EVE BRINGING WIDESPREAD SHOWERS AND A
CHANCE FOR THUNDERSTORMS. WINDY AND COLDER CONDITIONS WILL FOLLOW
WITH SCATTERED SNOW SHOWERS ACROSS THE WEST AND NORTH FOR
CHRISTMAS DAY. MILDER CONDITIONS WILL RETURN LATE THIS WEEK.

&&

.NEAR TERM /UNTIL 8 AM SUNDAY MORNING/...
CLOUDS COVERING ALL OF THE AREA AS A VIGOROUS SHORT WAVE ROLLS
OVERHEAD EARLY TONIGHT. ENOUGH LIFT PRESENT TO MAKE SOME ICE
CRYSTALS FALL OUT OF THE MID DECK AND SEED THE LOWER CLOUDS.
THUS...SOME FLURRIES ARE EXPECTED MAINLY EARLY TONIGHT OVER THE
LAURELS AND ALL NIGHT ALONG THE NRN TIER. WILL LEAVE ACCUMS OUT
OF THE FCST...BUT THE LIGHTEST OF DUSTINGS IS POSSIBLE. MINS
PROBABLY A HOMOGENEOUS 20-25F ACROSS THE BOARD.

&&

.SHORT TERM /8 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
DEEP LAYER DRYING BEHIND A DEPARTING 5H WAVE AND UPPER LEVEL
RIDGING HAS THE POTENTIAL TO BRING SUNSHINE TO MOST IF NOT ALL OF
CENTRAL PA ON MONDAY. THE STUBBORN STRATUS THAT HAS PLAGUED US FOR
MORE THAN A WEEK WILL HAVE A CHANCE TO MIX OUT...BUT TRANSITORY
SFC HIGH PRESSURE MAY STILL MAKE THIS A SLOW PROCESS OVER THE
NORTH.

PRIOR TO THAT...SOME AREAS COULD PERHAPS SEE A FLURRY IN THE PRE
DAWN HOURS SUNDAY BEFORE THE WAVE QUICKLY EXITS EASTWARD. WENT
CLOSE TO CONSALL GUIDANCE AGAIN WITH MAXES REACHING THE MID TO
UPPER 30S NORTH TO THE LOWER 40S SOUTH.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
THE MOST SIGNIFICANT FORECAST ISSUE IN THE LONG TERM IS THE
EVOLUTION OF THE MASSIVE CYCLONE TO OUR WEST 23-25 DECEMBER.
STRONG SOUTHERLY FLOW AHEAD OF THIS SYSTEM WILL BRING WARM AIR
INTO THE REGION LATE MONDAY INTO TUESDAY. BY TUESDAY AND WEDNESDAY
MANY LOW- LEVEL TEMPERATURE AND MOISTURE FIELDS WILL BE WELL ABOVE
THEIR SEASONAL VALUES. THIS IMPLIES VERY WARM WEATHER TUESDAY AND
WEDNESDAY...WHEN THE SHALLOW COLD AIR SCOURS OUT EAST OF THE
MOUNTAINS.

A COLD FRONT WITH STRONG WINDS WILL PRODUCE COLDER
CONDITIONS...LIKELY LATE CHRISTMAS EVE INTO CHRISTMAS DAY. THERE
WILL BE STRONG WESTERLY WINDS AND STRONG WIND GUSTS. SNOW SHOWERS
ARE LIKELY BEHIND THE SYSTEM IN WESTERN AREAS.

THE CHANGEABLE DETAILS...MONDAY THE ENSEMBLE FORECAST SHOWS A
WAVE PASSING TO OUR SOUTH WHICH COULD PRODUCE LIGHT SNOW OR A
MIX...MAINLY IN SOUTHEASTERN AREAS. THE IMPLIED LOW-LEVEL BOUNDARY
IS THE RETREATING COLD AIR TO OUR NORTHEAST AS THE STRONG CYCLONE
TO OUR WEST BEGINS TO TAKE SHAPE. IMPLIED LOW-LEVEL AGEOSTROPHIC
NORTHERLY FLOW HOLDING LOW-LEVEL COLD AIR IN MONDAY INTO TUESDAY.

TUESDAY THE COLD AIR SHOULD CONTINUE TO ERODE. HAD TO KEEP SOME
FREEZE RAIN/DRIZZLE IN NORTHEASTERN AREAS OVERNIGHT MONDAY INTO
TUESDAY BASED ON IMPLIED AGEOSTROPHIC FLOW AND ENSEMBLE
PRECIPITATION TYPES. BUT DURING THE DAY TUESDAY THE WARM AIR
SHOULD WIN OUT. THOUGH ALL SYSTEMS SHOW SOME HINTS OF COLD AIR
DAMMING....DAYTIME HIGHS EAST/NORTHEAST AREAS WILL BE WELL BELOW
WHAT ONE MIGHT EXPECT WITH 6-10C 850 MB TEMPS.

ANY PRECIPITATION TUESDAY AND WEDNESDAY SHOULD BE RAIN MUCH AFTER
NOON TUESDAY IN THE NORTHEAST. PRECIPITATION ON TUESDAY SHOULD BE
LIGHT...ENSEMBLES SHOW PROBABILITIES IN THE 20-30 RANGE AND LIGHT
AMOUNTS. THE PATTERN...SHARP NORTH-SOUTH FRONT TO OUR
WEST...IMPLIES SOME ISOLATED SHOWERS BUT THE MAIN RAIN EVENT
SHOULD WITHIN 3-6 HOURS OF THE FRONT.

TUESDAY THE STRONG CYCLONE...WITH SOME OF THE LOWEST SURFACE
PRESSURES IN THE EASTERN US ON 24 DECEMBER IN THE PAST 30 YEARS
WILL MOVE INTO THE GREAT LAKES. PRESSURE ANOMALIES ARE -3 TO -4
SIGMA BELOW NORMAL WITH A RETURN PERIOD ON THE ORDER OF 30 YEARS
IN SOME FORECAST SYSTEMS.

THE FRONT ASSOCIATED WITH THE CYCLONE PUSHES INTO OUR REGION
WEDNESDAY...AT THIS TIME THE 850 MB SOUTHERLY WINDS ARE FORECAST
TO BE ABOUT +3 SIGMA ABOVE NORMAL. THE STRONG SOUTHERLY FLOW...THE
HIGH PRECIPITABLE WATER...THE STRONG FRONT ALL IMPLY A FRONTAL
RAIN EVENT AND PERHAPS SOME RARE LATE DECEMBER (ELEVATED)
CONVECTION. IF THIS WERE AUTUMN OR SPRING WE MIGHT BE THINKING
QLCS. BUT SURFACE CAPE IS VIRTUALLY NON-EXISTENT BUT SHOWERY RAIN
AND PERHAPS ISOLATED THUNDER POSSIBLE.

DO NOT LIKE HAVING POPS ABOVE 60 TO 66 PERCENT AT DAY 5 IN 12 HOUR
PERIODS. TIMING WILL CLEARLY CHANGE BUT HAVE HIGH POPS FOR
CONSISTENCY WITH OTHER OFFICES.

CHRISTMAS EVE AND EARLY CHRISTMAS IS THE AREA OF HIGH UNCERTAINTY
AS TO WHEN THE COLD AIR COMES IN. THIS WILL DICTATE WHEN THE RAIN
COMES AND WHEN THE GUSTY WINDS SET IN. GRADIENTS ARE WHERE
FORECASTS ARE THEIR POOREST. BUT BY CHRISTMAS MORNING MOST IF NOT
ALL OF THE REGION SHOULD BE BELOW 0C AT 850 AND THE STRONG
WESTERLY WINDS SHOULD BE MIXING DOWN BEHIND THE FRONTAL BOUNDARY.
WINDY OVERNIGHT CHRISTMAS EVE INTO CHRISTMAS DAY. ANY RESIDUAL
PRECIPITATION SHOULD BE SNOW/SNOW SHOWERS AND FLURRIES.

TEMPERATURES SHOULD REBOUND FRIDAY AHEAD OF ANOTHER NORTHERN STREAM
WAVE MOVING INTO THE MID-WEST. THIS SHOULD RAISE OUR HEIGHTS AND
TEMPERATURES FRIDAY INTO EARLY SATURDAY. IT APPEARS A SERIES OF
WAVES MAY EVENTUALLY CARVE OUT A TROUGH OVER THE EAST-CENTRAL US. IF
SO...WE COULD END DECEMBER A BIT ON THE CHILLY SIDE.

&&

.AVIATION /04Z SUNDAY THROUGH THURSDAY/...
A WEAK AND SHALLOW STRATOCU DECK REMAINS TRAPPED BENEATH
SUBSIDENCE. THE CIG RESTRICTIONS WILL SPREAD AND INCREASE DUE TO
THE STRENGTHENING OF THE INVERSION OVERNIGHT...THOUGH LOW CLOUDS
SHOULD NOT BE QUITE AS EXPANSIVE AS PREVIOUS NIGHTS. A SHORTWAVE
WILL TRACK ACROSS THE REGION BRINGING A THICKENING MID- LVL DECK
AS WELL. THAT MID DECK WILL DECREASE THE PROBABILITY FOR A THICKER
LOW DECK. THE SURFACE WINDS WILL CONTINUE TO BE LIGHT...WITH SW
FLOW ALOFT BEGINNING TO INCREASE AS A LARGE LOW PRESSURE SYSTEM
BEGINS TO DEEPEN OVER THE CENTRAL U.S. EXPECT MVFR CIGS AT THE
CENTRAL SITES AOO...JST AND UNV. IFR REMAINS POSSIBLE AT JST
BETWEEN 09 TO 13Z...AND BFD SHOULD BE IFR THROUGH MOST OF THE
PERIOD. MAINLY VFR THROUGH THE EASTERN TAF SITES.
 BFD SHOULD LIFT TO MVFR BY LATE TOMORROW MORNING...THOUGH MVFR
SHOULD REMAIN POSSIBLE AT BFD THROUGH TOMORROW...AND IFR RETURNING
AT BFD TOMORROW EVENING.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

THU...WINDY AND COLDER WITH SCT MVFR CIGS AND -SHSN.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DEVOIR
LONG TERM...GRUMM
AVIATION...DEVOIR/CERU




000
FXUS61 KCTP 210446
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1146 PM EST SAT DEC 20 2014

.SYNOPSIS...
AN AMPLIFYING UPPER RIDGE WILL MOVE INTO THE REGION ON
SUNDAY. TEMPERATURES WILL THEN BECOME JUST SLIGHTLY MILDER BUT
UNSETTLED CONDITIONS WILL BEGIN ON MONDAY NIGHT AND PREVAIL
THROUGH MID WEEK. A VIGOROUS STORM SYSTEM WILL SWEEP ACROSS THE
COMMONWEALTH ON CHRISTMAS EVE BRINGING WIDESPREAD SHOWERS AND A
CHANCE FOR THUNDERSTORMS. WINDY AND COLDER CONDITIONS WILL FOLLOW
WITH SCATTERED SNOW SHOWERS ACROSS THE WEST AND NORTH FOR
CHRISTMAS DAY. MILDER CONDITIONS WILL RETURN LATE THIS WEEK.

&&

.NEAR TERM /UNTIL 8 AM SUNDAY MORNING/...
CLOUDS COVERING ALL OF THE AREA AS A VIGOROUS SHORT WAVE ROLLS
OVERHEAD EARLY TONIGHT. ENOUGH LIFT PRESENT TO MAKE SOME ICE
CRYSTALS FALL OUT OF THE MID DECK AND SEED THE LOWER CLOUDS.
THUS...SOME FLURRIES ARE EXPECTED MAINLY EARLY TONIGHT OVER THE
LAURELS AND ALL NIGHT ALONG THE NRN TIER. WILL LEAVE ACCUMS OUT
OF THE FCST...BUT THE LIGHTEST OF DUSTINGS IS POSSIBLE. MINS
PROBABLY A HOMOGENEOUS 20-25F ACROSS THE BOARD.

&&

.SHORT TERM /8 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
DEEP LAYER DRYING BEHIND A DEPARTING 5H WAVE AND UPPER LEVEL
RIDGING HAS THE POTENTIAL TO BRING SUNSHINE TO MOST IF NOT ALL OF
CENTRAL PA ON MONDAY. THE STUBBORN STRATUS THAT HAS PLAGUED US FOR
MORE THAN A WEEK WILL HAVE A CHANCE TO MIX OUT...BUT TRANSITORY
SFC HIGH PRESSURE MAY STILL MAKE THIS A SLOW PROCESS OVER THE
NORTH.

PRIOR TO THAT...SOME AREAS COULD PERHAPS SEE A FLURRY IN THE PRE
DAWN HOURS SUNDAY BEFORE THE WAVE QUICKLY EXITS EASTWARD. WENT
CLOSE TO CONSALL GUIDANCE AGAIN WITH MAXES REACHING THE MID TO
UPPER 30S NORTH TO THE LOWER 40S SOUTH.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
THE MOST SIGNIFICANT FORECAST ISSUE IN THE LONG TERM IS THE
EVOLUTION OF THE MASSIVE CYCLONE TO OUR WEST 23-25 DECEMBER.
STRONG SOUTHERLY FLOW AHEAD OF THIS SYSTEM WILL BRING WARM AIR
INTO THE REGION LATE MONDAY INTO TUESDAY. BY TUESDAY AND WEDNESDAY
MANY LOW- LEVEL TEMPERATURE AND MOISTURE FIELDS WILL BE WELL ABOVE
THEIR SEASONAL VALUES. THIS IMPLIES VERY WARM WEATHER TUESDAY AND
WEDNESDAY...WHEN THE SHALLOW COLD AIR SCOURS OUT EAST OF THE
MOUNTAINS.

A COLD FRONT WITH STRONG WINDS WILL PRODUCE COLDER
CONDITIONS...LIKELY LATE CHRISTMAS EVE INTO CHRISTMAS DAY. THERE
WILL BE STRONG WESTERLY WINDS AND STRONG WIND GUSTS. SNOW SHOWERS
ARE LIKELY BEHIND THE SYSTEM IN WESTERN AREAS.

THE CHANGEABLE DETAILS...MONDAY THE ENSEMBLE FORECAST SHOWS A
WAVE PASSING TO OUR SOUTH WHICH COULD PRODUCE LIGHT SNOW OR A
MIX...MAINLY IN SOUTHEASTERN AREAS. THE IMPLIED LOW-LEVEL BOUNDARY
IS THE RETREATING COLD AIR TO OUR NORTHEAST AS THE STRONG CYCLONE
TO OUR WEST BEGINS TO TAKE SHAPE. IMPLIED LOW-LEVEL AGEOSTROPHIC
NORTHERLY FLOW HOLDING LOW-LEVEL COLD AIR IN MONDAY INTO TUESDAY.

TUESDAY THE COLD AIR SHOULD CONTINUE TO ERODE. HAD TO KEEP SOME
FREEZE RAIN/DRIZZLE IN NORTHEASTERN AREAS OVERNIGHT MONDAY INTO
TUESDAY BASED ON IMPLIED AGEOSTROPHIC FLOW AND ENSEMBLE
PRECIPITATION TYPES. BUT DURING THE DAY TUESDAY THE WARM AIR
SHOULD WIN OUT. THOUGH ALL SYSTEMS SHOW SOME HINTS OF COLD AIR
DAMMING....DAYTIME HIGHS EAST/NORTHEAST AREAS WILL BE WELL BELOW
WHAT ONE MIGHT EXPECT WITH 6-10C 850 MB TEMPS.

ANY PRECIPITATION TUESDAY AND WEDNESDAY SHOULD BE RAIN MUCH AFTER
NOON TUESDAY IN THE NORTHEAST. PRECIPITATION ON TUESDAY SHOULD BE
LIGHT...ENSEMBLES SHOW PROBABILITIES IN THE 20-30 RANGE AND LIGHT
AMOUNTS. THE PATTERN...SHARP NORTH-SOUTH FRONT TO OUR
WEST...IMPLIES SOME ISOLATED SHOWERS BUT THE MAIN RAIN EVENT
SHOULD WITHIN 3-6 HOURS OF THE FRONT.

TUESDAY THE STRONG CYCLONE...WITH SOME OF THE LOWEST SURFACE
PRESSURES IN THE EASTERN US ON 24 DECEMBER IN THE PAST 30 YEARS
WILL MOVE INTO THE GREAT LAKES. PRESSURE ANOMALIES ARE -3 TO -4
SIGMA BELOW NORMAL WITH A RETURN PERIOD ON THE ORDER OF 30 YEARS
IN SOME FORECAST SYSTEMS.

THE FRONT ASSOCIATED WITH THE CYCLONE PUSHES INTO OUR REGION
WEDNESDAY...AT THIS TIME THE 850 MB SOUTHERLY WINDS ARE FORECAST
TO BE ABOUT +3 SIGMA ABOVE NORMAL. THE STRONG SOUTHERLY FLOW...THE
HIGH PRECIPITABLE WATER...THE STRONG FRONT ALL IMPLY A FRONTAL
RAIN EVENT AND PERHAPS SOME RARE LATE DECEMBER (ELEVATED)
CONVECTION. IF THIS WERE AUTUMN OR SPRING WE MIGHT BE THINKING
QLCS. BUT SURFACE CAPE IS VIRTUALLY NON-EXISTENT BUT SHOWERY RAIN
AND PERHAPS ISOLATED THUNDER POSSIBLE.

DO NOT LIKE HAVING POPS ABOVE 60 TO 66 PERCENT AT DAY 5 IN 12 HOUR
PERIODS. TIMING WILL CLEARLY CHANGE BUT HAVE HIGH POPS FOR
CONSISTENCY WITH OTHER OFFICES.

CHRISTMAS EVE AND EARLY CHRISTMAS IS THE AREA OF HIGH UNCERTAINTY
AS TO WHEN THE COLD AIR COMES IN. THIS WILL DICTATE WHEN THE RAIN
COMES AND WHEN THE GUSTY WINDS SET IN. GRADIENTS ARE WHERE
FORECASTS ARE THEIR POOREST. BUT BY CHRISTMAS MORNING MOST IF NOT
ALL OF THE REGION SHOULD BE BELOW 0C AT 850 AND THE STRONG
WESTERLY WINDS SHOULD BE MIXING DOWN BEHIND THE FRONTAL BOUNDARY.
WINDY OVERNIGHT CHRISTMAS EVE INTO CHRISTMAS DAY. ANY RESIDUAL
PRECIPITATION SHOULD BE SNOW/SNOW SHOWERS AND FLURRIES.

TEMPERATURES SHOULD REBOUND FRIDAY AHEAD OF ANOTHER NORTHERN STREAM
WAVE MOVING INTO THE MID-WEST. THIS SHOULD RAISE OUR HEIGHTS AND
TEMPERATURES FRIDAY INTO EARLY SATURDAY. IT APPEARS A SERIES OF
WAVES MAY EVENTUALLY CARVE OUT A TROUGH OVER THE EAST-CENTRAL US. IF
SO...WE COULD END DECEMBER A BIT ON THE CHILLY SIDE.

&&

.AVIATION /04Z SUNDAY THROUGH THURSDAY/...
A WEAK AND SHALLOW STRATOCU DECK REMAINS TRAPPED BENEATH
SUBSIDENCE. THE CIG RESTRICTIONS WILL SPREAD AND INCREASE DUE TO
THE STRENGTHENING OF THE INVERSION OVERNIGHT...THOUGH LOW CLOUDS
SHOULD NOT BE QUITE AS EXPANSIVE AS PREVIOUS NIGHTS. A SHORTWAVE
WILL TRACK ACROSS THE REGION BRINGING A THICKENING MID- LVL DECK
AS WELL. THAT MID DECK WILL DECREASE THE PROBABILITY FOR A THICKER
LOW DECK. THE SURFACE WINDS WILL CONTINUE TO BE LIGHT...WITH SW
FLOW ALOFT BEGINNING TO INCREASE AS A LARGE LOW PRESSURE SYSTEM
BEGINS TO DEEPEN OVER THE CENTRAL U.S. EXPECT MVFR CIGS AT THE
CENTRAL SITES AOO...JST AND UNV. IFR REMAINS POSSIBLE AT JST
BETWEEN 09 TO 13Z...AND BFD SHOULD BE IFR THROUGH MOST OF THE
PERIOD. MAINLY VFR THROUGH THE EASTERN TAF SITES.
 BFD SHOULD LIFT TO MVFR BY LATE TOMORROW MORNING...THOUGH MVFR
SHOULD REMAIN POSSIBLE AT BFD THROUGH TOMORROW...AND IFR RETURNING
AT BFD TOMORROW EVENING.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

THU...WINDY AND COLDER WITH SCT MVFR CIGS AND -SHSN.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DEVOIR
LONG TERM...GRUMM
AVIATION...DEVOIR/CERU




000
FXUS61 KCTP 210446
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1146 PM EST SAT DEC 20 2014

.SYNOPSIS...
AN AMPLIFYING UPPER RIDGE WILL MOVE INTO THE REGION ON
SUNDAY. TEMPERATURES WILL THEN BECOME JUST SLIGHTLY MILDER BUT
UNSETTLED CONDITIONS WILL BEGIN ON MONDAY NIGHT AND PREVAIL
THROUGH MID WEEK. A VIGOROUS STORM SYSTEM WILL SWEEP ACROSS THE
COMMONWEALTH ON CHRISTMAS EVE BRINGING WIDESPREAD SHOWERS AND A
CHANCE FOR THUNDERSTORMS. WINDY AND COLDER CONDITIONS WILL FOLLOW
WITH SCATTERED SNOW SHOWERS ACROSS THE WEST AND NORTH FOR
CHRISTMAS DAY. MILDER CONDITIONS WILL RETURN LATE THIS WEEK.

&&

.NEAR TERM /UNTIL 8 AM SUNDAY MORNING/...
CLOUDS COVERING ALL OF THE AREA AS A VIGOROUS SHORT WAVE ROLLS
OVERHEAD EARLY TONIGHT. ENOUGH LIFT PRESENT TO MAKE SOME ICE
CRYSTALS FALL OUT OF THE MID DECK AND SEED THE LOWER CLOUDS.
THUS...SOME FLURRIES ARE EXPECTED MAINLY EARLY TONIGHT OVER THE
LAURELS AND ALL NIGHT ALONG THE NRN TIER. WILL LEAVE ACCUMS OUT
OF THE FCST...BUT THE LIGHTEST OF DUSTINGS IS POSSIBLE. MINS
PROBABLY A HOMOGENEOUS 20-25F ACROSS THE BOARD.

&&

.SHORT TERM /8 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
DEEP LAYER DRYING BEHIND A DEPARTING 5H WAVE AND UPPER LEVEL
RIDGING HAS THE POTENTIAL TO BRING SUNSHINE TO MOST IF NOT ALL OF
CENTRAL PA ON MONDAY. THE STUBBORN STRATUS THAT HAS PLAGUED US FOR
MORE THAN A WEEK WILL HAVE A CHANCE TO MIX OUT...BUT TRANSITORY
SFC HIGH PRESSURE MAY STILL MAKE THIS A SLOW PROCESS OVER THE
NORTH.

PRIOR TO THAT...SOME AREAS COULD PERHAPS SEE A FLURRY IN THE PRE
DAWN HOURS SUNDAY BEFORE THE WAVE QUICKLY EXITS EASTWARD. WENT
CLOSE TO CONSALL GUIDANCE AGAIN WITH MAXES REACHING THE MID TO
UPPER 30S NORTH TO THE LOWER 40S SOUTH.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
THE MOST SIGNIFICANT FORECAST ISSUE IN THE LONG TERM IS THE
EVOLUTION OF THE MASSIVE CYCLONE TO OUR WEST 23-25 DECEMBER.
STRONG SOUTHERLY FLOW AHEAD OF THIS SYSTEM WILL BRING WARM AIR
INTO THE REGION LATE MONDAY INTO TUESDAY. BY TUESDAY AND WEDNESDAY
MANY LOW- LEVEL TEMPERATURE AND MOISTURE FIELDS WILL BE WELL ABOVE
THEIR SEASONAL VALUES. THIS IMPLIES VERY WARM WEATHER TUESDAY AND
WEDNESDAY...WHEN THE SHALLOW COLD AIR SCOURS OUT EAST OF THE
MOUNTAINS.

A COLD FRONT WITH STRONG WINDS WILL PRODUCE COLDER
CONDITIONS...LIKELY LATE CHRISTMAS EVE INTO CHRISTMAS DAY. THERE
WILL BE STRONG WESTERLY WINDS AND STRONG WIND GUSTS. SNOW SHOWERS
ARE LIKELY BEHIND THE SYSTEM IN WESTERN AREAS.

THE CHANGEABLE DETAILS...MONDAY THE ENSEMBLE FORECAST SHOWS A
WAVE PASSING TO OUR SOUTH WHICH COULD PRODUCE LIGHT SNOW OR A
MIX...MAINLY IN SOUTHEASTERN AREAS. THE IMPLIED LOW-LEVEL BOUNDARY
IS THE RETREATING COLD AIR TO OUR NORTHEAST AS THE STRONG CYCLONE
TO OUR WEST BEGINS TO TAKE SHAPE. IMPLIED LOW-LEVEL AGEOSTROPHIC
NORTHERLY FLOW HOLDING LOW-LEVEL COLD AIR IN MONDAY INTO TUESDAY.

TUESDAY THE COLD AIR SHOULD CONTINUE TO ERODE. HAD TO KEEP SOME
FREEZE RAIN/DRIZZLE IN NORTHEASTERN AREAS OVERNIGHT MONDAY INTO
TUESDAY BASED ON IMPLIED AGEOSTROPHIC FLOW AND ENSEMBLE
PRECIPITATION TYPES. BUT DURING THE DAY TUESDAY THE WARM AIR
SHOULD WIN OUT. THOUGH ALL SYSTEMS SHOW SOME HINTS OF COLD AIR
DAMMING....DAYTIME HIGHS EAST/NORTHEAST AREAS WILL BE WELL BELOW
WHAT ONE MIGHT EXPECT WITH 6-10C 850 MB TEMPS.

ANY PRECIPITATION TUESDAY AND WEDNESDAY SHOULD BE RAIN MUCH AFTER
NOON TUESDAY IN THE NORTHEAST. PRECIPITATION ON TUESDAY SHOULD BE
LIGHT...ENSEMBLES SHOW PROBABILITIES IN THE 20-30 RANGE AND LIGHT
AMOUNTS. THE PATTERN...SHARP NORTH-SOUTH FRONT TO OUR
WEST...IMPLIES SOME ISOLATED SHOWERS BUT THE MAIN RAIN EVENT
SHOULD WITHIN 3-6 HOURS OF THE FRONT.

TUESDAY THE STRONG CYCLONE...WITH SOME OF THE LOWEST SURFACE
PRESSURES IN THE EASTERN US ON 24 DECEMBER IN THE PAST 30 YEARS
WILL MOVE INTO THE GREAT LAKES. PRESSURE ANOMALIES ARE -3 TO -4
SIGMA BELOW NORMAL WITH A RETURN PERIOD ON THE ORDER OF 30 YEARS
IN SOME FORECAST SYSTEMS.

THE FRONT ASSOCIATED WITH THE CYCLONE PUSHES INTO OUR REGION
WEDNESDAY...AT THIS TIME THE 850 MB SOUTHERLY WINDS ARE FORECAST
TO BE ABOUT +3 SIGMA ABOVE NORMAL. THE STRONG SOUTHERLY FLOW...THE
HIGH PRECIPITABLE WATER...THE STRONG FRONT ALL IMPLY A FRONTAL
RAIN EVENT AND PERHAPS SOME RARE LATE DECEMBER (ELEVATED)
CONVECTION. IF THIS WERE AUTUMN OR SPRING WE MIGHT BE THINKING
QLCS. BUT SURFACE CAPE IS VIRTUALLY NON-EXISTENT BUT SHOWERY RAIN
AND PERHAPS ISOLATED THUNDER POSSIBLE.

DO NOT LIKE HAVING POPS ABOVE 60 TO 66 PERCENT AT DAY 5 IN 12 HOUR
PERIODS. TIMING WILL CLEARLY CHANGE BUT HAVE HIGH POPS FOR
CONSISTENCY WITH OTHER OFFICES.

CHRISTMAS EVE AND EARLY CHRISTMAS IS THE AREA OF HIGH UNCERTAINTY
AS TO WHEN THE COLD AIR COMES IN. THIS WILL DICTATE WHEN THE RAIN
COMES AND WHEN THE GUSTY WINDS SET IN. GRADIENTS ARE WHERE
FORECASTS ARE THEIR POOREST. BUT BY CHRISTMAS MORNING MOST IF NOT
ALL OF THE REGION SHOULD BE BELOW 0C AT 850 AND THE STRONG
WESTERLY WINDS SHOULD BE MIXING DOWN BEHIND THE FRONTAL BOUNDARY.
WINDY OVERNIGHT CHRISTMAS EVE INTO CHRISTMAS DAY. ANY RESIDUAL
PRECIPITATION SHOULD BE SNOW/SNOW SHOWERS AND FLURRIES.

TEMPERATURES SHOULD REBOUND FRIDAY AHEAD OF ANOTHER NORTHERN STREAM
WAVE MOVING INTO THE MID-WEST. THIS SHOULD RAISE OUR HEIGHTS AND
TEMPERATURES FRIDAY INTO EARLY SATURDAY. IT APPEARS A SERIES OF
WAVES MAY EVENTUALLY CARVE OUT A TROUGH OVER THE EAST-CENTRAL US. IF
SO...WE COULD END DECEMBER A BIT ON THE CHILLY SIDE.

&&

.AVIATION /04Z SUNDAY THROUGH THURSDAY/...
A WEAK AND SHALLOW STRATOCU DECK REMAINS TRAPPED BENEATH
SUBSIDENCE. THE CIG RESTRICTIONS WILL SPREAD AND INCREASE DUE TO
THE STRENGTHENING OF THE INVERSION OVERNIGHT...THOUGH LOW CLOUDS
SHOULD NOT BE QUITE AS EXPANSIVE AS PREVIOUS NIGHTS. A SHORTWAVE
WILL TRACK ACROSS THE REGION BRINGING A THICKENING MID- LVL DECK
AS WELL. THAT MID DECK WILL DECREASE THE PROBABILITY FOR A THICKER
LOW DECK. THE SURFACE WINDS WILL CONTINUE TO BE LIGHT...WITH SW
FLOW ALOFT BEGINNING TO INCREASE AS A LARGE LOW PRESSURE SYSTEM
BEGINS TO DEEPEN OVER THE CENTRAL U.S. EXPECT MVFR CIGS AT THE
CENTRAL SITES AOO...JST AND UNV. IFR REMAINS POSSIBLE AT JST
BETWEEN 09 TO 13Z...AND BFD SHOULD BE IFR THROUGH MOST OF THE
PERIOD. MAINLY VFR THROUGH THE EASTERN TAF SITES.
 BFD SHOULD LIFT TO MVFR BY LATE TOMORROW MORNING...THOUGH MVFR
SHOULD REMAIN POSSIBLE AT BFD THROUGH TOMORROW...AND IFR RETURNING
AT BFD TOMORROW EVENING.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

THU...WINDY AND COLDER WITH SCT MVFR CIGS AND -SHSN.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DEVOIR
LONG TERM...GRUMM
AVIATION...DEVOIR/CERU




000
FXUS61 KCTP 210446
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1146 PM EST SAT DEC 20 2014

.SYNOPSIS...
AN AMPLIFYING UPPER RIDGE WILL MOVE INTO THE REGION ON
SUNDAY. TEMPERATURES WILL THEN BECOME JUST SLIGHTLY MILDER BUT
UNSETTLED CONDITIONS WILL BEGIN ON MONDAY NIGHT AND PREVAIL
THROUGH MID WEEK. A VIGOROUS STORM SYSTEM WILL SWEEP ACROSS THE
COMMONWEALTH ON CHRISTMAS EVE BRINGING WIDESPREAD SHOWERS AND A
CHANCE FOR THUNDERSTORMS. WINDY AND COLDER CONDITIONS WILL FOLLOW
WITH SCATTERED SNOW SHOWERS ACROSS THE WEST AND NORTH FOR
CHRISTMAS DAY. MILDER CONDITIONS WILL RETURN LATE THIS WEEK.

&&

.NEAR TERM /UNTIL 8 AM SUNDAY MORNING/...
CLOUDS COVERING ALL OF THE AREA AS A VIGOROUS SHORT WAVE ROLLS
OVERHEAD EARLY TONIGHT. ENOUGH LIFT PRESENT TO MAKE SOME ICE
CRYSTALS FALL OUT OF THE MID DECK AND SEED THE LOWER CLOUDS.
THUS...SOME FLURRIES ARE EXPECTED MAINLY EARLY TONIGHT OVER THE
LAURELS AND ALL NIGHT ALONG THE NRN TIER. WILL LEAVE ACCUMS OUT
OF THE FCST...BUT THE LIGHTEST OF DUSTINGS IS POSSIBLE. MINS
PROBABLY A HOMOGENEOUS 20-25F ACROSS THE BOARD.

&&

.SHORT TERM /8 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
DEEP LAYER DRYING BEHIND A DEPARTING 5H WAVE AND UPPER LEVEL
RIDGING HAS THE POTENTIAL TO BRING SUNSHINE TO MOST IF NOT ALL OF
CENTRAL PA ON MONDAY. THE STUBBORN STRATUS THAT HAS PLAGUED US FOR
MORE THAN A WEEK WILL HAVE A CHANCE TO MIX OUT...BUT TRANSITORY
SFC HIGH PRESSURE MAY STILL MAKE THIS A SLOW PROCESS OVER THE
NORTH.

PRIOR TO THAT...SOME AREAS COULD PERHAPS SEE A FLURRY IN THE PRE
DAWN HOURS SUNDAY BEFORE THE WAVE QUICKLY EXITS EASTWARD. WENT
CLOSE TO CONSALL GUIDANCE AGAIN WITH MAXES REACHING THE MID TO
UPPER 30S NORTH TO THE LOWER 40S SOUTH.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
THE MOST SIGNIFICANT FORECAST ISSUE IN THE LONG TERM IS THE
EVOLUTION OF THE MASSIVE CYCLONE TO OUR WEST 23-25 DECEMBER.
STRONG SOUTHERLY FLOW AHEAD OF THIS SYSTEM WILL BRING WARM AIR
INTO THE REGION LATE MONDAY INTO TUESDAY. BY TUESDAY AND WEDNESDAY
MANY LOW- LEVEL TEMPERATURE AND MOISTURE FIELDS WILL BE WELL ABOVE
THEIR SEASONAL VALUES. THIS IMPLIES VERY WARM WEATHER TUESDAY AND
WEDNESDAY...WHEN THE SHALLOW COLD AIR SCOURS OUT EAST OF THE
MOUNTAINS.

A COLD FRONT WITH STRONG WINDS WILL PRODUCE COLDER
CONDITIONS...LIKELY LATE CHRISTMAS EVE INTO CHRISTMAS DAY. THERE
WILL BE STRONG WESTERLY WINDS AND STRONG WIND GUSTS. SNOW SHOWERS
ARE LIKELY BEHIND THE SYSTEM IN WESTERN AREAS.

THE CHANGEABLE DETAILS...MONDAY THE ENSEMBLE FORECAST SHOWS A
WAVE PASSING TO OUR SOUTH WHICH COULD PRODUCE LIGHT SNOW OR A
MIX...MAINLY IN SOUTHEASTERN AREAS. THE IMPLIED LOW-LEVEL BOUNDARY
IS THE RETREATING COLD AIR TO OUR NORTHEAST AS THE STRONG CYCLONE
TO OUR WEST BEGINS TO TAKE SHAPE. IMPLIED LOW-LEVEL AGEOSTROPHIC
NORTHERLY FLOW HOLDING LOW-LEVEL COLD AIR IN MONDAY INTO TUESDAY.

TUESDAY THE COLD AIR SHOULD CONTINUE TO ERODE. HAD TO KEEP SOME
FREEZE RAIN/DRIZZLE IN NORTHEASTERN AREAS OVERNIGHT MONDAY INTO
TUESDAY BASED ON IMPLIED AGEOSTROPHIC FLOW AND ENSEMBLE
PRECIPITATION TYPES. BUT DURING THE DAY TUESDAY THE WARM AIR
SHOULD WIN OUT. THOUGH ALL SYSTEMS SHOW SOME HINTS OF COLD AIR
DAMMING....DAYTIME HIGHS EAST/NORTHEAST AREAS WILL BE WELL BELOW
WHAT ONE MIGHT EXPECT WITH 6-10C 850 MB TEMPS.

ANY PRECIPITATION TUESDAY AND WEDNESDAY SHOULD BE RAIN MUCH AFTER
NOON TUESDAY IN THE NORTHEAST. PRECIPITATION ON TUESDAY SHOULD BE
LIGHT...ENSEMBLES SHOW PROBABILITIES IN THE 20-30 RANGE AND LIGHT
AMOUNTS. THE PATTERN...SHARP NORTH-SOUTH FRONT TO OUR
WEST...IMPLIES SOME ISOLATED SHOWERS BUT THE MAIN RAIN EVENT
SHOULD WITHIN 3-6 HOURS OF THE FRONT.

TUESDAY THE STRONG CYCLONE...WITH SOME OF THE LOWEST SURFACE
PRESSURES IN THE EASTERN US ON 24 DECEMBER IN THE PAST 30 YEARS
WILL MOVE INTO THE GREAT LAKES. PRESSURE ANOMALIES ARE -3 TO -4
SIGMA BELOW NORMAL WITH A RETURN PERIOD ON THE ORDER OF 30 YEARS
IN SOME FORECAST SYSTEMS.

THE FRONT ASSOCIATED WITH THE CYCLONE PUSHES INTO OUR REGION
WEDNESDAY...AT THIS TIME THE 850 MB SOUTHERLY WINDS ARE FORECAST
TO BE ABOUT +3 SIGMA ABOVE NORMAL. THE STRONG SOUTHERLY FLOW...THE
HIGH PRECIPITABLE WATER...THE STRONG FRONT ALL IMPLY A FRONTAL
RAIN EVENT AND PERHAPS SOME RARE LATE DECEMBER (ELEVATED)
CONVECTION. IF THIS WERE AUTUMN OR SPRING WE MIGHT BE THINKING
QLCS. BUT SURFACE CAPE IS VIRTUALLY NON-EXISTENT BUT SHOWERY RAIN
AND PERHAPS ISOLATED THUNDER POSSIBLE.

DO NOT LIKE HAVING POPS ABOVE 60 TO 66 PERCENT AT DAY 5 IN 12 HOUR
PERIODS. TIMING WILL CLEARLY CHANGE BUT HAVE HIGH POPS FOR
CONSISTENCY WITH OTHER OFFICES.

CHRISTMAS EVE AND EARLY CHRISTMAS IS THE AREA OF HIGH UNCERTAINTY
AS TO WHEN THE COLD AIR COMES IN. THIS WILL DICTATE WHEN THE RAIN
COMES AND WHEN THE GUSTY WINDS SET IN. GRADIENTS ARE WHERE
FORECASTS ARE THEIR POOREST. BUT BY CHRISTMAS MORNING MOST IF NOT
ALL OF THE REGION SHOULD BE BELOW 0C AT 850 AND THE STRONG
WESTERLY WINDS SHOULD BE MIXING DOWN BEHIND THE FRONTAL BOUNDARY.
WINDY OVERNIGHT CHRISTMAS EVE INTO CHRISTMAS DAY. ANY RESIDUAL
PRECIPITATION SHOULD BE SNOW/SNOW SHOWERS AND FLURRIES.

TEMPERATURES SHOULD REBOUND FRIDAY AHEAD OF ANOTHER NORTHERN STREAM
WAVE MOVING INTO THE MID-WEST. THIS SHOULD RAISE OUR HEIGHTS AND
TEMPERATURES FRIDAY INTO EARLY SATURDAY. IT APPEARS A SERIES OF
WAVES MAY EVENTUALLY CARVE OUT A TROUGH OVER THE EAST-CENTRAL US. IF
SO...WE COULD END DECEMBER A BIT ON THE CHILLY SIDE.

&&

.AVIATION /04Z SUNDAY THROUGH THURSDAY/...
A WEAK AND SHALLOW STRATOCU DECK REMAINS TRAPPED BENEATH
SUBSIDENCE. THE CIG RESTRICTIONS WILL SPREAD AND INCREASE DUE TO
THE STRENGTHENING OF THE INVERSION OVERNIGHT...THOUGH LOW CLOUDS
SHOULD NOT BE QUITE AS EXPANSIVE AS PREVIOUS NIGHTS. A SHORTWAVE
WILL TRACK ACROSS THE REGION BRINGING A THICKENING MID- LVL DECK
AS WELL. THAT MID DECK WILL DECREASE THE PROBABILITY FOR A THICKER
LOW DECK. THE SURFACE WINDS WILL CONTINUE TO BE LIGHT...WITH SW
FLOW ALOFT BEGINNING TO INCREASE AS A LARGE LOW PRESSURE SYSTEM
BEGINS TO DEEPEN OVER THE CENTRAL U.S. EXPECT MVFR CIGS AT THE
CENTRAL SITES AOO...JST AND UNV. IFR REMAINS POSSIBLE AT JST
BETWEEN 09 TO 13Z...AND BFD SHOULD BE IFR THROUGH MOST OF THE
PERIOD. MAINLY VFR THROUGH THE EASTERN TAF SITES.
 BFD SHOULD LIFT TO MVFR BY LATE TOMORROW MORNING...THOUGH MVFR
SHOULD REMAIN POSSIBLE AT BFD THROUGH TOMORROW...AND IFR RETURNING
AT BFD TOMORROW EVENING.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

THU...WINDY AND COLDER WITH SCT MVFR CIGS AND -SHSN.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DEVOIR
LONG TERM...GRUMM
AVIATION...DEVOIR/CERU




000
FXUS61 KCTP 210234
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
934 PM EST SAT DEC 20 2014

.SYNOPSIS...
AN AMPLIFYING UPPER RIDGE WILL MOVE INTO THE REGION ON
SUNDAY. TEMPERATURES WILL THEN BECOME JUST SLIGHTLY MILDER BUT
UNSETTLED CONDITIONS WILL BEGIN ON MONDAY NIGHT AND PREVAIL
THROUGH MID WEEK. A VIGOROUS STORM SYSTEM WILL SWEEP ACROSS THE
COMMONWEALTH ON CHRISTMAS EVE BRINGING WIDESPREAD SHOWERS AND A
CHANCE FOR THUNDERSTORMS. WINDY AND COLDER CONDITIONS WILL FOLLOW
WITH SCATTERED SNOW SHOWERS ACROSS THE WEST AND NORTH FOR
CHRISTMAS DAY. MILDER CONDITIONS WILL RETURN LATE THIS WEEK.

&&

.NEAR TERM /UNTIL 8 AM SUNDAY MORNING/...
CLOUDS COVERING ALL OF THE AREA AS A VIGOROUS SHORT WAVE ROLLS
OVERHEAD EARLY TONIGHT. ENOUGH LIFT PRESENT TO MAKE SOME ICE
CRYSTALS FALL OUT OF THE MID DECK AND SEED THE LOWER CLOUDS.
THUS...SOME FLURRIES ARE EXPECTED MAINLY EARLY TONIGHT OVER THE
LAURELS AND ALL NIGHT ALONG THE NRN TIER. WILL LEAVE ACCUMS OUT
OF THE FCST...BUT THE LIGHTEST OF DUSTINGS IS POSSIBLE. MINS
PROBABLY A HOMOGENEOUS 20-25F ACROSS THE BOARD.

&&

.SHORT TERM /8 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
DEEP LAYER DRYING BEHIND A DEPARTING 5H WAVE AND UPPER LEVEL
RIDGING HAS THE POTENTIAL TO BRING SUNSHINE TO MOST IF NOT ALL OF
CENTRAL PA ON MONDAY. THE STUBBORN STRATUS THAT HAS PLAGUED US FOR
MORE THAN A WEEK WILL HAVE A CHANCE TO MIX OUT...BUT TRANSITORY
SFC HIGH PRESSURE MAY STILL MAKE THIS A SLOW PROCESS OVER THE
NORTH.

PRIOR TO THAT...SOME AREAS COULD PERHAPS SEE A FLURRY IN THE PRE
DAWN HOURS SUNDAY BEFORE THE WAVE QUICKLY EXITS EASTWARD. WENT
CLOSE TO CONSALL GUIDANCE AGAIN WITH MAXES REACHING THE MID TO
UPPER 30S NORTH TO THE LOWER 40S SOUTH.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
THE MOST SIGNIFICANT FORECAST ISSUE IN THE LONG TERM IS THE
EVOLUTION OF THE MASSIVE CYCLONE TO OUR WEST 23-25 DECEMBER.
STRONG SOUTHERLY FLOW AHEAD OF THIS SYSTEM WILL BRING WARM AIR
INTO THE REGION LATE MONDAY INTO TUESDAY. BY TUESDAY AND WEDNESDAY
MANY LOW- LEVEL TEMPERATURE AND MOISTURE FIELDS WILL BE WELL ABOVE
THEIR SEASONAL VALUES. THIS IMPLIES VERY WARM WEATHER TUESDAY AND
WEDNESDAY...WHEN THE SHALLOW COLD AIR SCOURS OUT EAST OF THE
MOUNTAINS.

A COLD FRONT WITH STRONG WINDS WILL PRODUCE COLDER
CONDITIONS...LIKELY LATE CHRISTMAS EVE INTO CHRISTMAS DAY. THERE
WILL BE STRONG WESTERLY WINDS AND STRONG WIND GUSTS. SNOW SHOWERS
ARE LIKELY BEHIND THE SYSTEM IN WESTERN AREAS.

THE CHANGEABLE DETAILS...MONDAY THE ENSEMBLE FORECAST SHOWS A
WAVE PASSING TO OUR SOUTH WHICH COULD PRODUCE LIGHT SNOW OR A
MIX...MAINLY IN SOUTHEASTERN AREAS. THE IMPLIED LOW-LEVEL BOUNDARY
IS THE RETREATING COLD AIR TO OUR NORTHEAST AS THE STRONG CYCLONE
TO OUR WEST BEGINS TO TAKE SHAPE. IMPLIED LOW-LEVEL AGEOSTROPHIC
NORTHERLY FLOW HOLDING LOW-LEVEL COLD AIR IN MONDAY INTO TUESDAY.

TUESDAY THE COLD AIR SHOULD CONTINUE TO ERODE. HAD TO KEEP SOME
FREEZE RAIN/DRIZZLE IN NORTHEASTERN AREAS OVERNIGHT MONDAY INTO
TUESDAY BASED ON IMPLIED AGEOSTROPHIC FLOW AND ENSEMBLE
PRECIPITATION TYPES. BUT DURING THE DAY TUESDAY THE WARM AIR
SHOULD WIN OUT. THOUGH ALL SYSTEMS SHOW SOME HINTS OF COLD AIR
DAMMING....DAYTIME HIGHS EAST/NORTHEAST AREAS WILL BE WELL BELOW
WHAT ONE MIGHT EXPECT WITH 6-10C 850 MB TEMPS.

ANY PRECIPITATION TUESDAY AND WEDNESDAY SHOULD BE RAIN MUCH AFTER
NOON TUESDAY IN THE NORTHEAST. PRECIPITATION ON TUESDAY SHOULD BE
LIGHT...ENSEMBLES SHOW PROBABILITIES IN THE 20-30 RANGE AND LIGHT
AMOUNTS. THE PATTERN...SHARP NORTH-SOUTH FRONT TO OUR
WEST...IMPLIES SOME ISOLATED SHOWERS BUT THE MAIN RAIN EVENT
SHOULD WITHIN 3-6 HOURS OF THE FRONT.

TUESDAY THE STRONG CYCLONE...WITH SOME OF THE LOWEST SURFACE
PRESSURES IN THE EASTERN US ON 24 DECEMBER IN THE PAST 30 YEARS
WILL MOVE INTO THE GREAT LAKES. PRESSURE ANOMALIES ARE -3 TO -4
SIGMA BELOW NORMAL WITH A RETURN PERIOD ON THE ORDER OF 30 YEARS
IN SOME FORECAST SYSTEMS.

THE FRONT ASSOCIATED WITH THE CYCLONE PUSHES INTO OUR REGION
WEDNESDAY...AT THIS TIME THE 850 MB SOUTHERLY WINDS ARE FORECAST
TO BE ABOUT +3 SIGMA ABOVE NORMAL. THE STRONG SOUTHERLY FLOW...THE
HIGH PRECIPITABLE WATER...THE STRONG FRONT ALL IMPLY A FRONTAL
RAIN EVENT AND PERHAPS SOME RARE LATE DECEMBER (ELEVATED)
CONVECTION. IF THIS WERE AUTUMN OR SPRING WE MIGHT BE THINKING
QLCS. BUT SURFACE CAPE IS VIRTUALLY NON-EXISTENT BUT SHOWERY RAIN
AND PERHAPS ISOLATED THUNDER POSSIBLE.

DO NOT LIKE HAVING POPS ABOVE 60 TO 66 PERCENT AT DAY 5 IN 12 HOUR
PERIODS. TIMING WILL CLEARLY CHANGE BUT HAVE HIGH POPS FOR
CONSISTENCY WITH OTHER OFFICES.

CHRISTMAS EVE AND EARLY CHRISTMAS IS THE AREA OF HIGH UNCERTAINTY
AS TO WHEN THE COLD AIR COMES IN. THIS WILL DICTATE WHEN THE RAIN
COMES AND WHEN THE GUSTY WINDS SET IN. GRADIENTS ARE WHERE
FORECASTS ARE THEIR POOREST. BUT BY CHRISTMAS MORNING MOST IF NOT
ALL OF THE REGION SHOULD BE BELOW 0C AT 850 AND THE STRONG
WESTERLY WINDS SHOULD BE MIXING DOWN BEHIND THE FRONTAL BOUNDARY.
WINDY OVERNIGHT CHRISTMAS EVE INTO CHRISTMAS DAY. ANY RESIDUAL
PRECIPITATION SHOULD BE SNOW/SNOW SHOWERS AND FLURRIES.

TEMPERATURES SHOULD REBOUND FRIDAY AHEAD OF ANOTHER NORTHERN STREAM
WAVE MOVING INTO THE MID-WEST. THIS SHOULD RAISE OUR HEIGHTS AND
TEMPERATURES FRIDAY INTO EARLY SATURDAY. IT APPEARS A SERIES OF
WAVES MAY EVENTUALLY CARVE OUT A TROUGH OVER THE EAST-CENTRAL US. IF
SO...WE COULD END DECEMBER A BIT ON THE CHILLY SIDE.

&&

.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
A WEAK AND SHALLOW STRATOCU DECK REMAINS TRAPPED BENEATH
SUBSIDENCE. THE CIG RESTRICTIONS WILL SPREAD AND INCREASE DUE TO
THE STRENGTHENING OF THE INVERSION OVERNIGHT. EXPECT THE
EXPANDING STRATOCU DECK LIKELY TO RETURN AGAIN TONIGHT...THOUGH
LOW CLOUDS SHOULD NOT BE QUITE AS EXPANSIVE AS PREVIOUS NIGHTS. A
SHORTWAVE WILL TRACK ACROSS THE REGION BRINGING A THICKENING MID-
LVL DECK AS WELL. SURFACE WINDS WILL CONTINUE TO BE LIGHT...WITH
SW FLOW ALOFT BEGINNING TO INCREASE AS A LARGE LOW PRESSURE SYSTEM
BEGINS TO DEEPEN OVER THE CENTRAL U.S. EXPECT MVFR CIGS AT THE
CENTRAL SITES AOO AND UNV...WITH IFR POSSIBLE AT BFD AND
JST...WITH MAINLY VFR THROUGH THE EASTERN TAF SITES.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

THU...WINDY AND COLDER WITH SCT MVFR CIGS AND -SHSN.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DEVOIR
LONG TERM...GRUMM
AVIATION...DEVOIR/CERU




000
FXUS61 KCTP 210234
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
934 PM EST SAT DEC 20 2014

.SYNOPSIS...
AN AMPLIFYING UPPER RIDGE WILL MOVE INTO THE REGION ON
SUNDAY. TEMPERATURES WILL THEN BECOME JUST SLIGHTLY MILDER BUT
UNSETTLED CONDITIONS WILL BEGIN ON MONDAY NIGHT AND PREVAIL
THROUGH MID WEEK. A VIGOROUS STORM SYSTEM WILL SWEEP ACROSS THE
COMMONWEALTH ON CHRISTMAS EVE BRINGING WIDESPREAD SHOWERS AND A
CHANCE FOR THUNDERSTORMS. WINDY AND COLDER CONDITIONS WILL FOLLOW
WITH SCATTERED SNOW SHOWERS ACROSS THE WEST AND NORTH FOR
CHRISTMAS DAY. MILDER CONDITIONS WILL RETURN LATE THIS WEEK.

&&

.NEAR TERM /UNTIL 8 AM SUNDAY MORNING/...
CLOUDS COVERING ALL OF THE AREA AS A VIGOROUS SHORT WAVE ROLLS
OVERHEAD EARLY TONIGHT. ENOUGH LIFT PRESENT TO MAKE SOME ICE
CRYSTALS FALL OUT OF THE MID DECK AND SEED THE LOWER CLOUDS.
THUS...SOME FLURRIES ARE EXPECTED MAINLY EARLY TONIGHT OVER THE
LAURELS AND ALL NIGHT ALONG THE NRN TIER. WILL LEAVE ACCUMS OUT
OF THE FCST...BUT THE LIGHTEST OF DUSTINGS IS POSSIBLE. MINS
PROBABLY A HOMOGENEOUS 20-25F ACROSS THE BOARD.

&&

.SHORT TERM /8 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
DEEP LAYER DRYING BEHIND A DEPARTING 5H WAVE AND UPPER LEVEL
RIDGING HAS THE POTENTIAL TO BRING SUNSHINE TO MOST IF NOT ALL OF
CENTRAL PA ON MONDAY. THE STUBBORN STRATUS THAT HAS PLAGUED US FOR
MORE THAN A WEEK WILL HAVE A CHANCE TO MIX OUT...BUT TRANSITORY
SFC HIGH PRESSURE MAY STILL MAKE THIS A SLOW PROCESS OVER THE
NORTH.

PRIOR TO THAT...SOME AREAS COULD PERHAPS SEE A FLURRY IN THE PRE
DAWN HOURS SUNDAY BEFORE THE WAVE QUICKLY EXITS EASTWARD. WENT
CLOSE TO CONSALL GUIDANCE AGAIN WITH MAXES REACHING THE MID TO
UPPER 30S NORTH TO THE LOWER 40S SOUTH.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
THE MOST SIGNIFICANT FORECAST ISSUE IN THE LONG TERM IS THE
EVOLUTION OF THE MASSIVE CYCLONE TO OUR WEST 23-25 DECEMBER.
STRONG SOUTHERLY FLOW AHEAD OF THIS SYSTEM WILL BRING WARM AIR
INTO THE REGION LATE MONDAY INTO TUESDAY. BY TUESDAY AND WEDNESDAY
MANY LOW- LEVEL TEMPERATURE AND MOISTURE FIELDS WILL BE WELL ABOVE
THEIR SEASONAL VALUES. THIS IMPLIES VERY WARM WEATHER TUESDAY AND
WEDNESDAY...WHEN THE SHALLOW COLD AIR SCOURS OUT EAST OF THE
MOUNTAINS.

A COLD FRONT WITH STRONG WINDS WILL PRODUCE COLDER
CONDITIONS...LIKELY LATE CHRISTMAS EVE INTO CHRISTMAS DAY. THERE
WILL BE STRONG WESTERLY WINDS AND STRONG WIND GUSTS. SNOW SHOWERS
ARE LIKELY BEHIND THE SYSTEM IN WESTERN AREAS.

THE CHANGEABLE DETAILS...MONDAY THE ENSEMBLE FORECAST SHOWS A
WAVE PASSING TO OUR SOUTH WHICH COULD PRODUCE LIGHT SNOW OR A
MIX...MAINLY IN SOUTHEASTERN AREAS. THE IMPLIED LOW-LEVEL BOUNDARY
IS THE RETREATING COLD AIR TO OUR NORTHEAST AS THE STRONG CYCLONE
TO OUR WEST BEGINS TO TAKE SHAPE. IMPLIED LOW-LEVEL AGEOSTROPHIC
NORTHERLY FLOW HOLDING LOW-LEVEL COLD AIR IN MONDAY INTO TUESDAY.

TUESDAY THE COLD AIR SHOULD CONTINUE TO ERODE. HAD TO KEEP SOME
FREEZE RAIN/DRIZZLE IN NORTHEASTERN AREAS OVERNIGHT MONDAY INTO
TUESDAY BASED ON IMPLIED AGEOSTROPHIC FLOW AND ENSEMBLE
PRECIPITATION TYPES. BUT DURING THE DAY TUESDAY THE WARM AIR
SHOULD WIN OUT. THOUGH ALL SYSTEMS SHOW SOME HINTS OF COLD AIR
DAMMING....DAYTIME HIGHS EAST/NORTHEAST AREAS WILL BE WELL BELOW
WHAT ONE MIGHT EXPECT WITH 6-10C 850 MB TEMPS.

ANY PRECIPITATION TUESDAY AND WEDNESDAY SHOULD BE RAIN MUCH AFTER
NOON TUESDAY IN THE NORTHEAST. PRECIPITATION ON TUESDAY SHOULD BE
LIGHT...ENSEMBLES SHOW PROBABILITIES IN THE 20-30 RANGE AND LIGHT
AMOUNTS. THE PATTERN...SHARP NORTH-SOUTH FRONT TO OUR
WEST...IMPLIES SOME ISOLATED SHOWERS BUT THE MAIN RAIN EVENT
SHOULD WITHIN 3-6 HOURS OF THE FRONT.

TUESDAY THE STRONG CYCLONE...WITH SOME OF THE LOWEST SURFACE
PRESSURES IN THE EASTERN US ON 24 DECEMBER IN THE PAST 30 YEARS
WILL MOVE INTO THE GREAT LAKES. PRESSURE ANOMALIES ARE -3 TO -4
SIGMA BELOW NORMAL WITH A RETURN PERIOD ON THE ORDER OF 30 YEARS
IN SOME FORECAST SYSTEMS.

THE FRONT ASSOCIATED WITH THE CYCLONE PUSHES INTO OUR REGION
WEDNESDAY...AT THIS TIME THE 850 MB SOUTHERLY WINDS ARE FORECAST
TO BE ABOUT +3 SIGMA ABOVE NORMAL. THE STRONG SOUTHERLY FLOW...THE
HIGH PRECIPITABLE WATER...THE STRONG FRONT ALL IMPLY A FRONTAL
RAIN EVENT AND PERHAPS SOME RARE LATE DECEMBER (ELEVATED)
CONVECTION. IF THIS WERE AUTUMN OR SPRING WE MIGHT BE THINKING
QLCS. BUT SURFACE CAPE IS VIRTUALLY NON-EXISTENT BUT SHOWERY RAIN
AND PERHAPS ISOLATED THUNDER POSSIBLE.

DO NOT LIKE HAVING POPS ABOVE 60 TO 66 PERCENT AT DAY 5 IN 12 HOUR
PERIODS. TIMING WILL CLEARLY CHANGE BUT HAVE HIGH POPS FOR
CONSISTENCY WITH OTHER OFFICES.

CHRISTMAS EVE AND EARLY CHRISTMAS IS THE AREA OF HIGH UNCERTAINTY
AS TO WHEN THE COLD AIR COMES IN. THIS WILL DICTATE WHEN THE RAIN
COMES AND WHEN THE GUSTY WINDS SET IN. GRADIENTS ARE WHERE
FORECASTS ARE THEIR POOREST. BUT BY CHRISTMAS MORNING MOST IF NOT
ALL OF THE REGION SHOULD BE BELOW 0C AT 850 AND THE STRONG
WESTERLY WINDS SHOULD BE MIXING DOWN BEHIND THE FRONTAL BOUNDARY.
WINDY OVERNIGHT CHRISTMAS EVE INTO CHRISTMAS DAY. ANY RESIDUAL
PRECIPITATION SHOULD BE SNOW/SNOW SHOWERS AND FLURRIES.

TEMPERATURES SHOULD REBOUND FRIDAY AHEAD OF ANOTHER NORTHERN STREAM
WAVE MOVING INTO THE MID-WEST. THIS SHOULD RAISE OUR HEIGHTS AND
TEMPERATURES FRIDAY INTO EARLY SATURDAY. IT APPEARS A SERIES OF
WAVES MAY EVENTUALLY CARVE OUT A TROUGH OVER THE EAST-CENTRAL US. IF
SO...WE COULD END DECEMBER A BIT ON THE CHILLY SIDE.

&&

.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
A WEAK AND SHALLOW STRATOCU DECK REMAINS TRAPPED BENEATH
SUBSIDENCE. THE CIG RESTRICTIONS WILL SPREAD AND INCREASE DUE TO
THE STRENGTHENING OF THE INVERSION OVERNIGHT. EXPECT THE
EXPANDING STRATOCU DECK LIKELY TO RETURN AGAIN TONIGHT...THOUGH
LOW CLOUDS SHOULD NOT BE QUITE AS EXPANSIVE AS PREVIOUS NIGHTS. A
SHORTWAVE WILL TRACK ACROSS THE REGION BRINGING A THICKENING MID-
LVL DECK AS WELL. SURFACE WINDS WILL CONTINUE TO BE LIGHT...WITH
SW FLOW ALOFT BEGINNING TO INCREASE AS A LARGE LOW PRESSURE SYSTEM
BEGINS TO DEEPEN OVER THE CENTRAL U.S. EXPECT MVFR CIGS AT THE
CENTRAL SITES AOO AND UNV...WITH IFR POSSIBLE AT BFD AND
JST...WITH MAINLY VFR THROUGH THE EASTERN TAF SITES.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

THU...WINDY AND COLDER WITH SCT MVFR CIGS AND -SHSN.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DEVOIR
LONG TERM...GRUMM
AVIATION...DEVOIR/CERU


  [top]

000
FXUS61 KPBZ 210217
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
917 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE WILL BE IN CONTROL INTO MONDAY. EXPECT INCREASING
PRECIPITATION CHANCES TUESDAY. STORM SYSTEM BRINGS RAIN AND WIND
CHRISTMAS EVE...AND SNOW SHOWERS CHRISTMAS DAY.

&&

.NEAR TERM /THROUGH SUNDAY/...
PRIMARY CHANGE WITH 915PM UPDATE WAS TO ADD SCATTERED FLURRIES
FROM PITTSBURGH AND TO THE NORTH AND WEST. SOME LIGHT RADAR ECHOES
HAVE MOVED FROM INDIANA INTO OHIO DURING THE AFTERNOON AND EARLY
EVENING HOURS...WITH A COUPLE OF AUTOMATED STATIONS REPORTING
LIGHT SNOW. IN THE LAST HOUR THREE SITES AROUND COLUMBUS OHIO HAVE
REPORTED SNOW...AND EXPECT THAT THIS FLURRY ACTIVITY COULD
CONTINUE AS IT IS ASSOCIATED WITH AN UPPER LEVEL SHORTWAVE MOVING
THROUGH THE REGION. FLURRIES SHOULD COME TO AN END AFTER MIDNIGHT.
A SLIGHT CHANCE OF LIGHT SNOW STILL CANNOT BE RULED OUT SOUTH AND
EAST OF PITTSBURGH WITH ANOTHER FEATURE...BUT NO ACCUMULATIONS ARE
EXPECTED ANYWHERE OVERNIGHT.

INVERSION IS MAINTAINED SUNDAY MORNING WHICH WILL MAINTAIN STRATUS
DECK...BUT BY AFTERNOON EXPECT STRATUS TO MIX OUT INTO A CU FIELD
AND THEN SCATTER OUT BY EVENING. A BIT MORE SUN SHOULD ALLOW FOR
AFTERNOON HIGH TEMPS AROUND 5 DEGREES WARMER THAN TODAY. CL

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
BENIGN WEATHER INITIALLY WITH HIGH PRESSURE TO OUR EAST AND IN
CONTROL.  SOUTHEAST WINDS IN RESPONSE TO SURFACE ANTICYCLONE
POSITION WILL FACILITATE DEVELOPMENT OF STRATUS OVER EASTERN
PORTIONS OF TUCKER AND GARRETT COUNTIES MONDAY INTO MONDAY NIGHT.
PCPN ONSET HAS SLOWED DOWN FROM PREVIOUS CYCLES...BUT THERE REMAINS
A VERY LOW PROBABILITY OF FREEZING RAIN AND/OR SLEET OVER
AFOREMENTIONED AREAS MONDAY.  FOR NOW...TRENDED FORECAST WITH PCPN
COMMENCING DURING THE AFTERNOON WHICH REFLECT LATEST NUMERICAL
MODELS.  WITH THIS SCENARIO...LOW LEVEL SUB-FREEZING AIR SHOULD
SCOUR OUT YIELDING AN ALL RAIN PTYPE.

RAIN SHADOW EFFECT TAKES PLACES TUESDAY WITH SOUTHEAST WINDS
WIDESPREAD OVER THE REGION. AN ISOLATED SHOWER REACHING EASTERN OHIO
AND FAR NWRN PA IS NOT OUT OF THE QUESTION...SO KEPT A SLIGHT
CHANCE.  WOULD NOT BE SURPRISED TO SEE BREAKS IN THE CLOUDS WHICH
COULD ALLOW FOR A FEW LOCATIONS TO EXCEED 60 DEGREES.  RECORD HIGHS
FOR PITTSBURGH...MORGANTOWN...AND ZANESVILLE ALL RESIDE WELL INTO
THE UPPER 60S...SO AT THIS JUNCTURE RECORD WARMTH IS NOT FORESEEN.
PRECIP ASSOCIATED WITH THE SURFACE LOW PRESSURE SYSTEM EJECTING FROM
THE GULF COAST REGION REACHES SERN AREAS OF THE FORECAST AREA THAT
EVENING.

A BLEND OF THE ONGOING FORECAST AND BIAS CORRECTED ECMWF WERE USED
FOR TEMPERATURES.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
HIGHLIGHTS:
- A WET CHRISTMAS EVE
- TEMPERATURES RETURN BACK TO NORMAL VALUES CHRISTMAS DAY
- SLIGHTLY ABOVE NORMAL TEMPERATURES RETURN BY FRIDAY

STRONG LOW PRESSURE SYSTEM THAT HAS BEEN MUCH ADVERTISED GIVEN THE
TIME PERIOD WHICH IT AFFECTS OUR AREA IS STILL ON TRACK.  LONG RANGE
ENSEMBLE PREDICTION SYSTEMS AND OPERATIONAL MODELS ARE CONVERGING ON
A TRACK THROUGH IND / ILL THEN NORTH INTO CANADA.  THIS WILL MAKE
FOR ALL LIQUID PRECIPITATION ON THE FRONT END.  TEMPERATURES WILL
SOAR TO NEARLY 20 DEGREES ABOVE NORMAL WEDNESDAY WITH 50S COMMON.
COUPLED WITH INFLUX OF MOISTURE FROM THE GULF OF MEXICO...SOUNDINGS
ILLUSTRATE ELEVATED INSTABILITY WHICH PUSHES TEMP DIFFERENTIAL
BETWEEN H8 AND H5 TO NEARLY 0C.  THIS COULD LEAD TO ISOLATED
THUNDERSTORMS AHEAD OF THE BAROCLINIC ZONE.  FOR THE TIME
BEING...OPTED TO LEAVE THUNDER OUT OF THE FORECAST AND WAIT FOR
BETTER CONTINUITY GIVEN THIS STILL IS FIVE DAYS OUT.  DESPITE PWATS
NEARLY TWO STANDARD DEVIATIONS ABOVE NORMAL...COMBINATION OF
KATABATIC WINDS AND DRY CONVEYOR BELT WILL LIMIT QPF POTENTIAL TO
NEGATE ANY FLOOD THREAT.  LONG RANGE HYDROLOGIC MODELS SHOW VERY
LITTLE RISE IN AREA RIVERS...WHICH CORRELATES WELL TO THE PROJECTED
QPF OF 0.50 TO 1.00".

WITH THE TRACK OF THE CYCLONE DUE N...COLD AIR INJECTED INTO THE
AREA WILL BE OF MIDWEST ORIGIN...SO TEMPS WILL RETREAT BACK TO
SEASONAL BENCHMARKS CHRISTMAS DAY.  FOR THOSE WHO ARE LOOKING FOR
SNOW ON CHRISTMAS...A CHANCE OF SNOW SHOWERS EXIST...BUT GIVEN
TRAJECTORY FROM THE SOUTHWEST ANY ACCUMULATION ASSOCIATED WITH THE
UPPER LEVEL SYSTEM WILL BE LIGHT AT BEST.  HISTORICALLY...THERE IS
ONLY A 17 PERCENT CHANCE OF AT LEAST ONE INCH OF SNOW ON THE GROUND
AT PITTSBURGH CHRISTMAS MORNING.

H8 WINDS PUSH 50KTS WEDNESDAY NIGHT INTO THURSDAY AND HIGHEST
ANOMALIES RESIDE ALONG THE LAKE SHORE...SO EXPECT HIGHEST GUSTS
WOULD DO SO AS WELL.  NONETHELESS...PERIOD FROM WEDNESDAY NIGHT INTO
THURSDAY STRONG ISALLOBARIC FLOW COULD YIELD GUSTS IN EXCESS OF 40
MPH ESPECIALLY IN THE MOUNTAINS OF WRN MD AND NRN WV.

BALANCE OF THE EXTENDED IS CHARACTERIZED BY UNCERTAINTY AS ONE WOULD
EXPECT IN THE DAY 6 -7 TIME FRAME.  ECMWF HAS A STRONGER SYSTEM
CROSSING FRIDAY NIGHT VERSUS GFS WHICH IS MUCH WEAKER.  EITHER CASE
PTYPE SHOULD BE RAIN WITH SNOW SHOWERS ON THE BACKSIDE.  NO PLUNGES
OF ARCTIC AIR ARE FORECAST IN THE NEXT 10 DAYS.  MAX/MIN
TEMPERATURES WERE A BLEND OF THE FORECAST AND ECMWF BIAS CORRECTED
DATA SET.

&&

.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
WHILE FKL...DUJ...AND ZZV ARE EXPECTED TO REMAIN UNDER MVFR CIGS
OVERNIGHT...REMAINING TERMINALS MAY CONTINUE TO HAVE LOWER CLOUDS
SCATTER OUT LEAVING A MID DECK TEMPORARILY. BY MIDNIGHT ALL
TERMINALS ARE EXPECTED TO RETURN TO UNIFORM MVFR CIGS. CANNOT RULE
OUT SOME CIGS BELOW 2KFT BUT DID NOT HAVE CONFIDENCE TO INCLUDE
THEM. UNCERTAINTY REMAINS AS TO WHEN SKIES SHOULD SCATTER OUT ON
SUNDAY. THE SCATTERING TREND SHOULD MOVE FROM SOUTHWEST TO
NORTHEAST...BUT CURRENT FORECAST DOES NOT ELIMINATE CIG FROM
PITTSBURGH AND LOCATIONS NORTHEAST UNTIL 00Z MONDAY.


OUTLOOK.../SUNDAY NIGHT THROUGH THURSDAY/...
NEXT STORM SYSTEM WILL BEGIN TO IMPACT THE REGION ON TUESDAY AND
RESULT IN WIDESPREAD RAIN...CIG/VIS RESTRICTIONS...AND PERIODS OF
LLWS INTO THURSDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$






000
FXUS61 KPBZ 210217
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
917 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE WILL BE IN CONTROL INTO MONDAY. EXPECT INCREASING
PRECIPITATION CHANCES TUESDAY. STORM SYSTEM BRINGS RAIN AND WIND
CHRISTMAS EVE...AND SNOW SHOWERS CHRISTMAS DAY.

&&

.NEAR TERM /THROUGH SUNDAY/...
PRIMARY CHANGE WITH 915PM UPDATE WAS TO ADD SCATTERED FLURRIES
FROM PITTSBURGH AND TO THE NORTH AND WEST. SOME LIGHT RADAR ECHOES
HAVE MOVED FROM INDIANA INTO OHIO DURING THE AFTERNOON AND EARLY
EVENING HOURS...WITH A COUPLE OF AUTOMATED STATIONS REPORTING
LIGHT SNOW. IN THE LAST HOUR THREE SITES AROUND COLUMBUS OHIO HAVE
REPORTED SNOW...AND EXPECT THAT THIS FLURRY ACTIVITY COULD
CONTINUE AS IT IS ASSOCIATED WITH AN UPPER LEVEL SHORTWAVE MOVING
THROUGH THE REGION. FLURRIES SHOULD COME TO AN END AFTER MIDNIGHT.
A SLIGHT CHANCE OF LIGHT SNOW STILL CANNOT BE RULED OUT SOUTH AND
EAST OF PITTSBURGH WITH ANOTHER FEATURE...BUT NO ACCUMULATIONS ARE
EXPECTED ANYWHERE OVERNIGHT.

INVERSION IS MAINTAINED SUNDAY MORNING WHICH WILL MAINTAIN STRATUS
DECK...BUT BY AFTERNOON EXPECT STRATUS TO MIX OUT INTO A CU FIELD
AND THEN SCATTER OUT BY EVENING. A BIT MORE SUN SHOULD ALLOW FOR
AFTERNOON HIGH TEMPS AROUND 5 DEGREES WARMER THAN TODAY. CL

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
BENIGN WEATHER INITIALLY WITH HIGH PRESSURE TO OUR EAST AND IN
CONTROL.  SOUTHEAST WINDS IN RESPONSE TO SURFACE ANTICYCLONE
POSITION WILL FACILITATE DEVELOPMENT OF STRATUS OVER EASTERN
PORTIONS OF TUCKER AND GARRETT COUNTIES MONDAY INTO MONDAY NIGHT.
PCPN ONSET HAS SLOWED DOWN FROM PREVIOUS CYCLES...BUT THERE REMAINS
A VERY LOW PROBABILITY OF FREEZING RAIN AND/OR SLEET OVER
AFOREMENTIONED AREAS MONDAY.  FOR NOW...TRENDED FORECAST WITH PCPN
COMMENCING DURING THE AFTERNOON WHICH REFLECT LATEST NUMERICAL
MODELS.  WITH THIS SCENARIO...LOW LEVEL SUB-FREEZING AIR SHOULD
SCOUR OUT YIELDING AN ALL RAIN PTYPE.

RAIN SHADOW EFFECT TAKES PLACES TUESDAY WITH SOUTHEAST WINDS
WIDESPREAD OVER THE REGION. AN ISOLATED SHOWER REACHING EASTERN OHIO
AND FAR NWRN PA IS NOT OUT OF THE QUESTION...SO KEPT A SLIGHT
CHANCE.  WOULD NOT BE SURPRISED TO SEE BREAKS IN THE CLOUDS WHICH
COULD ALLOW FOR A FEW LOCATIONS TO EXCEED 60 DEGREES.  RECORD HIGHS
FOR PITTSBURGH...MORGANTOWN...AND ZANESVILLE ALL RESIDE WELL INTO
THE UPPER 60S...SO AT THIS JUNCTURE RECORD WARMTH IS NOT FORESEEN.
PRECIP ASSOCIATED WITH THE SURFACE LOW PRESSURE SYSTEM EJECTING FROM
THE GULF COAST REGION REACHES SERN AREAS OF THE FORECAST AREA THAT
EVENING.

A BLEND OF THE ONGOING FORECAST AND BIAS CORRECTED ECMWF WERE USED
FOR TEMPERATURES.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
HIGHLIGHTS:
- A WET CHRISTMAS EVE
- TEMPERATURES RETURN BACK TO NORMAL VALUES CHRISTMAS DAY
- SLIGHTLY ABOVE NORMAL TEMPERATURES RETURN BY FRIDAY

STRONG LOW PRESSURE SYSTEM THAT HAS BEEN MUCH ADVERTISED GIVEN THE
TIME PERIOD WHICH IT AFFECTS OUR AREA IS STILL ON TRACK.  LONG RANGE
ENSEMBLE PREDICTION SYSTEMS AND OPERATIONAL MODELS ARE CONVERGING ON
A TRACK THROUGH IND / ILL THEN NORTH INTO CANADA.  THIS WILL MAKE
FOR ALL LIQUID PRECIPITATION ON THE FRONT END.  TEMPERATURES WILL
SOAR TO NEARLY 20 DEGREES ABOVE NORMAL WEDNESDAY WITH 50S COMMON.
COUPLED WITH INFLUX OF MOISTURE FROM THE GULF OF MEXICO...SOUNDINGS
ILLUSTRATE ELEVATED INSTABILITY WHICH PUSHES TEMP DIFFERENTIAL
BETWEEN H8 AND H5 TO NEARLY 0C.  THIS COULD LEAD TO ISOLATED
THUNDERSTORMS AHEAD OF THE BAROCLINIC ZONE.  FOR THE TIME
BEING...OPTED TO LEAVE THUNDER OUT OF THE FORECAST AND WAIT FOR
BETTER CONTINUITY GIVEN THIS STILL IS FIVE DAYS OUT.  DESPITE PWATS
NEARLY TWO STANDARD DEVIATIONS ABOVE NORMAL...COMBINATION OF
KATABATIC WINDS AND DRY CONVEYOR BELT WILL LIMIT QPF POTENTIAL TO
NEGATE ANY FLOOD THREAT.  LONG RANGE HYDROLOGIC MODELS SHOW VERY
LITTLE RISE IN AREA RIVERS...WHICH CORRELATES WELL TO THE PROJECTED
QPF OF 0.50 TO 1.00".

WITH THE TRACK OF THE CYCLONE DUE N...COLD AIR INJECTED INTO THE
AREA WILL BE OF MIDWEST ORIGIN...SO TEMPS WILL RETREAT BACK TO
SEASONAL BENCHMARKS CHRISTMAS DAY.  FOR THOSE WHO ARE LOOKING FOR
SNOW ON CHRISTMAS...A CHANCE OF SNOW SHOWERS EXIST...BUT GIVEN
TRAJECTORY FROM THE SOUTHWEST ANY ACCUMULATION ASSOCIATED WITH THE
UPPER LEVEL SYSTEM WILL BE LIGHT AT BEST.  HISTORICALLY...THERE IS
ONLY A 17 PERCENT CHANCE OF AT LEAST ONE INCH OF SNOW ON THE GROUND
AT PITTSBURGH CHRISTMAS MORNING.

H8 WINDS PUSH 50KTS WEDNESDAY NIGHT INTO THURSDAY AND HIGHEST
ANOMALIES RESIDE ALONG THE LAKE SHORE...SO EXPECT HIGHEST GUSTS
WOULD DO SO AS WELL.  NONETHELESS...PERIOD FROM WEDNESDAY NIGHT INTO
THURSDAY STRONG ISALLOBARIC FLOW COULD YIELD GUSTS IN EXCESS OF 40
MPH ESPECIALLY IN THE MOUNTAINS OF WRN MD AND NRN WV.

BALANCE OF THE EXTENDED IS CHARACTERIZED BY UNCERTAINTY AS ONE WOULD
EXPECT IN THE DAY 6 -7 TIME FRAME.  ECMWF HAS A STRONGER SYSTEM
CROSSING FRIDAY NIGHT VERSUS GFS WHICH IS MUCH WEAKER.  EITHER CASE
PTYPE SHOULD BE RAIN WITH SNOW SHOWERS ON THE BACKSIDE.  NO PLUNGES
OF ARCTIC AIR ARE FORECAST IN THE NEXT 10 DAYS.  MAX/MIN
TEMPERATURES WERE A BLEND OF THE FORECAST AND ECMWF BIAS CORRECTED
DATA SET.

&&

.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
WHILE FKL...DUJ...AND ZZV ARE EXPECTED TO REMAIN UNDER MVFR CIGS
OVERNIGHT...REMAINING TERMINALS MAY CONTINUE TO HAVE LOWER CLOUDS
SCATTER OUT LEAVING A MID DECK TEMPORARILY. BY MIDNIGHT ALL
TERMINALS ARE EXPECTED TO RETURN TO UNIFORM MVFR CIGS. CANNOT RULE
OUT SOME CIGS BELOW 2KFT BUT DID NOT HAVE CONFIDENCE TO INCLUDE
THEM. UNCERTAINTY REMAINS AS TO WHEN SKIES SHOULD SCATTER OUT ON
SUNDAY. THE SCATTERING TREND SHOULD MOVE FROM SOUTHWEST TO
NORTHEAST...BUT CURRENT FORECAST DOES NOT ELIMINATE CIG FROM
PITTSBURGH AND LOCATIONS NORTHEAST UNTIL 00Z MONDAY.


OUTLOOK.../SUNDAY NIGHT THROUGH THURSDAY/...
NEXT STORM SYSTEM WILL BEGIN TO IMPACT THE REGION ON TUESDAY AND
RESULT IN WIDESPREAD RAIN...CIG/VIS RESTRICTIONS...AND PERIODS OF
LLWS INTO THURSDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$






000
FXUS61 KPBZ 210217
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
917 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE WILL BE IN CONTROL INTO MONDAY. EXPECT INCREASING
PRECIPITATION CHANCES TUESDAY. STORM SYSTEM BRINGS RAIN AND WIND
CHRISTMAS EVE...AND SNOW SHOWERS CHRISTMAS DAY.

&&

.NEAR TERM /THROUGH SUNDAY/...
PRIMARY CHANGE WITH 915PM UPDATE WAS TO ADD SCATTERED FLURRIES
FROM PITTSBURGH AND TO THE NORTH AND WEST. SOME LIGHT RADAR ECHOES
HAVE MOVED FROM INDIANA INTO OHIO DURING THE AFTERNOON AND EARLY
EVENING HOURS...WITH A COUPLE OF AUTOMATED STATIONS REPORTING
LIGHT SNOW. IN THE LAST HOUR THREE SITES AROUND COLUMBUS OHIO HAVE
REPORTED SNOW...AND EXPECT THAT THIS FLURRY ACTIVITY COULD
CONTINUE AS IT IS ASSOCIATED WITH AN UPPER LEVEL SHORTWAVE MOVING
THROUGH THE REGION. FLURRIES SHOULD COME TO AN END AFTER MIDNIGHT.
A SLIGHT CHANCE OF LIGHT SNOW STILL CANNOT BE RULED OUT SOUTH AND
EAST OF PITTSBURGH WITH ANOTHER FEATURE...BUT NO ACCUMULATIONS ARE
EXPECTED ANYWHERE OVERNIGHT.

INVERSION IS MAINTAINED SUNDAY MORNING WHICH WILL MAINTAIN STRATUS
DECK...BUT BY AFTERNOON EXPECT STRATUS TO MIX OUT INTO A CU FIELD
AND THEN SCATTER OUT BY EVENING. A BIT MORE SUN SHOULD ALLOW FOR
AFTERNOON HIGH TEMPS AROUND 5 DEGREES WARMER THAN TODAY. CL

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
BENIGN WEATHER INITIALLY WITH HIGH PRESSURE TO OUR EAST AND IN
CONTROL.  SOUTHEAST WINDS IN RESPONSE TO SURFACE ANTICYCLONE
POSITION WILL FACILITATE DEVELOPMENT OF STRATUS OVER EASTERN
PORTIONS OF TUCKER AND GARRETT COUNTIES MONDAY INTO MONDAY NIGHT.
PCPN ONSET HAS SLOWED DOWN FROM PREVIOUS CYCLES...BUT THERE REMAINS
A VERY LOW PROBABILITY OF FREEZING RAIN AND/OR SLEET OVER
AFOREMENTIONED AREAS MONDAY.  FOR NOW...TRENDED FORECAST WITH PCPN
COMMENCING DURING THE AFTERNOON WHICH REFLECT LATEST NUMERICAL
MODELS.  WITH THIS SCENARIO...LOW LEVEL SUB-FREEZING AIR SHOULD
SCOUR OUT YIELDING AN ALL RAIN PTYPE.

RAIN SHADOW EFFECT TAKES PLACES TUESDAY WITH SOUTHEAST WINDS
WIDESPREAD OVER THE REGION. AN ISOLATED SHOWER REACHING EASTERN OHIO
AND FAR NWRN PA IS NOT OUT OF THE QUESTION...SO KEPT A SLIGHT
CHANCE.  WOULD NOT BE SURPRISED TO SEE BREAKS IN THE CLOUDS WHICH
COULD ALLOW FOR A FEW LOCATIONS TO EXCEED 60 DEGREES.  RECORD HIGHS
FOR PITTSBURGH...MORGANTOWN...AND ZANESVILLE ALL RESIDE WELL INTO
THE UPPER 60S...SO AT THIS JUNCTURE RECORD WARMTH IS NOT FORESEEN.
PRECIP ASSOCIATED WITH THE SURFACE LOW PRESSURE SYSTEM EJECTING FROM
THE GULF COAST REGION REACHES SERN AREAS OF THE FORECAST AREA THAT
EVENING.

A BLEND OF THE ONGOING FORECAST AND BIAS CORRECTED ECMWF WERE USED
FOR TEMPERATURES.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
HIGHLIGHTS:
- A WET CHRISTMAS EVE
- TEMPERATURES RETURN BACK TO NORMAL VALUES CHRISTMAS DAY
- SLIGHTLY ABOVE NORMAL TEMPERATURES RETURN BY FRIDAY

STRONG LOW PRESSURE SYSTEM THAT HAS BEEN MUCH ADVERTISED GIVEN THE
TIME PERIOD WHICH IT AFFECTS OUR AREA IS STILL ON TRACK.  LONG RANGE
ENSEMBLE PREDICTION SYSTEMS AND OPERATIONAL MODELS ARE CONVERGING ON
A TRACK THROUGH IND / ILL THEN NORTH INTO CANADA.  THIS WILL MAKE
FOR ALL LIQUID PRECIPITATION ON THE FRONT END.  TEMPERATURES WILL
SOAR TO NEARLY 20 DEGREES ABOVE NORMAL WEDNESDAY WITH 50S COMMON.
COUPLED WITH INFLUX OF MOISTURE FROM THE GULF OF MEXICO...SOUNDINGS
ILLUSTRATE ELEVATED INSTABILITY WHICH PUSHES TEMP DIFFERENTIAL
BETWEEN H8 AND H5 TO NEARLY 0C.  THIS COULD LEAD TO ISOLATED
THUNDERSTORMS AHEAD OF THE BAROCLINIC ZONE.  FOR THE TIME
BEING...OPTED TO LEAVE THUNDER OUT OF THE FORECAST AND WAIT FOR
BETTER CONTINUITY GIVEN THIS STILL IS FIVE DAYS OUT.  DESPITE PWATS
NEARLY TWO STANDARD DEVIATIONS ABOVE NORMAL...COMBINATION OF
KATABATIC WINDS AND DRY CONVEYOR BELT WILL LIMIT QPF POTENTIAL TO
NEGATE ANY FLOOD THREAT.  LONG RANGE HYDROLOGIC MODELS SHOW VERY
LITTLE RISE IN AREA RIVERS...WHICH CORRELATES WELL TO THE PROJECTED
QPF OF 0.50 TO 1.00".

WITH THE TRACK OF THE CYCLONE DUE N...COLD AIR INJECTED INTO THE
AREA WILL BE OF MIDWEST ORIGIN...SO TEMPS WILL RETREAT BACK TO
SEASONAL BENCHMARKS CHRISTMAS DAY.  FOR THOSE WHO ARE LOOKING FOR
SNOW ON CHRISTMAS...A CHANCE OF SNOW SHOWERS EXIST...BUT GIVEN
TRAJECTORY FROM THE SOUTHWEST ANY ACCUMULATION ASSOCIATED WITH THE
UPPER LEVEL SYSTEM WILL BE LIGHT AT BEST.  HISTORICALLY...THERE IS
ONLY A 17 PERCENT CHANCE OF AT LEAST ONE INCH OF SNOW ON THE GROUND
AT PITTSBURGH CHRISTMAS MORNING.

H8 WINDS PUSH 50KTS WEDNESDAY NIGHT INTO THURSDAY AND HIGHEST
ANOMALIES RESIDE ALONG THE LAKE SHORE...SO EXPECT HIGHEST GUSTS
WOULD DO SO AS WELL.  NONETHELESS...PERIOD FROM WEDNESDAY NIGHT INTO
THURSDAY STRONG ISALLOBARIC FLOW COULD YIELD GUSTS IN EXCESS OF 40
MPH ESPECIALLY IN THE MOUNTAINS OF WRN MD AND NRN WV.

BALANCE OF THE EXTENDED IS CHARACTERIZED BY UNCERTAINTY AS ONE WOULD
EXPECT IN THE DAY 6 -7 TIME FRAME.  ECMWF HAS A STRONGER SYSTEM
CROSSING FRIDAY NIGHT VERSUS GFS WHICH IS MUCH WEAKER.  EITHER CASE
PTYPE SHOULD BE RAIN WITH SNOW SHOWERS ON THE BACKSIDE.  NO PLUNGES
OF ARCTIC AIR ARE FORECAST IN THE NEXT 10 DAYS.  MAX/MIN
TEMPERATURES WERE A BLEND OF THE FORECAST AND ECMWF BIAS CORRECTED
DATA SET.

&&

.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
WHILE FKL...DUJ...AND ZZV ARE EXPECTED TO REMAIN UNDER MVFR CIGS
OVERNIGHT...REMAINING TERMINALS MAY CONTINUE TO HAVE LOWER CLOUDS
SCATTER OUT LEAVING A MID DECK TEMPORARILY. BY MIDNIGHT ALL
TERMINALS ARE EXPECTED TO RETURN TO UNIFORM MVFR CIGS. CANNOT RULE
OUT SOME CIGS BELOW 2KFT BUT DID NOT HAVE CONFIDENCE TO INCLUDE
THEM. UNCERTAINTY REMAINS AS TO WHEN SKIES SHOULD SCATTER OUT ON
SUNDAY. THE SCATTERING TREND SHOULD MOVE FROM SOUTHWEST TO
NORTHEAST...BUT CURRENT FORECAST DOES NOT ELIMINATE CIG FROM
PITTSBURGH AND LOCATIONS NORTHEAST UNTIL 00Z MONDAY.


OUTLOOK.../SUNDAY NIGHT THROUGH THURSDAY/...
NEXT STORM SYSTEM WILL BEGIN TO IMPACT THE REGION ON TUESDAY AND
RESULT IN WIDESPREAD RAIN...CIG/VIS RESTRICTIONS...AND PERIODS OF
LLWS INTO THURSDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$






000
FXUS61 KPBZ 210217
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
917 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE WILL BE IN CONTROL INTO MONDAY. EXPECT INCREASING
PRECIPITATION CHANCES TUESDAY. STORM SYSTEM BRINGS RAIN AND WIND
CHRISTMAS EVE...AND SNOW SHOWERS CHRISTMAS DAY.

&&

.NEAR TERM /THROUGH SUNDAY/...
PRIMARY CHANGE WITH 915PM UPDATE WAS TO ADD SCATTERED FLURRIES
FROM PITTSBURGH AND TO THE NORTH AND WEST. SOME LIGHT RADAR ECHOES
HAVE MOVED FROM INDIANA INTO OHIO DURING THE AFTERNOON AND EARLY
EVENING HOURS...WITH A COUPLE OF AUTOMATED STATIONS REPORTING
LIGHT SNOW. IN THE LAST HOUR THREE SITES AROUND COLUMBUS OHIO HAVE
REPORTED SNOW...AND EXPECT THAT THIS FLURRY ACTIVITY COULD
CONTINUE AS IT IS ASSOCIATED WITH AN UPPER LEVEL SHORTWAVE MOVING
THROUGH THE REGION. FLURRIES SHOULD COME TO AN END AFTER MIDNIGHT.
A SLIGHT CHANCE OF LIGHT SNOW STILL CANNOT BE RULED OUT SOUTH AND
EAST OF PITTSBURGH WITH ANOTHER FEATURE...BUT NO ACCUMULATIONS ARE
EXPECTED ANYWHERE OVERNIGHT.

INVERSION IS MAINTAINED SUNDAY MORNING WHICH WILL MAINTAIN STRATUS
DECK...BUT BY AFTERNOON EXPECT STRATUS TO MIX OUT INTO A CU FIELD
AND THEN SCATTER OUT BY EVENING. A BIT MORE SUN SHOULD ALLOW FOR
AFTERNOON HIGH TEMPS AROUND 5 DEGREES WARMER THAN TODAY. CL

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
BENIGN WEATHER INITIALLY WITH HIGH PRESSURE TO OUR EAST AND IN
CONTROL.  SOUTHEAST WINDS IN RESPONSE TO SURFACE ANTICYCLONE
POSITION WILL FACILITATE DEVELOPMENT OF STRATUS OVER EASTERN
PORTIONS OF TUCKER AND GARRETT COUNTIES MONDAY INTO MONDAY NIGHT.
PCPN ONSET HAS SLOWED DOWN FROM PREVIOUS CYCLES...BUT THERE REMAINS
A VERY LOW PROBABILITY OF FREEZING RAIN AND/OR SLEET OVER
AFOREMENTIONED AREAS MONDAY.  FOR NOW...TRENDED FORECAST WITH PCPN
COMMENCING DURING THE AFTERNOON WHICH REFLECT LATEST NUMERICAL
MODELS.  WITH THIS SCENARIO...LOW LEVEL SUB-FREEZING AIR SHOULD
SCOUR OUT YIELDING AN ALL RAIN PTYPE.

RAIN SHADOW EFFECT TAKES PLACES TUESDAY WITH SOUTHEAST WINDS
WIDESPREAD OVER THE REGION. AN ISOLATED SHOWER REACHING EASTERN OHIO
AND FAR NWRN PA IS NOT OUT OF THE QUESTION...SO KEPT A SLIGHT
CHANCE.  WOULD NOT BE SURPRISED TO SEE BREAKS IN THE CLOUDS WHICH
COULD ALLOW FOR A FEW LOCATIONS TO EXCEED 60 DEGREES.  RECORD HIGHS
FOR PITTSBURGH...MORGANTOWN...AND ZANESVILLE ALL RESIDE WELL INTO
THE UPPER 60S...SO AT THIS JUNCTURE RECORD WARMTH IS NOT FORESEEN.
PRECIP ASSOCIATED WITH THE SURFACE LOW PRESSURE SYSTEM EJECTING FROM
THE GULF COAST REGION REACHES SERN AREAS OF THE FORECAST AREA THAT
EVENING.

A BLEND OF THE ONGOING FORECAST AND BIAS CORRECTED ECMWF WERE USED
FOR TEMPERATURES.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
HIGHLIGHTS:
- A WET CHRISTMAS EVE
- TEMPERATURES RETURN BACK TO NORMAL VALUES CHRISTMAS DAY
- SLIGHTLY ABOVE NORMAL TEMPERATURES RETURN BY FRIDAY

STRONG LOW PRESSURE SYSTEM THAT HAS BEEN MUCH ADVERTISED GIVEN THE
TIME PERIOD WHICH IT AFFECTS OUR AREA IS STILL ON TRACK.  LONG RANGE
ENSEMBLE PREDICTION SYSTEMS AND OPERATIONAL MODELS ARE CONVERGING ON
A TRACK THROUGH IND / ILL THEN NORTH INTO CANADA.  THIS WILL MAKE
FOR ALL LIQUID PRECIPITATION ON THE FRONT END.  TEMPERATURES WILL
SOAR TO NEARLY 20 DEGREES ABOVE NORMAL WEDNESDAY WITH 50S COMMON.
COUPLED WITH INFLUX OF MOISTURE FROM THE GULF OF MEXICO...SOUNDINGS
ILLUSTRATE ELEVATED INSTABILITY WHICH PUSHES TEMP DIFFERENTIAL
BETWEEN H8 AND H5 TO NEARLY 0C.  THIS COULD LEAD TO ISOLATED
THUNDERSTORMS AHEAD OF THE BAROCLINIC ZONE.  FOR THE TIME
BEING...OPTED TO LEAVE THUNDER OUT OF THE FORECAST AND WAIT FOR
BETTER CONTINUITY GIVEN THIS STILL IS FIVE DAYS OUT.  DESPITE PWATS
NEARLY TWO STANDARD DEVIATIONS ABOVE NORMAL...COMBINATION OF
KATABATIC WINDS AND DRY CONVEYOR BELT WILL LIMIT QPF POTENTIAL TO
NEGATE ANY FLOOD THREAT.  LONG RANGE HYDROLOGIC MODELS SHOW VERY
LITTLE RISE IN AREA RIVERS...WHICH CORRELATES WELL TO THE PROJECTED
QPF OF 0.50 TO 1.00".

WITH THE TRACK OF THE CYCLONE DUE N...COLD AIR INJECTED INTO THE
AREA WILL BE OF MIDWEST ORIGIN...SO TEMPS WILL RETREAT BACK TO
SEASONAL BENCHMARKS CHRISTMAS DAY.  FOR THOSE WHO ARE LOOKING FOR
SNOW ON CHRISTMAS...A CHANCE OF SNOW SHOWERS EXIST...BUT GIVEN
TRAJECTORY FROM THE SOUTHWEST ANY ACCUMULATION ASSOCIATED WITH THE
UPPER LEVEL SYSTEM WILL BE LIGHT AT BEST.  HISTORICALLY...THERE IS
ONLY A 17 PERCENT CHANCE OF AT LEAST ONE INCH OF SNOW ON THE GROUND
AT PITTSBURGH CHRISTMAS MORNING.

H8 WINDS PUSH 50KTS WEDNESDAY NIGHT INTO THURSDAY AND HIGHEST
ANOMALIES RESIDE ALONG THE LAKE SHORE...SO EXPECT HIGHEST GUSTS
WOULD DO SO AS WELL.  NONETHELESS...PERIOD FROM WEDNESDAY NIGHT INTO
THURSDAY STRONG ISALLOBARIC FLOW COULD YIELD GUSTS IN EXCESS OF 40
MPH ESPECIALLY IN THE MOUNTAINS OF WRN MD AND NRN WV.

BALANCE OF THE EXTENDED IS CHARACTERIZED BY UNCERTAINTY AS ONE WOULD
EXPECT IN THE DAY 6 -7 TIME FRAME.  ECMWF HAS A STRONGER SYSTEM
CROSSING FRIDAY NIGHT VERSUS GFS WHICH IS MUCH WEAKER.  EITHER CASE
PTYPE SHOULD BE RAIN WITH SNOW SHOWERS ON THE BACKSIDE.  NO PLUNGES
OF ARCTIC AIR ARE FORECAST IN THE NEXT 10 DAYS.  MAX/MIN
TEMPERATURES WERE A BLEND OF THE FORECAST AND ECMWF BIAS CORRECTED
DATA SET.

&&

.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
WHILE FKL...DUJ...AND ZZV ARE EXPECTED TO REMAIN UNDER MVFR CIGS
OVERNIGHT...REMAINING TERMINALS MAY CONTINUE TO HAVE LOWER CLOUDS
SCATTER OUT LEAVING A MID DECK TEMPORARILY. BY MIDNIGHT ALL
TERMINALS ARE EXPECTED TO RETURN TO UNIFORM MVFR CIGS. CANNOT RULE
OUT SOME CIGS BELOW 2KFT BUT DID NOT HAVE CONFIDENCE TO INCLUDE
THEM. UNCERTAINTY REMAINS AS TO WHEN SKIES SHOULD SCATTER OUT ON
SUNDAY. THE SCATTERING TREND SHOULD MOVE FROM SOUTHWEST TO
NORTHEAST...BUT CURRENT FORECAST DOES NOT ELIMINATE CIG FROM
PITTSBURGH AND LOCATIONS NORTHEAST UNTIL 00Z MONDAY.


OUTLOOK.../SUNDAY NIGHT THROUGH THURSDAY/...
NEXT STORM SYSTEM WILL BEGIN TO IMPACT THE REGION ON TUESDAY AND
RESULT IN WIDESPREAD RAIN...CIG/VIS RESTRICTIONS...AND PERIODS OF
LLWS INTO THURSDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$





  [top]

000
FXUS61 KPHI 210216
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
916 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE WILL SLOWLY BUILD SOUTHWESTWARD INTO THE REGION
FROM ATLANTIC CANADA THROUGH MONDAY. LOW PRESSURE WILL ORGANIZE
OFF THE CAROLINAS MONDAY NIGHT AND MOVE NORTHEASTWARD OFFSHORE ON
TUESDAY. MEANWHILE...ANOTHER AREA OF LOW PRESSURE WILL DEVELOP
OVER THE OHIO VALLEY AND MOVE NORTHWARD INTO QUEBEC...LEADING TO A
STRONG COLD FRONTAL PASSAGE ON THURSDAY NIGHT. HIGH PRESSURE WILL
BUILD IN ON FRIDAY AND A WEAKER COLD FRONT MAY APPROACH THE REGION
NEXT WEEKEND.

&&

.NEAR TERM /THROUGH SUNDAY/...
WEAK SURFACE HIGH PRESSURE WILL REMAIN ACROSS THE AREA TONIGHT.
PLENTY OF MOISTURE REMAINS TRAPPED BELOW A LOW LEVEL INVERSION,
ESPECIALLY PHILLY NORTH. THE LOW CLOUDS HAVE BROKEN UP SOUTH OF
PHILLY, BUT SKIES WILL FILL UP AGAIN AS A MID-LEVEL DECK ADVECTS
IN OVERNIGHT. THESE CLOUDS ARE ASSOCIATED WITH A MID-LEVEL SHORT
WAVE.

THE HIGH RESOLUTION MODELS KEEP THE CWA PRECIP-FREE(MEASURABLE)
THROUGH THE OVERNIGHT AS DOES THE LOWER RES MODELS. WE`LL KEEP THE
GRIDS AS IS, BUT CAN`T RULE OUT A FLURRY OR TWO UP ACROSS THE
NORTHERN THIRD OF THE CWA.

ANOTHER SEASONABLY COLD NIGHT IS EXPECTED WITH LOWS IN THE LOW 20S
NORTH AND MID OR UPPER 20S SOUTH. WINDS WILL BE LIGHT FROM THE
NORTH.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH 6 PM SUNDAY/...
AFTER A WEAK SHORTWAVE CROSSES THE AREA SUN MORNING...UPPER RIDGING
WILL TAKE PLACE. THIS WILL HOPEFULLY ALLOW MORE SUNSHINE ACROSS THE
AREA. WE HAVE WRITTEN A PARTLY TO MOSTLY SUNNY FCST FOR NOW. WE HELD
ONTO SOME EXTRA CLOUD COVER ACROSS THE SRN POCONOS HOWEVER. HIGH
TEMPERATURES SUNDAY WILL RISE INTO THE LOW 40S ACROSS SRN NJ AND THE
DELMARVA...WHILE READINGS HOLD IN THE MID/UPPER 30S ACROSS THE
NORTH/WEST AREAS. WINDS WILL REMAIN LIGHT...MOSTLY FROM THE NORTH.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
HIGHLIGHTS...

* FREEZING RAIN POSSIBLE MONDAY NIGHT OVER THE NORTHWEST.
* INCREASING POTENTIAL FOR HEAVY RAIN CHRISTMAS EVE WITH
  TEMPERATURES WELL ABOVE NORMAL.
* BRISK WESTERLY WIND CHRISTMAS DAY W/FLURRIES POSSIBLE.

OVERVIEW...

VIGOROUS MID-LEVEL DISTURBANCE AND ACCOMPANYING 160 KNOT UPPER-LEVEL
JET MAX COMING ASHORE OVER THE PACIFIC NORTHWEST LATE THIS WEEKEND
WILL LEAD TO A DEEP TROUGH OVER THE MISSISSIPPI VALLEY BY MID-WEEK.
INITIAL PIECE OF ENERGY AHEAD OF THIS TROUGH IS EJECTED NORTHEAST
AND WILL LEAD TO THE DEVELOPMENT OF AN AREA OF LOW-PRESSURE OFF THE
CAROLINAS ON MONDAY. THIS WEAK FEATURE SHOULD TRACK OFFSHORE WELL
SOUTHEAST OF THE REGION ON TUESDAY PER TODAYS 12Z UKMET AND GFS...
FEEL THE NAM AND ECMWF ARE TOO FAR NORTH, SLOW, AND DEEP W/THIS
FEATURE...THUS THEY ALSO CRANK OUT TOO MUCH QPF. NEVERTHELESS...
QPF COMBINED WITH MARGINAL TEMPERATURE PROFILES OVER THE NORTHWEST
COULD SUPPORT SOME LIGHT FREEZING RAIN MONDAY NIGHT. MID-LEVEL FLOW
THEN BECOMES INCREASINGLY MERIDIONAL...PUMPING ANOMALOUSLY WARM
AND MOIST AIR UP THE EAST COAST...SETTING THE STAGE FOR HEAVY RAIN
ON CHRISTMAS EVE DAY. THE TROUGH LOOKS TO BECOME NEGATIVELY TILTED
AS IT CROSSES THE REGION...LEADING TO A STRONG FRONTAL PASSAGE LATE
WEDNESDAY INTO EARLY THURSDAY...WITH SOME FLURRIES POSSIBLE ON THE
BACK-SIDE OF THE STORM SYSTEM.

DETAILS...

MONDAY...
MID-LEVEL RIDGE CRESTS OVER THE REGION EARLY IN THE DAY...W/SURFACE
HIGH ANCHORED ALONG THE EAST COAST IN A COLD-AIR DAMMING SIGNATURE.
PRECIPITATION WILL BE LARGELY DRIVEN BY INSENTROPIC ASCENT OVER THE
COLDER LOW-LEVEL AIRMASS AND WILL BEGIN LATE IN THE DAY AS MOISTURE
STREAMS IN ALOFT AND LOW-LEVELS GRADUALLY SATURATE. THERE MAY BE A
PERIOD OF LIGHT FREEZING RAIN OVER THE NORTHWEST AS A COLD AIR
IS REINFORCED W/NORTHERLY SURFACE WINDS AND PRECIP LEADS TO
EVAPORATIONAL COOLING.

TUESDAY...
ANY LIGHT FREEZING RAIN SHOULD END EARLY IN THE MORNING WITH STRONG
WARM AIR ADVECTION ALOFT. ALTHOUGH THE BEST FORCING REMAINS WELL TO
THE WEST...BROAD ISENTROPIC ASCENT AND INCREASING MOISTURE SHOULD
LEAD TO SCATTERED RAIN SHOWERS THRU THE DAY. QPF SHOULD BE GENERALLY
LIGHT.

WEDNESDAY...
A VIGOROUS TROUGH APPROACHES FROM THE WEST W/STILL SOME SPREAD NOTED
FROM THE MEAN IN BOTH THE ECENS AND GEFS 500 HPA HEIGHT FIELDS...
INDICATING SOME DISAGREEMENT WITH REGARD TO WHAT DEGREE IT GOES
NEGATIVELY TILTED. NEVERTHELESS...A VERY DYNAMIC SYSTEM WITH SEVERAL
INGREDIENTS COMING TOGETHER FOR UP TO 1-2 INCHES OF QPF...ESPECIALLY
OVER THE HIGHER TERRAIN. NOTING A STRONG MID-LEVEL VORT MAX AND THE
LEFT-FRONT QUADRANT OF A 160 KNOT UPPER-LEVEL JET TRAVERSING THE
APPALACHIANS. ALSO NOTING STRONG WARM AIR ADVECTION AND ANOMALOUSLY
HIGH /2-3 STANDARD DEVIATION/ PRECIPITABLE WATER VALUES STREAMING
UP THE EASTERN SEABOARD. THUS THERE IS PLENTY OF MOISTURE AND
ASCENT FOR HEAVY RAINFALL...W/THE MODELS KEYING IN ON WEDNESDAY
AFTERNOON AND WEDNESDAY NIGHT FOR THE BULK OF THE PRECIP...AND
THIS WILL NEED TO BE MONITORED FOR FLOODING POTENTIAL PARTICULARLY
DUE TO THE HOLIDAY TRAVEL CHRISTMAS EVE. LATER SHIFTS WILL ALSO
NEED TO FURTHER EVALUATE THE POTENTIAL FOR GUSTY SURFACE WINDS
AND CONVECTION.

THURSDAY AND FRIDAY...
LOW-PRESSURE MOVES NORTHWARD INTO QUEBEC AND HIGH-PRESSURE BEGINS TO
BUILD IN. TEMPERATURES WILL REMAIN ABOVE SEASONABLE LEVELS AND THERE
COULD BE SNOW SHOWERS IN THE BLUSTERY NORTHWEST FLOW ON THURSDAY...
PARTICULARLY NORTHWEST.

SATURDAY...ANOTHER COLD FRONT MAY APPROACH THE REGION...BUT IT/S TOO
EARLY TO SPECULATE...ESPECIALLY GIVEN THE UNCERTAINTY THAT THE STORM
SYSTEM MOVING THROUGH THE NORTHEAST CONUS MID-WEEK COULD ADD TO THE
FORECAST.

&&

.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

THERE HAS BEEN PLENTY OF LOW LEVEL MOISTURE TRAPPED BELOW THE
INVERSION AGAIN TODAY. CIGS WERE BETWEEN 025-035 ACROSS THE AREA
THIS AFTERNOON. THIS EVENING WE`RE SEEING MORE 030-035. STILL,
MOSTLY IN THE NORTH QUADRANT.

WE`LL KEEP THE LOW CLOUDS IN THE TERMINALS FROM KPHL NORTHWARD
THROUGH THE NIGHT. TO THE SOUTH, WE`VE SCATTERED THE LOW LEVEL
DECK OUT. A SHORT WAVE WILL BRING SOME ALTOCU TO JUST ABOUT
EVERYWHERE OVERNIGHT.

WINDS WILL REMAIN LIGHT OVERNIGHT. NO PRECIPITATION HAS BEEN
MENTIONED.

OUTLOOK...

SUNDAY NIGHT AND MONDAY MORNING...VFR.

MONDAY AFTERNOON...POTENTIAL FOR MVFR CIGS AS MARINE LAYER BECOMES
ESTABLISHED AND STRATUS ADVECTS INLAND.

MONDAY NIGHT THROUGH TUESDAY NIGHT...THE COMBINATION OF
STRENGTHENING ONSHORE FLOW AND IN-SITU CAD FROM LIGHT RAIN
OVERSPREADING THE TERMINALS COULD YIELD AN EXTENDED PERIOD OF
MVFR/IFR CONDITIONS (CIGS WOULD BE THE MORE LIKELY CONTRIBUTOR TO
IFR THAN VSBYS) MONDAY NIGHT INTO TUESDAY.

WEDNESDAY...WINDS VEER MORE OUT OF THE SOUTH AS A WARM FRONT SLOWLY
LIFTS NORTHWARD. RAIN IS EXPECTED TO BE THE MOST WIDESPREAD AND
HEAVIEST DURING THIS PART OF THE FORECAST PERIOD. PREDOMINATELY MVFR
AND IFR CONDITIONS. SOUTHERLY WINDS WILL BECOME BREEZY FOLLOWING
WARM FROPA.

WEDNESDAY NIGHT...COLD FRONT IS FORECAST TO MOVE THRU SOMETIME AT
NIGHT. LOW CLOUDS AND RAIN WILL END FROM WEST TO EAST IN WAKE OF
FROPA.

THURSDAY...WESTERLY WINDS COULD BECOME STRONG BEHIND THE FRONT
THURSDAY WITH BUFKIT FORECAST SOUNDINGS FROM THE 12Z GFS SHOWING THE
POTENTIAL FOR 30-40 KT GUSTS.

&&

.MARINE...
WEAK HIGH PRESSURE WILL REMAIN ACROSS THE WATERS TONIGHT AND SUNDAY.
WINDS AND SEAS WILL REMAIN BELOW SCA FLAG CRITERIA. WINDS WILL
MOSTLY BE NORTHERLY THROUGH THE PERIOD.

OUTLOOK...
SUNDAY NIGHT THROUGH MONDAY NIGHT...WINDS AND SEAS BELOW SCA
CRITERIA.

TUESDAY AND TUESDAY NIGHT...ONSHORE FLOW STRENGTHENS ON TUESDAY.
WINDS 15-20 KT FORECAST ON TUESDAY. SEAS ARE FORECAST TO BUILD TO
5-6 FEET TUESDAY AND TUESDAY NIGHT, WARRANTING THE NEED FOR A SCA.

WEDNESDAY AND WEDNESDAY NIGHT...SOUTHERLY WINDS STRENGTHEN AFTER
WARM FROPA. DESPITE WINDS OF 40-50 KT FORECAST 1000 FT ABOVE THE
SURFACE, THERMAL PROFILES NOT FAVORABLE FOR MIXING WITH THE SETUP OF
WARM AIR MOVING ATOP THE COOLER WATERS. EXPECTING MORE OF A HIGH END
SCA WITH 25-30 KT WINDS. WINDS FORECAST TO BECOME WESTERLY LATE
WEDNESDAY NIGHT BEHIND A COLD FRONT BUT THE CORE OF THE COLD AIR
WILL STILL REMAIN UPSTREAM OF THE WATERS. SEAS FORECAST TO INCREASE
TO 6-8 FEET.

THURSDAY...GUSTY WESTERLY WINDS EXPECTED. GALES CERTAINLY A
POSSIBILITY.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANCK
NEAR TERM...O`HARA
SHORT TERM...O`HARA
LONG TERM...FRANCK
AVIATION...FRANCK/KLEIN/O`HARA
MARINE...KLEIN/O`HARA







000
FXUS61 KPHI 210216
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
916 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE WILL SLOWLY BUILD SOUTHWESTWARD INTO THE REGION
FROM ATLANTIC CANADA THROUGH MONDAY. LOW PRESSURE WILL ORGANIZE
OFF THE CAROLINAS MONDAY NIGHT AND MOVE NORTHEASTWARD OFFSHORE ON
TUESDAY. MEANWHILE...ANOTHER AREA OF LOW PRESSURE WILL DEVELOP
OVER THE OHIO VALLEY AND MOVE NORTHWARD INTO QUEBEC...LEADING TO A
STRONG COLD FRONTAL PASSAGE ON THURSDAY NIGHT. HIGH PRESSURE WILL
BUILD IN ON FRIDAY AND A WEAKER COLD FRONT MAY APPROACH THE REGION
NEXT WEEKEND.

&&

.NEAR TERM /THROUGH SUNDAY/...
WEAK SURFACE HIGH PRESSURE WILL REMAIN ACROSS THE AREA TONIGHT.
PLENTY OF MOISTURE REMAINS TRAPPED BELOW A LOW LEVEL INVERSION,
ESPECIALLY PHILLY NORTH. THE LOW CLOUDS HAVE BROKEN UP SOUTH OF
PHILLY, BUT SKIES WILL FILL UP AGAIN AS A MID-LEVEL DECK ADVECTS
IN OVERNIGHT. THESE CLOUDS ARE ASSOCIATED WITH A MID-LEVEL SHORT
WAVE.

THE HIGH RESOLUTION MODELS KEEP THE CWA PRECIP-FREE(MEASURABLE)
THROUGH THE OVERNIGHT AS DOES THE LOWER RES MODELS. WE`LL KEEP THE
GRIDS AS IS, BUT CAN`T RULE OUT A FLURRY OR TWO UP ACROSS THE
NORTHERN THIRD OF THE CWA.

ANOTHER SEASONABLY COLD NIGHT IS EXPECTED WITH LOWS IN THE LOW 20S
NORTH AND MID OR UPPER 20S SOUTH. WINDS WILL BE LIGHT FROM THE
NORTH.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH 6 PM SUNDAY/...
AFTER A WEAK SHORTWAVE CROSSES THE AREA SUN MORNING...UPPER RIDGING
WILL TAKE PLACE. THIS WILL HOPEFULLY ALLOW MORE SUNSHINE ACROSS THE
AREA. WE HAVE WRITTEN A PARTLY TO MOSTLY SUNNY FCST FOR NOW. WE HELD
ONTO SOME EXTRA CLOUD COVER ACROSS THE SRN POCONOS HOWEVER. HIGH
TEMPERATURES SUNDAY WILL RISE INTO THE LOW 40S ACROSS SRN NJ AND THE
DELMARVA...WHILE READINGS HOLD IN THE MID/UPPER 30S ACROSS THE
NORTH/WEST AREAS. WINDS WILL REMAIN LIGHT...MOSTLY FROM THE NORTH.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
HIGHLIGHTS...

* FREEZING RAIN POSSIBLE MONDAY NIGHT OVER THE NORTHWEST.
* INCREASING POTENTIAL FOR HEAVY RAIN CHRISTMAS EVE WITH
  TEMPERATURES WELL ABOVE NORMAL.
* BRISK WESTERLY WIND CHRISTMAS DAY W/FLURRIES POSSIBLE.

OVERVIEW...

VIGOROUS MID-LEVEL DISTURBANCE AND ACCOMPANYING 160 KNOT UPPER-LEVEL
JET MAX COMING ASHORE OVER THE PACIFIC NORTHWEST LATE THIS WEEKEND
WILL LEAD TO A DEEP TROUGH OVER THE MISSISSIPPI VALLEY BY MID-WEEK.
INITIAL PIECE OF ENERGY AHEAD OF THIS TROUGH IS EJECTED NORTHEAST
AND WILL LEAD TO THE DEVELOPMENT OF AN AREA OF LOW-PRESSURE OFF THE
CAROLINAS ON MONDAY. THIS WEAK FEATURE SHOULD TRACK OFFSHORE WELL
SOUTHEAST OF THE REGION ON TUESDAY PER TODAYS 12Z UKMET AND GFS...
FEEL THE NAM AND ECMWF ARE TOO FAR NORTH, SLOW, AND DEEP W/THIS
FEATURE...THUS THEY ALSO CRANK OUT TOO MUCH QPF. NEVERTHELESS...
QPF COMBINED WITH MARGINAL TEMPERATURE PROFILES OVER THE NORTHWEST
COULD SUPPORT SOME LIGHT FREEZING RAIN MONDAY NIGHT. MID-LEVEL FLOW
THEN BECOMES INCREASINGLY MERIDIONAL...PUMPING ANOMALOUSLY WARM
AND MOIST AIR UP THE EAST COAST...SETTING THE STAGE FOR HEAVY RAIN
ON CHRISTMAS EVE DAY. THE TROUGH LOOKS TO BECOME NEGATIVELY TILTED
AS IT CROSSES THE REGION...LEADING TO A STRONG FRONTAL PASSAGE LATE
WEDNESDAY INTO EARLY THURSDAY...WITH SOME FLURRIES POSSIBLE ON THE
BACK-SIDE OF THE STORM SYSTEM.

DETAILS...

MONDAY...
MID-LEVEL RIDGE CRESTS OVER THE REGION EARLY IN THE DAY...W/SURFACE
HIGH ANCHORED ALONG THE EAST COAST IN A COLD-AIR DAMMING SIGNATURE.
PRECIPITATION WILL BE LARGELY DRIVEN BY INSENTROPIC ASCENT OVER THE
COLDER LOW-LEVEL AIRMASS AND WILL BEGIN LATE IN THE DAY AS MOISTURE
STREAMS IN ALOFT AND LOW-LEVELS GRADUALLY SATURATE. THERE MAY BE A
PERIOD OF LIGHT FREEZING RAIN OVER THE NORTHWEST AS A COLD AIR
IS REINFORCED W/NORTHERLY SURFACE WINDS AND PRECIP LEADS TO
EVAPORATIONAL COOLING.

TUESDAY...
ANY LIGHT FREEZING RAIN SHOULD END EARLY IN THE MORNING WITH STRONG
WARM AIR ADVECTION ALOFT. ALTHOUGH THE BEST FORCING REMAINS WELL TO
THE WEST...BROAD ISENTROPIC ASCENT AND INCREASING MOISTURE SHOULD
LEAD TO SCATTERED RAIN SHOWERS THRU THE DAY. QPF SHOULD BE GENERALLY
LIGHT.

WEDNESDAY...
A VIGOROUS TROUGH APPROACHES FROM THE WEST W/STILL SOME SPREAD NOTED
FROM THE MEAN IN BOTH THE ECENS AND GEFS 500 HPA HEIGHT FIELDS...
INDICATING SOME DISAGREEMENT WITH REGARD TO WHAT DEGREE IT GOES
NEGATIVELY TILTED. NEVERTHELESS...A VERY DYNAMIC SYSTEM WITH SEVERAL
INGREDIENTS COMING TOGETHER FOR UP TO 1-2 INCHES OF QPF...ESPECIALLY
OVER THE HIGHER TERRAIN. NOTING A STRONG MID-LEVEL VORT MAX AND THE
LEFT-FRONT QUADRANT OF A 160 KNOT UPPER-LEVEL JET TRAVERSING THE
APPALACHIANS. ALSO NOTING STRONG WARM AIR ADVECTION AND ANOMALOUSLY
HIGH /2-3 STANDARD DEVIATION/ PRECIPITABLE WATER VALUES STREAMING
UP THE EASTERN SEABOARD. THUS THERE IS PLENTY OF MOISTURE AND
ASCENT FOR HEAVY RAINFALL...W/THE MODELS KEYING IN ON WEDNESDAY
AFTERNOON AND WEDNESDAY NIGHT FOR THE BULK OF THE PRECIP...AND
THIS WILL NEED TO BE MONITORED FOR FLOODING POTENTIAL PARTICULARLY
DUE TO THE HOLIDAY TRAVEL CHRISTMAS EVE. LATER SHIFTS WILL ALSO
NEED TO FURTHER EVALUATE THE POTENTIAL FOR GUSTY SURFACE WINDS
AND CONVECTION.

THURSDAY AND FRIDAY...
LOW-PRESSURE MOVES NORTHWARD INTO QUEBEC AND HIGH-PRESSURE BEGINS TO
BUILD IN. TEMPERATURES WILL REMAIN ABOVE SEASONABLE LEVELS AND THERE
COULD BE SNOW SHOWERS IN THE BLUSTERY NORTHWEST FLOW ON THURSDAY...
PARTICULARLY NORTHWEST.

SATURDAY...ANOTHER COLD FRONT MAY APPROACH THE REGION...BUT IT/S TOO
EARLY TO SPECULATE...ESPECIALLY GIVEN THE UNCERTAINTY THAT THE STORM
SYSTEM MOVING THROUGH THE NORTHEAST CONUS MID-WEEK COULD ADD TO THE
FORECAST.

&&

.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

THERE HAS BEEN PLENTY OF LOW LEVEL MOISTURE TRAPPED BELOW THE
INVERSION AGAIN TODAY. CIGS WERE BETWEEN 025-035 ACROSS THE AREA
THIS AFTERNOON. THIS EVENING WE`RE SEEING MORE 030-035. STILL,
MOSTLY IN THE NORTH QUADRANT.

WE`LL KEEP THE LOW CLOUDS IN THE TERMINALS FROM KPHL NORTHWARD
THROUGH THE NIGHT. TO THE SOUTH, WE`VE SCATTERED THE LOW LEVEL
DECK OUT. A SHORT WAVE WILL BRING SOME ALTOCU TO JUST ABOUT
EVERYWHERE OVERNIGHT.

WINDS WILL REMAIN LIGHT OVERNIGHT. NO PRECIPITATION HAS BEEN
MENTIONED.

OUTLOOK...

SUNDAY NIGHT AND MONDAY MORNING...VFR.

MONDAY AFTERNOON...POTENTIAL FOR MVFR CIGS AS MARINE LAYER BECOMES
ESTABLISHED AND STRATUS ADVECTS INLAND.

MONDAY NIGHT THROUGH TUESDAY NIGHT...THE COMBINATION OF
STRENGTHENING ONSHORE FLOW AND IN-SITU CAD FROM LIGHT RAIN
OVERSPREADING THE TERMINALS COULD YIELD AN EXTENDED PERIOD OF
MVFR/IFR CONDITIONS (CIGS WOULD BE THE MORE LIKELY CONTRIBUTOR TO
IFR THAN VSBYS) MONDAY NIGHT INTO TUESDAY.

WEDNESDAY...WINDS VEER MORE OUT OF THE SOUTH AS A WARM FRONT SLOWLY
LIFTS NORTHWARD. RAIN IS EXPECTED TO BE THE MOST WIDESPREAD AND
HEAVIEST DURING THIS PART OF THE FORECAST PERIOD. PREDOMINATELY MVFR
AND IFR CONDITIONS. SOUTHERLY WINDS WILL BECOME BREEZY FOLLOWING
WARM FROPA.

WEDNESDAY NIGHT...COLD FRONT IS FORECAST TO MOVE THRU SOMETIME AT
NIGHT. LOW CLOUDS AND RAIN WILL END FROM WEST TO EAST IN WAKE OF
FROPA.

THURSDAY...WESTERLY WINDS COULD BECOME STRONG BEHIND THE FRONT
THURSDAY WITH BUFKIT FORECAST SOUNDINGS FROM THE 12Z GFS SHOWING THE
POTENTIAL FOR 30-40 KT GUSTS.

&&

.MARINE...
WEAK HIGH PRESSURE WILL REMAIN ACROSS THE WATERS TONIGHT AND SUNDAY.
WINDS AND SEAS WILL REMAIN BELOW SCA FLAG CRITERIA. WINDS WILL
MOSTLY BE NORTHERLY THROUGH THE PERIOD.

OUTLOOK...
SUNDAY NIGHT THROUGH MONDAY NIGHT...WINDS AND SEAS BELOW SCA
CRITERIA.

TUESDAY AND TUESDAY NIGHT...ONSHORE FLOW STRENGTHENS ON TUESDAY.
WINDS 15-20 KT FORECAST ON TUESDAY. SEAS ARE FORECAST TO BUILD TO
5-6 FEET TUESDAY AND TUESDAY NIGHT, WARRANTING THE NEED FOR A SCA.

WEDNESDAY AND WEDNESDAY NIGHT...SOUTHERLY WINDS STRENGTHEN AFTER
WARM FROPA. DESPITE WINDS OF 40-50 KT FORECAST 1000 FT ABOVE THE
SURFACE, THERMAL PROFILES NOT FAVORABLE FOR MIXING WITH THE SETUP OF
WARM AIR MOVING ATOP THE COOLER WATERS. EXPECTING MORE OF A HIGH END
SCA WITH 25-30 KT WINDS. WINDS FORECAST TO BECOME WESTERLY LATE
WEDNESDAY NIGHT BEHIND A COLD FRONT BUT THE CORE OF THE COLD AIR
WILL STILL REMAIN UPSTREAM OF THE WATERS. SEAS FORECAST TO INCREASE
TO 6-8 FEET.

THURSDAY...GUSTY WESTERLY WINDS EXPECTED. GALES CERTAINLY A
POSSIBILITY.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANCK
NEAR TERM...O`HARA
SHORT TERM...O`HARA
LONG TERM...FRANCK
AVIATION...FRANCK/KLEIN/O`HARA
MARINE...KLEIN/O`HARA







000
FXUS61 KPHI 210216
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
916 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE WILL SLOWLY BUILD SOUTHWESTWARD INTO THE REGION
FROM ATLANTIC CANADA THROUGH MONDAY. LOW PRESSURE WILL ORGANIZE
OFF THE CAROLINAS MONDAY NIGHT AND MOVE NORTHEASTWARD OFFSHORE ON
TUESDAY. MEANWHILE...ANOTHER AREA OF LOW PRESSURE WILL DEVELOP
OVER THE OHIO VALLEY AND MOVE NORTHWARD INTO QUEBEC...LEADING TO A
STRONG COLD FRONTAL PASSAGE ON THURSDAY NIGHT. HIGH PRESSURE WILL
BUILD IN ON FRIDAY AND A WEAKER COLD FRONT MAY APPROACH THE REGION
NEXT WEEKEND.

&&

.NEAR TERM /THROUGH SUNDAY/...
WEAK SURFACE HIGH PRESSURE WILL REMAIN ACROSS THE AREA TONIGHT.
PLENTY OF MOISTURE REMAINS TRAPPED BELOW A LOW LEVEL INVERSION,
ESPECIALLY PHILLY NORTH. THE LOW CLOUDS HAVE BROKEN UP SOUTH OF
PHILLY, BUT SKIES WILL FILL UP AGAIN AS A MID-LEVEL DECK ADVECTS
IN OVERNIGHT. THESE CLOUDS ARE ASSOCIATED WITH A MID-LEVEL SHORT
WAVE.

THE HIGH RESOLUTION MODELS KEEP THE CWA PRECIP-FREE(MEASURABLE)
THROUGH THE OVERNIGHT AS DOES THE LOWER RES MODELS. WE`LL KEEP THE
GRIDS AS IS, BUT CAN`T RULE OUT A FLURRY OR TWO UP ACROSS THE
NORTHERN THIRD OF THE CWA.

ANOTHER SEASONABLY COLD NIGHT IS EXPECTED WITH LOWS IN THE LOW 20S
NORTH AND MID OR UPPER 20S SOUTH. WINDS WILL BE LIGHT FROM THE
NORTH.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH 6 PM SUNDAY/...
AFTER A WEAK SHORTWAVE CROSSES THE AREA SUN MORNING...UPPER RIDGING
WILL TAKE PLACE. THIS WILL HOPEFULLY ALLOW MORE SUNSHINE ACROSS THE
AREA. WE HAVE WRITTEN A PARTLY TO MOSTLY SUNNY FCST FOR NOW. WE HELD
ONTO SOME EXTRA CLOUD COVER ACROSS THE SRN POCONOS HOWEVER. HIGH
TEMPERATURES SUNDAY WILL RISE INTO THE LOW 40S ACROSS SRN NJ AND THE
DELMARVA...WHILE READINGS HOLD IN THE MID/UPPER 30S ACROSS THE
NORTH/WEST AREAS. WINDS WILL REMAIN LIGHT...MOSTLY FROM THE NORTH.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
HIGHLIGHTS...

* FREEZING RAIN POSSIBLE MONDAY NIGHT OVER THE NORTHWEST.
* INCREASING POTENTIAL FOR HEAVY RAIN CHRISTMAS EVE WITH
  TEMPERATURES WELL ABOVE NORMAL.
* BRISK WESTERLY WIND CHRISTMAS DAY W/FLURRIES POSSIBLE.

OVERVIEW...

VIGOROUS MID-LEVEL DISTURBANCE AND ACCOMPANYING 160 KNOT UPPER-LEVEL
JET MAX COMING ASHORE OVER THE PACIFIC NORTHWEST LATE THIS WEEKEND
WILL LEAD TO A DEEP TROUGH OVER THE MISSISSIPPI VALLEY BY MID-WEEK.
INITIAL PIECE OF ENERGY AHEAD OF THIS TROUGH IS EJECTED NORTHEAST
AND WILL LEAD TO THE DEVELOPMENT OF AN AREA OF LOW-PRESSURE OFF THE
CAROLINAS ON MONDAY. THIS WEAK FEATURE SHOULD TRACK OFFSHORE WELL
SOUTHEAST OF THE REGION ON TUESDAY PER TODAYS 12Z UKMET AND GFS...
FEEL THE NAM AND ECMWF ARE TOO FAR NORTH, SLOW, AND DEEP W/THIS
FEATURE...THUS THEY ALSO CRANK OUT TOO MUCH QPF. NEVERTHELESS...
QPF COMBINED WITH MARGINAL TEMPERATURE PROFILES OVER THE NORTHWEST
COULD SUPPORT SOME LIGHT FREEZING RAIN MONDAY NIGHT. MID-LEVEL FLOW
THEN BECOMES INCREASINGLY MERIDIONAL...PUMPING ANOMALOUSLY WARM
AND MOIST AIR UP THE EAST COAST...SETTING THE STAGE FOR HEAVY RAIN
ON CHRISTMAS EVE DAY. THE TROUGH LOOKS TO BECOME NEGATIVELY TILTED
AS IT CROSSES THE REGION...LEADING TO A STRONG FRONTAL PASSAGE LATE
WEDNESDAY INTO EARLY THURSDAY...WITH SOME FLURRIES POSSIBLE ON THE
BACK-SIDE OF THE STORM SYSTEM.

DETAILS...

MONDAY...
MID-LEVEL RIDGE CRESTS OVER THE REGION EARLY IN THE DAY...W/SURFACE
HIGH ANCHORED ALONG THE EAST COAST IN A COLD-AIR DAMMING SIGNATURE.
PRECIPITATION WILL BE LARGELY DRIVEN BY INSENTROPIC ASCENT OVER THE
COLDER LOW-LEVEL AIRMASS AND WILL BEGIN LATE IN THE DAY AS MOISTURE
STREAMS IN ALOFT AND LOW-LEVELS GRADUALLY SATURATE. THERE MAY BE A
PERIOD OF LIGHT FREEZING RAIN OVER THE NORTHWEST AS A COLD AIR
IS REINFORCED W/NORTHERLY SURFACE WINDS AND PRECIP LEADS TO
EVAPORATIONAL COOLING.

TUESDAY...
ANY LIGHT FREEZING RAIN SHOULD END EARLY IN THE MORNING WITH STRONG
WARM AIR ADVECTION ALOFT. ALTHOUGH THE BEST FORCING REMAINS WELL TO
THE WEST...BROAD ISENTROPIC ASCENT AND INCREASING MOISTURE SHOULD
LEAD TO SCATTERED RAIN SHOWERS THRU THE DAY. QPF SHOULD BE GENERALLY
LIGHT.

WEDNESDAY...
A VIGOROUS TROUGH APPROACHES FROM THE WEST W/STILL SOME SPREAD NOTED
FROM THE MEAN IN BOTH THE ECENS AND GEFS 500 HPA HEIGHT FIELDS...
INDICATING SOME DISAGREEMENT WITH REGARD TO WHAT DEGREE IT GOES
NEGATIVELY TILTED. NEVERTHELESS...A VERY DYNAMIC SYSTEM WITH SEVERAL
INGREDIENTS COMING TOGETHER FOR UP TO 1-2 INCHES OF QPF...ESPECIALLY
OVER THE HIGHER TERRAIN. NOTING A STRONG MID-LEVEL VORT MAX AND THE
LEFT-FRONT QUADRANT OF A 160 KNOT UPPER-LEVEL JET TRAVERSING THE
APPALACHIANS. ALSO NOTING STRONG WARM AIR ADVECTION AND ANOMALOUSLY
HIGH /2-3 STANDARD DEVIATION/ PRECIPITABLE WATER VALUES STREAMING
UP THE EASTERN SEABOARD. THUS THERE IS PLENTY OF MOISTURE AND
ASCENT FOR HEAVY RAINFALL...W/THE MODELS KEYING IN ON WEDNESDAY
AFTERNOON AND WEDNESDAY NIGHT FOR THE BULK OF THE PRECIP...AND
THIS WILL NEED TO BE MONITORED FOR FLOODING POTENTIAL PARTICULARLY
DUE TO THE HOLIDAY TRAVEL CHRISTMAS EVE. LATER SHIFTS WILL ALSO
NEED TO FURTHER EVALUATE THE POTENTIAL FOR GUSTY SURFACE WINDS
AND CONVECTION.

THURSDAY AND FRIDAY...
LOW-PRESSURE MOVES NORTHWARD INTO QUEBEC AND HIGH-PRESSURE BEGINS TO
BUILD IN. TEMPERATURES WILL REMAIN ABOVE SEASONABLE LEVELS AND THERE
COULD BE SNOW SHOWERS IN THE BLUSTERY NORTHWEST FLOW ON THURSDAY...
PARTICULARLY NORTHWEST.

SATURDAY...ANOTHER COLD FRONT MAY APPROACH THE REGION...BUT IT/S TOO
EARLY TO SPECULATE...ESPECIALLY GIVEN THE UNCERTAINTY THAT THE STORM
SYSTEM MOVING THROUGH THE NORTHEAST CONUS MID-WEEK COULD ADD TO THE
FORECAST.

&&

.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

THERE HAS BEEN PLENTY OF LOW LEVEL MOISTURE TRAPPED BELOW THE
INVERSION AGAIN TODAY. CIGS WERE BETWEEN 025-035 ACROSS THE AREA
THIS AFTERNOON. THIS EVENING WE`RE SEEING MORE 030-035. STILL,
MOSTLY IN THE NORTH QUADRANT.

WE`LL KEEP THE LOW CLOUDS IN THE TERMINALS FROM KPHL NORTHWARD
THROUGH THE NIGHT. TO THE SOUTH, WE`VE SCATTERED THE LOW LEVEL
DECK OUT. A SHORT WAVE WILL BRING SOME ALTOCU TO JUST ABOUT
EVERYWHERE OVERNIGHT.

WINDS WILL REMAIN LIGHT OVERNIGHT. NO PRECIPITATION HAS BEEN
MENTIONED.

OUTLOOK...

SUNDAY NIGHT AND MONDAY MORNING...VFR.

MONDAY AFTERNOON...POTENTIAL FOR MVFR CIGS AS MARINE LAYER BECOMES
ESTABLISHED AND STRATUS ADVECTS INLAND.

MONDAY NIGHT THROUGH TUESDAY NIGHT...THE COMBINATION OF
STRENGTHENING ONSHORE FLOW AND IN-SITU CAD FROM LIGHT RAIN
OVERSPREADING THE TERMINALS COULD YIELD AN EXTENDED PERIOD OF
MVFR/IFR CONDITIONS (CIGS WOULD BE THE MORE LIKELY CONTRIBUTOR TO
IFR THAN VSBYS) MONDAY NIGHT INTO TUESDAY.

WEDNESDAY...WINDS VEER MORE OUT OF THE SOUTH AS A WARM FRONT SLOWLY
LIFTS NORTHWARD. RAIN IS EXPECTED TO BE THE MOST WIDESPREAD AND
HEAVIEST DURING THIS PART OF THE FORECAST PERIOD. PREDOMINATELY MVFR
AND IFR CONDITIONS. SOUTHERLY WINDS WILL BECOME BREEZY FOLLOWING
WARM FROPA.

WEDNESDAY NIGHT...COLD FRONT IS FORECAST TO MOVE THRU SOMETIME AT
NIGHT. LOW CLOUDS AND RAIN WILL END FROM WEST TO EAST IN WAKE OF
FROPA.

THURSDAY...WESTERLY WINDS COULD BECOME STRONG BEHIND THE FRONT
THURSDAY WITH BUFKIT FORECAST SOUNDINGS FROM THE 12Z GFS SHOWING THE
POTENTIAL FOR 30-40 KT GUSTS.

&&

.MARINE...
WEAK HIGH PRESSURE WILL REMAIN ACROSS THE WATERS TONIGHT AND SUNDAY.
WINDS AND SEAS WILL REMAIN BELOW SCA FLAG CRITERIA. WINDS WILL
MOSTLY BE NORTHERLY THROUGH THE PERIOD.

OUTLOOK...
SUNDAY NIGHT THROUGH MONDAY NIGHT...WINDS AND SEAS BELOW SCA
CRITERIA.

TUESDAY AND TUESDAY NIGHT...ONSHORE FLOW STRENGTHENS ON TUESDAY.
WINDS 15-20 KT FORECAST ON TUESDAY. SEAS ARE FORECAST TO BUILD TO
5-6 FEET TUESDAY AND TUESDAY NIGHT, WARRANTING THE NEED FOR A SCA.

WEDNESDAY AND WEDNESDAY NIGHT...SOUTHERLY WINDS STRENGTHEN AFTER
WARM FROPA. DESPITE WINDS OF 40-50 KT FORECAST 1000 FT ABOVE THE
SURFACE, THERMAL PROFILES NOT FAVORABLE FOR MIXING WITH THE SETUP OF
WARM AIR MOVING ATOP THE COOLER WATERS. EXPECTING MORE OF A HIGH END
SCA WITH 25-30 KT WINDS. WINDS FORECAST TO BECOME WESTERLY LATE
WEDNESDAY NIGHT BEHIND A COLD FRONT BUT THE CORE OF THE COLD AIR
WILL STILL REMAIN UPSTREAM OF THE WATERS. SEAS FORECAST TO INCREASE
TO 6-8 FEET.

THURSDAY...GUSTY WESTERLY WINDS EXPECTED. GALES CERTAINLY A
POSSIBILITY.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANCK
NEAR TERM...O`HARA
SHORT TERM...O`HARA
LONG TERM...FRANCK
AVIATION...FRANCK/KLEIN/O`HARA
MARINE...KLEIN/O`HARA







000
FXUS61 KPHI 210216
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
916 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE WILL SLOWLY BUILD SOUTHWESTWARD INTO THE REGION
FROM ATLANTIC CANADA THROUGH MONDAY. LOW PRESSURE WILL ORGANIZE
OFF THE CAROLINAS MONDAY NIGHT AND MOVE NORTHEASTWARD OFFSHORE ON
TUESDAY. MEANWHILE...ANOTHER AREA OF LOW PRESSURE WILL DEVELOP
OVER THE OHIO VALLEY AND MOVE NORTHWARD INTO QUEBEC...LEADING TO A
STRONG COLD FRONTAL PASSAGE ON THURSDAY NIGHT. HIGH PRESSURE WILL
BUILD IN ON FRIDAY AND A WEAKER COLD FRONT MAY APPROACH THE REGION
NEXT WEEKEND.

&&

.NEAR TERM /THROUGH SUNDAY/...
WEAK SURFACE HIGH PRESSURE WILL REMAIN ACROSS THE AREA TONIGHT.
PLENTY OF MOISTURE REMAINS TRAPPED BELOW A LOW LEVEL INVERSION,
ESPECIALLY PHILLY NORTH. THE LOW CLOUDS HAVE BROKEN UP SOUTH OF
PHILLY, BUT SKIES WILL FILL UP AGAIN AS A MID-LEVEL DECK ADVECTS
IN OVERNIGHT. THESE CLOUDS ARE ASSOCIATED WITH A MID-LEVEL SHORT
WAVE.

THE HIGH RESOLUTION MODELS KEEP THE CWA PRECIP-FREE(MEASURABLE)
THROUGH THE OVERNIGHT AS DOES THE LOWER RES MODELS. WE`LL KEEP THE
GRIDS AS IS, BUT CAN`T RULE OUT A FLURRY OR TWO UP ACROSS THE
NORTHERN THIRD OF THE CWA.

ANOTHER SEASONABLY COLD NIGHT IS EXPECTED WITH LOWS IN THE LOW 20S
NORTH AND MID OR UPPER 20S SOUTH. WINDS WILL BE LIGHT FROM THE
NORTH.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH 6 PM SUNDAY/...
AFTER A WEAK SHORTWAVE CROSSES THE AREA SUN MORNING...UPPER RIDGING
WILL TAKE PLACE. THIS WILL HOPEFULLY ALLOW MORE SUNSHINE ACROSS THE
AREA. WE HAVE WRITTEN A PARTLY TO MOSTLY SUNNY FCST FOR NOW. WE HELD
ONTO SOME EXTRA CLOUD COVER ACROSS THE SRN POCONOS HOWEVER. HIGH
TEMPERATURES SUNDAY WILL RISE INTO THE LOW 40S ACROSS SRN NJ AND THE
DELMARVA...WHILE READINGS HOLD IN THE MID/UPPER 30S ACROSS THE
NORTH/WEST AREAS. WINDS WILL REMAIN LIGHT...MOSTLY FROM THE NORTH.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
HIGHLIGHTS...

* FREEZING RAIN POSSIBLE MONDAY NIGHT OVER THE NORTHWEST.
* INCREASING POTENTIAL FOR HEAVY RAIN CHRISTMAS EVE WITH
  TEMPERATURES WELL ABOVE NORMAL.
* BRISK WESTERLY WIND CHRISTMAS DAY W/FLURRIES POSSIBLE.

OVERVIEW...

VIGOROUS MID-LEVEL DISTURBANCE AND ACCOMPANYING 160 KNOT UPPER-LEVEL
JET MAX COMING ASHORE OVER THE PACIFIC NORTHWEST LATE THIS WEEKEND
WILL LEAD TO A DEEP TROUGH OVER THE MISSISSIPPI VALLEY BY MID-WEEK.
INITIAL PIECE OF ENERGY AHEAD OF THIS TROUGH IS EJECTED NORTHEAST
AND WILL LEAD TO THE DEVELOPMENT OF AN AREA OF LOW-PRESSURE OFF THE
CAROLINAS ON MONDAY. THIS WEAK FEATURE SHOULD TRACK OFFSHORE WELL
SOUTHEAST OF THE REGION ON TUESDAY PER TODAYS 12Z UKMET AND GFS...
FEEL THE NAM AND ECMWF ARE TOO FAR NORTH, SLOW, AND DEEP W/THIS
FEATURE...THUS THEY ALSO CRANK OUT TOO MUCH QPF. NEVERTHELESS...
QPF COMBINED WITH MARGINAL TEMPERATURE PROFILES OVER THE NORTHWEST
COULD SUPPORT SOME LIGHT FREEZING RAIN MONDAY NIGHT. MID-LEVEL FLOW
THEN BECOMES INCREASINGLY MERIDIONAL...PUMPING ANOMALOUSLY WARM
AND MOIST AIR UP THE EAST COAST...SETTING THE STAGE FOR HEAVY RAIN
ON CHRISTMAS EVE DAY. THE TROUGH LOOKS TO BECOME NEGATIVELY TILTED
AS IT CROSSES THE REGION...LEADING TO A STRONG FRONTAL PASSAGE LATE
WEDNESDAY INTO EARLY THURSDAY...WITH SOME FLURRIES POSSIBLE ON THE
BACK-SIDE OF THE STORM SYSTEM.

DETAILS...

MONDAY...
MID-LEVEL RIDGE CRESTS OVER THE REGION EARLY IN THE DAY...W/SURFACE
HIGH ANCHORED ALONG THE EAST COAST IN A COLD-AIR DAMMING SIGNATURE.
PRECIPITATION WILL BE LARGELY DRIVEN BY INSENTROPIC ASCENT OVER THE
COLDER LOW-LEVEL AIRMASS AND WILL BEGIN LATE IN THE DAY AS MOISTURE
STREAMS IN ALOFT AND LOW-LEVELS GRADUALLY SATURATE. THERE MAY BE A
PERIOD OF LIGHT FREEZING RAIN OVER THE NORTHWEST AS A COLD AIR
IS REINFORCED W/NORTHERLY SURFACE WINDS AND PRECIP LEADS TO
EVAPORATIONAL COOLING.

TUESDAY...
ANY LIGHT FREEZING RAIN SHOULD END EARLY IN THE MORNING WITH STRONG
WARM AIR ADVECTION ALOFT. ALTHOUGH THE BEST FORCING REMAINS WELL TO
THE WEST...BROAD ISENTROPIC ASCENT AND INCREASING MOISTURE SHOULD
LEAD TO SCATTERED RAIN SHOWERS THRU THE DAY. QPF SHOULD BE GENERALLY
LIGHT.

WEDNESDAY...
A VIGOROUS TROUGH APPROACHES FROM THE WEST W/STILL SOME SPREAD NOTED
FROM THE MEAN IN BOTH THE ECENS AND GEFS 500 HPA HEIGHT FIELDS...
INDICATING SOME DISAGREEMENT WITH REGARD TO WHAT DEGREE IT GOES
NEGATIVELY TILTED. NEVERTHELESS...A VERY DYNAMIC SYSTEM WITH SEVERAL
INGREDIENTS COMING TOGETHER FOR UP TO 1-2 INCHES OF QPF...ESPECIALLY
OVER THE HIGHER TERRAIN. NOTING A STRONG MID-LEVEL VORT MAX AND THE
LEFT-FRONT QUADRANT OF A 160 KNOT UPPER-LEVEL JET TRAVERSING THE
APPALACHIANS. ALSO NOTING STRONG WARM AIR ADVECTION AND ANOMALOUSLY
HIGH /2-3 STANDARD DEVIATION/ PRECIPITABLE WATER VALUES STREAMING
UP THE EASTERN SEABOARD. THUS THERE IS PLENTY OF MOISTURE AND
ASCENT FOR HEAVY RAINFALL...W/THE MODELS KEYING IN ON WEDNESDAY
AFTERNOON AND WEDNESDAY NIGHT FOR THE BULK OF THE PRECIP...AND
THIS WILL NEED TO BE MONITORED FOR FLOODING POTENTIAL PARTICULARLY
DUE TO THE HOLIDAY TRAVEL CHRISTMAS EVE. LATER SHIFTS WILL ALSO
NEED TO FURTHER EVALUATE THE POTENTIAL FOR GUSTY SURFACE WINDS
AND CONVECTION.

THURSDAY AND FRIDAY...
LOW-PRESSURE MOVES NORTHWARD INTO QUEBEC AND HIGH-PRESSURE BEGINS TO
BUILD IN. TEMPERATURES WILL REMAIN ABOVE SEASONABLE LEVELS AND THERE
COULD BE SNOW SHOWERS IN THE BLUSTERY NORTHWEST FLOW ON THURSDAY...
PARTICULARLY NORTHWEST.

SATURDAY...ANOTHER COLD FRONT MAY APPROACH THE REGION...BUT IT/S TOO
EARLY TO SPECULATE...ESPECIALLY GIVEN THE UNCERTAINTY THAT THE STORM
SYSTEM MOVING THROUGH THE NORTHEAST CONUS MID-WEEK COULD ADD TO THE
FORECAST.

&&

.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

THERE HAS BEEN PLENTY OF LOW LEVEL MOISTURE TRAPPED BELOW THE
INVERSION AGAIN TODAY. CIGS WERE BETWEEN 025-035 ACROSS THE AREA
THIS AFTERNOON. THIS EVENING WE`RE SEEING MORE 030-035. STILL,
MOSTLY IN THE NORTH QUADRANT.

WE`LL KEEP THE LOW CLOUDS IN THE TERMINALS FROM KPHL NORTHWARD
THROUGH THE NIGHT. TO THE SOUTH, WE`VE SCATTERED THE LOW LEVEL
DECK OUT. A SHORT WAVE WILL BRING SOME ALTOCU TO JUST ABOUT
EVERYWHERE OVERNIGHT.

WINDS WILL REMAIN LIGHT OVERNIGHT. NO PRECIPITATION HAS BEEN
MENTIONED.

OUTLOOK...

SUNDAY NIGHT AND MONDAY MORNING...VFR.

MONDAY AFTERNOON...POTENTIAL FOR MVFR CIGS AS MARINE LAYER BECOMES
ESTABLISHED AND STRATUS ADVECTS INLAND.

MONDAY NIGHT THROUGH TUESDAY NIGHT...THE COMBINATION OF
STRENGTHENING ONSHORE FLOW AND IN-SITU CAD FROM LIGHT RAIN
OVERSPREADING THE TERMINALS COULD YIELD AN EXTENDED PERIOD OF
MVFR/IFR CONDITIONS (CIGS WOULD BE THE MORE LIKELY CONTRIBUTOR TO
IFR THAN VSBYS) MONDAY NIGHT INTO TUESDAY.

WEDNESDAY...WINDS VEER MORE OUT OF THE SOUTH AS A WARM FRONT SLOWLY
LIFTS NORTHWARD. RAIN IS EXPECTED TO BE THE MOST WIDESPREAD AND
HEAVIEST DURING THIS PART OF THE FORECAST PERIOD. PREDOMINATELY MVFR
AND IFR CONDITIONS. SOUTHERLY WINDS WILL BECOME BREEZY FOLLOWING
WARM FROPA.

WEDNESDAY NIGHT...COLD FRONT IS FORECAST TO MOVE THRU SOMETIME AT
NIGHT. LOW CLOUDS AND RAIN WILL END FROM WEST TO EAST IN WAKE OF
FROPA.

THURSDAY...WESTERLY WINDS COULD BECOME STRONG BEHIND THE FRONT
THURSDAY WITH BUFKIT FORECAST SOUNDINGS FROM THE 12Z GFS SHOWING THE
POTENTIAL FOR 30-40 KT GUSTS.

&&

.MARINE...
WEAK HIGH PRESSURE WILL REMAIN ACROSS THE WATERS TONIGHT AND SUNDAY.
WINDS AND SEAS WILL REMAIN BELOW SCA FLAG CRITERIA. WINDS WILL
MOSTLY BE NORTHERLY THROUGH THE PERIOD.

OUTLOOK...
SUNDAY NIGHT THROUGH MONDAY NIGHT...WINDS AND SEAS BELOW SCA
CRITERIA.

TUESDAY AND TUESDAY NIGHT...ONSHORE FLOW STRENGTHENS ON TUESDAY.
WINDS 15-20 KT FORECAST ON TUESDAY. SEAS ARE FORECAST TO BUILD TO
5-6 FEET TUESDAY AND TUESDAY NIGHT, WARRANTING THE NEED FOR A SCA.

WEDNESDAY AND WEDNESDAY NIGHT...SOUTHERLY WINDS STRENGTHEN AFTER
WARM FROPA. DESPITE WINDS OF 40-50 KT FORECAST 1000 FT ABOVE THE
SURFACE, THERMAL PROFILES NOT FAVORABLE FOR MIXING WITH THE SETUP OF
WARM AIR MOVING ATOP THE COOLER WATERS. EXPECTING MORE OF A HIGH END
SCA WITH 25-30 KT WINDS. WINDS FORECAST TO BECOME WESTERLY LATE
WEDNESDAY NIGHT BEHIND A COLD FRONT BUT THE CORE OF THE COLD AIR
WILL STILL REMAIN UPSTREAM OF THE WATERS. SEAS FORECAST TO INCREASE
TO 6-8 FEET.

THURSDAY...GUSTY WESTERLY WINDS EXPECTED. GALES CERTAINLY A
POSSIBILITY.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANCK
NEAR TERM...O`HARA
SHORT TERM...O`HARA
LONG TERM...FRANCK
AVIATION...FRANCK/KLEIN/O`HARA
MARINE...KLEIN/O`HARA







000
FXUS61 KCTP 210019
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
719 PM EST SAT DEC 20 2014

.SYNOPSIS...
AN AMPLIFYING UPPER RIDGE WILL MOVE INTO THE REGION ON
SUNDAY. TEMPERATURES WILL THEN BECOME JUST SLIGHTLY MILDER BUT
UNSETTLED CONDITIONS WILL BEGIN ON MONDAY NIGHT AND PREVAIL
THROUGH MID WEEK. A VIGOROUS STORM SYSTEM WILL SWEEP ACROSS THE
COMMONWEALTH ON CHRISTMAS EVE BRINGING WIDESPREAD SHOWERS AND A
CHANCE FOR THUNDERSTORMS. WINDY AND COLDER CONDITIONS WILL FOLLOW
WITH SCATTERED SNOW SHOWERS ACROSS THE WEST AND NORTH FOR
CHRISTMAS DAY. MILDER CONDITIONS WILL RETURN LATE THIS WEEK.

&&

.NEAR TERM /UNTIL 7 AM SUNDAY MORNING/...
CLOUDS CONGESTING OVER THE AREA BUT SOME AREAS STILL FREE OF THE
LOWEST DECK. A VIGOROUS SHORT WAVE ROLLING OVERHEAD EARLY TONIGHT
MAY CREATE ENOUGH LIFT AND COULD SEED THE LOWER CLOUDS WITH ICE
CRYSTALS FROM ABOVE. THUS...SOME FLURRIES ARE EXPECTED OVER THE
LAURELS AND ALONG THE NRN TIER. WILL LEAVE ACCUMS OUT OF THE FCST
FOR NOW. MINS PROBABLY A HOMOGENEOUS 20-25F ACROSS THE BOARD.

&&

.SHORT TERM /7 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
DEEP LAYER DRYING BEHIND A DEPARTING 5H WAVE AND UPPER LEVEL
RIDGING HAS THE POTENTIAL TO BRING SUNSHINE TO MOST IF NOT ALL OF
CENTRAL PA ON MONDAY. THE STUBBORN STRATUS THAT HAS PLAGUED US FOR
MORE THAN A WEEK WILL HAVE A CHANCE TO MIX OUT...BUT TRANSITORY
SFC HIGH PRESSURE MAY STILL MAKE THIS A SLOW PROCESS OVER THE
NORTH.

PRIOR TO THAT...SOME AREAS COULD PERHAPS SEE A FLURRY IN THE PRE
DAWN HOURS SUNDAY BEFORE THE WAVE QUICKLY EXITS EASTWARD. WENT
CLOSE TO CONSALL GUIDANCE AGAIN WITH MAXES REACHING THE MID TO
UPPER 30S NORTH TO THE LOWER 40S SOUTH.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
THE MOST SIGNIFICANT FORECAST ISSUE IN THE LONG TERM IS THE
EVOLUTION OF THE MASSIVE CYCLONE TO OUR WEST 23-25 DECEMBER.
STRONG SOUTHERLY FLOW AHEAD OF THIS SYSTEM WILL BRING WARM AIR
INTO THE REGION LATE MONDAY INTO TUESDAY. BY TUESDAY AND WEDNESDAY
MANY LOW- LEVEL TEMPERATURE AND MOISTURE FIELDS WILL BE WELL ABOVE
THEIR SEASONAL VALUES. THIS IMPLIES VERY WARM WEATHER TUESDAY AND
WEDNESDAY...WHEN THE SHALLOW COLD AIR SCOURS OUT EAST OF THE
MOUNTAINS.

A COLD FRONT WITH STRONG WINDS WILL PRODUCE COLDER
CONDITIONS...LIKELY LATE CHRISTMAS EVE INTO CHRISTMAS DAY. THERE
WILL BE STRONG WESTERLY WINDS AND STRONG WIND GUSTS. SNOW SHOWERS
ARE LIKELY BEHIND THE SYSTEM IN WESTERN AREAS.

THE CHANGEABLE DETAILS...MONDAY THE ENSEMBLE FORECAST SHOWS A
WAVE PASSING TO OUR SOUTH WHICH COULD PRODUCE LIGHT SNOW OR A
MIX...MAINLY IN SOUTHEASTERN AREAS. THE IMPLIED LOW-LEVEL BOUNDARY
IS THE RETREATING COLD AIR TO OUR NORTHEAST AS THE STRONG CYCLONE
TO OUR WEST BEGINS TO TAKE SHAPE. IMPLIED LOW-LEVEL AGEOSTROPHIC
NORTHERLY FLOW HOLDING LOW-LEVEL COLD AIR IN MONDAY INTO TUESDAY.

TUESDAY THE COLD AIR SHOULD CONTINUE TO ERODE. HAD TO KEEP SOME
FREEZE RAIN/DRIZZLE IN NORTHEASTERN AREAS OVERNIGHT MONDAY INTO
TUESDAY BASED ON IMPLIED AGEOSTROPHIC FLOW AND ENSEMBLE
PRECIPITATION TYPES. BUT DURING THE DAY TUESDAY THE WARM AIR
SHOULD WIN OUT. THOUGH ALL SYSTEMS SHOW SOME HINTS OF COLD AIR
DAMMING....DAYTIME HIGHS EAST/NORTHEAST AREAS WILL BE WELL BELOW
WHAT ONE MIGHT EXPECT WITH 6-10C 850 MB TEMPS.

ANY PRECIPITATION TUESDAY AND WEDNESDAY SHOULD BE RAIN MUCH AFTER
NOON TUESDAY IN THE NORTHEAST. PRECIPITATION ON TUESDAY SHOULD BE
LIGHT...ENSEMBLES SHOW PROBABILITIES IN THE 20-30 RANGE AND LIGHT
AMOUNTS. THE PATTERN...SHARP NORTH-SOUTH FRONT TO OUR
WEST...IMPLIES SOME ISOLATED SHOWERS BUT THE MAIN RAIN EVENT
SHOULD WITHIN 3-6 HOURS OF THE FRONT.

TUESDAY THE STRONG CYCLONE...WITH SOME OF THE LOWEST SURFACE
PRESSURES IN THE EASTERN US ON 24 DECEMBER IN THE PAST 30 YEARS
WILL MOVE INTO THE GREAT LAKES. PRESSURE ANOMALIES ARE -3 TO -4
SIGMA BELOW NORMAL WITH A RETURN PERIOD ON THE ORDER OF 30 YEARS
IN SOME FORECAST SYSTEMS.

THE FRONT ASSOCIATED WITH THE CYCLONE PUSHES INTO OUR REGION
WEDNESDAY...AT THIS TIME THE 850 MB SOUTHERLY WINDS ARE FORECAST
TO BE ABOUT +3 SIGMA ABOVE NORMAL. THE STRONG SOUTHERLY FLOW...THE
HIGH PRECIPITABLE WATER...THE STRONG FRONT ALL IMPLY A FRONTAL
RAIN EVENT AND PERHAPS SOME RARE LATE DECEMBER (ELEVATED)
CONVECTION. IF THIS WERE AUTUMN OR SPRING WE MIGHT BE THINKING
QLCS. BUT SURFACE CAPE IS VIRTUALLY NON-EXISTENT BUT SHOWERY RAIN
AND PERHAPS ISOLATED THUNDER POSSIBLE.

DO NOT LIKE HAVING POPS ABOVE 60 TO 66 PERCENT AT DAY 5 IN 12 HOUR
PERIODS. TIMING WILL CLEARLY CHANGE BUT HAVE HIGH POPS FOR
CONSISTENCY WITH OTHER OFFICES.

CHRISTMAS EVE AND EARLY CHRISTMAS IS THE AREA OF HIGH UNCERTAINTY
AS TO WHEN THE COLD AIR COMES IN. THIS WILL DICTATE WHEN THE RAIN
COMES AND WHEN THE GUSTY WINDS SET IN. GRADIENTS ARE WHERE
FORECASTS ARE THEIR POOREST. BUT BY CHRISTMAS MORNING MOST IF NOT
ALL OF THE REGION SHOULD BE BELOW 0C AT 850 AND THE STRONG
WESTERLY WINDS SHOULD BE MIXING DOWN BEHIND THE FRONTAL BOUNDARY.
WINDY OVERNIGHT CHRISTMAS EVE INTO CHRISTMAS DAY. ANY RESIDUAL
PRECIPITATION SHOULD BE SNOW/SNOW SHOWERS AND FLURRIES.

TEMPERATURES SHOULD REBOUND FRIDAY AHEAD OF ANOTHER NORTHERN STREAM
WAVE MOVING INTO THE MID-WEST. THIS SHOULD RAISE OUR HEIGHTS AND
TEMPERATURES FRIDAY INTO EARLY SATURDAY. IT APPEARS A SERIES OF
WAVES MAY EVENTUALLY CARVE OUT A TROUGH OVER THE EAST-CENTRAL US. IF
SO...WE COULD END DECEMBER A BIT ON THE CHILLY SIDE.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
A WEAK AND SHALLOW STRATOCU DECK REMAINS TRAPPED BENEATH
SUBSIDENCE. THE CIG RESTRICTIONS WILL SPREAD AND INCREASE DUE TO
THE STRENGTHENING OF THE INVERSION OVERNIGHT. EXPECT THE
EXPANDING STRATOCU DECK LIKELY TO RETURN AGAIN TONIGHT...THOUGH
LOW CLOUDS SHOULD NOT BE QUITE AS EXPANSIVE AS PREVIOUS NIGHTS. A
SHORTWAVE WILL TRACK ACROSS THE REGION BRINGING A THICKENING MID-
LVL DECK AS WELL. SURFACE WINDS WILL CONTINUE TO BE LIGHT...WITH
SW FLOW ALOFT BEGINNING TO INCREASE AS A LARGE LOW PRESSURE SYSTEM
BEGINS TO DEEPEN OVER THE CENTRAL U.S. EXPECT MVFR CIGS AT THE
CENTRAL SITES AOO AND UNV...WITH IFR POSSIBLE AT BFD AND
JST...WITH MAINLY VFR THROUGH THE EASTERN TAF SITES.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

THU...WINDY AND COLDER WITH SCT MVFR CIGS AND -SHSN.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...FITZGERALD
LONG TERM...GRUMM
AVIATION...DEVOIR/CERU



000
FXUS61 KCTP 210019
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
719 PM EST SAT DEC 20 2014

.SYNOPSIS...
AN AMPLIFYING UPPER RIDGE WILL MOVE INTO THE REGION ON
SUNDAY. TEMPERATURES WILL THEN BECOME JUST SLIGHTLY MILDER BUT
UNSETTLED CONDITIONS WILL BEGIN ON MONDAY NIGHT AND PREVAIL
THROUGH MID WEEK. A VIGOROUS STORM SYSTEM WILL SWEEP ACROSS THE
COMMONWEALTH ON CHRISTMAS EVE BRINGING WIDESPREAD SHOWERS AND A
CHANCE FOR THUNDERSTORMS. WINDY AND COLDER CONDITIONS WILL FOLLOW
WITH SCATTERED SNOW SHOWERS ACROSS THE WEST AND NORTH FOR
CHRISTMAS DAY. MILDER CONDITIONS WILL RETURN LATE THIS WEEK.

&&

.NEAR TERM /UNTIL 7 AM SUNDAY MORNING/...
CLOUDS CONGESTING OVER THE AREA BUT SOME AREAS STILL FREE OF THE
LOWEST DECK. A VIGOROUS SHORT WAVE ROLLING OVERHEAD EARLY TONIGHT
MAY CREATE ENOUGH LIFT AND COULD SEED THE LOWER CLOUDS WITH ICE
CRYSTALS FROM ABOVE. THUS...SOME FLURRIES ARE EXPECTED OVER THE
LAURELS AND ALONG THE NRN TIER. WILL LEAVE ACCUMS OUT OF THE FCST
FOR NOW. MINS PROBABLY A HOMOGENEOUS 20-25F ACROSS THE BOARD.

&&

.SHORT TERM /7 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
DEEP LAYER DRYING BEHIND A DEPARTING 5H WAVE AND UPPER LEVEL
RIDGING HAS THE POTENTIAL TO BRING SUNSHINE TO MOST IF NOT ALL OF
CENTRAL PA ON MONDAY. THE STUBBORN STRATUS THAT HAS PLAGUED US FOR
MORE THAN A WEEK WILL HAVE A CHANCE TO MIX OUT...BUT TRANSITORY
SFC HIGH PRESSURE MAY STILL MAKE THIS A SLOW PROCESS OVER THE
NORTH.

PRIOR TO THAT...SOME AREAS COULD PERHAPS SEE A FLURRY IN THE PRE
DAWN HOURS SUNDAY BEFORE THE WAVE QUICKLY EXITS EASTWARD. WENT
CLOSE TO CONSALL GUIDANCE AGAIN WITH MAXES REACHING THE MID TO
UPPER 30S NORTH TO THE LOWER 40S SOUTH.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
THE MOST SIGNIFICANT FORECAST ISSUE IN THE LONG TERM IS THE
EVOLUTION OF THE MASSIVE CYCLONE TO OUR WEST 23-25 DECEMBER.
STRONG SOUTHERLY FLOW AHEAD OF THIS SYSTEM WILL BRING WARM AIR
INTO THE REGION LATE MONDAY INTO TUESDAY. BY TUESDAY AND WEDNESDAY
MANY LOW- LEVEL TEMPERATURE AND MOISTURE FIELDS WILL BE WELL ABOVE
THEIR SEASONAL VALUES. THIS IMPLIES VERY WARM WEATHER TUESDAY AND
WEDNESDAY...WHEN THE SHALLOW COLD AIR SCOURS OUT EAST OF THE
MOUNTAINS.

A COLD FRONT WITH STRONG WINDS WILL PRODUCE COLDER
CONDITIONS...LIKELY LATE CHRISTMAS EVE INTO CHRISTMAS DAY. THERE
WILL BE STRONG WESTERLY WINDS AND STRONG WIND GUSTS. SNOW SHOWERS
ARE LIKELY BEHIND THE SYSTEM IN WESTERN AREAS.

THE CHANGEABLE DETAILS...MONDAY THE ENSEMBLE FORECAST SHOWS A
WAVE PASSING TO OUR SOUTH WHICH COULD PRODUCE LIGHT SNOW OR A
MIX...MAINLY IN SOUTHEASTERN AREAS. THE IMPLIED LOW-LEVEL BOUNDARY
IS THE RETREATING COLD AIR TO OUR NORTHEAST AS THE STRONG CYCLONE
TO OUR WEST BEGINS TO TAKE SHAPE. IMPLIED LOW-LEVEL AGEOSTROPHIC
NORTHERLY FLOW HOLDING LOW-LEVEL COLD AIR IN MONDAY INTO TUESDAY.

TUESDAY THE COLD AIR SHOULD CONTINUE TO ERODE. HAD TO KEEP SOME
FREEZE RAIN/DRIZZLE IN NORTHEASTERN AREAS OVERNIGHT MONDAY INTO
TUESDAY BASED ON IMPLIED AGEOSTROPHIC FLOW AND ENSEMBLE
PRECIPITATION TYPES. BUT DURING THE DAY TUESDAY THE WARM AIR
SHOULD WIN OUT. THOUGH ALL SYSTEMS SHOW SOME HINTS OF COLD AIR
DAMMING....DAYTIME HIGHS EAST/NORTHEAST AREAS WILL BE WELL BELOW
WHAT ONE MIGHT EXPECT WITH 6-10C 850 MB TEMPS.

ANY PRECIPITATION TUESDAY AND WEDNESDAY SHOULD BE RAIN MUCH AFTER
NOON TUESDAY IN THE NORTHEAST. PRECIPITATION ON TUESDAY SHOULD BE
LIGHT...ENSEMBLES SHOW PROBABILITIES IN THE 20-30 RANGE AND LIGHT
AMOUNTS. THE PATTERN...SHARP NORTH-SOUTH FRONT TO OUR
WEST...IMPLIES SOME ISOLATED SHOWERS BUT THE MAIN RAIN EVENT
SHOULD WITHIN 3-6 HOURS OF THE FRONT.

TUESDAY THE STRONG CYCLONE...WITH SOME OF THE LOWEST SURFACE
PRESSURES IN THE EASTERN US ON 24 DECEMBER IN THE PAST 30 YEARS
WILL MOVE INTO THE GREAT LAKES. PRESSURE ANOMALIES ARE -3 TO -4
SIGMA BELOW NORMAL WITH A RETURN PERIOD ON THE ORDER OF 30 YEARS
IN SOME FORECAST SYSTEMS.

THE FRONT ASSOCIATED WITH THE CYCLONE PUSHES INTO OUR REGION
WEDNESDAY...AT THIS TIME THE 850 MB SOUTHERLY WINDS ARE FORECAST
TO BE ABOUT +3 SIGMA ABOVE NORMAL. THE STRONG SOUTHERLY FLOW...THE
HIGH PRECIPITABLE WATER...THE STRONG FRONT ALL IMPLY A FRONTAL
RAIN EVENT AND PERHAPS SOME RARE LATE DECEMBER (ELEVATED)
CONVECTION. IF THIS WERE AUTUMN OR SPRING WE MIGHT BE THINKING
QLCS. BUT SURFACE CAPE IS VIRTUALLY NON-EXISTENT BUT SHOWERY RAIN
AND PERHAPS ISOLATED THUNDER POSSIBLE.

DO NOT LIKE HAVING POPS ABOVE 60 TO 66 PERCENT AT DAY 5 IN 12 HOUR
PERIODS. TIMING WILL CLEARLY CHANGE BUT HAVE HIGH POPS FOR
CONSISTENCY WITH OTHER OFFICES.

CHRISTMAS EVE AND EARLY CHRISTMAS IS THE AREA OF HIGH UNCERTAINTY
AS TO WHEN THE COLD AIR COMES IN. THIS WILL DICTATE WHEN THE RAIN
COMES AND WHEN THE GUSTY WINDS SET IN. GRADIENTS ARE WHERE
FORECASTS ARE THEIR POOREST. BUT BY CHRISTMAS MORNING MOST IF NOT
ALL OF THE REGION SHOULD BE BELOW 0C AT 850 AND THE STRONG
WESTERLY WINDS SHOULD BE MIXING DOWN BEHIND THE FRONTAL BOUNDARY.
WINDY OVERNIGHT CHRISTMAS EVE INTO CHRISTMAS DAY. ANY RESIDUAL
PRECIPITATION SHOULD BE SNOW/SNOW SHOWERS AND FLURRIES.

TEMPERATURES SHOULD REBOUND FRIDAY AHEAD OF ANOTHER NORTHERN STREAM
WAVE MOVING INTO THE MID-WEST. THIS SHOULD RAISE OUR HEIGHTS AND
TEMPERATURES FRIDAY INTO EARLY SATURDAY. IT APPEARS A SERIES OF
WAVES MAY EVENTUALLY CARVE OUT A TROUGH OVER THE EAST-CENTRAL US. IF
SO...WE COULD END DECEMBER A BIT ON THE CHILLY SIDE.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
A WEAK AND SHALLOW STRATOCU DECK REMAINS TRAPPED BENEATH
SUBSIDENCE. THE CIG RESTRICTIONS WILL SPREAD AND INCREASE DUE TO
THE STRENGTHENING OF THE INVERSION OVERNIGHT. EXPECT THE
EXPANDING STRATOCU DECK LIKELY TO RETURN AGAIN TONIGHT...THOUGH
LOW CLOUDS SHOULD NOT BE QUITE AS EXPANSIVE AS PREVIOUS NIGHTS. A
SHORTWAVE WILL TRACK ACROSS THE REGION BRINGING A THICKENING MID-
LVL DECK AS WELL. SURFACE WINDS WILL CONTINUE TO BE LIGHT...WITH
SW FLOW ALOFT BEGINNING TO INCREASE AS A LARGE LOW PRESSURE SYSTEM
BEGINS TO DEEPEN OVER THE CENTRAL U.S. EXPECT MVFR CIGS AT THE
CENTRAL SITES AOO AND UNV...WITH IFR POSSIBLE AT BFD AND
JST...WITH MAINLY VFR THROUGH THE EASTERN TAF SITES.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

THU...WINDY AND COLDER WITH SCT MVFR CIGS AND -SHSN.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...FITZGERALD
LONG TERM...GRUMM
AVIATION...DEVOIR/CERU



000
FXUS61 KCTP 210019
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
719 PM EST SAT DEC 20 2014

.SYNOPSIS...
AN AMPLIFYING UPPER RIDGE WILL MOVE INTO THE REGION ON
SUNDAY. TEMPERATURES WILL THEN BECOME JUST SLIGHTLY MILDER BUT
UNSETTLED CONDITIONS WILL BEGIN ON MONDAY NIGHT AND PREVAIL
THROUGH MID WEEK. A VIGOROUS STORM SYSTEM WILL SWEEP ACROSS THE
COMMONWEALTH ON CHRISTMAS EVE BRINGING WIDESPREAD SHOWERS AND A
CHANCE FOR THUNDERSTORMS. WINDY AND COLDER CONDITIONS WILL FOLLOW
WITH SCATTERED SNOW SHOWERS ACROSS THE WEST AND NORTH FOR
CHRISTMAS DAY. MILDER CONDITIONS WILL RETURN LATE THIS WEEK.

&&

.NEAR TERM /UNTIL 7 AM SUNDAY MORNING/...
CLOUDS CONGESTING OVER THE AREA BUT SOME AREAS STILL FREE OF THE
LOWEST DECK. A VIGOROUS SHORT WAVE ROLLING OVERHEAD EARLY TONIGHT
MAY CREATE ENOUGH LIFT AND COULD SEED THE LOWER CLOUDS WITH ICE
CRYSTALS FROM ABOVE. THUS...SOME FLURRIES ARE EXPECTED OVER THE
LAURELS AND ALONG THE NRN TIER. WILL LEAVE ACCUMS OUT OF THE FCST
FOR NOW. MINS PROBABLY A HOMOGENEOUS 20-25F ACROSS THE BOARD.

&&

.SHORT TERM /7 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
DEEP LAYER DRYING BEHIND A DEPARTING 5H WAVE AND UPPER LEVEL
RIDGING HAS THE POTENTIAL TO BRING SUNSHINE TO MOST IF NOT ALL OF
CENTRAL PA ON MONDAY. THE STUBBORN STRATUS THAT HAS PLAGUED US FOR
MORE THAN A WEEK WILL HAVE A CHANCE TO MIX OUT...BUT TRANSITORY
SFC HIGH PRESSURE MAY STILL MAKE THIS A SLOW PROCESS OVER THE
NORTH.

PRIOR TO THAT...SOME AREAS COULD PERHAPS SEE A FLURRY IN THE PRE
DAWN HOURS SUNDAY BEFORE THE WAVE QUICKLY EXITS EASTWARD. WENT
CLOSE TO CONSALL GUIDANCE AGAIN WITH MAXES REACHING THE MID TO
UPPER 30S NORTH TO THE LOWER 40S SOUTH.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
THE MOST SIGNIFICANT FORECAST ISSUE IN THE LONG TERM IS THE
EVOLUTION OF THE MASSIVE CYCLONE TO OUR WEST 23-25 DECEMBER.
STRONG SOUTHERLY FLOW AHEAD OF THIS SYSTEM WILL BRING WARM AIR
INTO THE REGION LATE MONDAY INTO TUESDAY. BY TUESDAY AND WEDNESDAY
MANY LOW- LEVEL TEMPERATURE AND MOISTURE FIELDS WILL BE WELL ABOVE
THEIR SEASONAL VALUES. THIS IMPLIES VERY WARM WEATHER TUESDAY AND
WEDNESDAY...WHEN THE SHALLOW COLD AIR SCOURS OUT EAST OF THE
MOUNTAINS.

A COLD FRONT WITH STRONG WINDS WILL PRODUCE COLDER
CONDITIONS...LIKELY LATE CHRISTMAS EVE INTO CHRISTMAS DAY. THERE
WILL BE STRONG WESTERLY WINDS AND STRONG WIND GUSTS. SNOW SHOWERS
ARE LIKELY BEHIND THE SYSTEM IN WESTERN AREAS.

THE CHANGEABLE DETAILS...MONDAY THE ENSEMBLE FORECAST SHOWS A
WAVE PASSING TO OUR SOUTH WHICH COULD PRODUCE LIGHT SNOW OR A
MIX...MAINLY IN SOUTHEASTERN AREAS. THE IMPLIED LOW-LEVEL BOUNDARY
IS THE RETREATING COLD AIR TO OUR NORTHEAST AS THE STRONG CYCLONE
TO OUR WEST BEGINS TO TAKE SHAPE. IMPLIED LOW-LEVEL AGEOSTROPHIC
NORTHERLY FLOW HOLDING LOW-LEVEL COLD AIR IN MONDAY INTO TUESDAY.

TUESDAY THE COLD AIR SHOULD CONTINUE TO ERODE. HAD TO KEEP SOME
FREEZE RAIN/DRIZZLE IN NORTHEASTERN AREAS OVERNIGHT MONDAY INTO
TUESDAY BASED ON IMPLIED AGEOSTROPHIC FLOW AND ENSEMBLE
PRECIPITATION TYPES. BUT DURING THE DAY TUESDAY THE WARM AIR
SHOULD WIN OUT. THOUGH ALL SYSTEMS SHOW SOME HINTS OF COLD AIR
DAMMING....DAYTIME HIGHS EAST/NORTHEAST AREAS WILL BE WELL BELOW
WHAT ONE MIGHT EXPECT WITH 6-10C 850 MB TEMPS.

ANY PRECIPITATION TUESDAY AND WEDNESDAY SHOULD BE RAIN MUCH AFTER
NOON TUESDAY IN THE NORTHEAST. PRECIPITATION ON TUESDAY SHOULD BE
LIGHT...ENSEMBLES SHOW PROBABILITIES IN THE 20-30 RANGE AND LIGHT
AMOUNTS. THE PATTERN...SHARP NORTH-SOUTH FRONT TO OUR
WEST...IMPLIES SOME ISOLATED SHOWERS BUT THE MAIN RAIN EVENT
SHOULD WITHIN 3-6 HOURS OF THE FRONT.

TUESDAY THE STRONG CYCLONE...WITH SOME OF THE LOWEST SURFACE
PRESSURES IN THE EASTERN US ON 24 DECEMBER IN THE PAST 30 YEARS
WILL MOVE INTO THE GREAT LAKES. PRESSURE ANOMALIES ARE -3 TO -4
SIGMA BELOW NORMAL WITH A RETURN PERIOD ON THE ORDER OF 30 YEARS
IN SOME FORECAST SYSTEMS.

THE FRONT ASSOCIATED WITH THE CYCLONE PUSHES INTO OUR REGION
WEDNESDAY...AT THIS TIME THE 850 MB SOUTHERLY WINDS ARE FORECAST
TO BE ABOUT +3 SIGMA ABOVE NORMAL. THE STRONG SOUTHERLY FLOW...THE
HIGH PRECIPITABLE WATER...THE STRONG FRONT ALL IMPLY A FRONTAL
RAIN EVENT AND PERHAPS SOME RARE LATE DECEMBER (ELEVATED)
CONVECTION. IF THIS WERE AUTUMN OR SPRING WE MIGHT BE THINKING
QLCS. BUT SURFACE CAPE IS VIRTUALLY NON-EXISTENT BUT SHOWERY RAIN
AND PERHAPS ISOLATED THUNDER POSSIBLE.

DO NOT LIKE HAVING POPS ABOVE 60 TO 66 PERCENT AT DAY 5 IN 12 HOUR
PERIODS. TIMING WILL CLEARLY CHANGE BUT HAVE HIGH POPS FOR
CONSISTENCY WITH OTHER OFFICES.

CHRISTMAS EVE AND EARLY CHRISTMAS IS THE AREA OF HIGH UNCERTAINTY
AS TO WHEN THE COLD AIR COMES IN. THIS WILL DICTATE WHEN THE RAIN
COMES AND WHEN THE GUSTY WINDS SET IN. GRADIENTS ARE WHERE
FORECASTS ARE THEIR POOREST. BUT BY CHRISTMAS MORNING MOST IF NOT
ALL OF THE REGION SHOULD BE BELOW 0C AT 850 AND THE STRONG
WESTERLY WINDS SHOULD BE MIXING DOWN BEHIND THE FRONTAL BOUNDARY.
WINDY OVERNIGHT CHRISTMAS EVE INTO CHRISTMAS DAY. ANY RESIDUAL
PRECIPITATION SHOULD BE SNOW/SNOW SHOWERS AND FLURRIES.

TEMPERATURES SHOULD REBOUND FRIDAY AHEAD OF ANOTHER NORTHERN STREAM
WAVE MOVING INTO THE MID-WEST. THIS SHOULD RAISE OUR HEIGHTS AND
TEMPERATURES FRIDAY INTO EARLY SATURDAY. IT APPEARS A SERIES OF
WAVES MAY EVENTUALLY CARVE OUT A TROUGH OVER THE EAST-CENTRAL US. IF
SO...WE COULD END DECEMBER A BIT ON THE CHILLY SIDE.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
A WEAK AND SHALLOW STRATOCU DECK REMAINS TRAPPED BENEATH
SUBSIDENCE. THE CIG RESTRICTIONS WILL SPREAD AND INCREASE DUE TO
THE STRENGTHENING OF THE INVERSION OVERNIGHT. EXPECT THE
EXPANDING STRATOCU DECK LIKELY TO RETURN AGAIN TONIGHT...THOUGH
LOW CLOUDS SHOULD NOT BE QUITE AS EXPANSIVE AS PREVIOUS NIGHTS. A
SHORTWAVE WILL TRACK ACROSS THE REGION BRINGING A THICKENING MID-
LVL DECK AS WELL. SURFACE WINDS WILL CONTINUE TO BE LIGHT...WITH
SW FLOW ALOFT BEGINNING TO INCREASE AS A LARGE LOW PRESSURE SYSTEM
BEGINS TO DEEPEN OVER THE CENTRAL U.S. EXPECT MVFR CIGS AT THE
CENTRAL SITES AOO AND UNV...WITH IFR POSSIBLE AT BFD AND
JST...WITH MAINLY VFR THROUGH THE EASTERN TAF SITES.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

THU...WINDY AND COLDER WITH SCT MVFR CIGS AND -SHSN.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...FITZGERALD
LONG TERM...GRUMM
AVIATION...DEVOIR/CERU



000
FXUS61 KCTP 210019
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
719 PM EST SAT DEC 20 2014

.SYNOPSIS...
AN AMPLIFYING UPPER RIDGE WILL MOVE INTO THE REGION ON
SUNDAY. TEMPERATURES WILL THEN BECOME JUST SLIGHTLY MILDER BUT
UNSETTLED CONDITIONS WILL BEGIN ON MONDAY NIGHT AND PREVAIL
THROUGH MID WEEK. A VIGOROUS STORM SYSTEM WILL SWEEP ACROSS THE
COMMONWEALTH ON CHRISTMAS EVE BRINGING WIDESPREAD SHOWERS AND A
CHANCE FOR THUNDERSTORMS. WINDY AND COLDER CONDITIONS WILL FOLLOW
WITH SCATTERED SNOW SHOWERS ACROSS THE WEST AND NORTH FOR
CHRISTMAS DAY. MILDER CONDITIONS WILL RETURN LATE THIS WEEK.

&&

.NEAR TERM /UNTIL 7 AM SUNDAY MORNING/...
CLOUDS CONGESTING OVER THE AREA BUT SOME AREAS STILL FREE OF THE
LOWEST DECK. A VIGOROUS SHORT WAVE ROLLING OVERHEAD EARLY TONIGHT
MAY CREATE ENOUGH LIFT AND COULD SEED THE LOWER CLOUDS WITH ICE
CRYSTALS FROM ABOVE. THUS...SOME FLURRIES ARE EXPECTED OVER THE
LAURELS AND ALONG THE NRN TIER. WILL LEAVE ACCUMS OUT OF THE FCST
FOR NOW. MINS PROBABLY A HOMOGENEOUS 20-25F ACROSS THE BOARD.

&&

.SHORT TERM /7 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
DEEP LAYER DRYING BEHIND A DEPARTING 5H WAVE AND UPPER LEVEL
RIDGING HAS THE POTENTIAL TO BRING SUNSHINE TO MOST IF NOT ALL OF
CENTRAL PA ON MONDAY. THE STUBBORN STRATUS THAT HAS PLAGUED US FOR
MORE THAN A WEEK WILL HAVE A CHANCE TO MIX OUT...BUT TRANSITORY
SFC HIGH PRESSURE MAY STILL MAKE THIS A SLOW PROCESS OVER THE
NORTH.

PRIOR TO THAT...SOME AREAS COULD PERHAPS SEE A FLURRY IN THE PRE
DAWN HOURS SUNDAY BEFORE THE WAVE QUICKLY EXITS EASTWARD. WENT
CLOSE TO CONSALL GUIDANCE AGAIN WITH MAXES REACHING THE MID TO
UPPER 30S NORTH TO THE LOWER 40S SOUTH.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
THE MOST SIGNIFICANT FORECAST ISSUE IN THE LONG TERM IS THE
EVOLUTION OF THE MASSIVE CYCLONE TO OUR WEST 23-25 DECEMBER.
STRONG SOUTHERLY FLOW AHEAD OF THIS SYSTEM WILL BRING WARM AIR
INTO THE REGION LATE MONDAY INTO TUESDAY. BY TUESDAY AND WEDNESDAY
MANY LOW- LEVEL TEMPERATURE AND MOISTURE FIELDS WILL BE WELL ABOVE
THEIR SEASONAL VALUES. THIS IMPLIES VERY WARM WEATHER TUESDAY AND
WEDNESDAY...WHEN THE SHALLOW COLD AIR SCOURS OUT EAST OF THE
MOUNTAINS.

A COLD FRONT WITH STRONG WINDS WILL PRODUCE COLDER
CONDITIONS...LIKELY LATE CHRISTMAS EVE INTO CHRISTMAS DAY. THERE
WILL BE STRONG WESTERLY WINDS AND STRONG WIND GUSTS. SNOW SHOWERS
ARE LIKELY BEHIND THE SYSTEM IN WESTERN AREAS.

THE CHANGEABLE DETAILS...MONDAY THE ENSEMBLE FORECAST SHOWS A
WAVE PASSING TO OUR SOUTH WHICH COULD PRODUCE LIGHT SNOW OR A
MIX...MAINLY IN SOUTHEASTERN AREAS. THE IMPLIED LOW-LEVEL BOUNDARY
IS THE RETREATING COLD AIR TO OUR NORTHEAST AS THE STRONG CYCLONE
TO OUR WEST BEGINS TO TAKE SHAPE. IMPLIED LOW-LEVEL AGEOSTROPHIC
NORTHERLY FLOW HOLDING LOW-LEVEL COLD AIR IN MONDAY INTO TUESDAY.

TUESDAY THE COLD AIR SHOULD CONTINUE TO ERODE. HAD TO KEEP SOME
FREEZE RAIN/DRIZZLE IN NORTHEASTERN AREAS OVERNIGHT MONDAY INTO
TUESDAY BASED ON IMPLIED AGEOSTROPHIC FLOW AND ENSEMBLE
PRECIPITATION TYPES. BUT DURING THE DAY TUESDAY THE WARM AIR
SHOULD WIN OUT. THOUGH ALL SYSTEMS SHOW SOME HINTS OF COLD AIR
DAMMING....DAYTIME HIGHS EAST/NORTHEAST AREAS WILL BE WELL BELOW
WHAT ONE MIGHT EXPECT WITH 6-10C 850 MB TEMPS.

ANY PRECIPITATION TUESDAY AND WEDNESDAY SHOULD BE RAIN MUCH AFTER
NOON TUESDAY IN THE NORTHEAST. PRECIPITATION ON TUESDAY SHOULD BE
LIGHT...ENSEMBLES SHOW PROBABILITIES IN THE 20-30 RANGE AND LIGHT
AMOUNTS. THE PATTERN...SHARP NORTH-SOUTH FRONT TO OUR
WEST...IMPLIES SOME ISOLATED SHOWERS BUT THE MAIN RAIN EVENT
SHOULD WITHIN 3-6 HOURS OF THE FRONT.

TUESDAY THE STRONG CYCLONE...WITH SOME OF THE LOWEST SURFACE
PRESSURES IN THE EASTERN US ON 24 DECEMBER IN THE PAST 30 YEARS
WILL MOVE INTO THE GREAT LAKES. PRESSURE ANOMALIES ARE -3 TO -4
SIGMA BELOW NORMAL WITH A RETURN PERIOD ON THE ORDER OF 30 YEARS
IN SOME FORECAST SYSTEMS.

THE FRONT ASSOCIATED WITH THE CYCLONE PUSHES INTO OUR REGION
WEDNESDAY...AT THIS TIME THE 850 MB SOUTHERLY WINDS ARE FORECAST
TO BE ABOUT +3 SIGMA ABOVE NORMAL. THE STRONG SOUTHERLY FLOW...THE
HIGH PRECIPITABLE WATER...THE STRONG FRONT ALL IMPLY A FRONTAL
RAIN EVENT AND PERHAPS SOME RARE LATE DECEMBER (ELEVATED)
CONVECTION. IF THIS WERE AUTUMN OR SPRING WE MIGHT BE THINKING
QLCS. BUT SURFACE CAPE IS VIRTUALLY NON-EXISTENT BUT SHOWERY RAIN
AND PERHAPS ISOLATED THUNDER POSSIBLE.

DO NOT LIKE HAVING POPS ABOVE 60 TO 66 PERCENT AT DAY 5 IN 12 HOUR
PERIODS. TIMING WILL CLEARLY CHANGE BUT HAVE HIGH POPS FOR
CONSISTENCY WITH OTHER OFFICES.

CHRISTMAS EVE AND EARLY CHRISTMAS IS THE AREA OF HIGH UNCERTAINTY
AS TO WHEN THE COLD AIR COMES IN. THIS WILL DICTATE WHEN THE RAIN
COMES AND WHEN THE GUSTY WINDS SET IN. GRADIENTS ARE WHERE
FORECASTS ARE THEIR POOREST. BUT BY CHRISTMAS MORNING MOST IF NOT
ALL OF THE REGION SHOULD BE BELOW 0C AT 850 AND THE STRONG
WESTERLY WINDS SHOULD BE MIXING DOWN BEHIND THE FRONTAL BOUNDARY.
WINDY OVERNIGHT CHRISTMAS EVE INTO CHRISTMAS DAY. ANY RESIDUAL
PRECIPITATION SHOULD BE SNOW/SNOW SHOWERS AND FLURRIES.

TEMPERATURES SHOULD REBOUND FRIDAY AHEAD OF ANOTHER NORTHERN STREAM
WAVE MOVING INTO THE MID-WEST. THIS SHOULD RAISE OUR HEIGHTS AND
TEMPERATURES FRIDAY INTO EARLY SATURDAY. IT APPEARS A SERIES OF
WAVES MAY EVENTUALLY CARVE OUT A TROUGH OVER THE EAST-CENTRAL US. IF
SO...WE COULD END DECEMBER A BIT ON THE CHILLY SIDE.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
A WEAK AND SHALLOW STRATOCU DECK REMAINS TRAPPED BENEATH
SUBSIDENCE. THE CIG RESTRICTIONS WILL SPREAD AND INCREASE DUE TO
THE STRENGTHENING OF THE INVERSION OVERNIGHT. EXPECT THE
EXPANDING STRATOCU DECK LIKELY TO RETURN AGAIN TONIGHT...THOUGH
LOW CLOUDS SHOULD NOT BE QUITE AS EXPANSIVE AS PREVIOUS NIGHTS. A
SHORTWAVE WILL TRACK ACROSS THE REGION BRINGING A THICKENING MID-
LVL DECK AS WELL. SURFACE WINDS WILL CONTINUE TO BE LIGHT...WITH
SW FLOW ALOFT BEGINNING TO INCREASE AS A LARGE LOW PRESSURE SYSTEM
BEGINS TO DEEPEN OVER THE CENTRAL U.S. EXPECT MVFR CIGS AT THE
CENTRAL SITES AOO AND UNV...WITH IFR POSSIBLE AT BFD AND
JST...WITH MAINLY VFR THROUGH THE EASTERN TAF SITES.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

THU...WINDY AND COLDER WITH SCT MVFR CIGS AND -SHSN.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...FITZGERALD
LONG TERM...GRUMM
AVIATION...DEVOIR/CERU



000
FXUS61 KCTP 210001
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
701 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE SLIDING EASTWARD THROUGH QUEBEC WITH A SECOND HIGH
PRESSURE CELL OVER THE EASTERN GREAT LAKES AND OHIO VALLEY WILL
KEEP MAINTAIN DRY WEATHER ACROSS CENTRAL PENNSYLVANIA FOR THE REST
OF THIS WEEKEND. AN AMPLIFYING UPPER RIDGE MOVING INTO THE REGION
WILL BRING INCREASING AMOUNTS OF SUNSHINE ON SUNDAY...BUT WILL BE
QUICKLY REPLACED BY A LARGE STORM SYSTEM TRACKING ACROSS THE
CENTRAL UNITED STATES. MOISTURE ASSOCIATED WITH THAT STORM AND
INCREASING EAST FLOW OFF OF THE WESTERN ATLANTIC WILL BRING
INCREASING CLOUDS ON MONDAY...WITH QUITE MILD BUT UNSETTLED
CONDITIONS PREVAILING THROUGH MID WEEK. A VIGOROUS STORM SYSTEM
WILL SWEEP ACROSS THE COMMONWEALTH ON CHRISTMAS EVE BRINGING
WIDESPREAD SHOWERS AND A CHANCE FOR THUNDERSTORMS...FOLLOWED BY
WINDY AND COLDER CONDITIONS WITH SCATTERED SNOW SHOWERS AND
FLURRIES ACROSS THE WEST AND NORTH FOR CHRISTMAS DAY. MILDER
CONDITIONS WILL ARRIVE ONCE AGAIN BY LATE THIS WEEK.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
SUBSIDENCE AND DOWNSLOPING OVER MUCH OF THE LAUREL HIGHLANDS AND
PARTS OF THE CENTRAL AND SOUTH CENTRAL MOUNTAINS IS BRINGING SOME
MUCH NEEDED SUNSHINE TO THOSE AREAS. VISIBLE IMAGERY INDICATES THE
NORTHWARD EXTENT PUSHING TOWARDS CENTRAL CLEARFIELD COUNTY AND
SOUTHERN CENTRE COUNTY...AND IT APPEARS LIKELY TO REACH A LITTLE
FARTHER NORTH BEFORE SUNSET.

EXPECT CLOUDS TO FILL BACK IN OVERNIGHT...AS 5H WAVE TRACKS ACROSS
THE OHIO VALLEY AND INTO SOUTHWEST PA BY 12Z SUN. MINS WILL BE
FAIRLY UNIFORM AND RANGE FROM THE LOWER 20S NORTH TO THE UPPER 20S
SOUTHEAST.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
DEEP LAYER DRYING BEHIND THE AFOREMENTIONED DEPARTING 5H WAVE AND
UPPER LEVEL RIDGING HAS THE POTENTIAL TO BRING SUNSHINE TO MOST IF
NOT ALL OF CENTRAL PA ON MONDAY. THE STUBBORN STRATUS THAT HAS
PLAGUED US FOR MORE THAN A WEEK WILL HAVE A CHANCE TO MIX
OUT...BUT TRANSITORY SFC HIGH PRESSURE MAY STILL MAKE THIS A SLOW
PROCESS OVER THE NORTH.

PRIOR TO THAT...SOME AREAS COULD PERHAPS SEE A FLURRY IN THE PRE
DAWN HOURS SUNDAY BEFORE THE WAVE QUICKLY EXITS EASTWARD. WENT
CLOSE TO CONSALL GUIDANCE AGAIN WITH MAXES REACHING THE MID TO
UPPER 30S NORTH TO THE LOWER 40S SOUTH.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
THE MOST SIGNIFICANT FORECAST ISSUE IN THE LONG TERM IS THE
EVOLUTION OF THE MASSIVE CYCLONE TO OUR WEST 23-25 DECEMBER.
STRONG SOUTHERLY FLOW AHEAD OF THIS SYSTEM WILL BRING WARM AIR
INTO THE REGION LATE MONDAY INTO TUESDAY. BY TUESDAY AND WEDNESDAY
MANY LOW- LEVEL TEMPERATURE AND MOISTURE FIELDS WILL BE WELL ABOVE
THEIR SEASONAL VALUES. THIS IMPLIES VERY WARM WEATHER TUESDAY AND
WEDNESDAY...WHEN THE SHALLOW COLD AIR SCOURS OUT EAST OF THE
MOUNTAINS.

A COLD FRONT WITH STRONG WINDS WILL PRODUCE COLDER
CONDITIONS...LIKELY LATE CHRISTMAS EVE INTO CHRISTMAS DAY. THERE
WILL BE STRONG WESTERLY WINDS AND STRONG WIND GUSTS. SNOW SHOWERS
ARE LIKELY BEHIND THE SYSTEM IN WESTERN AREAS.

THE CHANGEABLE DETAILS...MONDAY THE ENSEMBLE FORECAST SHOWS A
WAVE PASSING TO OUR SOUTH WHICH COULD PRODUCE LIGHT SNOW OR A
MIX...MAINLY IN SOUTHEASTERN AREAS. THE IMPLIED LOW-LEVEL BOUNDARY
IS THE RETREATING COLD AIR TO OUR NORTHEAST AS THE STRONG CYCLONE
TO OUR WEST BEGINS TO TAKE SHAPE. IMPLIED LOW-LEVEL AGEOSTROPHIC
NORTHERLY FLOW HOLDING LOW-LEVEL COLD AIR IN MONDAY INTO TUESDAY.

TUESDAY THE COLD AIR SHOULD CONTINUE TO ERODE. HAD TO KEEP SOME
FREEZE RAIN/DRIZZLE IN NORTHEASTERN AREAS OVERNIGHT MONDAY INTO
TUESDAY BASED ON IMPLIED AGEOSTROPHIC FLOW AND ENSEMBLE
PRECIPITATION TYPES. BUT DURING THE DAY TUESDAY THE WARM AIR
SHOULD WIN OUT. THOUGH ALL SYSTEMS SHOW SOME HINTS OF COLD AIR
DAMMING....DAYTIME HIGHS EAST/NORTHEAST AREAS WILL BE WELL BELOW
WHAT ONE MIGHT EXPECT WITH 6-10C 850 MB TEMPS.

ANY PRECIPITATION TUESDAY AND WEDNESDAY SHOULD BE RAIN MUCH AFTER
NOON TUESDAY IN THE NORTHEAST. PRECIPITATION ON TUESDAY SHOULD BE
LIGHT...ENSEMBLES SHOW PROBABILITIES IN THE 20-30 RANGE AND LIGHT
AMOUNTS. THE PATTERN...SHARP NORTH-SOUTH FRONT TO OUR
WEST...IMPLIES SOME ISOLATED SHOWERS BUT THE MAIN RAIN EVENT
SHOULD WITHIN 3-6 HOURS OF THE FRONT.

TUESDAY THE STRONG CYCLONE...WITH SOME OF THE LOWEST SURFACE
PRESSURES IN THE EASTERN US ON 24 DECEMBER IN THE PAST 30 YEARS
WILL MOVE INTO THE GREAT LAKES. PRESSURE ANOMALIES ARE -3 TO -4
SIGMA BELOW NORMAL WITH A RETURN PERIOD ON THE ORDER OF 30 YEARS
IN SOME FORECAST SYSTEMS.

THE FRONT ASSOCIATED WITH THE CYCLONE PUSHES INTO OUR REGION
WEDNESDAY...AT THIS TIME THE 850 MB SOUTHERLY WINDS ARE FORECAST
TO BE ABOUT +3 SIGMA ABOVE NORMAL. THE STRONG SOUTHERLY FLOW...THE
HIGH PRECIPITABLE WATER...THE STRONG FRONT ALL IMPLY A FRONTAL
RAIN EVENT AND PERHAPS SOME RARE LATE DECEMBER (ELEVATED)
CONVECTION. IF THIS WERE AUTUMN OR SPRING WE MIGHT BE THINKING
QLCS. BUT SURFACE CAPE IS VIRTUALLY NON-EXISTENT BUT SHOWERY RAIN
AND PERHAPS ISOLATED THUNDER POSSIBLE.

DO NOT LIKE HAVING POPS ABOVE 60 TO 66 PERCENT AT DAY 5 IN 12 HOUR
PERIODS. TIMING WILL CLEARLY CHANGE BUT HAVE HIGH POPS FOR
CONSISTENCY WITH OTHER OFFICES.

CHRISTMAS EVE AND EARLY CHRISTMAS IS THE AREA OF HIGH UNCERTAINTY
AS TO WHEN THE COLD AIR COMES IN. THIS WILL DICTATE WHEN THE RAIN
COMES AND WHEN THE GUSTY WINDS SET IN. GRADIENTS ARE WHERE
FORECASTS ARE THEIR POOREST. BUT BY CHRISTMAS MORNING MOST IF NOT
ALL OF THE REGION SHOULD BE BELOW 0C AT 850 AND THE STRONG
WESTERLY WINDS SHOULD BE MIXING DOWN BEHIND THE FRONTAL BOUNDARY.
WINDY OVERNIGHT CHRISTMAS EVE INTO CHRISTMAS DAY. ANY RESIDUAL
PRECIPITATION SHOULD BE SNOW/SNOW SHOWERS AND FLURRIES.

TEMPERATURES SHOULD REBOUND FRIDAY AHEAD OF ANOTHER NORTHERN STREAM
WAVE MOVING INTO THE MID-WEST. THIS SHOULD RAISE OUR HEIGHTS AND
TEMPERATURES FRIDAY INTO EARLY SATURDAY. IT APPEARS A SERIES OF
WAVES MAY EVENTUALLY CARVE OUT A TROUGH OVER THE EAST-CENTRAL US. IF
SO...WE COULD END DECEMBER A BIT ON THE CHILLY SIDE.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
 A WEAK AND SHALLOW STRATOCU DECK REMAINS TRAPPED BENEATH
SUBSIDENCE. THE CIG RESTRICTIONS WILL SPREAD AND INCREASE DUE TO
THE STRENGTHENING OF THE INVERSION OVERNIGHT. EXPECT THE
EXPANDING STRATOCU DECK LIKELY TO RETURN AGAIN TONIGHT...THOUGH
LOW CLOUDS SHOULD NOT BE QUITE AS EXPANSIVE AS PREVIOUS NIGHTS. A
SHORTWAVE WILL TRACK ACROSS THE REGION BRINGING A THICKENING MID-
LVL DECK AS WELL. SURFACE WINDS WILL CONTINUE TO BE LIGHT...WITH
SW FLOW ALOFT BEGINNING TO INCREASE AS A LARGE LOW PRESSURE SYSTEM
BEGINS TO DEEPEN OVER THE CENTRAL U.S. EXPECT MVFR CIGS AT THE
CENTRAL SITES AOO AND UNV...WITH IFR POSSIBLE AT BFD AND
JST...WITH MAINLY VFR THROUGH THE EASTERN TAF SITES.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

THU...WINDY AND COLDER WITH SCT MVFR CIGS AND -SHSN.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...DEVOIR/FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...GRUMM
AVIATION...DEVOIR/CERU




000
FXUS61 KCTP 210001
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
701 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE SLIDING EASTWARD THROUGH QUEBEC WITH A SECOND HIGH
PRESSURE CELL OVER THE EASTERN GREAT LAKES AND OHIO VALLEY WILL
KEEP MAINTAIN DRY WEATHER ACROSS CENTRAL PENNSYLVANIA FOR THE REST
OF THIS WEEKEND. AN AMPLIFYING UPPER RIDGE MOVING INTO THE REGION
WILL BRING INCREASING AMOUNTS OF SUNSHINE ON SUNDAY...BUT WILL BE
QUICKLY REPLACED BY A LARGE STORM SYSTEM TRACKING ACROSS THE
CENTRAL UNITED STATES. MOISTURE ASSOCIATED WITH THAT STORM AND
INCREASING EAST FLOW OFF OF THE WESTERN ATLANTIC WILL BRING
INCREASING CLOUDS ON MONDAY...WITH QUITE MILD BUT UNSETTLED
CONDITIONS PREVAILING THROUGH MID WEEK. A VIGOROUS STORM SYSTEM
WILL SWEEP ACROSS THE COMMONWEALTH ON CHRISTMAS EVE BRINGING
WIDESPREAD SHOWERS AND A CHANCE FOR THUNDERSTORMS...FOLLOWED BY
WINDY AND COLDER CONDITIONS WITH SCATTERED SNOW SHOWERS AND
FLURRIES ACROSS THE WEST AND NORTH FOR CHRISTMAS DAY. MILDER
CONDITIONS WILL ARRIVE ONCE AGAIN BY LATE THIS WEEK.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
SUBSIDENCE AND DOWNSLOPING OVER MUCH OF THE LAUREL HIGHLANDS AND
PARTS OF THE CENTRAL AND SOUTH CENTRAL MOUNTAINS IS BRINGING SOME
MUCH NEEDED SUNSHINE TO THOSE AREAS. VISIBLE IMAGERY INDICATES THE
NORTHWARD EXTENT PUSHING TOWARDS CENTRAL CLEARFIELD COUNTY AND
SOUTHERN CENTRE COUNTY...AND IT APPEARS LIKELY TO REACH A LITTLE
FARTHER NORTH BEFORE SUNSET.

EXPECT CLOUDS TO FILL BACK IN OVERNIGHT...AS 5H WAVE TRACKS ACROSS
THE OHIO VALLEY AND INTO SOUTHWEST PA BY 12Z SUN. MINS WILL BE
FAIRLY UNIFORM AND RANGE FROM THE LOWER 20S NORTH TO THE UPPER 20S
SOUTHEAST.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
DEEP LAYER DRYING BEHIND THE AFOREMENTIONED DEPARTING 5H WAVE AND
UPPER LEVEL RIDGING HAS THE POTENTIAL TO BRING SUNSHINE TO MOST IF
NOT ALL OF CENTRAL PA ON MONDAY. THE STUBBORN STRATUS THAT HAS
PLAGUED US FOR MORE THAN A WEEK WILL HAVE A CHANCE TO MIX
OUT...BUT TRANSITORY SFC HIGH PRESSURE MAY STILL MAKE THIS A SLOW
PROCESS OVER THE NORTH.

PRIOR TO THAT...SOME AREAS COULD PERHAPS SEE A FLURRY IN THE PRE
DAWN HOURS SUNDAY BEFORE THE WAVE QUICKLY EXITS EASTWARD. WENT
CLOSE TO CONSALL GUIDANCE AGAIN WITH MAXES REACHING THE MID TO
UPPER 30S NORTH TO THE LOWER 40S SOUTH.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
THE MOST SIGNIFICANT FORECAST ISSUE IN THE LONG TERM IS THE
EVOLUTION OF THE MASSIVE CYCLONE TO OUR WEST 23-25 DECEMBER.
STRONG SOUTHERLY FLOW AHEAD OF THIS SYSTEM WILL BRING WARM AIR
INTO THE REGION LATE MONDAY INTO TUESDAY. BY TUESDAY AND WEDNESDAY
MANY LOW- LEVEL TEMPERATURE AND MOISTURE FIELDS WILL BE WELL ABOVE
THEIR SEASONAL VALUES. THIS IMPLIES VERY WARM WEATHER TUESDAY AND
WEDNESDAY...WHEN THE SHALLOW COLD AIR SCOURS OUT EAST OF THE
MOUNTAINS.

A COLD FRONT WITH STRONG WINDS WILL PRODUCE COLDER
CONDITIONS...LIKELY LATE CHRISTMAS EVE INTO CHRISTMAS DAY. THERE
WILL BE STRONG WESTERLY WINDS AND STRONG WIND GUSTS. SNOW SHOWERS
ARE LIKELY BEHIND THE SYSTEM IN WESTERN AREAS.

THE CHANGEABLE DETAILS...MONDAY THE ENSEMBLE FORECAST SHOWS A
WAVE PASSING TO OUR SOUTH WHICH COULD PRODUCE LIGHT SNOW OR A
MIX...MAINLY IN SOUTHEASTERN AREAS. THE IMPLIED LOW-LEVEL BOUNDARY
IS THE RETREATING COLD AIR TO OUR NORTHEAST AS THE STRONG CYCLONE
TO OUR WEST BEGINS TO TAKE SHAPE. IMPLIED LOW-LEVEL AGEOSTROPHIC
NORTHERLY FLOW HOLDING LOW-LEVEL COLD AIR IN MONDAY INTO TUESDAY.

TUESDAY THE COLD AIR SHOULD CONTINUE TO ERODE. HAD TO KEEP SOME
FREEZE RAIN/DRIZZLE IN NORTHEASTERN AREAS OVERNIGHT MONDAY INTO
TUESDAY BASED ON IMPLIED AGEOSTROPHIC FLOW AND ENSEMBLE
PRECIPITATION TYPES. BUT DURING THE DAY TUESDAY THE WARM AIR
SHOULD WIN OUT. THOUGH ALL SYSTEMS SHOW SOME HINTS OF COLD AIR
DAMMING....DAYTIME HIGHS EAST/NORTHEAST AREAS WILL BE WELL BELOW
WHAT ONE MIGHT EXPECT WITH 6-10C 850 MB TEMPS.

ANY PRECIPITATION TUESDAY AND WEDNESDAY SHOULD BE RAIN MUCH AFTER
NOON TUESDAY IN THE NORTHEAST. PRECIPITATION ON TUESDAY SHOULD BE
LIGHT...ENSEMBLES SHOW PROBABILITIES IN THE 20-30 RANGE AND LIGHT
AMOUNTS. THE PATTERN...SHARP NORTH-SOUTH FRONT TO OUR
WEST...IMPLIES SOME ISOLATED SHOWERS BUT THE MAIN RAIN EVENT
SHOULD WITHIN 3-6 HOURS OF THE FRONT.

TUESDAY THE STRONG CYCLONE...WITH SOME OF THE LOWEST SURFACE
PRESSURES IN THE EASTERN US ON 24 DECEMBER IN THE PAST 30 YEARS
WILL MOVE INTO THE GREAT LAKES. PRESSURE ANOMALIES ARE -3 TO -4
SIGMA BELOW NORMAL WITH A RETURN PERIOD ON THE ORDER OF 30 YEARS
IN SOME FORECAST SYSTEMS.

THE FRONT ASSOCIATED WITH THE CYCLONE PUSHES INTO OUR REGION
WEDNESDAY...AT THIS TIME THE 850 MB SOUTHERLY WINDS ARE FORECAST
TO BE ABOUT +3 SIGMA ABOVE NORMAL. THE STRONG SOUTHERLY FLOW...THE
HIGH PRECIPITABLE WATER...THE STRONG FRONT ALL IMPLY A FRONTAL
RAIN EVENT AND PERHAPS SOME RARE LATE DECEMBER (ELEVATED)
CONVECTION. IF THIS WERE AUTUMN OR SPRING WE MIGHT BE THINKING
QLCS. BUT SURFACE CAPE IS VIRTUALLY NON-EXISTENT BUT SHOWERY RAIN
AND PERHAPS ISOLATED THUNDER POSSIBLE.

DO NOT LIKE HAVING POPS ABOVE 60 TO 66 PERCENT AT DAY 5 IN 12 HOUR
PERIODS. TIMING WILL CLEARLY CHANGE BUT HAVE HIGH POPS FOR
CONSISTENCY WITH OTHER OFFICES.

CHRISTMAS EVE AND EARLY CHRISTMAS IS THE AREA OF HIGH UNCERTAINTY
AS TO WHEN THE COLD AIR COMES IN. THIS WILL DICTATE WHEN THE RAIN
COMES AND WHEN THE GUSTY WINDS SET IN. GRADIENTS ARE WHERE
FORECASTS ARE THEIR POOREST. BUT BY CHRISTMAS MORNING MOST IF NOT
ALL OF THE REGION SHOULD BE BELOW 0C AT 850 AND THE STRONG
WESTERLY WINDS SHOULD BE MIXING DOWN BEHIND THE FRONTAL BOUNDARY.
WINDY OVERNIGHT CHRISTMAS EVE INTO CHRISTMAS DAY. ANY RESIDUAL
PRECIPITATION SHOULD BE SNOW/SNOW SHOWERS AND FLURRIES.

TEMPERATURES SHOULD REBOUND FRIDAY AHEAD OF ANOTHER NORTHERN STREAM
WAVE MOVING INTO THE MID-WEST. THIS SHOULD RAISE OUR HEIGHTS AND
TEMPERATURES FRIDAY INTO EARLY SATURDAY. IT APPEARS A SERIES OF
WAVES MAY EVENTUALLY CARVE OUT A TROUGH OVER THE EAST-CENTRAL US. IF
SO...WE COULD END DECEMBER A BIT ON THE CHILLY SIDE.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
 A WEAK AND SHALLOW STRATOCU DECK REMAINS TRAPPED BENEATH
SUBSIDENCE. THE CIG RESTRICTIONS WILL SPREAD AND INCREASE DUE TO
THE STRENGTHENING OF THE INVERSION OVERNIGHT. EXPECT THE
EXPANDING STRATOCU DECK LIKELY TO RETURN AGAIN TONIGHT...THOUGH
LOW CLOUDS SHOULD NOT BE QUITE AS EXPANSIVE AS PREVIOUS NIGHTS. A
SHORTWAVE WILL TRACK ACROSS THE REGION BRINGING A THICKENING MID-
LVL DECK AS WELL. SURFACE WINDS WILL CONTINUE TO BE LIGHT...WITH
SW FLOW ALOFT BEGINNING TO INCREASE AS A LARGE LOW PRESSURE SYSTEM
BEGINS TO DEEPEN OVER THE CENTRAL U.S. EXPECT MVFR CIGS AT THE
CENTRAL SITES AOO AND UNV...WITH IFR POSSIBLE AT BFD AND
JST...WITH MAINLY VFR THROUGH THE EASTERN TAF SITES.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

THU...WINDY AND COLDER WITH SCT MVFR CIGS AND -SHSN.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...DEVOIR/FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...GRUMM
AVIATION...DEVOIR/CERU



000
FXUS61 KPBZ 202323
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
623 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE WILL BE IN CONTROL INTO MONDAY. EXPECT INCREASING
PRECIPITATION CHANCES TUESDAY. STORM SYSTEM BRINGS RAIN AND WIND
CHRISTMAS EVE...AND SNOW SHOWERS CHRISTMAS DAY.

&&

.NEAR TERM /THROUGH SUNDAY/...
WITH 615PM UPDATE...LOWER CLOUDS REMAIN SCATTERED OUT FROM
PITTSBURGH TO LATROBE AND MORGANTOWN...BUT DO NOT EXPECT THIS TO
PERSIST THROUGH THE EVENING. MINIMAL CHANGES WERE NEEDED TO HOURLY
TEMPERATURE TRENDS. PREVIOUS DISCUSSION FOLLOWS.

WEAKER INVERSION ACROSS PORTIONS OF SOUTHERN PA HAS ALLOWED LOWER
CLOUDS TO BREAK UP SOMEWHAT...ALTHOUGH THEY ARE HANGING TOUGH SO FAR
ACROSS THE NORTHERN COUNTIES NEAR FKL/DUJ AS WELL AS IN SOUTHEAST
OHIO.  EXPECT THESE TO REFORM TONIGHT AS INVERSION SHARPENS UP AGAIN
IN VERY WEAK FLOW...THUS GOING MOSTLY CLOUDY MOST AREAS.  GOING TO HANG
ON TO SLIGHT CHANCE POPS IN THE SOUTHEAST WITH SHORTWAVE TROUGH
MOVING ACROSS AND SLIGHTLY BETTER MOISTURE PROFILE...BUT SNOW
ACCUMULATION IS NOT EXPECTED.  THIS POSSIBILITY ENDS BY 09Z. ONLY
MINOR MODIFICATION TO GENERALLY SEASONABLE TEMPERATURES.

INVERSION IS MAINTAINED SUNDAY MORNING...BUT BY AFTERNOON EXPECT
STRATUS TO MIX OUT INTO A CU FIELD AND THEN SCATTER OUT BY EVENING.
A BIT MORE SUN SHOULD ALLOW FOR AFTERNOON HIGH TEMPS AROUND 5
DEGREES WARMER THAN TODAY. CL

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
BENIGN WEATHER INITIALLY WITH HIGH PRESSURE TO OUR EAST AND IN
CONTROL.  SOUTHEAST WINDS IN RESPONSE TO SURFACE ANTICYCLONE
POSITION WILL FACILITATE DEVELOPMENT OF STRATUS OVER EASTERN
PORTIONS OF TUCKER AND GARRETT COUNTIES MONDAY INTO MONDAY NIGHT.
PCPN ONSET HAS SLOWED DOWN FROM PREVIOUS CYCLES...BUT THERE REMAINS
A VERY LOW PROBABILITY OF FREEZING RAIN AND/OR SLEET OVER
AFOREMENTIONED AREAS MONDAY.  FOR NOW...TRENDED FORECAST WITH PCPN
COMMENCING DURING THE AFTERNOON WHICH REFLECT LATEST NUMERICAL
MODELS.  WITH THIS SCENARIO...LOW LEVEL SUB-FREEZING AIR SHOULD
SCOUR OUT YIELDING AN ALL RAIN PTYPE.

RAIN SHADOW EFFECT TAKES PLACES TUESDAY WITH SOUTHEAST WINDS
WIDESPREAD OVER THE REGION. AN ISOLATED SHOWER REACHING EASTERN OHIO
AND FAR NWRN PA IS NOT OUT OF THE QUESTION...SO KEPT A SLIGHT
CHANCE.  WOULD NOT BE SURPRISED TO SEE BREAKS IN THE CLOUDS WHICH
COULD ALLOW FOR A FEW LOCATIONS TO EXCEED 60 DEGREES.  RECORD HIGHS
FOR PITTSBURGH...MORGANTOWN...AND ZANESVILLE ALL RESIDE WELL INTO
THE UPPER 60S...SO AT THIS JUNCTURE RECORD WARMTH IS NOT FORESEEN.
PRECIP ASSOCIATED WITH THE SURFACE LOW PRESSURE SYSTEM EJECTING FROM
THE GULF COAST REGION REACHES SERN AREAS OF THE FORECAST AREA THAT
EVENING.

A BLEND OF THE ONGOING FORECAST AND BIAS CORRECTED ECMWF WERE USED
FOR TEMPERATURES.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
HIGHLIGHTS:
- A WET CHRISTMAS EVE
- TEMPERATURES RETURN BACK TO NORMAL VALUES CHRISTMAS DAY
- SLIGHTLY ABOVE NORMAL TEMPERATURES RETURN BY FRIDAY

STRONG LOW PRESSURE SYSTEM THAT HAS BEEN MUCH ADVERTISED GIVEN THE
TIME PERIOD WHICH IT AFFECTS OUR AREA IS STILL ON TRACK.  LONG RANGE
ENSEMBLE PREDICTION SYSTEMS AND OPERATIONAL MODELS ARE CONVERGING ON
A TRACK THROUGH IND / ILL THEN NORTH INTO CANADA.  THIS WILL MAKE
FOR ALL LIQUID PRECIPITATION ON THE FRONT END.  TEMPERATURES WILL
SOAR TO NEARLY 20 DEGREES ABOVE NORMAL WEDNESDAY WITH 50S COMMON.
COUPLED WITH INFLUX OF MOISTURE FROM THE GULF OF MEXICO...SOUNDINGS
ILLUSTRATE ELEVATED INSTABILITY WHICH PUSHES TEMP DIFFERENTIAL
BETWEEN H8 AND H5 TO NEARLY 0C.  THIS COULD LEAD TO ISOLATED
THUNDERSTORMS AHEAD OF THE BAROCLINIC ZONE.  FOR THE TIME
BEING...OPTED TO LEAVE THUNDER OUT OF THE FORECAST AND WAIT FOR
BETTER CONTINUITY GIVEN THIS STILL IS FIVE DAYS OUT.  DESPITE PWATS
NEARLY TWO STANDARD DEVIATIONS ABOVE NORMAL...COMBINATION OF
KATABATIC WINDS AND DRY CONVEYOR BELT WILL LIMIT QPF POTENTIAL TO
NEGATE ANY FLOOD THREAT.  LONG RANGE HYDROLOGIC MODELS SHOW VERY
LITTLE RISE IN AREA RIVERS...WHICH CORRELATES WELL TO THE PROJECTED
QPF OF 0.50 TO 1.00".

WITH THE TRACK OF THE CYCLONE DUE N...COLD AIR INJECTED INTO THE
AREA WILL BE OF MIDWEST ORIGIN...SO TEMPS WILL RETREAT BACK TO
SEASONAL BENCHMARKS CHRISTMAS DAY.  FOR THOSE WHO ARE LOOKING FOR
SNOW ON CHRISTMAS...A CHANCE OF SNOW SHOWERS EXIST...BUT GIVEN
TRAJECTORY FROM THE SOUTHWEST ANY ACCUMULATION ASSOCIATED WITH THE
UPPER LEVEL SYSTEM WILL BE LIGHT AT BEST.  HISTORICALLY...THERE IS
ONLY A 17 PERCENT CHANCE OF AT LEAST ONE INCH OF SNOW ON THE GROUND
AT PITTSBURGH CHRISTMAS MORNING.

H8 WINDS PUSH 50KTS WEDNESDAY NIGHT INTO THURSDAY AND HIGHEST
ANOMALIES RESIDE ALONG THE LAKE SHORE...SO EXPECT HIGHEST GUSTS
WOULD DO SO AS WELL.  NONETHELESS...PERIOD FROM WEDNESDAY NIGHT INTO
THURSDAY STRONG ISALLOBARIC FLOW COULD YIELD GUSTS IN EXCESS OF 40
MPH ESPECIALLY IN THE MOUNTAINS OF WRN MD AND NRN WV.

BALANCE OF THE EXTENDED IS CHARACTERIZED BY UNCERTAINTY AS ONE WOULD
EXPECT IN THE DAY 6 -7 TIME FRAME.  ECMWF HAS A STRONGER SYSTEM
CROSSING FRIDAY NIGHT VERSUS GFS WHICH IS MUCH WEAKER.  EITHER CASE
PTYPE SHOULD BE RAIN WITH SNOW SHOWERS ON THE BACKSIDE.  NO PLUNGES
OF ARCTIC AIR ARE FORECAST IN THE NEXT 10 DAYS.  MAX/MIN
TEMPERATURES WERE A BLEND OF THE FORECAST AND ECMWF BIAS CORRECTED
DATA SET.

&&

.AVIATION /23Z SATURDAY THROUGH THURSDAY/...
WHILE FKL...DUJ...AND ZZV ARE EXPECTED TO REMAIN UNDER MVFR CIGS
OVERNIGHT...REMAINING TERMINALS MAY CONTINUE TO HAVE LOWER CLOUDS
SCATTER OUT LEAVING A MID DECK TEMPORARILY. BY MIDNIGHT ALL
TERMINALS ARE EXPECTED TO RETURN TO UNIFORM MVFR CIGS. CANNOT RULE
OUT SOME CIGS BELOW 2KFT BUT DID NOT HAVE CONFIDENCE TO INCLUDE
THEM. UNCERTAINTY REMAINS AS TO WHEN SKIES SHOULD SCATTER OUT ON
SUNDAY. THE SCATTERING TREND SHOULD MOVE FROM SOUTHWEST TO
NORTHEAST...BUT CURRENT FORECAST DOES NOT ELIMINATE CIG FROM
PITTSBURGH AND LOCATIONS NORTHEAST UNTIL 00Z MONDAY.


OUTLOOK.../SUNDAY NIGHT THROUGH THURSDAY/...
NEXT STORM SYSTEM WILL BEGIN TO IMPACT THE REGION ON TUESDAY AND
RESULT IN WIDESPREAD RAIN...CIG/VIS RESTRICTIONS...AND PERIODS OF
LLWS INTO THURSDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$









000
FXUS61 KPBZ 202323
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
623 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE WILL BE IN CONTROL INTO MONDAY. EXPECT INCREASING
PRECIPITATION CHANCES TUESDAY. STORM SYSTEM BRINGS RAIN AND WIND
CHRISTMAS EVE...AND SNOW SHOWERS CHRISTMAS DAY.

&&

.NEAR TERM /THROUGH SUNDAY/...
WITH 615PM UPDATE...LOWER CLOUDS REMAIN SCATTERED OUT FROM
PITTSBURGH TO LATROBE AND MORGANTOWN...BUT DO NOT EXPECT THIS TO
PERSIST THROUGH THE EVENING. MINIMAL CHANGES WERE NEEDED TO HOURLY
TEMPERATURE TRENDS. PREVIOUS DISCUSSION FOLLOWS.

WEAKER INVERSION ACROSS PORTIONS OF SOUTHERN PA HAS ALLOWED LOWER
CLOUDS TO BREAK UP SOMEWHAT...ALTHOUGH THEY ARE HANGING TOUGH SO FAR
ACROSS THE NORTHERN COUNTIES NEAR FKL/DUJ AS WELL AS IN SOUTHEAST
OHIO.  EXPECT THESE TO REFORM TONIGHT AS INVERSION SHARPENS UP AGAIN
IN VERY WEAK FLOW...THUS GOING MOSTLY CLOUDY MOST AREAS.  GOING TO HANG
ON TO SLIGHT CHANCE POPS IN THE SOUTHEAST WITH SHORTWAVE TROUGH
MOVING ACROSS AND SLIGHTLY BETTER MOISTURE PROFILE...BUT SNOW
ACCUMULATION IS NOT EXPECTED.  THIS POSSIBILITY ENDS BY 09Z. ONLY
MINOR MODIFICATION TO GENERALLY SEASONABLE TEMPERATURES.

INVERSION IS MAINTAINED SUNDAY MORNING...BUT BY AFTERNOON EXPECT
STRATUS TO MIX OUT INTO A CU FIELD AND THEN SCATTER OUT BY EVENING.
A BIT MORE SUN SHOULD ALLOW FOR AFTERNOON HIGH TEMPS AROUND 5
DEGREES WARMER THAN TODAY. CL

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
BENIGN WEATHER INITIALLY WITH HIGH PRESSURE TO OUR EAST AND IN
CONTROL.  SOUTHEAST WINDS IN RESPONSE TO SURFACE ANTICYCLONE
POSITION WILL FACILITATE DEVELOPMENT OF STRATUS OVER EASTERN
PORTIONS OF TUCKER AND GARRETT COUNTIES MONDAY INTO MONDAY NIGHT.
PCPN ONSET HAS SLOWED DOWN FROM PREVIOUS CYCLES...BUT THERE REMAINS
A VERY LOW PROBABILITY OF FREEZING RAIN AND/OR SLEET OVER
AFOREMENTIONED AREAS MONDAY.  FOR NOW...TRENDED FORECAST WITH PCPN
COMMENCING DURING THE AFTERNOON WHICH REFLECT LATEST NUMERICAL
MODELS.  WITH THIS SCENARIO...LOW LEVEL SUB-FREEZING AIR SHOULD
SCOUR OUT YIELDING AN ALL RAIN PTYPE.

RAIN SHADOW EFFECT TAKES PLACES TUESDAY WITH SOUTHEAST WINDS
WIDESPREAD OVER THE REGION. AN ISOLATED SHOWER REACHING EASTERN OHIO
AND FAR NWRN PA IS NOT OUT OF THE QUESTION...SO KEPT A SLIGHT
CHANCE.  WOULD NOT BE SURPRISED TO SEE BREAKS IN THE CLOUDS WHICH
COULD ALLOW FOR A FEW LOCATIONS TO EXCEED 60 DEGREES.  RECORD HIGHS
FOR PITTSBURGH...MORGANTOWN...AND ZANESVILLE ALL RESIDE WELL INTO
THE UPPER 60S...SO AT THIS JUNCTURE RECORD WARMTH IS NOT FORESEEN.
PRECIP ASSOCIATED WITH THE SURFACE LOW PRESSURE SYSTEM EJECTING FROM
THE GULF COAST REGION REACHES SERN AREAS OF THE FORECAST AREA THAT
EVENING.

A BLEND OF THE ONGOING FORECAST AND BIAS CORRECTED ECMWF WERE USED
FOR TEMPERATURES.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
HIGHLIGHTS:
- A WET CHRISTMAS EVE
- TEMPERATURES RETURN BACK TO NORMAL VALUES CHRISTMAS DAY
- SLIGHTLY ABOVE NORMAL TEMPERATURES RETURN BY FRIDAY

STRONG LOW PRESSURE SYSTEM THAT HAS BEEN MUCH ADVERTISED GIVEN THE
TIME PERIOD WHICH IT AFFECTS OUR AREA IS STILL ON TRACK.  LONG RANGE
ENSEMBLE PREDICTION SYSTEMS AND OPERATIONAL MODELS ARE CONVERGING ON
A TRACK THROUGH IND / ILL THEN NORTH INTO CANADA.  THIS WILL MAKE
FOR ALL LIQUID PRECIPITATION ON THE FRONT END.  TEMPERATURES WILL
SOAR TO NEARLY 20 DEGREES ABOVE NORMAL WEDNESDAY WITH 50S COMMON.
COUPLED WITH INFLUX OF MOISTURE FROM THE GULF OF MEXICO...SOUNDINGS
ILLUSTRATE ELEVATED INSTABILITY WHICH PUSHES TEMP DIFFERENTIAL
BETWEEN H8 AND H5 TO NEARLY 0C.  THIS COULD LEAD TO ISOLATED
THUNDERSTORMS AHEAD OF THE BAROCLINIC ZONE.  FOR THE TIME
BEING...OPTED TO LEAVE THUNDER OUT OF THE FORECAST AND WAIT FOR
BETTER CONTINUITY GIVEN THIS STILL IS FIVE DAYS OUT.  DESPITE PWATS
NEARLY TWO STANDARD DEVIATIONS ABOVE NORMAL...COMBINATION OF
KATABATIC WINDS AND DRY CONVEYOR BELT WILL LIMIT QPF POTENTIAL TO
NEGATE ANY FLOOD THREAT.  LONG RANGE HYDROLOGIC MODELS SHOW VERY
LITTLE RISE IN AREA RIVERS...WHICH CORRELATES WELL TO THE PROJECTED
QPF OF 0.50 TO 1.00".

WITH THE TRACK OF THE CYCLONE DUE N...COLD AIR INJECTED INTO THE
AREA WILL BE OF MIDWEST ORIGIN...SO TEMPS WILL RETREAT BACK TO
SEASONAL BENCHMARKS CHRISTMAS DAY.  FOR THOSE WHO ARE LOOKING FOR
SNOW ON CHRISTMAS...A CHANCE OF SNOW SHOWERS EXIST...BUT GIVEN
TRAJECTORY FROM THE SOUTHWEST ANY ACCUMULATION ASSOCIATED WITH THE
UPPER LEVEL SYSTEM WILL BE LIGHT AT BEST.  HISTORICALLY...THERE IS
ONLY A 17 PERCENT CHANCE OF AT LEAST ONE INCH OF SNOW ON THE GROUND
AT PITTSBURGH CHRISTMAS MORNING.

H8 WINDS PUSH 50KTS WEDNESDAY NIGHT INTO THURSDAY AND HIGHEST
ANOMALIES RESIDE ALONG THE LAKE SHORE...SO EXPECT HIGHEST GUSTS
WOULD DO SO AS WELL.  NONETHELESS...PERIOD FROM WEDNESDAY NIGHT INTO
THURSDAY STRONG ISALLOBARIC FLOW COULD YIELD GUSTS IN EXCESS OF 40
MPH ESPECIALLY IN THE MOUNTAINS OF WRN MD AND NRN WV.

BALANCE OF THE EXTENDED IS CHARACTERIZED BY UNCERTAINTY AS ONE WOULD
EXPECT IN THE DAY 6 -7 TIME FRAME.  ECMWF HAS A STRONGER SYSTEM
CROSSING FRIDAY NIGHT VERSUS GFS WHICH IS MUCH WEAKER.  EITHER CASE
PTYPE SHOULD BE RAIN WITH SNOW SHOWERS ON THE BACKSIDE.  NO PLUNGES
OF ARCTIC AIR ARE FORECAST IN THE NEXT 10 DAYS.  MAX/MIN
TEMPERATURES WERE A BLEND OF THE FORECAST AND ECMWF BIAS CORRECTED
DATA SET.

&&

.AVIATION /23Z SATURDAY THROUGH THURSDAY/...
WHILE FKL...DUJ...AND ZZV ARE EXPECTED TO REMAIN UNDER MVFR CIGS
OVERNIGHT...REMAINING TERMINALS MAY CONTINUE TO HAVE LOWER CLOUDS
SCATTER OUT LEAVING A MID DECK TEMPORARILY. BY MIDNIGHT ALL
TERMINALS ARE EXPECTED TO RETURN TO UNIFORM MVFR CIGS. CANNOT RULE
OUT SOME CIGS BELOW 2KFT BUT DID NOT HAVE CONFIDENCE TO INCLUDE
THEM. UNCERTAINTY REMAINS AS TO WHEN SKIES SHOULD SCATTER OUT ON
SUNDAY. THE SCATTERING TREND SHOULD MOVE FROM SOUTHWEST TO
NORTHEAST...BUT CURRENT FORECAST DOES NOT ELIMINATE CIG FROM
PITTSBURGH AND LOCATIONS NORTHEAST UNTIL 00Z MONDAY.


OUTLOOK.../SUNDAY NIGHT THROUGH THURSDAY/...
NEXT STORM SYSTEM WILL BEGIN TO IMPACT THE REGION ON TUESDAY AND
RESULT IN WIDESPREAD RAIN...CIG/VIS RESTRICTIONS...AND PERIODS OF
LLWS INTO THURSDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$








000
FXUS61 KPHI 202125
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
425 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE WILL SLOWLY BUILD SOUTHWESTWARD INTO THE
REGION FROM ATLANTIC CANADA THROUGH MONDAY. LOW PRESSURE
WILL ORGANIZE OFF THE CAROLINAS MONDAY NIGHT AND MOVE
NORTHEASTWARD OFFSHORE ON TUESDAY. MEANWHILE...ANOTHER
AREA OF LOW PRESSURE WILL DEVELOP OVER THE OHIO VALLEY
AND MOVE NORTHWARD INTO QUEBEC...LEADING TO A STRONG
COLD FRONTAL PASSAGE ON THURSDAY NIGHT. HIGH PRESSURE
WILL BUILD IN ON FRIDAY AND A WEAKER COLD FRONT MAY
APPROACH THE REGION NEXT WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WEAK HIGH PRESSURE WILL REMAIN ACROSS THE AREA TONIGHT. THERE IS
PLENTY OF MOISTURE TRAPPED BELOW THE INVERSION WHICH IS AROUND 4K-5K
FT ALOFT. THE CLOUDS ARE BREAKING UP SOMEWHAT JUST TO THE WEST AS OF
MID-AFTERNOON...SO SOME BREAKS CAN BE EXPECTED THIS EVENING...MOSTLY
ACROSS THE DELMARVA AND SRN NJ. ANOTHER SEASONABLY COLD NIGHT
EXPECTED WITH LOWS IN THE LOW 20S NORTH AND MID OR UPPER 20S SOUTH.
WINDS WILL BE LIGHT FROM THE NORTH.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
AFTER A WEAK SHORTWAVE CROSSES THE AREA SUN MORNING...UPPER RIDGING
WILL TAKE PLACE. THIS WILL HOPEFULLY ALLOW MORE SUNSHINE ACROSS THE
AREA. WE HAVE WRITTEN A PARTLY TO MOSTLY SUNNY FCST FOR NOW. WE HELD
ONTO SOME EXTRA CLOUD COVER ACROSS THE SRN POCONOS HOWEVER. HIGH
TEMPERATURES SUNDAY WILL RISE INTO THE LOW 40S ACROSS SRN NJ AND THE
DELMARVA...WHILE READINGS HOLD IN THE MID/UPPER 30S ACROSS THE
NORTH/WEST AREAS. WINDS WILL REMAIN LIGHT...MOSTLY FROM THE NORTH.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
HIGHLIGHTS...

* FREEZING RAIN POSSIBLE MONDAY NIGHT OVER THE NORTHWEST.
* INCREASING POTENTIAL FOR HEAVY RAIN CHRISTMAS EVE WITH
  TEMPERATURES WELL ABOVE NORMAL.
* BRISK WESTERLY WIND CHRISTMAS DAY W/FLURRIES POSSIBLE.

OVERVIEW...

VIGOROUS MID-LEVEL DISTURBANCE AND ACCOMPANYING 160 KNOT UPPER-LEVEL
JET MAX COMING ASHORE OVER THE PACIFIC NORTHWEST LATE THIS WEEKEND
WILL LEAD TO A DEEP TROUGH OVER THE MISSISSIPPI VALLEY BY MID-WEEK.
INITIAL PIECE OF ENERGY AHEAD OF THIS TROUGH IS EJECTED NORTHEAST
AND WILL LEAD TO THE DEVELOPMENT OF AN AREA OF LOW-PRESSURE OFF THE
CAROLINAS ON MONDAY. THIS WEAK FEATURE SHOULD TRACK OFFSHORE WELL
SOUTHEAST OF THE REGION ON TUESDAY PER TODAYS 12Z UKMET AND GFS...
FEEL THE NAM AND ECMWF ARE TOO FAR NORTH, SLOW, AND DEEP W/THIS
FEATURE...THUS THEY ALSO CRANK OUT TOO MUCH QPF. NEVERTHELESS...
QPF COMBINED WITH MARGINAL TEMPERATURE PROFILES OVER THE NORTHWEST
COULD SUPPORT SOME LIGHT FREEZING RAIN MONDAY NIGHT. MID-LEVEL FLOW
THEN BECOMES INCREASINGLY MERIDIONAL...PUMPING ANOMALOUSLY WARM
AND MOIST AIR UP THE EAST COAST...SETTING THE STAGE FOR HEAVY RAIN
ON CHRISTMAS EVE DAY. THE TROUGH LOOKS TO BECOME NEGATIVELY TILTED
AS IT CROSSES THE REGION...LEADING TO A STRONG FRONTAL PASSAGE LATE
WEDNESDAY INTO EARLY THURSDAY...WITH SOME FLURRIES POSSIBLE ON THE
BACK-SIDE OF THE STORM SYSTEM.

DETAILS...

MONDAY...
MID-LEVEL RIDGE CRESTS OVER THE REGION EARLY IN THE DAY...W/SURFACE
HIGH ANCHORED ALONG THE EAST COAST IN A COLD-AIR DAMMING SIGNATURE.
PRECIPITATION WILL BE LARGELY DRIVEN BY INSENTROPIC ASCENT OVER THE
COLDER LOW-LEVEL AIRMASS AND WILL BEGIN LATE IN THE DAY AS MOISTURE
STREAMS IN ALOFT AND LOW-LEVELS GRADUALLY SATURATE. THERE MAY BE A
PERIOD OF LIGHT FREEZING RAIN OVER THE NORTHWEST AS A COLD AIR
IS REINFORCED W/NORTHERLY SURFACE WINDS AND PRECIP LEADS TO
EVAPORATIONAL COOLING.

TUESDAY...
ANY LIGHT FREEZING RAIN SHOULD END EARLY IN THE MORNING WITH STRONG
WARM AIR ADVECTION ALOFT. ALTHOUGH THE BEST FORCING REMAINS WELL TO
THE WEST...BROAD ISENTROPIC ASCENT AND INCREASING MOISTURE SHOULD
LEAD TO SCATTERED RAIN SHOWERS THRU THE DAY. QPF SHOULD BE GENERALLY
LIGHT.

WEDNESDAY...
A VIGOROUS TROUGH APPROACHES FROM THE WEST W/STILL SOME SPREAD NOTED
FROM THE MEAN IN BOTH THE ECENS AND GEFS 500 HPA HEIGHT FIELDS...
INDICATING SOME DISAGREEMENT WITH REGARD TO WHAT DEGREE IT GOES
NEGATIVELY TILTED. NEVERTHELESS...A VERY DYNAMIC SYSTEM WITH SEVERAL
INGREDIENTS COMING TOGETHER FOR UP TO 1-2 INCHES OF QPF...ESPECIALLY
OVER THE HIGHER TERRAIN. NOTING A STRONG MID-LEVEL VORT MAX AND THE
LEFT-FRONT QUADRANT OF A 160 KNOT UPPER-LEVEL JET TRAVERSING THE
APPALACHIANS. ALSO NOTING STRONG WARM AIR ADVECTION AND ANOMALOUSLY
HIGH /2-3 STANDARD DEVIATION/ PRECIPITABLE WATER VALUES STREAMING
UP THE EASTERN SEABOARD. THUS THERE IS PLENTY OF MOISTURE AND
ASCENT FOR HEAVY RAINFALL...W/THE MODELS KEYING IN ON WEDNESDAY
AFTERNOON AND WEDNESDAY NIGHT FOR THE BULK OF THE PRECIP...AND
THIS WILL NEED TO BE MONITORED FOR FLOODING POTENTIAL PARTICULARLY
DUE TO THE HOLIDAY TRAVEL CHRISTMAS EVE. LATER SHIFTS WILL ALSO
NEED TO FURTHER EVALUATE THE POTENTIAL FOR GUSTY SURFACE WINDS
AND CONVECTION.

THURSDAY AND FRIDAY...
LOW-PRESSURE MOVES NORTHWARD INTO QUEBEC AND HIGH-PRESSURE BEGINS TO
BUILD IN. TEMPERATURES WILL REMAIN ABOVE SEASONABLE LEVELS AND THERE
COULD BE SNOW SHOWERS IN THE BLUSTERY NORTHWEST FLOW ON THURSDAY...
PARTICULARLY NORTHWEST.

SATURDAY...ANOTHER COLD FRONT MAY APPROACH THE REGION...BUT IT/S TOO
EARLY TO SPECULATE...ESPECIALLY GIVEN THE UNCERTAINTY THAT THE STORM
SYSTEM MOVING THROUGH THE NORTHEAST CONUS MID-WEEK COULD ADD TO THE
FORECAST.

&&

.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

THERE HAS BEEN PLENTY OF LOW LEVEL MOISTURE TRAPPED BELOW THE
INVERSION AGAIN TODAY. CIGS HAVE BEEN MOSTLY 025-035 ACROSS THE
AREA. WINDS HAVE BEEN LIGHT...MOSTLY IN THE NORTH QUADRANT.
CONDITIONS WILL NOT CHANGE MUCH THIS AFTERNOON...BUT SATELLITE PICS
DO SHOW SOME BREAKS IN THE DECK ACROSS NRN MD AND THE SUSQ VALLEY
WHICH MAY ARRIVE ACROSS THE DEL VALLEY AROUND EVENING. MUCH OF THE
GUIDANCE INDICATES MORE CLEARING (OF THE LOW CLOUDS) OVERNIGHT WITH
SOME CI/CS ABOVE. WE HAVE GONE ALONG WITH THAT FOR THE TAFS...BUT A
FEW SITES HOLDING ON TO LOW CLOUDS LONGER...WOULDN`T SURPRISE ME.
SUNDAY...VFR EXPECTED WITH JUST SOME FEW-SCT LOW CLOUDS AND MOSTLY N
OR NE WINDS.

OUTLOOK...

SUNDAY NIGHT AND MONDAY MORNING...VFR.

MONDAY AFTERNOON...POTENTIAL FOR MVFR CIGS AS MARINE LAYER BECOMES
ESTABLISHED AND STRATUS ADVECTS INLAND.

MONDAY NIGHT THROUGH TUESDAY NIGHT...THE COMBINATION OF
STRENGTHENING ONSHORE FLOW AND IN-SITU CAD FROM LIGHT RAIN
OVERSPREADING THE TERMINALS COULD YIELD AN EXTENDED PERIOD OF
MVFR/IFR CONDITIONS (CIGS WOULD BE THE MORE LIKELY CONTRIBUTOR TO
IFR THAN VSBYS) MONDAY NIGHT INTO TUESDAY.

WEDNESDAY...WINDS VEER MORE OUT OF THE SOUTH AS A WARM FRONT SLOWLY
LIFTS NORTHWARD. RAIN IS EXPECTED TO BE THE MOST WIDESPREAD AND
HEAVIEST DURING THIS PART OF THE FORECAST PERIOD. PREDOMINATELY MVFR
AND IFR CONDITIONS. SOUTHERLY WINDS WILL BECOME BREEZY FOLLOWING
WARM FROPA.

WEDNESDAY NIGHT...COLD FRONT IS FORECAST TO MOVE THRU SOMETIME AT
NIGHT. LOW CLOUDS AND RAIN WILL END FROM WEST TO EAST IN WAKE OF
FROPA.

THURSDAY...WESTERLY WINDS COULD BECOME STRONG BEHIND THE FRONT
THURSDAY WITH BUFKIT FORECAST SOUNDINGS FROM THE 12Z GFS SHOWING THE
POTENTIAL FOR 30-40 KT GUSTS.

&&

.MARINE...
WEAK HIGH PRESSURE WILL REMAIN ACROSS THE WATERS TONIGHT AND SUNDAY.
WINDS AND SEAS WILL REMAIN BELOW SCA FLAG CRITERIA. WINDS WILL
MOSTLY BE NORTHERLY THROUGH THE PERIOD.

OUTLOOK...
SUNDAY NIGHT THROUGH MONDAY NIGHT...WINDS AND SEAS BELOW SCA
CRITERIA.

TUESDAY AND TUESDAY NIGHT...ONSHORE FLOW STRENGTHENS ON TUESDAY.
WINDS 15-20 KT FORECAST ON TUESDAY. SEAS ARE FORECAST TO BUILD TO
5-6 FEET TUESDAY AND TUESDAY NIGHT, WARRANTING THE NEED FOR A SCA.

WEDNESDAY AND WEDNESDAY NIGHT...SOUTHERLY WINDS STRENGTHEN AFTER
WARM FROPA. DESPITE WINDS OF 40-50 KT FORECAST 1000 FT ABOVE THE
SURFACE, THERMAL PROFILES NOT FAVORABLE FOR MIXING WITH THE SETUP OF
WARM AIR MOVING ATOP THE COOLER WATERS. EXPECTING MORE OF A HIGH END
SCA WITH 25-30 KT WINDS. WINDS FORECAST TO BECOME WESTERLY LATE
WEDNESDAY NIGHT BEHIND A COLD FRONT BUT THE CORE OF THE COLD AIR
WILL STILL REMAIN UPSTREAM OF THE WATERS. SEAS FORECAST TO INCREASE
TO 6-8 FEET.

THURSDAY...GUSTY WESTERLY WINDS EXPECTED. GALES CERTAINLY A
POSSIBILITY.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANCK
NEAR TERM...O`HARA
SHORT TERM...O`HARA
LONG TERM...FRANCK
AVIATION...KLEIN/O`HARA
MARINE...KLEIN/O`HARA






000
FXUS61 KPHI 202125
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
425 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE WILL SLOWLY BUILD SOUTHWESTWARD INTO THE
REGION FROM ATLANTIC CANADA THROUGH MONDAY. LOW PRESSURE
WILL ORGANIZE OFF THE CAROLINAS MONDAY NIGHT AND MOVE
NORTHEASTWARD OFFSHORE ON TUESDAY. MEANWHILE...ANOTHER
AREA OF LOW PRESSURE WILL DEVELOP OVER THE OHIO VALLEY
AND MOVE NORTHWARD INTO QUEBEC...LEADING TO A STRONG
COLD FRONTAL PASSAGE ON THURSDAY NIGHT. HIGH PRESSURE
WILL BUILD IN ON FRIDAY AND A WEAKER COLD FRONT MAY
APPROACH THE REGION NEXT WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WEAK HIGH PRESSURE WILL REMAIN ACROSS THE AREA TONIGHT. THERE IS
PLENTY OF MOISTURE TRAPPED BELOW THE INVERSION WHICH IS AROUND 4K-5K
FT ALOFT. THE CLOUDS ARE BREAKING UP SOMEWHAT JUST TO THE WEST AS OF
MID-AFTERNOON...SO SOME BREAKS CAN BE EXPECTED THIS EVENING...MOSTLY
ACROSS THE DELMARVA AND SRN NJ. ANOTHER SEASONABLY COLD NIGHT
EXPECTED WITH LOWS IN THE LOW 20S NORTH AND MID OR UPPER 20S SOUTH.
WINDS WILL BE LIGHT FROM THE NORTH.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
AFTER A WEAK SHORTWAVE CROSSES THE AREA SUN MORNING...UPPER RIDGING
WILL TAKE PLACE. THIS WILL HOPEFULLY ALLOW MORE SUNSHINE ACROSS THE
AREA. WE HAVE WRITTEN A PARTLY TO MOSTLY SUNNY FCST FOR NOW. WE HELD
ONTO SOME EXTRA CLOUD COVER ACROSS THE SRN POCONOS HOWEVER. HIGH
TEMPERATURES SUNDAY WILL RISE INTO THE LOW 40S ACROSS SRN NJ AND THE
DELMARVA...WHILE READINGS HOLD IN THE MID/UPPER 30S ACROSS THE
NORTH/WEST AREAS. WINDS WILL REMAIN LIGHT...MOSTLY FROM THE NORTH.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
HIGHLIGHTS...

* FREEZING RAIN POSSIBLE MONDAY NIGHT OVER THE NORTHWEST.
* INCREASING POTENTIAL FOR HEAVY RAIN CHRISTMAS EVE WITH
  TEMPERATURES WELL ABOVE NORMAL.
* BRISK WESTERLY WIND CHRISTMAS DAY W/FLURRIES POSSIBLE.

OVERVIEW...

VIGOROUS MID-LEVEL DISTURBANCE AND ACCOMPANYING 160 KNOT UPPER-LEVEL
JET MAX COMING ASHORE OVER THE PACIFIC NORTHWEST LATE THIS WEEKEND
WILL LEAD TO A DEEP TROUGH OVER THE MISSISSIPPI VALLEY BY MID-WEEK.
INITIAL PIECE OF ENERGY AHEAD OF THIS TROUGH IS EJECTED NORTHEAST
AND WILL LEAD TO THE DEVELOPMENT OF AN AREA OF LOW-PRESSURE OFF THE
CAROLINAS ON MONDAY. THIS WEAK FEATURE SHOULD TRACK OFFSHORE WELL
SOUTHEAST OF THE REGION ON TUESDAY PER TODAYS 12Z UKMET AND GFS...
FEEL THE NAM AND ECMWF ARE TOO FAR NORTH, SLOW, AND DEEP W/THIS
FEATURE...THUS THEY ALSO CRANK OUT TOO MUCH QPF. NEVERTHELESS...
QPF COMBINED WITH MARGINAL TEMPERATURE PROFILES OVER THE NORTHWEST
COULD SUPPORT SOME LIGHT FREEZING RAIN MONDAY NIGHT. MID-LEVEL FLOW
THEN BECOMES INCREASINGLY MERIDIONAL...PUMPING ANOMALOUSLY WARM
AND MOIST AIR UP THE EAST COAST...SETTING THE STAGE FOR HEAVY RAIN
ON CHRISTMAS EVE DAY. THE TROUGH LOOKS TO BECOME NEGATIVELY TILTED
AS IT CROSSES THE REGION...LEADING TO A STRONG FRONTAL PASSAGE LATE
WEDNESDAY INTO EARLY THURSDAY...WITH SOME FLURRIES POSSIBLE ON THE
BACK-SIDE OF THE STORM SYSTEM.

DETAILS...

MONDAY...
MID-LEVEL RIDGE CRESTS OVER THE REGION EARLY IN THE DAY...W/SURFACE
HIGH ANCHORED ALONG THE EAST COAST IN A COLD-AIR DAMMING SIGNATURE.
PRECIPITATION WILL BE LARGELY DRIVEN BY INSENTROPIC ASCENT OVER THE
COLDER LOW-LEVEL AIRMASS AND WILL BEGIN LATE IN THE DAY AS MOISTURE
STREAMS IN ALOFT AND LOW-LEVELS GRADUALLY SATURATE. THERE MAY BE A
PERIOD OF LIGHT FREEZING RAIN OVER THE NORTHWEST AS A COLD AIR
IS REINFORCED W/NORTHERLY SURFACE WINDS AND PRECIP LEADS TO
EVAPORATIONAL COOLING.

TUESDAY...
ANY LIGHT FREEZING RAIN SHOULD END EARLY IN THE MORNING WITH STRONG
WARM AIR ADVECTION ALOFT. ALTHOUGH THE BEST FORCING REMAINS WELL TO
THE WEST...BROAD ISENTROPIC ASCENT AND INCREASING MOISTURE SHOULD
LEAD TO SCATTERED RAIN SHOWERS THRU THE DAY. QPF SHOULD BE GENERALLY
LIGHT.

WEDNESDAY...
A VIGOROUS TROUGH APPROACHES FROM THE WEST W/STILL SOME SPREAD NOTED
FROM THE MEAN IN BOTH THE ECENS AND GEFS 500 HPA HEIGHT FIELDS...
INDICATING SOME DISAGREEMENT WITH REGARD TO WHAT DEGREE IT GOES
NEGATIVELY TILTED. NEVERTHELESS...A VERY DYNAMIC SYSTEM WITH SEVERAL
INGREDIENTS COMING TOGETHER FOR UP TO 1-2 INCHES OF QPF...ESPECIALLY
OVER THE HIGHER TERRAIN. NOTING A STRONG MID-LEVEL VORT MAX AND THE
LEFT-FRONT QUADRANT OF A 160 KNOT UPPER-LEVEL JET TRAVERSING THE
APPALACHIANS. ALSO NOTING STRONG WARM AIR ADVECTION AND ANOMALOUSLY
HIGH /2-3 STANDARD DEVIATION/ PRECIPITABLE WATER VALUES STREAMING
UP THE EASTERN SEABOARD. THUS THERE IS PLENTY OF MOISTURE AND
ASCENT FOR HEAVY RAINFALL...W/THE MODELS KEYING IN ON WEDNESDAY
AFTERNOON AND WEDNESDAY NIGHT FOR THE BULK OF THE PRECIP...AND
THIS WILL NEED TO BE MONITORED FOR FLOODING POTENTIAL PARTICULARLY
DUE TO THE HOLIDAY TRAVEL CHRISTMAS EVE. LATER SHIFTS WILL ALSO
NEED TO FURTHER EVALUATE THE POTENTIAL FOR GUSTY SURFACE WINDS
AND CONVECTION.

THURSDAY AND FRIDAY...
LOW-PRESSURE MOVES NORTHWARD INTO QUEBEC AND HIGH-PRESSURE BEGINS TO
BUILD IN. TEMPERATURES WILL REMAIN ABOVE SEASONABLE LEVELS AND THERE
COULD BE SNOW SHOWERS IN THE BLUSTERY NORTHWEST FLOW ON THURSDAY...
PARTICULARLY NORTHWEST.

SATURDAY...ANOTHER COLD FRONT MAY APPROACH THE REGION...BUT IT/S TOO
EARLY TO SPECULATE...ESPECIALLY GIVEN THE UNCERTAINTY THAT THE STORM
SYSTEM MOVING THROUGH THE NORTHEAST CONUS MID-WEEK COULD ADD TO THE
FORECAST.

&&

.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

THERE HAS BEEN PLENTY OF LOW LEVEL MOISTURE TRAPPED BELOW THE
INVERSION AGAIN TODAY. CIGS HAVE BEEN MOSTLY 025-035 ACROSS THE
AREA. WINDS HAVE BEEN LIGHT...MOSTLY IN THE NORTH QUADRANT.
CONDITIONS WILL NOT CHANGE MUCH THIS AFTERNOON...BUT SATELLITE PICS
DO SHOW SOME BREAKS IN THE DECK ACROSS NRN MD AND THE SUSQ VALLEY
WHICH MAY ARRIVE ACROSS THE DEL VALLEY AROUND EVENING. MUCH OF THE
GUIDANCE INDICATES MORE CLEARING (OF THE LOW CLOUDS) OVERNIGHT WITH
SOME CI/CS ABOVE. WE HAVE GONE ALONG WITH THAT FOR THE TAFS...BUT A
FEW SITES HOLDING ON TO LOW CLOUDS LONGER...WOULDN`T SURPRISE ME.
SUNDAY...VFR EXPECTED WITH JUST SOME FEW-SCT LOW CLOUDS AND MOSTLY N
OR NE WINDS.

OUTLOOK...

SUNDAY NIGHT AND MONDAY MORNING...VFR.

MONDAY AFTERNOON...POTENTIAL FOR MVFR CIGS AS MARINE LAYER BECOMES
ESTABLISHED AND STRATUS ADVECTS INLAND.

MONDAY NIGHT THROUGH TUESDAY NIGHT...THE COMBINATION OF
STRENGTHENING ONSHORE FLOW AND IN-SITU CAD FROM LIGHT RAIN
OVERSPREADING THE TERMINALS COULD YIELD AN EXTENDED PERIOD OF
MVFR/IFR CONDITIONS (CIGS WOULD BE THE MORE LIKELY CONTRIBUTOR TO
IFR THAN VSBYS) MONDAY NIGHT INTO TUESDAY.

WEDNESDAY...WINDS VEER MORE OUT OF THE SOUTH AS A WARM FRONT SLOWLY
LIFTS NORTHWARD. RAIN IS EXPECTED TO BE THE MOST WIDESPREAD AND
HEAVIEST DURING THIS PART OF THE FORECAST PERIOD. PREDOMINATELY MVFR
AND IFR CONDITIONS. SOUTHERLY WINDS WILL BECOME BREEZY FOLLOWING
WARM FROPA.

WEDNESDAY NIGHT...COLD FRONT IS FORECAST TO MOVE THRU SOMETIME AT
NIGHT. LOW CLOUDS AND RAIN WILL END FROM WEST TO EAST IN WAKE OF
FROPA.

THURSDAY...WESTERLY WINDS COULD BECOME STRONG BEHIND THE FRONT
THURSDAY WITH BUFKIT FORECAST SOUNDINGS FROM THE 12Z GFS SHOWING THE
POTENTIAL FOR 30-40 KT GUSTS.

&&

.MARINE...
WEAK HIGH PRESSURE WILL REMAIN ACROSS THE WATERS TONIGHT AND SUNDAY.
WINDS AND SEAS WILL REMAIN BELOW SCA FLAG CRITERIA. WINDS WILL
MOSTLY BE NORTHERLY THROUGH THE PERIOD.

OUTLOOK...
SUNDAY NIGHT THROUGH MONDAY NIGHT...WINDS AND SEAS BELOW SCA
CRITERIA.

TUESDAY AND TUESDAY NIGHT...ONSHORE FLOW STRENGTHENS ON TUESDAY.
WINDS 15-20 KT FORECAST ON TUESDAY. SEAS ARE FORECAST TO BUILD TO
5-6 FEET TUESDAY AND TUESDAY NIGHT, WARRANTING THE NEED FOR A SCA.

WEDNESDAY AND WEDNESDAY NIGHT...SOUTHERLY WINDS STRENGTHEN AFTER
WARM FROPA. DESPITE WINDS OF 40-50 KT FORECAST 1000 FT ABOVE THE
SURFACE, THERMAL PROFILES NOT FAVORABLE FOR MIXING WITH THE SETUP OF
WARM AIR MOVING ATOP THE COOLER WATERS. EXPECTING MORE OF A HIGH END
SCA WITH 25-30 KT WINDS. WINDS FORECAST TO BECOME WESTERLY LATE
WEDNESDAY NIGHT BEHIND A COLD FRONT BUT THE CORE OF THE COLD AIR
WILL STILL REMAIN UPSTREAM OF THE WATERS. SEAS FORECAST TO INCREASE
TO 6-8 FEET.

THURSDAY...GUSTY WESTERLY WINDS EXPECTED. GALES CERTAINLY A
POSSIBILITY.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANCK
NEAR TERM...O`HARA
SHORT TERM...O`HARA
LONG TERM...FRANCK
AVIATION...KLEIN/O`HARA
MARINE...KLEIN/O`HARA







000
FXUS61 KCTP 201942
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
242 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE SLIDING EASTWARD THROUGH QUEBEC WITH A SECOND HIGH
PRESSURE CELL OVER THE EASTERN GREAT LAKES AND OHIO VALLEY WILL
KEEP MAINTAIN DRY WEATHER ACROSS CENTRAL PENNSYLVANIA FOR THE REST
OF THIS WEEKEND. AN AMPLIFYING UPPER RIDGE MOVING INTO THE REGION
WILL BRING INCREASING AMOUNTS OF SUNSHINE ON SUNDAY...BUT WILL BE
QUICKLY REPLACED BY A LARGE STORM SYSTEM TRACKING ACROSS THE
CENTRAL UNITED STATES. MOISTURE ASSOCIATED WITH THAT STORM AND
INCREASING EAST FLOW OFF OF THE WESTERN ATLANTIC WILL BRING
INCREASING CLOUDS ON MONDAY...WITH QUITE MILD BUT UNSETTLED
CONDITIONS PREVAILING THROUGH MID WEEK. A VIGOROUS STORM SYSTEM
WILL SWEEP ACROSS THE COMMONWEALTH ON CHRISTMAS EVE BRINGING
WIDESPREAD SHOWERS AND A CHANCE FOR THUNDERSTORMS...FOLLOWED BY
WINDY AND COLDER CONDITIONS WITH SCATTERED SNOW SHOWERS AND
FLURRIES ACROSS THE WEST AND NORTH FOR CHRISTMAS DAY. MILDER
CONDITIONS WILL ARRIVE ONCE AGAIN BY LATE THIS WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
SUBSIDENCE AND DOWNSLOPING OVER MUCH OF THE LAUREL HIGHLANDS AND
PARTS OF THE CENTRAL AND SOUTH CENTRAL MOUNTAINS IS BRINGING SOME
MUCH NEEDED SUNSHINE TO THOSE AREAS. VISIBLE IMAGERY INDICATES THE
NORTHWARD EXTENT PUSHING TOWARDS CENTRAL CLEARFIELD COUNTY AND
SOUTHERN CENTRE COUNTY...AND IT APPEARS LIKELY TO REACH A LITTLE
FARTHER NORTH BEFORE SUNSET.

EXPECT CLOUDS TO FILL BACK IN OVERNIGHT...AS 5H WAVE TRACKS ACROSS
THE OHIO VALLEY AND INTO SOUTHWEST PA BY 12Z SUN. MINS WILL BE
FAIRLY UNIFORM AND RANGE FROM THE LOWER 20S NORTH TO THE UPPER 20S
SOUTHEAST.

&&

.SHORT TERM /SUNDAY/...
DEEP LAYER DRYING BEHIND THE AFOREMENTIONED DEPARTING 5H WAVE AND
UPPER LEVEL RIDGING HAS THE POTENTIAL TO BRING SUNSHINE TO MOST IF
NOT ALL OF CENTRAL PA ON MONDAY. THE STUBBORN STRATUS THAT HAS
PLAGUED US FOR MORE THAN A WEEK WILL HAVE A CHANCE TO MIX
OUT...BUT TRANSITORY SFC HIGH PRESSURE MAY STILL MAKE THIS A SLOW
PROCESS OVER THE NORTH.

PRIOR TO THAT...SOME AREAS COULD PERHAPS SEE A FLURRY IN THE PRE
DAWN HOURS SUNDAY BEFORE THE WAVE QUICKLY EXITS EASTWARD. WENT
CLOSE TO CONSALL GUIDANCE AGAIN WITH MAXES REACHING THE MID TO
UPPER 30S NORTH TO THE LOWER 40S SOUTH.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...

THE MOST SIGNIFICANT FORECAST ISSUE IN THE LONG TERM IS THE
EVOLUTION OF THE MASSIVE CYCLONE TO OUR WEST 23-25 DECEMBER.
STRONG SOUTHERLY FLOW AHEAD OF THIS SYSTEM WILL BRING WARM AIR
INTO THE REGION LATE MONDAY INTO TUESDAY. BY TUESDAY AND WEDNESDAY
MANY LOW- LEVEL TEMPERATURE AND MOISTURE FIELDS WILL BE WELL ABOVE
THEIR SEASONAL VALUES. THIS IMPLIES VERY WARM WEATHER TUESDAY AND
WEDNESDAY...WHEN THE SHALLOW COLD AIR SCOURS OUT EAST OF THE
MOUNTAINS.

A COLD FRONT WITH STRONG WINDS WILL PRODUCE COLDER
CONDITIONS...LIKELY LATE CHRISTMAS EVE INTO CHRISTMAS DAY. THERE
WILL BE STRONG WESTERLY WINDS AND STRONG WIND GUSTS. SNOW SHOWERS
ARE LIKELY BEHIND THE SYSTEM IN WESTERN AREAS.

THE CHANGEABLE DETAILS...MONDAY THE ENSEMBLE FORECAST SHOWS A
WAVE PASSING TO OUR SOUTH WHICH COULD PRODUCE LIGHT SNOW OR A
MIX...MAINLY IN SOUTHEASTERN AREAS. THE IMPLIED LOW-LEVEL BOUNDARY
IS THE RETREATING COLD AIR TO OUR NORTHEAST AS THE STRONG CYCLONE
TO OUR WEST BEGINS TO TAKE SHAPE. IMPLIED LOW-LEVEL AGEOSTROPHIC
NORTHERLY FLOW HOLDING LOW-LEVEL COLD AIR IN MONDAY INTO TUESDAY.

TUESDAY THE COLD AIR SHOULD CONTINUE TO ERODE. HAD TO KEEP SOME
FREEZE RAIN/DRIZZLE IN NORTHEASTERN AREAS OVERNIGHT MONDAY INTO
TUESDAY BASED ON IMPLIED AGEOSTROPHIC FLOW AND ENSEMBLE
PRECIPITATION TYPES. BUT DURING THE DAY TUESDAY THE WARM AIR
SHOULD WIN OUT. THOUGH ALL SYSTEMS SHOW SOME HINTS OF COLD AIR
DAMMING....DAYTIME HIGHS EAST/NORTHEAST AREAS WILL BE WELL BELOW
WHAT ONE MIGHT EXPECT WITH 6-10C 850 MB TEMPS.

ANY PRECIPITATION TUESDAY AND WEDNESDAY SHOULD BE RAIN MUCH AFTER
NOON TUESDAY IN THE NORTHEAST. PRECIPITATION ON TUESDAY SHOULD BE
LIGHT...ENSEMBLES SHOW PROBABILITIES IN THE 20-30 RANGE AND LIGHT
AMOUNTS. THE PATTERN...SHARP NORTH-SOUTH FRONT TO OUR
WEST...IMPLIES SOME ISOLATED SHOWERS BUT THE MAIN RAIN EVENT
SHOULD WITHIN 3-6 HOURS OF THE FRONT.

TUESDAY THE STRONG CYCLONE...WITH SOME OF THE LOWEST SURFACE
PRESSURES IN THE EASTERN US ON 24 DECEMBER IN THE PAST 30 YEARS
WILL MOVE INTO THE GREAT LAKES. PRESSURE ANOMALIES ARE -3 TO -4
SIGMA BELOW NORMAL WITH A RETURN PERIOD ON THE ORDER OF 30 YEARS
IN SOME FORECAST SYSTEMS.

THE FRONT ASSOCIATED WITH THE CYCLONE PUSHES INTO OUR REGION
WEDNESDAY...AT THIS TIME THE 850 MB SOUTHERLY WINDS ARE FORECAST
TO BE ABOUT +3 SIGMA ABOVE NORMAL. THE STRONG SOUTHERLY FLOW...THE
HIGH PRECIPITABLE WATER...THE STRONG FRONT ALL IMPLY A FRONTAL
RAIN EVENT AND PERHAPS SOME RARE LATE DECEMBER (ELEVATED)
CONVECTION. IF THIS WERE AUTUMN OR SPRING WE MIGHT BE THINKING
QLCS. BUT SURFACE CAPE IS VIRTUALLY NON-EXISTENT BUT SHOWERY RAIN
AND PERHAPS ISOLATED THUNDER POSSIBLE.

DO NOT LIKE HAVING POPS ABOVE 60 TO 66 PERCENT AT DAY 5 IN 12 HOUR
PERIODS. TIMING WILL CLEARLY CHANGE BUT HAVE HIGH POPS FOR
CONSISTENCY WITH OTHER OFFICES.

CHRISTMAS EVE AND EARLY CHRISTMAS IS THE AREA OF HIGH UNCERTAINTY
AS TO WHEN THE COLD AIR COMES IN. THIS WILL DICTATE WHEN THE RAIN
COMES AND WHEN THE GUSTY WINDS SET IN. GRADIENTS ARE WHERE
FORECASTS ARE THEIR POOREST. BUT BY CHRISTMAS MORNING MOST IF NOT
ALL OF THE REGION SHOULD BE BELOW 0C AT 850 AND THE STRONG
WESTERLY WINDS SHOULD BE MIXING DOWN BEHIND THE FRONTAL BOUNDARY.
WINDY OVERNIGHT CHRISTMAS EVE INTO CHRISTMAS DAY. ANY RESIDUAL
PRECIPITATION SHOULD BE SNOW/SNOW SHOWERS AND FLURRIES.

TEMPERATURES SHOULD REBOUND FRIDAY AHEAD OF ANOTHER NORTHERN STREAM
WAVE MOVING INTO THE MID-WEST. THIS SHOULD RAISE OUR HEIGHTS AND
TEMPERATURES FRIDAY INTO EARLY SATURDAY. IT APPEARS A SERIES OF
WAVES MAY EVENTUALLY CARVE OUT A TROUGH OVER THE EAST-CENTRAL US. IF
SO...WE COULD END DECEMBER A BIT ON THE CHILLY SIDE.

&&

.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
SHALLOW STRATOCU DECK REMAINS TRAPPED BENEATH SUBSIDENCE
INVERSION THIS MORNING...WITH MVFR CIGS.  LOWER CIGS WILL PERSIST
IN THE NORTHERN MTNS...WITH IMPROVING CIGS CENTRAL AND SOUTH. WINDS
WILL BE LIGHT FROM THE WEST.

CIG RESTRICTIONS IN EXPANDING STRATOCU DECK LIKELY RETURN AGAIN
TONIGHT...THOUGH LOW CLOUDS SHOULD NOT BE QUITE AS EXPANSIVE AS
PREVIOUS NIGHTS. A SHORTWAVE WILL TRACK ACROSS THE REGION BRINGING
A THICKENING MID-LVL DECK AS WELL. SURFACE WINDS WILL CONTINUE TO
BE LIGHT...WITH SW FLOW ALOFT BEGINNING TO INCREASE AS A LARGE LOW
PRESSURE SYSTEM BEGINS TO DEEPEN OVER THE CENTRAL U.S.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

THU...WINDY AND COLDER WITH SCT MVFR CIGS AND -SHSN.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...DEVOIR/FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...GRUMM
AVIATION...DEVOIR/RXR



000
FXUS61 KCTP 201942
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
242 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE SLIDING EASTWARD THROUGH QUEBEC WITH A SECOND HIGH
PRESSURE CELL OVER THE EASTERN GREAT LAKES AND OHIO VALLEY WILL
KEEP MAINTAIN DRY WEATHER ACROSS CENTRAL PENNSYLVANIA FOR THE REST
OF THIS WEEKEND. AN AMPLIFYING UPPER RIDGE MOVING INTO THE REGION
WILL BRING INCREASING AMOUNTS OF SUNSHINE ON SUNDAY...BUT WILL BE
QUICKLY REPLACED BY A LARGE STORM SYSTEM TRACKING ACROSS THE
CENTRAL UNITED STATES. MOISTURE ASSOCIATED WITH THAT STORM AND
INCREASING EAST FLOW OFF OF THE WESTERN ATLANTIC WILL BRING
INCREASING CLOUDS ON MONDAY...WITH QUITE MILD BUT UNSETTLED
CONDITIONS PREVAILING THROUGH MID WEEK. A VIGOROUS STORM SYSTEM
WILL SWEEP ACROSS THE COMMONWEALTH ON CHRISTMAS EVE BRINGING
WIDESPREAD SHOWERS AND A CHANCE FOR THUNDERSTORMS...FOLLOWED BY
WINDY AND COLDER CONDITIONS WITH SCATTERED SNOW SHOWERS AND
FLURRIES ACROSS THE WEST AND NORTH FOR CHRISTMAS DAY. MILDER
CONDITIONS WILL ARRIVE ONCE AGAIN BY LATE THIS WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
SUBSIDENCE AND DOWNSLOPING OVER MUCH OF THE LAUREL HIGHLANDS AND
PARTS OF THE CENTRAL AND SOUTH CENTRAL MOUNTAINS IS BRINGING SOME
MUCH NEEDED SUNSHINE TO THOSE AREAS. VISIBLE IMAGERY INDICATES THE
NORTHWARD EXTENT PUSHING TOWARDS CENTRAL CLEARFIELD COUNTY AND
SOUTHERN CENTRE COUNTY...AND IT APPEARS LIKELY TO REACH A LITTLE
FARTHER NORTH BEFORE SUNSET.

EXPECT CLOUDS TO FILL BACK IN OVERNIGHT...AS 5H WAVE TRACKS ACROSS
THE OHIO VALLEY AND INTO SOUTHWEST PA BY 12Z SUN. MINS WILL BE
FAIRLY UNIFORM AND RANGE FROM THE LOWER 20S NORTH TO THE UPPER 20S
SOUTHEAST.

&&

.SHORT TERM /SUNDAY/...
DEEP LAYER DRYING BEHIND THE AFOREMENTIONED DEPARTING 5H WAVE AND
UPPER LEVEL RIDGING HAS THE POTENTIAL TO BRING SUNSHINE TO MOST IF
NOT ALL OF CENTRAL PA ON MONDAY. THE STUBBORN STRATUS THAT HAS
PLAGUED US FOR MORE THAN A WEEK WILL HAVE A CHANCE TO MIX
OUT...BUT TRANSITORY SFC HIGH PRESSURE MAY STILL MAKE THIS A SLOW
PROCESS OVER THE NORTH.

PRIOR TO THAT...SOME AREAS COULD PERHAPS SEE A FLURRY IN THE PRE
DAWN HOURS SUNDAY BEFORE THE WAVE QUICKLY EXITS EASTWARD. WENT
CLOSE TO CONSALL GUIDANCE AGAIN WITH MAXES REACHING THE MID TO
UPPER 30S NORTH TO THE LOWER 40S SOUTH.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...

THE MOST SIGNIFICANT FORECAST ISSUE IN THE LONG TERM IS THE
EVOLUTION OF THE MASSIVE CYCLONE TO OUR WEST 23-25 DECEMBER.
STRONG SOUTHERLY FLOW AHEAD OF THIS SYSTEM WILL BRING WARM AIR
INTO THE REGION LATE MONDAY INTO TUESDAY. BY TUESDAY AND WEDNESDAY
MANY LOW- LEVEL TEMPERATURE AND MOISTURE FIELDS WILL BE WELL ABOVE
THEIR SEASONAL VALUES. THIS IMPLIES VERY WARM WEATHER TUESDAY AND
WEDNESDAY...WHEN THE SHALLOW COLD AIR SCOURS OUT EAST OF THE
MOUNTAINS.

A COLD FRONT WITH STRONG WINDS WILL PRODUCE COLDER
CONDITIONS...LIKELY LATE CHRISTMAS EVE INTO CHRISTMAS DAY. THERE
WILL BE STRONG WESTERLY WINDS AND STRONG WIND GUSTS. SNOW SHOWERS
ARE LIKELY BEHIND THE SYSTEM IN WESTERN AREAS.

THE CHANGEABLE DETAILS...MONDAY THE ENSEMBLE FORECAST SHOWS A
WAVE PASSING TO OUR SOUTH WHICH COULD PRODUCE LIGHT SNOW OR A
MIX...MAINLY IN SOUTHEASTERN AREAS. THE IMPLIED LOW-LEVEL BOUNDARY
IS THE RETREATING COLD AIR TO OUR NORTHEAST AS THE STRONG CYCLONE
TO OUR WEST BEGINS TO TAKE SHAPE. IMPLIED LOW-LEVEL AGEOSTROPHIC
NORTHERLY FLOW HOLDING LOW-LEVEL COLD AIR IN MONDAY INTO TUESDAY.

TUESDAY THE COLD AIR SHOULD CONTINUE TO ERODE. HAD TO KEEP SOME
FREEZE RAIN/DRIZZLE IN NORTHEASTERN AREAS OVERNIGHT MONDAY INTO
TUESDAY BASED ON IMPLIED AGEOSTROPHIC FLOW AND ENSEMBLE
PRECIPITATION TYPES. BUT DURING THE DAY TUESDAY THE WARM AIR
SHOULD WIN OUT. THOUGH ALL SYSTEMS SHOW SOME HINTS OF COLD AIR
DAMMING....DAYTIME HIGHS EAST/NORTHEAST AREAS WILL BE WELL BELOW
WHAT ONE MIGHT EXPECT WITH 6-10C 850 MB TEMPS.

ANY PRECIPITATION TUESDAY AND WEDNESDAY SHOULD BE RAIN MUCH AFTER
NOON TUESDAY IN THE NORTHEAST. PRECIPITATION ON TUESDAY SHOULD BE
LIGHT...ENSEMBLES SHOW PROBABILITIES IN THE 20-30 RANGE AND LIGHT
AMOUNTS. THE PATTERN...SHARP NORTH-SOUTH FRONT TO OUR
WEST...IMPLIES SOME ISOLATED SHOWERS BUT THE MAIN RAIN EVENT
SHOULD WITHIN 3-6 HOURS OF THE FRONT.

TUESDAY THE STRONG CYCLONE...WITH SOME OF THE LOWEST SURFACE
PRESSURES IN THE EASTERN US ON 24 DECEMBER IN THE PAST 30 YEARS
WILL MOVE INTO THE GREAT LAKES. PRESSURE ANOMALIES ARE -3 TO -4
SIGMA BELOW NORMAL WITH A RETURN PERIOD ON THE ORDER OF 30 YEARS
IN SOME FORECAST SYSTEMS.

THE FRONT ASSOCIATED WITH THE CYCLONE PUSHES INTO OUR REGION
WEDNESDAY...AT THIS TIME THE 850 MB SOUTHERLY WINDS ARE FORECAST
TO BE ABOUT +3 SIGMA ABOVE NORMAL. THE STRONG SOUTHERLY FLOW...THE
HIGH PRECIPITABLE WATER...THE STRONG FRONT ALL IMPLY A FRONTAL
RAIN EVENT AND PERHAPS SOME RARE LATE DECEMBER (ELEVATED)
CONVECTION. IF THIS WERE AUTUMN OR SPRING WE MIGHT BE THINKING
QLCS. BUT SURFACE CAPE IS VIRTUALLY NON-EXISTENT BUT SHOWERY RAIN
AND PERHAPS ISOLATED THUNDER POSSIBLE.

DO NOT LIKE HAVING POPS ABOVE 60 TO 66 PERCENT AT DAY 5 IN 12 HOUR
PERIODS. TIMING WILL CLEARLY CHANGE BUT HAVE HIGH POPS FOR
CONSISTENCY WITH OTHER OFFICES.

CHRISTMAS EVE AND EARLY CHRISTMAS IS THE AREA OF HIGH UNCERTAINTY
AS TO WHEN THE COLD AIR COMES IN. THIS WILL DICTATE WHEN THE RAIN
COMES AND WHEN THE GUSTY WINDS SET IN. GRADIENTS ARE WHERE
FORECASTS ARE THEIR POOREST. BUT BY CHRISTMAS MORNING MOST IF NOT
ALL OF THE REGION SHOULD BE BELOW 0C AT 850 AND THE STRONG
WESTERLY WINDS SHOULD BE MIXING DOWN BEHIND THE FRONTAL BOUNDARY.
WINDY OVERNIGHT CHRISTMAS EVE INTO CHRISTMAS DAY. ANY RESIDUAL
PRECIPITATION SHOULD BE SNOW/SNOW SHOWERS AND FLURRIES.

TEMPERATURES SHOULD REBOUND FRIDAY AHEAD OF ANOTHER NORTHERN STREAM
WAVE MOVING INTO THE MID-WEST. THIS SHOULD RAISE OUR HEIGHTS AND
TEMPERATURES FRIDAY INTO EARLY SATURDAY. IT APPEARS A SERIES OF
WAVES MAY EVENTUALLY CARVE OUT A TROUGH OVER THE EAST-CENTRAL US. IF
SO...WE COULD END DECEMBER A BIT ON THE CHILLY SIDE.

&&

.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
SHALLOW STRATOCU DECK REMAINS TRAPPED BENEATH SUBSIDENCE
INVERSION THIS MORNING...WITH MVFR CIGS.  LOWER CIGS WILL PERSIST
IN THE NORTHERN MTNS...WITH IMPROVING CIGS CENTRAL AND SOUTH. WINDS
WILL BE LIGHT FROM THE WEST.

CIG RESTRICTIONS IN EXPANDING STRATOCU DECK LIKELY RETURN AGAIN
TONIGHT...THOUGH LOW CLOUDS SHOULD NOT BE QUITE AS EXPANSIVE AS
PREVIOUS NIGHTS. A SHORTWAVE WILL TRACK ACROSS THE REGION BRINGING
A THICKENING MID-LVL DECK AS WELL. SURFACE WINDS WILL CONTINUE TO
BE LIGHT...WITH SW FLOW ALOFT BEGINNING TO INCREASE AS A LARGE LOW
PRESSURE SYSTEM BEGINS TO DEEPEN OVER THE CENTRAL U.S.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

THU...WINDY AND COLDER WITH SCT MVFR CIGS AND -SHSN.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...DEVOIR/FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...GRUMM
AVIATION...DEVOIR/RXR




000
FXUS61 KCTP 201932
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
232 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE SLIDING EASTWARD THROUGH QUEBEC WITH A SECOND HIGH
PRESURE CELL OVER THE EASTERN GREAT LAKES AND OHIO VALLEY WILL
KEEP MAINTAIN DRY WEATHER ACROSS CENTRAL PENNSYLVANIA FOR THE REST
OF THIS WEEKEND. AN AMPLIFYING UPPER RIDGE MOVING INTO THE REGION
WILL BRING INCREASING AMOUNTS OF SUNSHINE ON SUNDAY...BUT WILL BE
QUICKLY REPLACED BY A LARGE STORM SYSTEM TRACKING ACROSS THE
CENTRAL UNITED STATES. MOISTURE ASSOCIATED WITH THAT STORM AND
INCREASING EAST FLOW OFF OF THE WESTERN ATLANTIC WILL BRING
INCREASING CLOUDS ON MONDAY...WITH QUITE MILD BUT UNSETTLED
CONDITIONS PREVAILING THROUGH MID WEEK. A VIGOROUS STORM SYSTEM
WILL SWEEP ACROSS THE COMMONWEALTH ON CHRISTMAS EVE BRINGING
WIDESPREAD SHOWERS AND A CHANCE FOR THUNDERSTORMS...FOLLOWED BY
WINDY AND COLDER CONDITIONS WITH SCATTERED SNOW SHOWERS AND
FLURRIES ACROSS THE WEST AND NORTH FOR CHRISTMAS DAY. MILDER
CONDITIONS WILL ARRIVE ONCE AGAIN BY LATE THIS WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
SUBSIDENCE AND DOWNSLOPING OVER MUCH OF THE LAUREL HIGHLANDS AND
PARTS OF THE CENTRAL AND SOUTH CENTRAL MOUNTAINS IS BRINGING SOME
MUCH NEEDED SUNSHINE TO THOSE AREAS. VISIBLE IMAGERY INDICATES THE
NORTHWARD EXTENT PUSHING TOWARDS CENTRAL CLEARFIELD COUNTY AND
SOUTHERN CENTRE COUNTY...AND IT APPEARS LIKELY TO REACH A LITTLE
FARTHER NORTH BEFORE SUNSET.

EXPECT CLOUDS TO FILL BACK IN OVERNIGHT...AS 5H WAVE TRACKS ACROSS
THE OHIO VALLEY AND INTO SOUTHWEST PA BY 12Z SUN. MINS WILL BE
FAIRLY UNIFORM AND RANGE FROM THE LOWER 20S NORTH TO THE UPPER 20S
SOUTHEAST.

&&

.SHORT TERM /SUNDAY/...
DEEP LAYER DRYING BEHIND THE AFOREMENTIONED DEPARTING 5H WAVE AND
UPPER LEVEL RIDGING HAS THE POTENTIAL TO BRING SUNSHINE TO MOST IF
NOT ALL OF CENTRAL PA ON MONDAY. THE STUBBORN STRATUS THAT HAS
PLAGUED US FOR MORE THAN A WEEK WILL HAVE A CHANCE TO MIX
OUT...BUT TRANSITORY SFC HIGH PRESSURE MAY STILL MAKE THIS A SLOW
PROCESS OVER THE NORTH.

PRIOR TO THAT...SOME AREAS COULD PERHAPS SEE A FLURRY IN THE PRE
DAWN HOURS SUNDAY BEFORE THE WAVE QUICKLY EXITS EASTWARD. WENT
CLOSE TO CONSALL GUIDANCE AGAIN WITH MAXES REACHING THE MID TO
UPPER 30S NORTH TO THE LOWER 40S SOUTH.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
INCREASINGLY MOIST SERLY FLOW WILL DEVELOP OFF THE ATLANTIC EARLY
NEXT WEEK IN GRADIENT BTWN RETREATING HIGH OVR NEW ENG AND WEAK
LOW RIDING UP THE E COAST. THE INFLUX OF LOW LVL MOISTURE...COMBINED
WITH OROGRAPHIC LIFT...WILL LIKELY YIELD DAMP AND DRIZZLY WX MON
NITE THROUGH TUESDAY. MDLS HINT AT PERHAPS JUST ENOUGH LOW LVL
COLD AIR FOR AN INITIAL PERIOD OF -FZRA/FZDZ OVR THE HIGHER
TERRAIN OF THE APPALACHIANS MON NITE.

MED RANGE GUIDANCE HAS CONVERGED ON TIMING/TRACK OF DEEP TROUGH
AND ASSOC SFC LOW DURING MID WEEK...ALL OF WHICH POINTS TOWARD A
MILD AND RAINY CHRISTMAS EVE IN WARM SECTOR OF THIS SYSTEM. BLEND
OF MED RANGE GUIDANCE SUPPORTS ARND 1 INCH OF RAIN...FALLING
MOSTLY WITH PASSAGE OF LL JET/PLUME OF ANOMALOUS PWATS WEDNESDAY.
SURGE OF VERY WARM AIR SHOULD PRECEDE THE TRAILING COLD FRONT...PUSHING
READINGS INTO THE 50S OVR MOST OF THE AREA WEDNESDAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS IS LIKELY WED NIGHT INTO THURSDAY OVR THE W MTNS...PERHAPS
BRINGING A WHITE XMAS TO THE ALLEGHENY PLATEAU. THE BIGGER STORY
MAY BE THE STRONG/GUSTY WINDS WED NITE/THURSDAY. DEEPENING SFC
LOWS TRACKING THRU THE E GRT LKS TYPICALLY BRING CENTRAL PA SOME
OF OUR STRONGEST WINDS AND LATEST GUIDANCE SUGGESTS WINDS COULD
BE NEAR ADVISORY CRITERIA ON CHRISTMAS.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
00Z ECENS AND GEFS SHOWING THE UPPER TROF QUICKLY LIFTING OUT BY
FRIDAY.

&&

.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
SHALLOW STRATOCU DECK REMAINS TRAPPED BENEATH SUBSIDENCE
INVERSION THIS MORNING...WITH MVFR CIGS.  LOWER CIGS WILL PERSIST
IN THE NORTHERN MTNS...WITH IMPROVING CIGS CENTRAL AND SOUTH. WINDS
WILL BE LIGHT FROM THE WEST.

CIG RESTRICTIONS IN EXPANDING STRATOCU DECK LIKELY RETURN AGAIN
TONIGHT...THOUGH LOW CLOUDS SHOULD NOT BE QUITE AS EXPANSIVE AS
PREVIOUS NIGHTS. A SHORTWAVE WILL TRACK ACROSS THE REGION BRINGING
A THICKENING MID-LVL DECK AS WELL. SURFACE WINDS WILL CONTINUE TO
BE LIGHT...WITH SW FLOW ALOFT BEGINNING TO INCREASE AS A LARGE LOW
PRESSURE SYSTEM BEGINS TO DEEPEN OVER THE CENTRAL U.S.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

THU...WINDY AND COLDER WITH SCT MVFR CIGS AND -SHSN.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...DEVOIR/FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/EVANEGO
AVIATION...DEVOIR/RXR




000
FXUS61 KCTP 201932
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
232 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE SLIDING EASTWARD THROUGH QUEBEC WITH A SECOND HIGH
PRESURE CELL OVER THE EASTERN GREAT LAKES AND OHIO VALLEY WILL
KEEP MAINTAIN DRY WEATHER ACROSS CENTRAL PENNSYLVANIA FOR THE REST
OF THIS WEEKEND. AN AMPLIFYING UPPER RIDGE MOVING INTO THE REGION
WILL BRING INCREASING AMOUNTS OF SUNSHINE ON SUNDAY...BUT WILL BE
QUICKLY REPLACED BY A LARGE STORM SYSTEM TRACKING ACROSS THE
CENTRAL UNITED STATES. MOISTURE ASSOCIATED WITH THAT STORM AND
INCREASING EAST FLOW OFF OF THE WESTERN ATLANTIC WILL BRING
INCREASING CLOUDS ON MONDAY...WITH QUITE MILD BUT UNSETTLED
CONDITIONS PREVAILING THROUGH MID WEEK. A VIGOROUS STORM SYSTEM
WILL SWEEP ACROSS THE COMMONWEALTH ON CHRISTMAS EVE BRINGING
WIDESPREAD SHOWERS AND A CHANCE FOR THUNDERSTORMS...FOLLOWED BY
WINDY AND COLDER CONDITIONS WITH SCATTERED SNOW SHOWERS AND
FLURRIES ACROSS THE WEST AND NORTH FOR CHRISTMAS DAY. MILDER
CONDITIONS WILL ARRIVE ONCE AGAIN BY LATE THIS WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
SUBSIDENCE AND DOWNSLOPING OVER MUCH OF THE LAUREL HIGHLANDS AND
PARTS OF THE CENTRAL AND SOUTH CENTRAL MOUNTAINS IS BRINGING SOME
MUCH NEEDED SUNSHINE TO THOSE AREAS. VISIBLE IMAGERY INDICATES THE
NORTHWARD EXTENT PUSHING TOWARDS CENTRAL CLEARFIELD COUNTY AND
SOUTHERN CENTRE COUNTY...AND IT APPEARS LIKELY TO REACH A LITTLE
FARTHER NORTH BEFORE SUNSET.

EXPECT CLOUDS TO FILL BACK IN OVERNIGHT...AS 5H WAVE TRACKS ACROSS
THE OHIO VALLEY AND INTO SOUTHWEST PA BY 12Z SUN. MINS WILL BE
FAIRLY UNIFORM AND RANGE FROM THE LOWER 20S NORTH TO THE UPPER 20S
SOUTHEAST.

&&

.SHORT TERM /SUNDAY/...
DEEP LAYER DRYING BEHIND THE AFOREMENTIONED DEPARTING 5H WAVE AND
UPPER LEVEL RIDGING HAS THE POTENTIAL TO BRING SUNSHINE TO MOST IF
NOT ALL OF CENTRAL PA ON MONDAY. THE STUBBORN STRATUS THAT HAS
PLAGUED US FOR MORE THAN A WEEK WILL HAVE A CHANCE TO MIX
OUT...BUT TRANSITORY SFC HIGH PRESSURE MAY STILL MAKE THIS A SLOW
PROCESS OVER THE NORTH.

PRIOR TO THAT...SOME AREAS COULD PERHAPS SEE A FLURRY IN THE PRE
DAWN HOURS SUNDAY BEFORE THE WAVE QUICKLY EXITS EASTWARD. WENT
CLOSE TO CONSALL GUIDANCE AGAIN WITH MAXES REACHING THE MID TO
UPPER 30S NORTH TO THE LOWER 40S SOUTH.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
INCREASINGLY MOIST SERLY FLOW WILL DEVELOP OFF THE ATLANTIC EARLY
NEXT WEEK IN GRADIENT BTWN RETREATING HIGH OVR NEW ENG AND WEAK
LOW RIDING UP THE E COAST. THE INFLUX OF LOW LVL MOISTURE...COMBINED
WITH OROGRAPHIC LIFT...WILL LIKELY YIELD DAMP AND DRIZZLY WX MON
NITE THROUGH TUESDAY. MDLS HINT AT PERHAPS JUST ENOUGH LOW LVL
COLD AIR FOR AN INITIAL PERIOD OF -FZRA/FZDZ OVR THE HIGHER
TERRAIN OF THE APPALACHIANS MON NITE.

MED RANGE GUIDANCE HAS CONVERGED ON TIMING/TRACK OF DEEP TROUGH
AND ASSOC SFC LOW DURING MID WEEK...ALL OF WHICH POINTS TOWARD A
MILD AND RAINY CHRISTMAS EVE IN WARM SECTOR OF THIS SYSTEM. BLEND
OF MED RANGE GUIDANCE SUPPORTS ARND 1 INCH OF RAIN...FALLING
MOSTLY WITH PASSAGE OF LL JET/PLUME OF ANOMALOUS PWATS WEDNESDAY.
SURGE OF VERY WARM AIR SHOULD PRECEDE THE TRAILING COLD FRONT...PUSHING
READINGS INTO THE 50S OVR MOST OF THE AREA WEDNESDAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS IS LIKELY WED NIGHT INTO THURSDAY OVR THE W MTNS...PERHAPS
BRINGING A WHITE XMAS TO THE ALLEGHENY PLATEAU. THE BIGGER STORY
MAY BE THE STRONG/GUSTY WINDS WED NITE/THURSDAY. DEEPENING SFC
LOWS TRACKING THRU THE E GRT LKS TYPICALLY BRING CENTRAL PA SOME
OF OUR STRONGEST WINDS AND LATEST GUIDANCE SUGGESTS WINDS COULD
BE NEAR ADVISORY CRITERIA ON CHRISTMAS.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
00Z ECENS AND GEFS SHOWING THE UPPER TROF QUICKLY LIFTING OUT BY
FRIDAY.

&&

.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
SHALLOW STRATOCU DECK REMAINS TRAPPED BENEATH SUBSIDENCE
INVERSION THIS MORNING...WITH MVFR CIGS.  LOWER CIGS WILL PERSIST
IN THE NORTHERN MTNS...WITH IMPROVING CIGS CENTRAL AND SOUTH. WINDS
WILL BE LIGHT FROM THE WEST.

CIG RESTRICTIONS IN EXPANDING STRATOCU DECK LIKELY RETURN AGAIN
TONIGHT...THOUGH LOW CLOUDS SHOULD NOT BE QUITE AS EXPANSIVE AS
PREVIOUS NIGHTS. A SHORTWAVE WILL TRACK ACROSS THE REGION BRINGING
A THICKENING MID-LVL DECK AS WELL. SURFACE WINDS WILL CONTINUE TO
BE LIGHT...WITH SW FLOW ALOFT BEGINNING TO INCREASE AS A LARGE LOW
PRESSURE SYSTEM BEGINS TO DEEPEN OVER THE CENTRAL U.S.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

THU...WINDY AND COLDER WITH SCT MVFR CIGS AND -SHSN.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...DEVOIR/FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/EVANEGO
AVIATION...DEVOIR/RXR




000
FXUS61 KCTP 201932
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
232 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE SLIDING EASTWARD THROUGH QUEBEC WITH A SECOND HIGH
PRESURE CELL OVER THE EASTERN GREAT LAKES AND OHIO VALLEY WILL
KEEP MAINTAIN DRY WEATHER ACROSS CENTRAL PENNSYLVANIA FOR THE REST
OF THIS WEEKEND. AN AMPLIFYING UPPER RIDGE MOVING INTO THE REGION
WILL BRING INCREASING AMOUNTS OF SUNSHINE ON SUNDAY...BUT WILL BE
QUICKLY REPLACED BY A LARGE STORM SYSTEM TRACKING ACROSS THE
CENTRAL UNITED STATES. MOISTURE ASSOCIATED WITH THAT STORM AND
INCREASING EAST FLOW OFF OF THE WESTERN ATLANTIC WILL BRING
INCREASING CLOUDS ON MONDAY...WITH QUITE MILD BUT UNSETTLED
CONDITIONS PREVAILING THROUGH MID WEEK. A VIGOROUS STORM SYSTEM
WILL SWEEP ACROSS THE COMMONWEALTH ON CHRISTMAS EVE BRINGING
WIDESPREAD SHOWERS AND A CHANCE FOR THUNDERSTORMS...FOLLOWED BY
WINDY AND COLDER CONDITIONS WITH SCATTERED SNOW SHOWERS AND
FLURRIES ACROSS THE WEST AND NORTH FOR CHRISTMAS DAY. MILDER
CONDITIONS WILL ARRIVE ONCE AGAIN BY LATE THIS WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
SUBSIDENCE AND DOWNSLOPING OVER MUCH OF THE LAUREL HIGHLANDS AND
PARTS OF THE CENTRAL AND SOUTH CENTRAL MOUNTAINS IS BRINGING SOME
MUCH NEEDED SUNSHINE TO THOSE AREAS. VISIBLE IMAGERY INDICATES THE
NORTHWARD EXTENT PUSHING TOWARDS CENTRAL CLEARFIELD COUNTY AND
SOUTHERN CENTRE COUNTY...AND IT APPEARS LIKELY TO REACH A LITTLE
FARTHER NORTH BEFORE SUNSET.

EXPECT CLOUDS TO FILL BACK IN OVERNIGHT...AS 5H WAVE TRACKS ACROSS
THE OHIO VALLEY AND INTO SOUTHWEST PA BY 12Z SUN. MINS WILL BE
FAIRLY UNIFORM AND RANGE FROM THE LOWER 20S NORTH TO THE UPPER 20S
SOUTHEAST.

&&

.SHORT TERM /SUNDAY/...
DEEP LAYER DRYING BEHIND THE AFOREMENTIONED DEPARTING 5H WAVE AND
UPPER LEVEL RIDGING HAS THE POTENTIAL TO BRING SUNSHINE TO MOST IF
NOT ALL OF CENTRAL PA ON MONDAY. THE STUBBORN STRATUS THAT HAS
PLAGUED US FOR MORE THAN A WEEK WILL HAVE A CHANCE TO MIX
OUT...BUT TRANSITORY SFC HIGH PRESSURE MAY STILL MAKE THIS A SLOW
PROCESS OVER THE NORTH.

PRIOR TO THAT...SOME AREAS COULD PERHAPS SEE A FLURRY IN THE PRE
DAWN HOURS SUNDAY BEFORE THE WAVE QUICKLY EXITS EASTWARD. WENT
CLOSE TO CONSALL GUIDANCE AGAIN WITH MAXES REACHING THE MID TO
UPPER 30S NORTH TO THE LOWER 40S SOUTH.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
INCREASINGLY MOIST SERLY FLOW WILL DEVELOP OFF THE ATLANTIC EARLY
NEXT WEEK IN GRADIENT BTWN RETREATING HIGH OVR NEW ENG AND WEAK
LOW RIDING UP THE E COAST. THE INFLUX OF LOW LVL MOISTURE...COMBINED
WITH OROGRAPHIC LIFT...WILL LIKELY YIELD DAMP AND DRIZZLY WX MON
NITE THROUGH TUESDAY. MDLS HINT AT PERHAPS JUST ENOUGH LOW LVL
COLD AIR FOR AN INITIAL PERIOD OF -FZRA/FZDZ OVR THE HIGHER
TERRAIN OF THE APPALACHIANS MON NITE.

MED RANGE GUIDANCE HAS CONVERGED ON TIMING/TRACK OF DEEP TROUGH
AND ASSOC SFC LOW DURING MID WEEK...ALL OF WHICH POINTS TOWARD A
MILD AND RAINY CHRISTMAS EVE IN WARM SECTOR OF THIS SYSTEM. BLEND
OF MED RANGE GUIDANCE SUPPORTS ARND 1 INCH OF RAIN...FALLING
MOSTLY WITH PASSAGE OF LL JET/PLUME OF ANOMALOUS PWATS WEDNESDAY.
SURGE OF VERY WARM AIR SHOULD PRECEDE THE TRAILING COLD FRONT...PUSHING
READINGS INTO THE 50S OVR MOST OF THE AREA WEDNESDAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS IS LIKELY WED NIGHT INTO THURSDAY OVR THE W MTNS...PERHAPS
BRINGING A WHITE XMAS TO THE ALLEGHENY PLATEAU. THE BIGGER STORY
MAY BE THE STRONG/GUSTY WINDS WED NITE/THURSDAY. DEEPENING SFC
LOWS TRACKING THRU THE E GRT LKS TYPICALLY BRING CENTRAL PA SOME
OF OUR STRONGEST WINDS AND LATEST GUIDANCE SUGGESTS WINDS COULD
BE NEAR ADVISORY CRITERIA ON CHRISTMAS.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
00Z ECENS AND GEFS SHOWING THE UPPER TROF QUICKLY LIFTING OUT BY
FRIDAY.

&&

.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
SHALLOW STRATOCU DECK REMAINS TRAPPED BENEATH SUBSIDENCE
INVERSION THIS MORNING...WITH MVFR CIGS.  LOWER CIGS WILL PERSIST
IN THE NORTHERN MTNS...WITH IMPROVING CIGS CENTRAL AND SOUTH. WINDS
WILL BE LIGHT FROM THE WEST.

CIG RESTRICTIONS IN EXPANDING STRATOCU DECK LIKELY RETURN AGAIN
TONIGHT...THOUGH LOW CLOUDS SHOULD NOT BE QUITE AS EXPANSIVE AS
PREVIOUS NIGHTS. A SHORTWAVE WILL TRACK ACROSS THE REGION BRINGING
A THICKENING MID-LVL DECK AS WELL. SURFACE WINDS WILL CONTINUE TO
BE LIGHT...WITH SW FLOW ALOFT BEGINNING TO INCREASE AS A LARGE LOW
PRESSURE SYSTEM BEGINS TO DEEPEN OVER THE CENTRAL U.S.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

THU...WINDY AND COLDER WITH SCT MVFR CIGS AND -SHSN.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...DEVOIR/FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/EVANEGO
AVIATION...DEVOIR/RXR




000
FXUS61 KCTP 201932
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
232 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE SLIDING EASTWARD THROUGH QUEBEC WITH A SECOND HIGH
PRESURE CELL OVER THE EASTERN GREAT LAKES AND OHIO VALLEY WILL
KEEP MAINTAIN DRY WEATHER ACROSS CENTRAL PENNSYLVANIA FOR THE REST
OF THIS WEEKEND. AN AMPLIFYING UPPER RIDGE MOVING INTO THE REGION
WILL BRING INCREASING AMOUNTS OF SUNSHINE ON SUNDAY...BUT WILL BE
QUICKLY REPLACED BY A LARGE STORM SYSTEM TRACKING ACROSS THE
CENTRAL UNITED STATES. MOISTURE ASSOCIATED WITH THAT STORM AND
INCREASING EAST FLOW OFF OF THE WESTERN ATLANTIC WILL BRING
INCREASING CLOUDS ON MONDAY...WITH QUITE MILD BUT UNSETTLED
CONDITIONS PREVAILING THROUGH MID WEEK. A VIGOROUS STORM SYSTEM
WILL SWEEP ACROSS THE COMMONWEALTH ON CHRISTMAS EVE BRINGING
WIDESPREAD SHOWERS AND A CHANCE FOR THUNDERSTORMS...FOLLOWED BY
WINDY AND COLDER CONDITIONS WITH SCATTERED SNOW SHOWERS AND
FLURRIES ACROSS THE WEST AND NORTH FOR CHRISTMAS DAY. MILDER
CONDITIONS WILL ARRIVE ONCE AGAIN BY LATE THIS WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
SUBSIDENCE AND DOWNSLOPING OVER MUCH OF THE LAUREL HIGHLANDS AND
PARTS OF THE CENTRAL AND SOUTH CENTRAL MOUNTAINS IS BRINGING SOME
MUCH NEEDED SUNSHINE TO THOSE AREAS. VISIBLE IMAGERY INDICATES THE
NORTHWARD EXTENT PUSHING TOWARDS CENTRAL CLEARFIELD COUNTY AND
SOUTHERN CENTRE COUNTY...AND IT APPEARS LIKELY TO REACH A LITTLE
FARTHER NORTH BEFORE SUNSET.

EXPECT CLOUDS TO FILL BACK IN OVERNIGHT...AS 5H WAVE TRACKS ACROSS
THE OHIO VALLEY AND INTO SOUTHWEST PA BY 12Z SUN. MINS WILL BE
FAIRLY UNIFORM AND RANGE FROM THE LOWER 20S NORTH TO THE UPPER 20S
SOUTHEAST.

&&

.SHORT TERM /SUNDAY/...
DEEP LAYER DRYING BEHIND THE AFOREMENTIONED DEPARTING 5H WAVE AND
UPPER LEVEL RIDGING HAS THE POTENTIAL TO BRING SUNSHINE TO MOST IF
NOT ALL OF CENTRAL PA ON MONDAY. THE STUBBORN STRATUS THAT HAS
PLAGUED US FOR MORE THAN A WEEK WILL HAVE A CHANCE TO MIX
OUT...BUT TRANSITORY SFC HIGH PRESSURE MAY STILL MAKE THIS A SLOW
PROCESS OVER THE NORTH.

PRIOR TO THAT...SOME AREAS COULD PERHAPS SEE A FLURRY IN THE PRE
DAWN HOURS SUNDAY BEFORE THE WAVE QUICKLY EXITS EASTWARD. WENT
CLOSE TO CONSALL GUIDANCE AGAIN WITH MAXES REACHING THE MID TO
UPPER 30S NORTH TO THE LOWER 40S SOUTH.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
INCREASINGLY MOIST SERLY FLOW WILL DEVELOP OFF THE ATLANTIC EARLY
NEXT WEEK IN GRADIENT BTWN RETREATING HIGH OVR NEW ENG AND WEAK
LOW RIDING UP THE E COAST. THE INFLUX OF LOW LVL MOISTURE...COMBINED
WITH OROGRAPHIC LIFT...WILL LIKELY YIELD DAMP AND DRIZZLY WX MON
NITE THROUGH TUESDAY. MDLS HINT AT PERHAPS JUST ENOUGH LOW LVL
COLD AIR FOR AN INITIAL PERIOD OF -FZRA/FZDZ OVR THE HIGHER
TERRAIN OF THE APPALACHIANS MON NITE.

MED RANGE GUIDANCE HAS CONVERGED ON TIMING/TRACK OF DEEP TROUGH
AND ASSOC SFC LOW DURING MID WEEK...ALL OF WHICH POINTS TOWARD A
MILD AND RAINY CHRISTMAS EVE IN WARM SECTOR OF THIS SYSTEM. BLEND
OF MED RANGE GUIDANCE SUPPORTS ARND 1 INCH OF RAIN...FALLING
MOSTLY WITH PASSAGE OF LL JET/PLUME OF ANOMALOUS PWATS WEDNESDAY.
SURGE OF VERY WARM AIR SHOULD PRECEDE THE TRAILING COLD FRONT...PUSHING
READINGS INTO THE 50S OVR MOST OF THE AREA WEDNESDAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS IS LIKELY WED NIGHT INTO THURSDAY OVR THE W MTNS...PERHAPS
BRINGING A WHITE XMAS TO THE ALLEGHENY PLATEAU. THE BIGGER STORY
MAY BE THE STRONG/GUSTY WINDS WED NITE/THURSDAY. DEEPENING SFC
LOWS TRACKING THRU THE E GRT LKS TYPICALLY BRING CENTRAL PA SOME
OF OUR STRONGEST WINDS AND LATEST GUIDANCE SUGGESTS WINDS COULD
BE NEAR ADVISORY CRITERIA ON CHRISTMAS.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
00Z ECENS AND GEFS SHOWING THE UPPER TROF QUICKLY LIFTING OUT BY
FRIDAY.

&&

.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
SHALLOW STRATOCU DECK REMAINS TRAPPED BENEATH SUBSIDENCE
INVERSION THIS MORNING...WITH MVFR CIGS.  LOWER CIGS WILL PERSIST
IN THE NORTHERN MTNS...WITH IMPROVING CIGS CENTRAL AND SOUTH. WINDS
WILL BE LIGHT FROM THE WEST.

CIG RESTRICTIONS IN EXPANDING STRATOCU DECK LIKELY RETURN AGAIN
TONIGHT...THOUGH LOW CLOUDS SHOULD NOT BE QUITE AS EXPANSIVE AS
PREVIOUS NIGHTS. A SHORTWAVE WILL TRACK ACROSS THE REGION BRINGING
A THICKENING MID-LVL DECK AS WELL. SURFACE WINDS WILL CONTINUE TO
BE LIGHT...WITH SW FLOW ALOFT BEGINNING TO INCREASE AS A LARGE LOW
PRESSURE SYSTEM BEGINS TO DEEPEN OVER THE CENTRAL U.S.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

THU...WINDY AND COLDER WITH SCT MVFR CIGS AND -SHSN.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...DEVOIR/FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/EVANEGO
AVIATION...DEVOIR/RXR




000
FXUS61 KPBZ 201912
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
212 PM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE IN CONTROL INTO MONDAY. INCREASING PRECIPITATION
CHANCES TUESDAY. STORM SYSTEM BRINGS RAIN AND WIND CHRISTMAS
EVE...AND SNOW SHOWERS CHRISTMAS DAY.

&&

.NEAR TERM /THROUGH SUNDAY/...
WEAKER INVERSION ACROSS PORTIONS OF SOUTHERN PA HAS ALLOWED LOWER
CLOUDS TO BREAK UP SOMEWHAT...ALTHOUGH THEY ARE HANGING TOUGH SO FAR
ACROSS THE NORTHERN COUNTIES NEAR FKL/DUJ AS WELL AS IN SOUTHEAST
OHIO.  EXPECT THESE TO REFORM TONIGHT AS INVERSION SHARPENS UP AGAIN
IN VERY WEAK FLOW...THUS GOING MOSTLY CLOUDY MOST AREAS.  GOING TO HANG
ON TO SLIGHT CHANCE POPS IN THE SOUTHEAST WITH SHORTWAVE TROUGH
MOVING ACROSS AND SLIGHTLY BETTER MOISTURE PROFILE...BUT SNOW
ACCUMULATION IS NOT EXPECTED.  THIS POSSIBILITY ENDS BY 09Z. ONLY
MINOR MODIFICATION TO GENERALLY SEASONABLE TEMPERATURES.

INVERSION IS MAINTAINED SUNDAY MORNING...BUT BY AFTERNOON EXPECT
STRATUS TO MIX OUT INTO A CU FIELD AND THEN SCATTER OUT BY EVENING.
A BIT MORE SUN SHOULD ALLOW FOR AFTERNOON HIGH TEMPS AROUND 5
DEGREES WARMER THAN TODAY. CL

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
BENIGN WEATHER INITIALLY WITH HIGH PRESSURE TO OUR EAST AND IN
CONTROL.  SOUTHEAST WINDS IN RESPONSE TO SURFACE ANTICYCLONE
POSITION WILL FACILITATE DEVELOPMENT OF STRATUS OVER EASTERN
PORTIONS OF TUCKER AND GARRETT COUNTIES MONDAY INTO MONDAY NIGHT.
PCPN ONSET HAS SLOWED DOWN FROM PREVIOUS CYCLES...BUT THERE REMAINS
A VERY LOW PROBABILITY OF FREEZING RAIN AND/OR SLEET OVER
AFOREMENTIONED AREAS MONDAY.  FOR NOW...TRENDED FORECAST WITH PCPN
COMMENCING DURING THE AFTERNOON WHICH REFLECT LATEST NUMERICAL
MODELS.  WITH THIS SCENARIO...LOW LEVEL SUB-FREEZING AIR SHOULD
SCOUR OUT YIELDING AN ALL RAIN PTYPE.

RAIN SHADOW EFFECT TAKES PLACES TUESDAY WITH SOUTHEAST WINDS
WIDESPREAD OVER THE REGION. AN ISOLATED SHOWER REACHING EASTERN OHIO
AND FAR NWRN PA IS NOT OUT OF THE QUESTION...SO KEPT A SLIGHT
CHANCE.  WOULD NOT BE SURPRISED TO SEE BREAKS IN THE CLOUDS WHICH
COULD ALLOW FOR A FEW LOCATIONS TO EXCEED 60 DEGREES.  RECORD HIGHS
FOR PITTSBURGH...MORGANTOWN...AND ZANESVILLE ALL RESIDE WELL INTO
THE UPPER 60S...SO AT THIS JUNCTURE RECORD WARMTH IS NOT FORESEEN.
PRECIP ASSOCIATED WITH THE SURFACE LOW PRESSURE SYSTEM EJECTING FROM
THE GULF COAST REGION REACHES SERN AREAS OF THE FORECAST AREA THAT
EVENING.

A BLEND OF THE ONGOING FORECAST AND BIAS CORRECTED ECMWF WERE USED
FOR TEMPERATURES.

&&

.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
HIGHLIGHTS:
- A WET CHRISTMAS EVE
- TEMPERATURES RETURN BACK TO NORMAL VALUES CHRISTMAS DAY
- SLIGHTLY ABOVE NORMAL TEMPERATURES RETURN BY FRIDAY

STRONG LOW PRESSURE SYSTEM THAT HAS BEEN MUCH ADVERTISED GIVEN THE
TIME PERIOD WHICH IT AFFECTS OUR AREA IS STILL ON TRACK.  LONG RANGE
ENSEMBLE PREDICTION SYSTEMS AND OPERATIONAL MODELS ARE CONVERGING ON
A TRACK THROUGH IND / ILL THEN NORTH INTO CANADA.  THIS WILL MAKE
FOR ALL LIQUID PRECIPITATION ON THE FRONT END.  TEMPERATURES WILL
SOAR TO NEARLY 20 DEGREES ABOVE NORMAL WEDNESDAY WITH 50S COMMON.
COUPLED WITH INFLUX OF MOISTURE FROM THE GULF OF MEXICO...SOUNDINGS
ILLUSTRATE ELEVATED INSTABILITY WHICH PUSHES TEMP DIFFERENTIAL
BETWEEN H8 AND H5 TO NEARLY 0C.  THIS COULD LEAD TO ISOLATED
THUNDERSTORMS AHEAD OF THE BAROCLINIC ZONE.  FOR THE TIME
BEING...OPTED TO LEAVE THUNDER OUT OF THE FORECAST AND WAIT FOR
BETTER CONTINUITY GIVEN THIS STILL IS FIVE DAYS OUT.  DESPITE PWATS
NEARLY TWO STANDARD DEVIATIONS ABOVE NORMAL...COMBINATION OF
KATABATIC WINDS AND DRY CONVEYOR BELT WILL LIMIT QPF POTENTIAL TO
NEGATE ANY FLOOD THREAT.  LONG RANGE HYDROLOGIC MODELS SHOW VERY
LITTLE RISE IN AREA RIVERS...WHICH CORRELATES WELL TO THE PROJECTED
QPF OF 0.50 TO 1.00".

WITH THE TRACK OF THE CYCLONE DUE N...COLD AIR INJECTED INTO THE
AREA WILL BE OF MIDWEST ORIGIN...SO TEMPS WILL RETREAT BACK TO
SEASONAL BENCHMARKS CHRISTMAS DAY.  FOR THOSE WHO ARE LOOKING FOR
SNOW ON CHRISTMAS...A CHANCE OF SNOW SHOWERS EXIST...BUT GIVEN
TRAJECTORY FROM THE SOUTHWEST ANY ACCUMULATION ASSOCIATED WITH THE
UPPER LEVEL SYSTEM WILL BE LIGHT AT BEST.  HISTORICALLY...THERE IS
ONLY A 17 PERCENT CHANCE OF AT LEAST ONE INCH OF SNOW ON THE GROUND
AT PITTSBURGH CHRISTMAS MORNING.

H8 WINDS PUSH 50KTS WEDNESDAY NIGHT INTO THURSDAY AND HIGHEST
ANOMALIES RESIDE ALONG THE LAKE SHORE...SO EXPECT HIGHEST GUSTS
WOULD DO SO AS WELL.  NONETHELESS...PERIOD FROM WEDNESDAY NIGHT INTO
THURSDAY STRONG ISALLOBARIC FLOW COULD YIELD GUSTS IN EXCESS OF 40
MPH ESPECIALLY IN THE MOUNTAINS OF WRN MD AND NRN WV.

BALANCE OF THE EXTENDED IS CHARACTERIZED BY UNCERTAINTY AS ONE WOULD
EXPECT IN THE DAY 6 -7 TIME FRAME.  ECMWF HAS A STRONGER SYSTEM
CROSSING FRIDAY NIGHT VERSUS GFS WHICH IS MUCH WEAKER.  EITHER CASE
PTYPE SHOULD BE RAIN WITH SNOW SHOWERS ON THE BACKSIDE.  NO PLUNGES
OF ARCTIC AIR ARE FORECAST IN THE NEXT 10 DAYS.  MAX/MIN
TEMPERATURES WERE A BLEND OF THE FORECAST AND ECMWF BIAS CORRECTED
DATA SET.

&&

.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
CLOUDS HAVE MANAGED TO THIN SOMEWHAT ACROSS SOUTHERN PA/NORTHERN
WV AND EXPECT THIS TO PERSIST FOR A FEW HOURS. HOWEVER...SW FLOW
WILL BRING A BIT MORE MOISTURE ALOFT...AS WELL AS WARM
ADVECTION...WHICH WILL HELP TO SHARPEN UP THE INVERSION ALOFT.
THUS...EXPECTING MOST AREAS TO SEE MVFR CIGS BECOME REESTABLISHED
BY THE LATE EVENING HOURS...AND PERSIST THROUGH THE REST OF THE
TAF PERIOD. CANNOT RULE OUT A FEW SNOWFLAKES TONIGHT IN LOCATIONS
LIKE MGW AND LBE...BUT THIS IS NOT EXPECTED TO CREATE ANY
RESTRICTIONS. ZZV COULD SEE SOME BREAKUP PAST 15Z THOUGH. WINDS
WILL REMAIN CALM OR VERY LIGHT.


OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
NEXT STORM SYSTEM WILL BEGIN TO IMPACT THE REGION ON TUESDAY AND
RESULT IN WIDESPREAD RAIN...CIG/VIS RESTRICTIONS...AND PERIODS OF
LLWS INTO THURSDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$






000
FXUS61 KPBZ 201733
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
1233 PM EST SAT DEC 20 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
SHORTWAVE TROUGH WILL SWING THROUGH THE OHIO VALLEY AND ACROSS THE
CWA DURING THE EARLY PART OF THE NIGHT. EXPECTING CLOUD COVER TO
BE MAINTAINED THROUGH THE PERIOD WITH AN OVERALL THIN BUT
PERSISTENT MOISTURE LAYER A COUPLE THOUSAND FEET UP.  WHILE
MOISTURE IS OTHERWISE FAIRLY MEAGER AT PRESENT...SW FLOW AT H850
WILL HELP PUSH MARGINALLY BETTER PWAT VALUES INTO THE SOUTHERN
COUNTIES BY SUNSET. THIS COMBINED WITH MODEST SUPPORT FROM SHORTWAVE MAY
ALLOW A FEW SNOWFLAKES TO SQUEEZE OUT...SO ADDED A SLIGHT CHANCE
POP TO THE GRIDS...MAINLY FOR THE EVENING...GENERALLY SOUTH OF A
HLG/PIT/IDI LINE. ANY ACTIVITY SHOULD END SOON AFTER 06Z WITH
SHORTWAVE DEPARTURE. TEMPERATURE FORECAST LOOKS DECENT OVERALL AT
THIS TIME.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY/...
MODELS ARE SHOWING SOME IMPROVEMENT SUNDAY...PARTICULARLY OVER
THE WEST AND FAR SOUTH. HOWEVER...MODEL SOUNDINGS FOR THE REST OF
THE REGION STILL WANT TO MAINTAIN A SATURATED LAYER AROUND 2500FT
FOR MOST OF THE DAY...WHICH DOES NOT PRESENT MUCH HOPE FOR
SUNSHINE. CLOUDS WILL BE TRICKY ON SUNDAY...TRYING TO DETERMINE
HOW MUCH OF THE CLOUD DECK WILL BE ERODED.

SPLIT FLOW DEVELOPS ON MONDAY WITH A LARGE SYSTEM TO THE WEST AND
ANOTHER SYSTEM TO THE SOUTH-SOUTHEAST. IT APPEARS THAT THE AREA
WILL LIE IN BETWEEN LIMITING THE CHANCES FOR PRECIPITATION. WAA
WILL CONTINUE ON MONDAY AND LOW-LEVEL MOISTURE INCREASES ONCE
AGAIN. LOOKS LIKE A GOOD DEAL OF CLOUD COVER AGAIN MONDAY. A WEAK
AND UNORGANIZED SHORTWAVE TROUGH WILL SWING THROUGH MONDAY...
ALLOWING FOR THE POSSIBILITY OF SOME LIGHT PRECIP...MAINLY OVER
THE SOUTHERN RIDGES. THIS WILL NEED TO BE FINE TUNED AS THE WARMER
AIR ALOFT MAY OCCUR BEFORE SURFACE TEMPS RESPOND. CONFIDENCE IS
LOW THAT ANY PRECIP WILL OCCUR...SO FOR FORECAST WILL LEAVE OUT.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
STILL SEEING SOME MINOR DIFFERENCES IN MEDIUM RANGE MODEL
SOLUTIONS FOR MIDWEEK SYSTEM. THINK MUCH OF TUESDAY COULD BE DRY
OR JUST LIGHT SHOWERS AS AREA WILL BE WELL INTO THE WARM SECTOR. RAIN
WILL OVERSPREAD THE AREA TUESDAY NIGHT AHEAD OF OCCLUDED FRONT AND
CONTINUE THROUGH WEDNESDAY. COLDER AIR WILL MOVE IN LATER
WEDNESDAY NIGHT CHANGING ANY LINGERING SHOWERS TO SNOW SHOWERS.
COULD SEE A BRIEF UPTICK IN SNOW SHOWER COVERAGE EARLY THURSDAY
MORNING AS MAIN TROUGH SWINGS THROUGH. COLD AIR WILL BE IN PLACE
THURSDAY...BUT WIND DIRECTION NOT OPTIMAL FOR LAKE INFLUENCED SNOW
SHOWERS.

WARMER AIR WILL MOVE BACK IN THURSDAY NIGHT AND FRIDAY.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
CLOUDS HAVE MANAGED TO THIN SOMEWHAT ACROSS SOUTHERN PA/NORTHERN
WV AND EXPECT THIS TO PERSIST FOR A FEW HOURS. HOWEVER...SW FLOW
WILL BRING A BIT MORE MOISTURE ALOFT...AS WELL AS WARM
ADVECTION...WHICH WILL HELP TO SHARPEN UP THE INVERSION ALOFT.
THUS...EXPECTING MOST AREAS TO SEE MVFR CIGS BECOME REESTABLISHED
BY THE LATE EVENING HOURS...AND PERSIST THROUGH THE REST OF THE
TAF PERIOD. CANNOT RULE OUT A FEW SNOWFLAKES TONIGHT IN LOCATIONS
LIKE MGW AND LBE...BUT THIS IS NOT EXPECTED TO CREATE ANY
RESTRICTIONS. ZZV COULD SEE SOME BREAKUP PAST 15Z THOUGH. WINDS
WILL REMAIN CALM OR VERY LIGHT.


OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
NEXT STORM SYSTEM WILL BEGIN TO IMPACT THE REGION ON TUESDAY AND
RESULT IN WIDESPREAD RAIN...CIG/VIS RESTRICTIONS...AND PERIODS OF
LLWS INTO THURSDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$






000
FXUS61 KPBZ 201733
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
1233 PM EST SAT DEC 20 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
SHORTWAVE TROUGH WILL SWING THROUGH THE OHIO VALLEY AND ACROSS THE
CWA DURING THE EARLY PART OF THE NIGHT. EXPECTING CLOUD COVER TO
BE MAINTAINED THROUGH THE PERIOD WITH AN OVERALL THIN BUT
PERSISTENT MOISTURE LAYER A COUPLE THOUSAND FEET UP.  WHILE
MOISTURE IS OTHERWISE FAIRLY MEAGER AT PRESENT...SW FLOW AT H850
WILL HELP PUSH MARGINALLY BETTER PWAT VALUES INTO THE SOUTHERN
COUNTIES BY SUNSET. THIS COMBINED WITH MODEST SUPPORT FROM SHORTWAVE MAY
ALLOW A FEW SNOWFLAKES TO SQUEEZE OUT...SO ADDED A SLIGHT CHANCE
POP TO THE GRIDS...MAINLY FOR THE EVENING...GENERALLY SOUTH OF A
HLG/PIT/IDI LINE. ANY ACTIVITY SHOULD END SOON AFTER 06Z WITH
SHORTWAVE DEPARTURE. TEMPERATURE FORECAST LOOKS DECENT OVERALL AT
THIS TIME.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY/...
MODELS ARE SHOWING SOME IMPROVEMENT SUNDAY...PARTICULARLY OVER
THE WEST AND FAR SOUTH. HOWEVER...MODEL SOUNDINGS FOR THE REST OF
THE REGION STILL WANT TO MAINTAIN A SATURATED LAYER AROUND 2500FT
FOR MOST OF THE DAY...WHICH DOES NOT PRESENT MUCH HOPE FOR
SUNSHINE. CLOUDS WILL BE TRICKY ON SUNDAY...TRYING TO DETERMINE
HOW MUCH OF THE CLOUD DECK WILL BE ERODED.

SPLIT FLOW DEVELOPS ON MONDAY WITH A LARGE SYSTEM TO THE WEST AND
ANOTHER SYSTEM TO THE SOUTH-SOUTHEAST. IT APPEARS THAT THE AREA
WILL LIE IN BETWEEN LIMITING THE CHANCES FOR PRECIPITATION. WAA
WILL CONTINUE ON MONDAY AND LOW-LEVEL MOISTURE INCREASES ONCE
AGAIN. LOOKS LIKE A GOOD DEAL OF CLOUD COVER AGAIN MONDAY. A WEAK
AND UNORGANIZED SHORTWAVE TROUGH WILL SWING THROUGH MONDAY...
ALLOWING FOR THE POSSIBILITY OF SOME LIGHT PRECIP...MAINLY OVER
THE SOUTHERN RIDGES. THIS WILL NEED TO BE FINE TUNED AS THE WARMER
AIR ALOFT MAY OCCUR BEFORE SURFACE TEMPS RESPOND. CONFIDENCE IS
LOW THAT ANY PRECIP WILL OCCUR...SO FOR FORECAST WILL LEAVE OUT.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
STILL SEEING SOME MINOR DIFFERENCES IN MEDIUM RANGE MODEL
SOLUTIONS FOR MIDWEEK SYSTEM. THINK MUCH OF TUESDAY COULD BE DRY
OR JUST LIGHT SHOWERS AS AREA WILL BE WELL INTO THE WARM SECTOR. RAIN
WILL OVERSPREAD THE AREA TUESDAY NIGHT AHEAD OF OCCLUDED FRONT AND
CONTINUE THROUGH WEDNESDAY. COLDER AIR WILL MOVE IN LATER
WEDNESDAY NIGHT CHANGING ANY LINGERING SHOWERS TO SNOW SHOWERS.
COULD SEE A BRIEF UPTICK IN SNOW SHOWER COVERAGE EARLY THURSDAY
MORNING AS MAIN TROUGH SWINGS THROUGH. COLD AIR WILL BE IN PLACE
THURSDAY...BUT WIND DIRECTION NOT OPTIMAL FOR LAKE INFLUENCED SNOW
SHOWERS.

WARMER AIR WILL MOVE BACK IN THURSDAY NIGHT AND FRIDAY.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
CLOUDS HAVE MANAGED TO THIN SOMEWHAT ACROSS SOUTHERN PA/NORTHERN
WV AND EXPECT THIS TO PERSIST FOR A FEW HOURS. HOWEVER...SW FLOW
WILL BRING A BIT MORE MOISTURE ALOFT...AS WELL AS WARM
ADVECTION...WHICH WILL HELP TO SHARPEN UP THE INVERSION ALOFT.
THUS...EXPECTING MOST AREAS TO SEE MVFR CIGS BECOME REESTABLISHED
BY THE LATE EVENING HOURS...AND PERSIST THROUGH THE REST OF THE
TAF PERIOD. CANNOT RULE OUT A FEW SNOWFLAKES TONIGHT IN LOCATIONS
LIKE MGW AND LBE...BUT THIS IS NOT EXPECTED TO CREATE ANY
RESTRICTIONS. ZZV COULD SEE SOME BREAKUP PAST 15Z THOUGH. WINDS
WILL REMAIN CALM OR VERY LIGHT.


OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
NEXT STORM SYSTEM WILL BEGIN TO IMPACT THE REGION ON TUESDAY AND
RESULT IN WIDESPREAD RAIN...CIG/VIS RESTRICTIONS...AND PERIODS OF
LLWS INTO THURSDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$






000
FXUS61 KPBZ 201733
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
1233 PM EST SAT DEC 20 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
SHORTWAVE TROUGH WILL SWING THROUGH THE OHIO VALLEY AND ACROSS THE
CWA DURING THE EARLY PART OF THE NIGHT. EXPECTING CLOUD COVER TO
BE MAINTAINED THROUGH THE PERIOD WITH AN OVERALL THIN BUT
PERSISTENT MOISTURE LAYER A COUPLE THOUSAND FEET UP.  WHILE
MOISTURE IS OTHERWISE FAIRLY MEAGER AT PRESENT...SW FLOW AT H850
WILL HELP PUSH MARGINALLY BETTER PWAT VALUES INTO THE SOUTHERN
COUNTIES BY SUNSET. THIS COMBINED WITH MODEST SUPPORT FROM SHORTWAVE MAY
ALLOW A FEW SNOWFLAKES TO SQUEEZE OUT...SO ADDED A SLIGHT CHANCE
POP TO THE GRIDS...MAINLY FOR THE EVENING...GENERALLY SOUTH OF A
HLG/PIT/IDI LINE. ANY ACTIVITY SHOULD END SOON AFTER 06Z WITH
SHORTWAVE DEPARTURE. TEMPERATURE FORECAST LOOKS DECENT OVERALL AT
THIS TIME.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY/...
MODELS ARE SHOWING SOME IMPROVEMENT SUNDAY...PARTICULARLY OVER
THE WEST AND FAR SOUTH. HOWEVER...MODEL SOUNDINGS FOR THE REST OF
THE REGION STILL WANT TO MAINTAIN A SATURATED LAYER AROUND 2500FT
FOR MOST OF THE DAY...WHICH DOES NOT PRESENT MUCH HOPE FOR
SUNSHINE. CLOUDS WILL BE TRICKY ON SUNDAY...TRYING TO DETERMINE
HOW MUCH OF THE CLOUD DECK WILL BE ERODED.

SPLIT FLOW DEVELOPS ON MONDAY WITH A LARGE SYSTEM TO THE WEST AND
ANOTHER SYSTEM TO THE SOUTH-SOUTHEAST. IT APPEARS THAT THE AREA
WILL LIE IN BETWEEN LIMITING THE CHANCES FOR PRECIPITATION. WAA
WILL CONTINUE ON MONDAY AND LOW-LEVEL MOISTURE INCREASES ONCE
AGAIN. LOOKS LIKE A GOOD DEAL OF CLOUD COVER AGAIN MONDAY. A WEAK
AND UNORGANIZED SHORTWAVE TROUGH WILL SWING THROUGH MONDAY...
ALLOWING FOR THE POSSIBILITY OF SOME LIGHT PRECIP...MAINLY OVER
THE SOUTHERN RIDGES. THIS WILL NEED TO BE FINE TUNED AS THE WARMER
AIR ALOFT MAY OCCUR BEFORE SURFACE TEMPS RESPOND. CONFIDENCE IS
LOW THAT ANY PRECIP WILL OCCUR...SO FOR FORECAST WILL LEAVE OUT.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
STILL SEEING SOME MINOR DIFFERENCES IN MEDIUM RANGE MODEL
SOLUTIONS FOR MIDWEEK SYSTEM. THINK MUCH OF TUESDAY COULD BE DRY
OR JUST LIGHT SHOWERS AS AREA WILL BE WELL INTO THE WARM SECTOR. RAIN
WILL OVERSPREAD THE AREA TUESDAY NIGHT AHEAD OF OCCLUDED FRONT AND
CONTINUE THROUGH WEDNESDAY. COLDER AIR WILL MOVE IN LATER
WEDNESDAY NIGHT CHANGING ANY LINGERING SHOWERS TO SNOW SHOWERS.
COULD SEE A BRIEF UPTICK IN SNOW SHOWER COVERAGE EARLY THURSDAY
MORNING AS MAIN TROUGH SWINGS THROUGH. COLD AIR WILL BE IN PLACE
THURSDAY...BUT WIND DIRECTION NOT OPTIMAL FOR LAKE INFLUENCED SNOW
SHOWERS.

WARMER AIR WILL MOVE BACK IN THURSDAY NIGHT AND FRIDAY.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
CLOUDS HAVE MANAGED TO THIN SOMEWHAT ACROSS SOUTHERN PA/NORTHERN
WV AND EXPECT THIS TO PERSIST FOR A FEW HOURS. HOWEVER...SW FLOW
WILL BRING A BIT MORE MOISTURE ALOFT...AS WELL AS WARM
ADVECTION...WHICH WILL HELP TO SHARPEN UP THE INVERSION ALOFT.
THUS...EXPECTING MOST AREAS TO SEE MVFR CIGS BECOME REESTABLISHED
BY THE LATE EVENING HOURS...AND PERSIST THROUGH THE REST OF THE
TAF PERIOD. CANNOT RULE OUT A FEW SNOWFLAKES TONIGHT IN LOCATIONS
LIKE MGW AND LBE...BUT THIS IS NOT EXPECTED TO CREATE ANY
RESTRICTIONS. ZZV COULD SEE SOME BREAKUP PAST 15Z THOUGH. WINDS
WILL REMAIN CALM OR VERY LIGHT.


OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
NEXT STORM SYSTEM WILL BEGIN TO IMPACT THE REGION ON TUESDAY AND
RESULT IN WIDESPREAD RAIN...CIG/VIS RESTRICTIONS...AND PERIODS OF
LLWS INTO THURSDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$






000
FXUS61 KPBZ 201733
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
1233 PM EST SAT DEC 20 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
SHORTWAVE TROUGH WILL SWING THROUGH THE OHIO VALLEY AND ACROSS THE
CWA DURING THE EARLY PART OF THE NIGHT. EXPECTING CLOUD COVER TO
BE MAINTAINED THROUGH THE PERIOD WITH AN OVERALL THIN BUT
PERSISTENT MOISTURE LAYER A COUPLE THOUSAND FEET UP.  WHILE
MOISTURE IS OTHERWISE FAIRLY MEAGER AT PRESENT...SW FLOW AT H850
WILL HELP PUSH MARGINALLY BETTER PWAT VALUES INTO THE SOUTHERN
COUNTIES BY SUNSET. THIS COMBINED WITH MODEST SUPPORT FROM SHORTWAVE MAY
ALLOW A FEW SNOWFLAKES TO SQUEEZE OUT...SO ADDED A SLIGHT CHANCE
POP TO THE GRIDS...MAINLY FOR THE EVENING...GENERALLY SOUTH OF A
HLG/PIT/IDI LINE. ANY ACTIVITY SHOULD END SOON AFTER 06Z WITH
SHORTWAVE DEPARTURE. TEMPERATURE FORECAST LOOKS DECENT OVERALL AT
THIS TIME.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY/...
MODELS ARE SHOWING SOME IMPROVEMENT SUNDAY...PARTICULARLY OVER
THE WEST AND FAR SOUTH. HOWEVER...MODEL SOUNDINGS FOR THE REST OF
THE REGION STILL WANT TO MAINTAIN A SATURATED LAYER AROUND 2500FT
FOR MOST OF THE DAY...WHICH DOES NOT PRESENT MUCH HOPE FOR
SUNSHINE. CLOUDS WILL BE TRICKY ON SUNDAY...TRYING TO DETERMINE
HOW MUCH OF THE CLOUD DECK WILL BE ERODED.

SPLIT FLOW DEVELOPS ON MONDAY WITH A LARGE SYSTEM TO THE WEST AND
ANOTHER SYSTEM TO THE SOUTH-SOUTHEAST. IT APPEARS THAT THE AREA
WILL LIE IN BETWEEN LIMITING THE CHANCES FOR PRECIPITATION. WAA
WILL CONTINUE ON MONDAY AND LOW-LEVEL MOISTURE INCREASES ONCE
AGAIN. LOOKS LIKE A GOOD DEAL OF CLOUD COVER AGAIN MONDAY. A WEAK
AND UNORGANIZED SHORTWAVE TROUGH WILL SWING THROUGH MONDAY...
ALLOWING FOR THE POSSIBILITY OF SOME LIGHT PRECIP...MAINLY OVER
THE SOUTHERN RIDGES. THIS WILL NEED TO BE FINE TUNED AS THE WARMER
AIR ALOFT MAY OCCUR BEFORE SURFACE TEMPS RESPOND. CONFIDENCE IS
LOW THAT ANY PRECIP WILL OCCUR...SO FOR FORECAST WILL LEAVE OUT.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
STILL SEEING SOME MINOR DIFFERENCES IN MEDIUM RANGE MODEL
SOLUTIONS FOR MIDWEEK SYSTEM. THINK MUCH OF TUESDAY COULD BE DRY
OR JUST LIGHT SHOWERS AS AREA WILL BE WELL INTO THE WARM SECTOR. RAIN
WILL OVERSPREAD THE AREA TUESDAY NIGHT AHEAD OF OCCLUDED FRONT AND
CONTINUE THROUGH WEDNESDAY. COLDER AIR WILL MOVE IN LATER
WEDNESDAY NIGHT CHANGING ANY LINGERING SHOWERS TO SNOW SHOWERS.
COULD SEE A BRIEF UPTICK IN SNOW SHOWER COVERAGE EARLY THURSDAY
MORNING AS MAIN TROUGH SWINGS THROUGH. COLD AIR WILL BE IN PLACE
THURSDAY...BUT WIND DIRECTION NOT OPTIMAL FOR LAKE INFLUENCED SNOW
SHOWERS.

WARMER AIR WILL MOVE BACK IN THURSDAY NIGHT AND FRIDAY.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
CLOUDS HAVE MANAGED TO THIN SOMEWHAT ACROSS SOUTHERN PA/NORTHERN
WV AND EXPECT THIS TO PERSIST FOR A FEW HOURS. HOWEVER...SW FLOW
WILL BRING A BIT MORE MOISTURE ALOFT...AS WELL AS WARM
ADVECTION...WHICH WILL HELP TO SHARPEN UP THE INVERSION ALOFT.
THUS...EXPECTING MOST AREAS TO SEE MVFR CIGS BECOME REESTABLISHED
BY THE LATE EVENING HOURS...AND PERSIST THROUGH THE REST OF THE
TAF PERIOD. CANNOT RULE OUT A FEW SNOWFLAKES TONIGHT IN LOCATIONS
LIKE MGW AND LBE...BUT THIS IS NOT EXPECTED TO CREATE ANY
RESTRICTIONS. ZZV COULD SEE SOME BREAKUP PAST 15Z THOUGH. WINDS
WILL REMAIN CALM OR VERY LIGHT.


OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
NEXT STORM SYSTEM WILL BEGIN TO IMPACT THE REGION ON TUESDAY AND
RESULT IN WIDESPREAD RAIN...CIG/VIS RESTRICTIONS...AND PERIODS OF
LLWS INTO THURSDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$






000
FXUS61 KPHI 201548
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1048 AM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER SOUTHWESTERN QUEBEC THIS MORNING WILL
DRIFT EASTWARD AND IT SHOULD REACH ATLANTIC CANADA ON MONDAY. WEAK
LOW PRESSURE IS FORECAST TO DEVELOP OFF THE CAROLINA COAST ON
MONDAY BEFORE MOVING SLOWLY NORTHEASTWARD AND DISSIPATING. STRONG
LOW PRESSURE IS EXPECTED TO LIFT NORTHWARD FROM THE LOWER
MISSISSIPPI RIVER VALLEY AND ACROSS THE GREAT LAKES DURING THE MID
WEEK PERIOD. THE LOW IS ANTICIPATED TO PULL A WARM FRONT THROUGH
OUR REGION ON WEDNESDAY, FOLLOWED BY A COLD FRONT ON WEDNESDAY
NIGHT. HIGH PRESSURE IS EXPECTED TO FOLLOW FROM THE SOUTHWEST FOR
THURSDAY AND FRIDAY. ANOTHER COLD FRONT IS FORECAST TO APPROACH
FROM THE WEST AND IT MAY ARRIVE ON SATURDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WE HAVE RECEIVED A FEW CALLS ABOUT SOME LIGHT SNOW ACROSS THE
NORTHERN AREAS. MUCH OF THE ACTIVITY IS LIGHT AND FALLING BELOW
THE RADAR BEAM. WE HAVE ADDED SOME CHC POPS TO THE FCST ACROSS THE
SRN POCONOS AND SUSSEX COUNTY NJ. OTHER THAN THAT...FEW CHANGES
WERE NEEDED TO THE EARLIER FCST. TEMPS AND DEW POINTS WERE NOT
CHANGED AND WINDS ONLY HAD SOME SLIGHT ADJUSTMENTS. PUBLIC
PRODUCTS HAVE BEEN UPDATED.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/...
NOT MUCH OF A CHANGE TO THE FORECAST TONIGHT FROM THE DAY TIME.
HIGH PRESSURE, CENTERED ACROSS NORTHERN NEW ENGLAND AND EASTERN
CANADA REMAINS IN CONTROL OF THE WEATHER. WITH CONTINUING LOW PW
VALUES, NO PRECIPITATION IS EXPECTED. CLOUD COVER SHOULD REMAIN
ACROSS THE AREA, ESPECIALLY AS A SHORT WAVE/VORTICITY MAX SLIDES
TOWARD THE AREA OVERNIGHT.

OVERNIGHT LOWS WERE A BLEND OF MAV/MET MOS AND MOSGUIDE WHICH
WERE IN PRETTY GOOD AGREEMENT.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
A MID LEVEL SHORT WAVE THAT WAS LOCATED OVER WESTERN IOWA AND
VICINITY EARLY THIS MORNING WILL PROGRESS EASTWARD AND IT SHOULD
PASS OVER OUR REGION EARLY ON SUNDAY MORNING. WHILE WE ARE
ANTICIPATING SOME CLOUDS WITH THE SYSTEM THERE SHOULD NOT BE
ENOUGH MOISTURE TO PRODUCE ANY PRECIPITATION.

SURFACE HIGH PRESSURE IS FORECAST TO BE LOCATED OVER SOUTHERN
QUEBEC ON SUNDAY MORNING. THE CENTER OF THE HIGH SHOULD DRIFT
EASTWARD REACHING ATLANTIC CANADA ON MONDAY AND MONDAY NIGHT. A
RIDGE AXIS IS EXPECTED TO NOSE SOUTHWESTWARD ALONG THE LEE OF THE
APPALACHIANS AT THAT TIME WITH AN INVERTED TROUGH DEVELOPING OFF
THE COAST. WEAK LOW PRESSURE IS ANTICIPATED TO DEVELOP ON THE
TROUGH OFF THE CAROLINA COAST ON MONDAY. THE FEATURE IS FORECAST
TO REMAIN WEAK AS IT DRIFTS NORTHEASTWARD REACHING THE WATERS OFF
THE DELMARVA BEFORE DISSIPATING ON TUESDAY.

AREAS OF LIGHT PRECIPITATION ARE EXPECTED TO SPREAD SLOWLY
NORTHWARD INTO OUR REGION ON MONDAY AND THEY SHOULD REMAIN HERE
FOR MONDAY NIGHT AND TUESDAY. THE OVERALL TREND WILL BE TOWARD
WARMING TEMPERATURES. AS A RESULT, MOST OF THE PRECIPITATION IS
ANTICIPATED TO BE IN THE FORM OF RAIN. HOWEVER, POCKETS OF BELOW
FREEZING TEMPERATURES MAY LINGER IN THE POCONOS ON MONDAY NIGHT
INTO EARLY TUESDAY MORNING SO WE HAVE MENTIONED A CHANCE OF
FREEZING RAIN THERE.

OUR MAIN WEATHER FEATURE FOR THE COMING WEEK IS THE DEEP MID
LEVEL TROUGH THAT IS FORECAST TO DIG OVER THE MIDDLE PART OF THE
COUNTRY ON MONDAY AND TUESDAY. THE TROUGH IS EXPECTED TO LIFT
NORTHEASTWARD AND ITS AXIS SHOULD PASS OVERHEAD EARLY ON THURSDAY.

SURFACE LOW PRESSURE IS ANTICIPATED TO DEVELOP OVER THE LOWER
MISSISSIPPI RIVER VALLEY ON TUESDAY IN RESPONSE TO THE TROUGH. THE
LOW IS FORECAST TO STRENGTHEN AS IT MOVES ACROSS THE GREAT LAKES
ON WEDNESDAY AND WEDNESDAY NIGHT. THE SYSTEM SHOULD HAVE AN
OPPORTUNITY TO TAP INTO GULF MOISTURE AND IT WILL BRING THE
POTENTIAL FOR SOME MODERATE TO HEAVY RAINFALL TO OUR REGION FROM
WEDNESDAY INTO EARLY WEDNESDAY NIGHT.

THE LOW IS EXPECTED TO PULL A WARM FRONT THROUGH OUR REGION ON
WEDNESDAY WITH TEMPERATURES FORECAST TO RISE INTO THE 50S AT MOST
LOCATIONS. SOME 60 DEGREE READINGS ARE POSSIBLE ON THE DELMARVA
AND PERHAPS IN FAR SOUTHERN NEW JERSEY. CONDITIONS MAY BECOME
QUITE BREEZY IN THE WARM SECTOR WHERE THE ATMOSPHERE SHOULD MIX
RATHER EFFICIENTLY. A STRONG COLD FRONT IS FORECAST TO FOLLOW ON
WEDNESDAY NIGHT WITH TEMPERATURES DROPPING BACK INTO THE 30S BY
DAYBREAK ON THURSDAY. THE PROBABILITY OF PRECIPITATION DECREASES
RAPIDLY ON WEDNESDAY NIGHT AS DRY AIR IS EXPECTED TO BUILD INTO
OUR REGION FROM THE SOUTHWEST.

RIDGING IS FORECAST TO DEVELOP AT THE SURFACE AND ALOFT FOR
THURSDAY INTO FRIDAY WITH MAINLY DRY WEATHER AND SEASONABLE
TEMPERATURES ANTICIPATED.

A MID LEVEL SHORT WAVE MAY APPROACH FROM THE WEST ON SATURDAY
ALONG WITH AN ASSOCIATED SURFACE COLD FRONT. THE GUIDANCE DIFFERS
A BIT ON THE TIMING OF THE FEATURE AT THIS POINT AS WELL ON THE
AMOUNT OF MOISTURE ASSOCIATED WITH THE SYSTEM.

&&

.AVIATION /16Z SATURDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

MOST OF THE TAF SITES ARE NOW MVFR, EXCEPT PHL/ILG/MIV, ALTHOUGH
THEY SHOULD BE THERE SHORTLY. THE MVFR CIGS WILL CONTINUE ACROSS
THE TAF SITES THROUGH THIS MORNING AS MOISTURE REMAINS TRAPPED
UNDERNEATH THE INVERSION. CLOUDS MAY SCATTER OUT DURING THE DAY
WITH HIGHER LEVEL CLOUDS OVERHEAD, LEADING TO VFR CONDITIONS FOR
THE REMAINDER OF THE PERIOD. IF THE CLOUDS DO NOT BEGIN TO SCATTER
OUT BY MIDDAY, IT`S POSSIBLE WE COULD SEE AN EXTENDED PERIOD OF
MVFR CIGS THROUGH THE DAY INTO TONIGHT.

NORTHERLY WINDS WILL BE LIGHT, GENERALLY AROUND 5-10 KNOTS OR
LESS THROUGH THE DAY. SOME NORTHWEST TO WEST WINDS ARE POSSIBLE
EARLY, BUT SHOULD BECOME MORE NORTHERLY DURING THE DAY. EVERYONE
IS EXPECTED TO BECOME LIGHT AND VARIABLE/CALM LATER THIS AFTERNOON
INTO THE EVENING/OVERNIGHT.

OUTLOOK...
SUNDAY AND SUNDAY NIGHT...MAINLY VFR.

MONDAY...MAINLY VFR WITH A CHANCE OF LIGHT RAIN SPREADING
NORTHWARD INTO OUR REGION.

MONDAY NIGHT AND TUESDAY...CONDITIONS POSSIBLY LOWERING INTO THE
MVFR CATEGORY WITH A CHANCE OF LIGHT RAIN.

TUESDAY NIGHT...MVFR AND IFR CONDITIONS ANTICIPATED WITH RAIN
LIKELY.

WEDNESDAY...MVFR AND IFR CONDITIONS WITH RAIN LIKELY. THE RAIN
MAY BE HEAVY AT TIMES. A GUSTY SOUTH WIND MAY DEVELOP, ESPECIALLY
IN THE AFTERNOON.

&&

.MARINE...
SUB-SMALL CRAFT ADVISORY CONDITIONS WILL REMAIN TODAY INTO
TONIGHT AS HIGH PRESSURE FROM THE NORTH WILL AFFECT THE WATERS.

OUTLOOK...
SUNDAY THROUGH MONDAY NIGHT...NO MARINE HEADLINES ARE
ANTICIPATED.

TUESDAY AND TUESDAY NIGHT...WAVE HEIGHTS ON OUR OCEAN WATERS MAY
BUILD TO 5 TO 6 FEET IN A DEVELOPING ONSHORE FLOW.

WEDNESDAY...SOUTHERLY WIND GUSTS IN EXCESS OF 25 KNOTS ARE
EXPECTED. WAVE HEIGHTS ON OUR OCEAN WATERS MAY BUILD TO 6 TO 9
FEET IN A STRONG SOUTHERLY FLOW.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...IOVINO
NEAR TERM...OHARA
SHORT TERM...ROBERTSON
LONG TERM...IOVINO
AVIATION...IOVINO/ROBERTSON
MARINE...IOVINO/ROBERTSON







000
FXUS61 KPHI 201548
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1048 AM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER SOUTHWESTERN QUEBEC THIS MORNING WILL
DRIFT EASTWARD AND IT SHOULD REACH ATLANTIC CANADA ON MONDAY. WEAK
LOW PRESSURE IS FORECAST TO DEVELOP OFF THE CAROLINA COAST ON
MONDAY BEFORE MOVING SLOWLY NORTHEASTWARD AND DISSIPATING. STRONG
LOW PRESSURE IS EXPECTED TO LIFT NORTHWARD FROM THE LOWER
MISSISSIPPI RIVER VALLEY AND ACROSS THE GREAT LAKES DURING THE MID
WEEK PERIOD. THE LOW IS ANTICIPATED TO PULL A WARM FRONT THROUGH
OUR REGION ON WEDNESDAY, FOLLOWED BY A COLD FRONT ON WEDNESDAY
NIGHT. HIGH PRESSURE IS EXPECTED TO FOLLOW FROM THE SOUTHWEST FOR
THURSDAY AND FRIDAY. ANOTHER COLD FRONT IS FORECAST TO APPROACH
FROM THE WEST AND IT MAY ARRIVE ON SATURDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WE HAVE RECEIVED A FEW CALLS ABOUT SOME LIGHT SNOW ACROSS THE
NORTHERN AREAS. MUCH OF THE ACTIVITY IS LIGHT AND FALLING BELOW
THE RADAR BEAM. WE HAVE ADDED SOME CHC POPS TO THE FCST ACROSS THE
SRN POCONOS AND SUSSEX COUNTY NJ. OTHER THAN THAT...FEW CHANGES
WERE NEEDED TO THE EARLIER FCST. TEMPS AND DEW POINTS WERE NOT
CHANGED AND WINDS ONLY HAD SOME SLIGHT ADJUSTMENTS. PUBLIC
PRODUCTS HAVE BEEN UPDATED.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/...
NOT MUCH OF A CHANGE TO THE FORECAST TONIGHT FROM THE DAY TIME.
HIGH PRESSURE, CENTERED ACROSS NORTHERN NEW ENGLAND AND EASTERN
CANADA REMAINS IN CONTROL OF THE WEATHER. WITH CONTINUING LOW PW
VALUES, NO PRECIPITATION IS EXPECTED. CLOUD COVER SHOULD REMAIN
ACROSS THE AREA, ESPECIALLY AS A SHORT WAVE/VORTICITY MAX SLIDES
TOWARD THE AREA OVERNIGHT.

OVERNIGHT LOWS WERE A BLEND OF MAV/MET MOS AND MOSGUIDE WHICH
WERE IN PRETTY GOOD AGREEMENT.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
A MID LEVEL SHORT WAVE THAT WAS LOCATED OVER WESTERN IOWA AND
VICINITY EARLY THIS MORNING WILL PROGRESS EASTWARD AND IT SHOULD
PASS OVER OUR REGION EARLY ON SUNDAY MORNING. WHILE WE ARE
ANTICIPATING SOME CLOUDS WITH THE SYSTEM THERE SHOULD NOT BE
ENOUGH MOISTURE TO PRODUCE ANY PRECIPITATION.

SURFACE HIGH PRESSURE IS FORECAST TO BE LOCATED OVER SOUTHERN
QUEBEC ON SUNDAY MORNING. THE CENTER OF THE HIGH SHOULD DRIFT
EASTWARD REACHING ATLANTIC CANADA ON MONDAY AND MONDAY NIGHT. A
RIDGE AXIS IS EXPECTED TO NOSE SOUTHWESTWARD ALONG THE LEE OF THE
APPALACHIANS AT THAT TIME WITH AN INVERTED TROUGH DEVELOPING OFF
THE COAST. WEAK LOW PRESSURE IS ANTICIPATED TO DEVELOP ON THE
TROUGH OFF THE CAROLINA COAST ON MONDAY. THE FEATURE IS FORECAST
TO REMAIN WEAK AS IT DRIFTS NORTHEASTWARD REACHING THE WATERS OFF
THE DELMARVA BEFORE DISSIPATING ON TUESDAY.

AREAS OF LIGHT PRECIPITATION ARE EXPECTED TO SPREAD SLOWLY
NORTHWARD INTO OUR REGION ON MONDAY AND THEY SHOULD REMAIN HERE
FOR MONDAY NIGHT AND TUESDAY. THE OVERALL TREND WILL BE TOWARD
WARMING TEMPERATURES. AS A RESULT, MOST OF THE PRECIPITATION IS
ANTICIPATED TO BE IN THE FORM OF RAIN. HOWEVER, POCKETS OF BELOW
FREEZING TEMPERATURES MAY LINGER IN THE POCONOS ON MONDAY NIGHT
INTO EARLY TUESDAY MORNING SO WE HAVE MENTIONED A CHANCE OF
FREEZING RAIN THERE.

OUR MAIN WEATHER FEATURE FOR THE COMING WEEK IS THE DEEP MID
LEVEL TROUGH THAT IS FORECAST TO DIG OVER THE MIDDLE PART OF THE
COUNTRY ON MONDAY AND TUESDAY. THE TROUGH IS EXPECTED TO LIFT
NORTHEASTWARD AND ITS AXIS SHOULD PASS OVERHEAD EARLY ON THURSDAY.

SURFACE LOW PRESSURE IS ANTICIPATED TO DEVELOP OVER THE LOWER
MISSISSIPPI RIVER VALLEY ON TUESDAY IN RESPONSE TO THE TROUGH. THE
LOW IS FORECAST TO STRENGTHEN AS IT MOVES ACROSS THE GREAT LAKES
ON WEDNESDAY AND WEDNESDAY NIGHT. THE SYSTEM SHOULD HAVE AN
OPPORTUNITY TO TAP INTO GULF MOISTURE AND IT WILL BRING THE
POTENTIAL FOR SOME MODERATE TO HEAVY RAINFALL TO OUR REGION FROM
WEDNESDAY INTO EARLY WEDNESDAY NIGHT.

THE LOW IS EXPECTED TO PULL A WARM FRONT THROUGH OUR REGION ON
WEDNESDAY WITH TEMPERATURES FORECAST TO RISE INTO THE 50S AT MOST
LOCATIONS. SOME 60 DEGREE READINGS ARE POSSIBLE ON THE DELMARVA
AND PERHAPS IN FAR SOUTHERN NEW JERSEY. CONDITIONS MAY BECOME
QUITE BREEZY IN THE WARM SECTOR WHERE THE ATMOSPHERE SHOULD MIX
RATHER EFFICIENTLY. A STRONG COLD FRONT IS FORECAST TO FOLLOW ON
WEDNESDAY NIGHT WITH TEMPERATURES DROPPING BACK INTO THE 30S BY
DAYBREAK ON THURSDAY. THE PROBABILITY OF PRECIPITATION DECREASES
RAPIDLY ON WEDNESDAY NIGHT AS DRY AIR IS EXPECTED TO BUILD INTO
OUR REGION FROM THE SOUTHWEST.

RIDGING IS FORECAST TO DEVELOP AT THE SURFACE AND ALOFT FOR
THURSDAY INTO FRIDAY WITH MAINLY DRY WEATHER AND SEASONABLE
TEMPERATURES ANTICIPATED.

A MID LEVEL SHORT WAVE MAY APPROACH FROM THE WEST ON SATURDAY
ALONG WITH AN ASSOCIATED SURFACE COLD FRONT. THE GUIDANCE DIFFERS
A BIT ON THE TIMING OF THE FEATURE AT THIS POINT AS WELL ON THE
AMOUNT OF MOISTURE ASSOCIATED WITH THE SYSTEM.

&&

.AVIATION /16Z SATURDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

MOST OF THE TAF SITES ARE NOW MVFR, EXCEPT PHL/ILG/MIV, ALTHOUGH
THEY SHOULD BE THERE SHORTLY. THE MVFR CIGS WILL CONTINUE ACROSS
THE TAF SITES THROUGH THIS MORNING AS MOISTURE REMAINS TRAPPED
UNDERNEATH THE INVERSION. CLOUDS MAY SCATTER OUT DURING THE DAY
WITH HIGHER LEVEL CLOUDS OVERHEAD, LEADING TO VFR CONDITIONS FOR
THE REMAINDER OF THE PERIOD. IF THE CLOUDS DO NOT BEGIN TO SCATTER
OUT BY MIDDAY, IT`S POSSIBLE WE COULD SEE AN EXTENDED PERIOD OF
MVFR CIGS THROUGH THE DAY INTO TONIGHT.

NORTHERLY WINDS WILL BE LIGHT, GENERALLY AROUND 5-10 KNOTS OR
LESS THROUGH THE DAY. SOME NORTHWEST TO WEST WINDS ARE POSSIBLE
EARLY, BUT SHOULD BECOME MORE NORTHERLY DURING THE DAY. EVERYONE
IS EXPECTED TO BECOME LIGHT AND VARIABLE/CALM LATER THIS AFTERNOON
INTO THE EVENING/OVERNIGHT.

OUTLOOK...
SUNDAY AND SUNDAY NIGHT...MAINLY VFR.

MONDAY...MAINLY VFR WITH A CHANCE OF LIGHT RAIN SPREADING
NORTHWARD INTO OUR REGION.

MONDAY NIGHT AND TUESDAY...CONDITIONS POSSIBLY LOWERING INTO THE
MVFR CATEGORY WITH A CHANCE OF LIGHT RAIN.

TUESDAY NIGHT...MVFR AND IFR CONDITIONS ANTICIPATED WITH RAIN
LIKELY.

WEDNESDAY...MVFR AND IFR CONDITIONS WITH RAIN LIKELY. THE RAIN
MAY BE HEAVY AT TIMES. A GUSTY SOUTH WIND MAY DEVELOP, ESPECIALLY
IN THE AFTERNOON.

&&

.MARINE...
SUB-SMALL CRAFT ADVISORY CONDITIONS WILL REMAIN TODAY INTO
TONIGHT AS HIGH PRESSURE FROM THE NORTH WILL AFFECT THE WATERS.

OUTLOOK...
SUNDAY THROUGH MONDAY NIGHT...NO MARINE HEADLINES ARE
ANTICIPATED.

TUESDAY AND TUESDAY NIGHT...WAVE HEIGHTS ON OUR OCEAN WATERS MAY
BUILD TO 5 TO 6 FEET IN A DEVELOPING ONSHORE FLOW.

WEDNESDAY...SOUTHERLY WIND GUSTS IN EXCESS OF 25 KNOTS ARE
EXPECTED. WAVE HEIGHTS ON OUR OCEAN WATERS MAY BUILD TO 6 TO 9
FEET IN A STRONG SOUTHERLY FLOW.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...IOVINO
NEAR TERM...OHARA
SHORT TERM...ROBERTSON
LONG TERM...IOVINO
AVIATION...IOVINO/ROBERTSON
MARINE...IOVINO/ROBERTSON






000
FXUS61 KCTP 201518
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1018 AM EST SAT DEC 20 2014

.SYNOPSIS...
A HIGH PRESSURE AREA CENTERED OVER THE GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND. A DEEP UPPER TROUGH AND
ASSOCIATED SFC LOW WILL LIFT NORTHEAST THROUGH THE GREAT LAKES
DURING THE MIDDLE OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SUBSIDENCE INVERSION MAINTAINING THE GLOOMY SKIES THIS MORNING...
WHILE DECAYING MID-UPPER CLOUD FROM UNDERCUTTING SHORTWAVE SOUTH
OF THE MASON DIXON LINE IS LIFTING ACROSS SOUTHWEST AND CENTRAL
AREAS. LITTLE IF ANY SUNSHINE WILL BE SEEN FOR YET ANOTHER
DAY. THIS AND LOW DECEMBER SUN ANGLE WILL RESULT IN HIGHS ONLY
IN THE LOW TO MID 30S MOST PLACES.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
NEXT SHORTWAVE...OVR IOWA AT 09Z...WILL TRACK ACROSS THE REGION
TONIGHT. THIS MOISTURE-STARVED FEATURE SHOULD PRODUCE PLENTY OF
MID LVL CLOUDINESS TONIGHT...BUT PROBABLY NO PRECIP DUE TO DRY AIR
IN THE 0-3KM LAYER. STILL...CAN/T RULE OUT A FLURRY IN SPOTS.

IN WAKE OF TONIGHT/S SHORTWAVE...A GOOD DEAL OF SUNSHINE IS
EXPECTED SUNDAY UNDER RIDGING AT SFC AND ALOFT. CONSALL OUTPUT
SUGGESTS MAX TEMPS WILL RANGE FROM THE 30S MOST PLACES...TO THE
L40S ACROSS THE LOWER SUSQ VALLEY.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
INCREASINGLY MOIST SERLY FLOW WILL DEVELOP OFF THE ATLANTIC EARLY
NEXT WEEK IN GRADIENT BTWN RETREATING HIGH OVR NEW ENG AND WEAK
LOW RIDING UP THE E COAST. THE INFLUX OF LOW LVL MOISTURE...COMBINED
WITH OROGRAPHIC LIFT...WILL LIKELY YIELD DAMP AND DRIZZLY WX MON
NITE THROUGH TUESDAY. MDLS HINT AT PERHAPS JUST ENOUGH LOW LVL
COLD AIR FOR AN INITIAL PERIOD OF -FZRA/FZDZ OVR THE HIGHER
TERRAIN OF THE APPALACHIANS MON NITE.

MED RANGE GUIDANCE HAS CONVERGED ON TIMING/TRACK OF DEEP TROUGH
AND ASSOC SFC LOW DURING MID WEEK...ALL OF WHICH POINTS TOWARD A
MILD AND RAINY CHRISTMAS EVE IN WARM SECTOR OF THIS SYSTEM. BLEND
OF MED RANGE GUIDANCE SUPPORTS ARND 1 INCH OF RAIN...FALLING
MOSTLY WITH PASSAGE OF LL JET/PLUME OF ANOMALOUS PWATS WEDNESDAY.
SURGE OF VERY WARM AIR SHOULD PRECEDE THE TRAILING COLD FRONT...PUSHING
READINGS INTO THE 50S OVR MOST OF THE AREA WEDNESDAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS IS LIKELY WED NIGHT INTO THURSDAY OVR THE W MTNS...PERHAPS
BRINGING A WHITE XMAS TO THE ALLEGHENY PLATEAU. THE BIGGER STORY
MAY BE THE STRONG/GUSTY WINDS WED NITE/THURSDAY. DEEPENING SFC
LOWS TRACKING THRU THE E GRT LKS TYPICALLY BRING CENTRAL PA SOME
OF OUR STRONGEST WINDS AND LATEST GUIDANCE SUGGESTS WINDS COULD
BE NEAR ADVISORY CRITERIA ON CHRISTMAS.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
00Z ECENS AND GEFS SHOWING THE UPPER TROF QUICKLY LIFTING OUT BY
FRIDAY.

&&

.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
SHALLOW STRATOCU DECK REMAINS TRAPPED BENEATH SUBSIDENCE
INVERSION THIS MORNING...WITH MVFR CIGS.  LOWER CIGS WILL PERSIST
IN THE NORTHERN MTNS...WITH IMPROVING CIGS CENTRAL AND SOUTH. WINDS
WILL BE LIGHT FROM THE WEST.

CIG RESTRICTIONS IN EXPANDING STRATOCU DECK LIKELY RETURN AGAIN
TONIGHT...THOUGH LOW CLOUDS SHOULD NOT BE QUITE AS EXPANSIVE AS
PREVIOUS NIGHTS. A SHORTWAVE WILL TRACK ACROSS THE REGION BRINGING
A THICKENING MID-LVL DECK AS WELL. SURFACE WINDS WILL CONTINUE TO
BE LIGHT...WITH SW FLOW ALOFT BEGINNING TO INCREASE AS A LARGE LOW
PRESSURE SYSTEM BEGINS TO DEEPEN OVER THE CENTRAL U.S.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...DEVOIR/FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/EVANEGO
AVIATION...DEVOIR/RXR



000
FXUS61 KCTP 201518
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1018 AM EST SAT DEC 20 2014

.SYNOPSIS...
A HIGH PRESSURE AREA CENTERED OVER THE GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND. A DEEP UPPER TROUGH AND
ASSOCIATED SFC LOW WILL LIFT NORTHEAST THROUGH THE GREAT LAKES
DURING THE MIDDLE OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SUBSIDENCE INVERSION MAINTAINING THE GLOOMY SKIES THIS MORNING...
WHILE DECAYING MID-UPPER CLOUD FROM UNDERCUTTING SHORTWAVE SOUTH
OF THE MASON DIXON LINE IS LIFTING ACROSS SOUTHWEST AND CENTRAL
AREAS. LITTLE IF ANY SUNSHINE WILL BE SEEN FOR YET ANOTHER
DAY. THIS AND LOW DECEMBER SUN ANGLE WILL RESULT IN HIGHS ONLY
IN THE LOW TO MID 30S MOST PLACES.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
NEXT SHORTWAVE...OVR IOWA AT 09Z...WILL TRACK ACROSS THE REGION
TONIGHT. THIS MOISTURE-STARVED FEATURE SHOULD PRODUCE PLENTY OF
MID LVL CLOUDINESS TONIGHT...BUT PROBABLY NO PRECIP DUE TO DRY AIR
IN THE 0-3KM LAYER. STILL...CAN/T RULE OUT A FLURRY IN SPOTS.

IN WAKE OF TONIGHT/S SHORTWAVE...A GOOD DEAL OF SUNSHINE IS
EXPECTED SUNDAY UNDER RIDGING AT SFC AND ALOFT. CONSALL OUTPUT
SUGGESTS MAX TEMPS WILL RANGE FROM THE 30S MOST PLACES...TO THE
L40S ACROSS THE LOWER SUSQ VALLEY.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
INCREASINGLY MOIST SERLY FLOW WILL DEVELOP OFF THE ATLANTIC EARLY
NEXT WEEK IN GRADIENT BTWN RETREATING HIGH OVR NEW ENG AND WEAK
LOW RIDING UP THE E COAST. THE INFLUX OF LOW LVL MOISTURE...COMBINED
WITH OROGRAPHIC LIFT...WILL LIKELY YIELD DAMP AND DRIZZLY WX MON
NITE THROUGH TUESDAY. MDLS HINT AT PERHAPS JUST ENOUGH LOW LVL
COLD AIR FOR AN INITIAL PERIOD OF -FZRA/FZDZ OVR THE HIGHER
TERRAIN OF THE APPALACHIANS MON NITE.

MED RANGE GUIDANCE HAS CONVERGED ON TIMING/TRACK OF DEEP TROUGH
AND ASSOC SFC LOW DURING MID WEEK...ALL OF WHICH POINTS TOWARD A
MILD AND RAINY CHRISTMAS EVE IN WARM SECTOR OF THIS SYSTEM. BLEND
OF MED RANGE GUIDANCE SUPPORTS ARND 1 INCH OF RAIN...FALLING
MOSTLY WITH PASSAGE OF LL JET/PLUME OF ANOMALOUS PWATS WEDNESDAY.
SURGE OF VERY WARM AIR SHOULD PRECEDE THE TRAILING COLD FRONT...PUSHING
READINGS INTO THE 50S OVR MOST OF THE AREA WEDNESDAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS IS LIKELY WED NIGHT INTO THURSDAY OVR THE W MTNS...PERHAPS
BRINGING A WHITE XMAS TO THE ALLEGHENY PLATEAU. THE BIGGER STORY
MAY BE THE STRONG/GUSTY WINDS WED NITE/THURSDAY. DEEPENING SFC
LOWS TRACKING THRU THE E GRT LKS TYPICALLY BRING CENTRAL PA SOME
OF OUR STRONGEST WINDS AND LATEST GUIDANCE SUGGESTS WINDS COULD
BE NEAR ADVISORY CRITERIA ON CHRISTMAS.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
00Z ECENS AND GEFS SHOWING THE UPPER TROF QUICKLY LIFTING OUT BY
FRIDAY.

&&

.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
SHALLOW STRATOCU DECK REMAINS TRAPPED BENEATH SUBSIDENCE
INVERSION THIS MORNING...WITH MVFR CIGS.  LOWER CIGS WILL PERSIST
IN THE NORTHERN MTNS...WITH IMPROVING CIGS CENTRAL AND SOUTH. WINDS
WILL BE LIGHT FROM THE WEST.

CIG RESTRICTIONS IN EXPANDING STRATOCU DECK LIKELY RETURN AGAIN
TONIGHT...THOUGH LOW CLOUDS SHOULD NOT BE QUITE AS EXPANSIVE AS
PREVIOUS NIGHTS. A SHORTWAVE WILL TRACK ACROSS THE REGION BRINGING
A THICKENING MID-LVL DECK AS WELL. SURFACE WINDS WILL CONTINUE TO
BE LIGHT...WITH SW FLOW ALOFT BEGINNING TO INCREASE AS A LARGE LOW
PRESSURE SYSTEM BEGINS TO DEEPEN OVER THE CENTRAL U.S.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...DEVOIR/FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/EVANEGO
AVIATION...DEVOIR/RXR




000
FXUS61 KPBZ 201445
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
945 AM EST SAT DEC 20 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
SHORTWAVE TROUGH WILL SWING THROUGH THE OHIO VALLEY AND ACROSS THE
CWA DURING THE EARLY PART OF THE NIGHT. EXPECTING CLOUD COVER TO
BE MAINTAINED THROUGH THE PERIOD WITH AN OVERALL THIN BUT
PERSISTENT MOISTURE LAYER A COUPLE THOUSAND FEET UP.  WHILE
MOISTURE IS OTHERWISE FAIRLY MEAGER AT PRESENT...SW FLOW AT H850
WILL HELP PUSH MARGINALLY BETTER PWAT VALUES INTO THE SOUTHERN
COUNTIES BY SUNSET. THIS COMBINED WITH MODEST SUPPORT FROM SHORTWAVE MAY
ALLOW A FEW SNOWFLAKES TO SQUEEZE OUT...SO ADDED A SLIGHT CHANCE
POP TO THE GRIDS...MAINLY FOR THE EVENING...GENERALLY SOUTH OF A
HLG/PIT/IDI LINE. ANY ACTIVITY SHOULD END SOON AFTER 06Z WITH
SHORTWAVE DEPARTURE. TEMPERATURE FORECAST LOOKS DECENT OVERALL AT
THIS TIME.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY/...
MODELS ARE SHOWING SOME IMPROVEMENT SUNDAY...PARTICULARLY OVER
THE WEST AND FAR SOUTH. HOWEVER...MODEL SOUNDINGS FOR THE REST OF
THE REGION STILL WANT TO MAINTAIN A SATURATED LAYER AROUND 2500FT
FOR MOST OF THE DAY...WHICH DOES NOT PRESENT MUCH HOPE FOR
SUNSHINE. CLOUDS WILL BE TRICKY ON SUNDAY...TRYING TO DETERMINE
HOW MUCH OF THE CLOUD DECK WILL BE ERODED.

SPLIT FLOW DEVELOPS ON MONDAY WITH A LARGE SYSTEM TO THE WEST AND
ANOTHER SYSTEM TO THE SOUTH-SOUTHEAST. IT APPEARS THAT THE AREA
WILL LIE IN BETWEEN LIMITING THE CHANCES FOR PRECIPITATION. WAA
WILL CONTINUE ON MONDAY AND LOW-LEVEL MOISTURE INCREASES ONCE
AGAIN. LOOKS LIKE A GOOD DEAL OF CLOUD COVER AGAIN MONDAY. A WEAK
AND UNORGANIZED SHORTWAVE TROUGH WILL SWING THROUGH MONDAY...
ALLOWING FOR THE POSSIBILITY OF SOME LIGHT PRECIP...MAINLY OVER
THE SOUTHERN RIDGES. THIS WILL NEED TO BE FINE TUNED AS THE WARMER
AIR ALOFT MAY OCCUR BEFORE SURFACE TEMPS RESPOND. CONFIDENCE IS
LOW THAT ANY PRECIP WILL OCCUR...SO FOR FORECAST WILL LEAVE OUT.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
STILL SEEING SOME MINOR DIFFERENCES IN MEDIUM RANGE MODEL
SOLUTIONS FOR MIDWEEK SYSTEM. THINK MUCH OF TUESDAY COULD BE DRY
OR JUST LIGHT SHOWERS AS AREA WILL BE WELL INTO THE WARM SECTOR. RAIN
WILL OVERSPREAD THE AREA TUESDAY NIGHT AHEAD OF OCCLUDED FRONT AND
CONTINUE THROUGH WEDNESDAY. COLDER AIR WILL MOVE IN LATER
WEDNESDAY NIGHT CHANGING ANY LINGERING SHOWERS TO SNOW SHOWERS.
COULD SEE A BRIEF UPTICK IN SNOW SHOWER COVERAGE EARLY THURSDAY
MORNING AS MAIN TROUGH SWINGS THROUGH. COLD AIR WILL BE IN PLACE
THURSDAY...BUT WIND DIRECTION NOT OPTIMAL FOR LAKE INFLUENCED SNOW
SHOWERS.

WARMER AIR WILL MOVE BACK IN THURSDAY NIGHT AND FRIDAY.

&&

.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
LOW LEVEL MOISTURE WILL REMAIN TRAPPED UNDER A STRONG INVERSION
AOB 4KFT AS LOW LEVEL WINDS BECOME LIGHT....MAINTAINING HIGH MVFR
TO LOW VFR CONDITIONS OVER THE NEXT 24 HOURS. PRECIPITATION
CHANCES ARE MINIMAL GIVEN THE SHALLOW DEPTH OF THE SATURATED
LAYER AND ABSENCE OF ANY LIFT.

OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST THROUGH THE WEEKEND. NEXT STORM
SYSTEM WILL BEGIN TO IMPACT THE REGION ON TUESDAY AND RESULT IN
WIDESPREAD RAIN...CIG/VIS RESTRICTIONS...AND PERIODS OF LLWS
THROUGH WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$






000
FXUS61 KPBZ 201445
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
945 AM EST SAT DEC 20 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
SHORTWAVE TROUGH WILL SWING THROUGH THE OHIO VALLEY AND ACROSS THE
CWA DURING THE EARLY PART OF THE NIGHT. EXPECTING CLOUD COVER TO
BE MAINTAINED THROUGH THE PERIOD WITH AN OVERALL THIN BUT
PERSISTENT MOISTURE LAYER A COUPLE THOUSAND FEET UP.  WHILE
MOISTURE IS OTHERWISE FAIRLY MEAGER AT PRESENT...SW FLOW AT H850
WILL HELP PUSH MARGINALLY BETTER PWAT VALUES INTO THE SOUTHERN
COUNTIES BY SUNSET. THIS COMBINED WITH MODEST SUPPORT FROM SHORTWAVE MAY
ALLOW A FEW SNOWFLAKES TO SQUEEZE OUT...SO ADDED A SLIGHT CHANCE
POP TO THE GRIDS...MAINLY FOR THE EVENING...GENERALLY SOUTH OF A
HLG/PIT/IDI LINE. ANY ACTIVITY SHOULD END SOON AFTER 06Z WITH
SHORTWAVE DEPARTURE. TEMPERATURE FORECAST LOOKS DECENT OVERALL AT
THIS TIME.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY/...
MODELS ARE SHOWING SOME IMPROVEMENT SUNDAY...PARTICULARLY OVER
THE WEST AND FAR SOUTH. HOWEVER...MODEL SOUNDINGS FOR THE REST OF
THE REGION STILL WANT TO MAINTAIN A SATURATED LAYER AROUND 2500FT
FOR MOST OF THE DAY...WHICH DOES NOT PRESENT MUCH HOPE FOR
SUNSHINE. CLOUDS WILL BE TRICKY ON SUNDAY...TRYING TO DETERMINE
HOW MUCH OF THE CLOUD DECK WILL BE ERODED.

SPLIT FLOW DEVELOPS ON MONDAY WITH A LARGE SYSTEM TO THE WEST AND
ANOTHER SYSTEM TO THE SOUTH-SOUTHEAST. IT APPEARS THAT THE AREA
WILL LIE IN BETWEEN LIMITING THE CHANCES FOR PRECIPITATION. WAA
WILL CONTINUE ON MONDAY AND LOW-LEVEL MOISTURE INCREASES ONCE
AGAIN. LOOKS LIKE A GOOD DEAL OF CLOUD COVER AGAIN MONDAY. A WEAK
AND UNORGANIZED SHORTWAVE TROUGH WILL SWING THROUGH MONDAY...
ALLOWING FOR THE POSSIBILITY OF SOME LIGHT PRECIP...MAINLY OVER
THE SOUTHERN RIDGES. THIS WILL NEED TO BE FINE TUNED AS THE WARMER
AIR ALOFT MAY OCCUR BEFORE SURFACE TEMPS RESPOND. CONFIDENCE IS
LOW THAT ANY PRECIP WILL OCCUR...SO FOR FORECAST WILL LEAVE OUT.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
STILL SEEING SOME MINOR DIFFERENCES IN MEDIUM RANGE MODEL
SOLUTIONS FOR MIDWEEK SYSTEM. THINK MUCH OF TUESDAY COULD BE DRY
OR JUST LIGHT SHOWERS AS AREA WILL BE WELL INTO THE WARM SECTOR. RAIN
WILL OVERSPREAD THE AREA TUESDAY NIGHT AHEAD OF OCCLUDED FRONT AND
CONTINUE THROUGH WEDNESDAY. COLDER AIR WILL MOVE IN LATER
WEDNESDAY NIGHT CHANGING ANY LINGERING SHOWERS TO SNOW SHOWERS.
COULD SEE A BRIEF UPTICK IN SNOW SHOWER COVERAGE EARLY THURSDAY
MORNING AS MAIN TROUGH SWINGS THROUGH. COLD AIR WILL BE IN PLACE
THURSDAY...BUT WIND DIRECTION NOT OPTIMAL FOR LAKE INFLUENCED SNOW
SHOWERS.

WARMER AIR WILL MOVE BACK IN THURSDAY NIGHT AND FRIDAY.

&&

.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
LOW LEVEL MOISTURE WILL REMAIN TRAPPED UNDER A STRONG INVERSION
AOB 4KFT AS LOW LEVEL WINDS BECOME LIGHT....MAINTAINING HIGH MVFR
TO LOW VFR CONDITIONS OVER THE NEXT 24 HOURS. PRECIPITATION
CHANCES ARE MINIMAL GIVEN THE SHALLOW DEPTH OF THE SATURATED
LAYER AND ABSENCE OF ANY LIFT.

OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST THROUGH THE WEEKEND. NEXT STORM
SYSTEM WILL BEGIN TO IMPACT THE REGION ON TUESDAY AND RESULT IN
WIDESPREAD RAIN...CIG/VIS RESTRICTIONS...AND PERIODS OF LLWS
THROUGH WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$







000
FXUS61 KPBZ 201154
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
654 AM EST SAT DEC 20 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...

THE CURRENT FORECAST LOOKS TO BE IN GOOD SHAPE. NO UPDATES WILL BE
NEEDED EARLY THIS MORNING. PREV DISCUSSION FOLLOWS..

WEAK RIDGE BREAKS DOWN
LATER TODAY AS SHORTWAVE TROUGH WILL MOVE THROUGH THE UPPER
MIDWEST. WEAK CAA IS EXPECTED WITH THIS FEATURE WHICH WILL HELP TO
MAINTAIN CLOUD COVER.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
SHORTWAVE TROUGH WILL SWING THROUGH TONIGHT. PRECIP IS NOT
EXPECTED...BUT AGAIN CLOUD COVER WILL BE MAINTAINED WITH THE UPPER
LEVEL SYSTEM.

MODELS ARE SHOWING SOME IMPROVEMENT SUNDAY...PARTICULARLY OVER THE
WEST AND FAR SOUTH. HOWEVER...MODEL SOUNDINGS FOR THE REST OF THE
REGION STILL WANT TO MAINTAIN A SATURATED LAYER AROUND 2500FT FOR
MOST OF THE DAY...WHICH DOES NOT PRESENT MUCH HOPE FOR SUNSHINE.
CLOUDS WILL BE TRICKY ON SUNDAY...TRYING TO DETERMINE HOW MUCH OF
THE CLOUD DECK WILL BE ERODED.

SPLIT FLOW DEVELOPS ON MONDAY WITH A LARGE SYSTEM TO THE WEST AND
ANOTHER SYSTEM TO THE SOUTH-SOUTHEAST. IT APPEARS THAT THE AREA
WILL LIE IN BETWEEN LIMITING THE CHANCES FOR PRECIPITATION. WAA
WILL CONTINUE ON MONDAY AND LOW-LEVEL MOISTURE INCREASES ONCE
AGAIN. LOOKS LIKE A GOOD DEAL OF CLOUD COVER AGAIN MONDAY. A WEAK
AND UNORGANIZED SHORTWAVE TROUGH WILL SWING THROUGH MONDAY...
ALLOWING FOR THE POSSIBILITY OF SOME LIGHT PRECIP...MAINLY OVER
THE SOUTHERN RIDGES. THIS WILL NEED TO BE FINE TUNED AS THE WARMER
AIR ALOFT MAY OCCUR BEFORE SURFACE TEMPS RESPOND. CONFIDENCE IS
LOW THAT ANY PRECIP WILL OCCUR...SO FOR FORECAST WILL LEAVE OUT.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
STILL SEEING SOME MINOR DIFFERENCES IN MEDIUM RANGE MODEL
SOLUTIONS FOR MIDWEEK SYSTEM. THINK MUCH OF TUESDAY COULD BE DRY
OR JUST LIGHT SHOWERS AS AREA WILL BE WELL INTO THE WARM SECTOR. RAIN
WILL OVERSPREAD THE AREA TUESDAY NIGHT AHEAD OF OCCLUDED FRONT AND
CONTINUE THROUGH WEDNESDAY. COLDER AIR WILL MOVE IN LATER
WEDNESDAY NIGHT CHANGING ANY LINGERING SHOWERS TO SNOW SHOWERS.
COULD SEE A BRIEF UPTICK IN SNOW SHOWER COVERAGE EARLY THURSDAY
MORNING AS MAIN TROUGH SWINGS THROUGH. COLD AIR WILL BE IN PLACE
THURSDAY...BUT WIND DIRECTION NOT OPTIMAL FOR LAKE INFLUENCED SNOW
SHOWERS.

WARMER AIR WILL MOVE BACK IN THURSDAY NIGHT AND FRIDAY.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
LOW LEVEL MOISTURE WILL REMAIN TRAPPED UNDER A STRONG INVERSION
AOB 4KFT AS LOW LEVEL WINDS BECOME LIGHT....MAINTAINING HIGH MVFR
TO LOW VFR CONDITIONS OVER THE NEXT 24 HOURS. PRECIPITATION
CHANCES ARE MINIMAL GIVEN THE SHALLOW DEPTH OF THE SATURATED
LAYER AND ABSENCE OF ANY LIFT.

OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST THROUGH THE WEEKEND. NEXT STORM
SYSTEM WILL BEGIN TO IMPACT THE REGION ON TUESDAY AND RESULT IN
WIDESPREAD RAIN...CIG/VIS RESTRICTIONS...AND PERIODS OF LLWS
THROUGH WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$






000
FXUS61 KPBZ 201154
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
654 AM EST SAT DEC 20 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...

THE CURRENT FORECAST LOOKS TO BE IN GOOD SHAPE. NO UPDATES WILL BE
NEEDED EARLY THIS MORNING. PREV DISCUSSION FOLLOWS..

WEAK RIDGE BREAKS DOWN
LATER TODAY AS SHORTWAVE TROUGH WILL MOVE THROUGH THE UPPER
MIDWEST. WEAK CAA IS EXPECTED WITH THIS FEATURE WHICH WILL HELP TO
MAINTAIN CLOUD COVER.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
SHORTWAVE TROUGH WILL SWING THROUGH TONIGHT. PRECIP IS NOT
EXPECTED...BUT AGAIN CLOUD COVER WILL BE MAINTAINED WITH THE UPPER
LEVEL SYSTEM.

MODELS ARE SHOWING SOME IMPROVEMENT SUNDAY...PARTICULARLY OVER THE
WEST AND FAR SOUTH. HOWEVER...MODEL SOUNDINGS FOR THE REST OF THE
REGION STILL WANT TO MAINTAIN A SATURATED LAYER AROUND 2500FT FOR
MOST OF THE DAY...WHICH DOES NOT PRESENT MUCH HOPE FOR SUNSHINE.
CLOUDS WILL BE TRICKY ON SUNDAY...TRYING TO DETERMINE HOW MUCH OF
THE CLOUD DECK WILL BE ERODED.

SPLIT FLOW DEVELOPS ON MONDAY WITH A LARGE SYSTEM TO THE WEST AND
ANOTHER SYSTEM TO THE SOUTH-SOUTHEAST. IT APPEARS THAT THE AREA
WILL LIE IN BETWEEN LIMITING THE CHANCES FOR PRECIPITATION. WAA
WILL CONTINUE ON MONDAY AND LOW-LEVEL MOISTURE INCREASES ONCE
AGAIN. LOOKS LIKE A GOOD DEAL OF CLOUD COVER AGAIN MONDAY. A WEAK
AND UNORGANIZED SHORTWAVE TROUGH WILL SWING THROUGH MONDAY...
ALLOWING FOR THE POSSIBILITY OF SOME LIGHT PRECIP...MAINLY OVER
THE SOUTHERN RIDGES. THIS WILL NEED TO BE FINE TUNED AS THE WARMER
AIR ALOFT MAY OCCUR BEFORE SURFACE TEMPS RESPOND. CONFIDENCE IS
LOW THAT ANY PRECIP WILL OCCUR...SO FOR FORECAST WILL LEAVE OUT.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
STILL SEEING SOME MINOR DIFFERENCES IN MEDIUM RANGE MODEL
SOLUTIONS FOR MIDWEEK SYSTEM. THINK MUCH OF TUESDAY COULD BE DRY
OR JUST LIGHT SHOWERS AS AREA WILL BE WELL INTO THE WARM SECTOR. RAIN
WILL OVERSPREAD THE AREA TUESDAY NIGHT AHEAD OF OCCLUDED FRONT AND
CONTINUE THROUGH WEDNESDAY. COLDER AIR WILL MOVE IN LATER
WEDNESDAY NIGHT CHANGING ANY LINGERING SHOWERS TO SNOW SHOWERS.
COULD SEE A BRIEF UPTICK IN SNOW SHOWER COVERAGE EARLY THURSDAY
MORNING AS MAIN TROUGH SWINGS THROUGH. COLD AIR WILL BE IN PLACE
THURSDAY...BUT WIND DIRECTION NOT OPTIMAL FOR LAKE INFLUENCED SNOW
SHOWERS.

WARMER AIR WILL MOVE BACK IN THURSDAY NIGHT AND FRIDAY.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
LOW LEVEL MOISTURE WILL REMAIN TRAPPED UNDER A STRONG INVERSION
AOB 4KFT AS LOW LEVEL WINDS BECOME LIGHT....MAINTAINING HIGH MVFR
TO LOW VFR CONDITIONS OVER THE NEXT 24 HOURS. PRECIPITATION
CHANCES ARE MINIMAL GIVEN THE SHALLOW DEPTH OF THE SATURATED
LAYER AND ABSENCE OF ANY LIFT.

OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST THROUGH THE WEEKEND. NEXT STORM
SYSTEM WILL BEGIN TO IMPACT THE REGION ON TUESDAY AND RESULT IN
WIDESPREAD RAIN...CIG/VIS RESTRICTIONS...AND PERIODS OF LLWS
THROUGH WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$







000
FXUS61 KCTP 201140
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
640 AM EST SAT DEC 20 2014

.SYNOPSIS...
A HIGH PRESSURE AREA CENTERED OVER THE GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND. A DEEP UPPER TROUGH AND
ASSOCIATED SFC LOW WILL LIFT NORTHEAST THROUGH THE GREAT LAKES
DURING THE MIDDLE OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK REMAINS TRAPPED
BENEATH SUBSIDENCE INVERSION THIS MORNING. THERE HAS BEEN SOME
CLEARING ACROSS THE SC MTNS EARLY THIS AM. HOWEVER...CIRRUS SHIELD
IN ADVANCE OF APPROACHING SHORTWAVE SHOULD OVERSPREAD THE AREA
BTWN 12Z-14Z.

LACK OF SUNSHINE AND LOW DECEMBER SUN ANGLE WILL RESULT IN TEMPS
RISING LITTLE FROM AM LOWS...WITH HIGHS IN THE LOW TO MID 30S
MOST PLACES.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
NEXT SHORTWAVE...OVR IOWA AT 09Z...WILL TRACK ACROSS THE REGION
TONIGHT. THIS MOISTURE-STARVED FEATURE SHOULD PRODUCE PLENTY OF
MID LVL CLOUDINESS TONIGHT...BUT PROBABLY NO PRECIP DUE TO DRY AIR
IN THE 0-3KM LAYER. STILL...CAN/T RULE OUT A FLURRY IN SPOTS.

IN WAKE OF TONIGHT/S SHORTWAVE...A GOOD DEAL OF SUNSHINE IS
EXPECTED SUNDAY UNDER RIDGING AT SFC AND ALOFT. CONSALL OUTPUT
SUGGESTS MAX TEMPS WILL RANGE FROM THE 30S MOST PLACES...TO THE
L40S ACROSS THE LOWER SUSQ VALLEY.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
INCREASINGLY MOIST SERLY FLOW WILL DEVELOP OFF THE ATLANTIC EARLY
NEXT WEEK IN GRADIENT BTWN RETREATING HIGH OVR NEW ENG AND WEAK
LOW RIDING UP THE E COAST. THE INFLUX OF LOW LVL MOISTURE...COMBINED
WITH OROGRAPHIC LIFT...WILL LIKELY YIELD DAMP AND DRIZZLY WX MON
NITE THROUGH TUESDAY. MDLS HINT AT PERHAPS JUST ENOUGH LOW LVL
COLD AIR FOR AN INITIAL PERIOD OF -FZRA/FZDZ OVR THE HIGHER
TERRAIN OF THE APPALACHIANS MON NITE.

MED RANGE GUIDANCE HAS CONVERGED ON TIMING/TRACK OF DEEP TROUGH
AND ASSOC SFC LOW DURING MID WEEK...ALL OF WHICH POINTS TOWARD A
MILD AND RAINY CHRISTMAS EVE IN WARM SECTOR OF THIS SYSTEM. BLEND
OF MED RANGE GUIDANCE SUPPORTS ARND 1 INCH OF RAIN...FALLING
MOSTLY WITH PASSAGE OF LL JET/PLUME OF ANOMALOUS PWATS WEDNESDAY.
SURGE OF VERY WARM AIR SHOULD PRECEDE THE TRAILING COLD FRONT...PUSHING
READINGS INTO THE 50S OVR MOST OF THE AREA WEDNESDAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS IS LIKELY WED NIGHT INTO THURSDAY OVR THE W MTNS...PERHAPS
BRINGING A WHITE XMAS TO THE ALLEGHENY PLATEAU. THE BIGGER STORY
MAY BE THE STRONG/GUSTY WINDS WED NITE/THURSDAY. DEEPENING SFC
LOWS TRACKING THRU THE E GRT LKS TYPICALLY BRING CENTRAL PA SOME
OF OUR STRONGEST WINDS AND LATEST GUIDANCE SUGGESTS WINDS COULD
BE NEAR ADVISORY CRITERIA ON CHRISTMAS.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
00Z ECENS AND GEFS SHOWING THE UPPER TROF QUICKLY LIFTING OUT BY
FRIDAY.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
A HIGH PRESSURE AREA CENTERED OVER THE GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND.

SHALLOW STRATOCU DECK REMAINS TRAPPED BENEATH SUBSIDENCE
INVERSION THIS MORNING...THOUGH THERE HAS BEEN SOME CLEARING
ACROSS THE SC MTNS OVER THE PAST SEVERAL HOURS. MUCH OF THE REGION
REMAINS MVFR AT 12Z /WITH THE NW MTNS AND KBFD SLIPPING TO IFR
CIGS OCCASIONALLY/. CIGS SHOULD IMPROVE IN MOST PLACES BY LATE
MORNING...BUT LOWER CIGS WILL PERSIST IN THE NORTHERN MTNS. HIGH
CLOUDS INCREASE LATER THIS MORNING AS WAA ALOFT OVERSPREADS THE
AREA IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE OHIO VALLEY. WINDS
WILL BE LIGHT FROM THE WEST.

CIG RESTRICTIONS IN EXPANDING STRATOCU DECK LIKELY RETURN AGAIN
TONIGHT...THOUGH LOW CLOUDS SHOULD NOT BE QUITE AS EXPANSIVE AS
PREVIOUS NIGHTS. A SHORTWAVE WILL TRACK ACROSS THE REGION BRINGING
A THICKENING MID-LVL DECK AS WELL. SURFACE WINDS WILL CONTINUE TO
BE LIGHT...WITH SW FLOW ALOFT BEGINNING TO INCREASE AS A LARGE LOW
PRESSURE SYSTEM BEGINS TO DEEPEN OVER THE CENTRAL U.S.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/EVANEGO
AVIATION...RXR




000
FXUS61 KCTP 201140
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
640 AM EST SAT DEC 20 2014

.SYNOPSIS...
A HIGH PRESSURE AREA CENTERED OVER THE GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND. A DEEP UPPER TROUGH AND
ASSOCIATED SFC LOW WILL LIFT NORTHEAST THROUGH THE GREAT LAKES
DURING THE MIDDLE OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK REMAINS TRAPPED
BENEATH SUBSIDENCE INVERSION THIS MORNING. THERE HAS BEEN SOME
CLEARING ACROSS THE SC MTNS EARLY THIS AM. HOWEVER...CIRRUS SHIELD
IN ADVANCE OF APPROACHING SHORTWAVE SHOULD OVERSPREAD THE AREA
BTWN 12Z-14Z.

LACK OF SUNSHINE AND LOW DECEMBER SUN ANGLE WILL RESULT IN TEMPS
RISING LITTLE FROM AM LOWS...WITH HIGHS IN THE LOW TO MID 30S
MOST PLACES.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
NEXT SHORTWAVE...OVR IOWA AT 09Z...WILL TRACK ACROSS THE REGION
TONIGHT. THIS MOISTURE-STARVED FEATURE SHOULD PRODUCE PLENTY OF
MID LVL CLOUDINESS TONIGHT...BUT PROBABLY NO PRECIP DUE TO DRY AIR
IN THE 0-3KM LAYER. STILL...CAN/T RULE OUT A FLURRY IN SPOTS.

IN WAKE OF TONIGHT/S SHORTWAVE...A GOOD DEAL OF SUNSHINE IS
EXPECTED SUNDAY UNDER RIDGING AT SFC AND ALOFT. CONSALL OUTPUT
SUGGESTS MAX TEMPS WILL RANGE FROM THE 30S MOST PLACES...TO THE
L40S ACROSS THE LOWER SUSQ VALLEY.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
INCREASINGLY MOIST SERLY FLOW WILL DEVELOP OFF THE ATLANTIC EARLY
NEXT WEEK IN GRADIENT BTWN RETREATING HIGH OVR NEW ENG AND WEAK
LOW RIDING UP THE E COAST. THE INFLUX OF LOW LVL MOISTURE...COMBINED
WITH OROGRAPHIC LIFT...WILL LIKELY YIELD DAMP AND DRIZZLY WX MON
NITE THROUGH TUESDAY. MDLS HINT AT PERHAPS JUST ENOUGH LOW LVL
COLD AIR FOR AN INITIAL PERIOD OF -FZRA/FZDZ OVR THE HIGHER
TERRAIN OF THE APPALACHIANS MON NITE.

MED RANGE GUIDANCE HAS CONVERGED ON TIMING/TRACK OF DEEP TROUGH
AND ASSOC SFC LOW DURING MID WEEK...ALL OF WHICH POINTS TOWARD A
MILD AND RAINY CHRISTMAS EVE IN WARM SECTOR OF THIS SYSTEM. BLEND
OF MED RANGE GUIDANCE SUPPORTS ARND 1 INCH OF RAIN...FALLING
MOSTLY WITH PASSAGE OF LL JET/PLUME OF ANOMALOUS PWATS WEDNESDAY.
SURGE OF VERY WARM AIR SHOULD PRECEDE THE TRAILING COLD FRONT...PUSHING
READINGS INTO THE 50S OVR MOST OF THE AREA WEDNESDAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS IS LIKELY WED NIGHT INTO THURSDAY OVR THE W MTNS...PERHAPS
BRINGING A WHITE XMAS TO THE ALLEGHENY PLATEAU. THE BIGGER STORY
MAY BE THE STRONG/GUSTY WINDS WED NITE/THURSDAY. DEEPENING SFC
LOWS TRACKING THRU THE E GRT LKS TYPICALLY BRING CENTRAL PA SOME
OF OUR STRONGEST WINDS AND LATEST GUIDANCE SUGGESTS WINDS COULD
BE NEAR ADVISORY CRITERIA ON CHRISTMAS.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
00Z ECENS AND GEFS SHOWING THE UPPER TROF QUICKLY LIFTING OUT BY
FRIDAY.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
A HIGH PRESSURE AREA CENTERED OVER THE GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND.

SHALLOW STRATOCU DECK REMAINS TRAPPED BENEATH SUBSIDENCE
INVERSION THIS MORNING...THOUGH THERE HAS BEEN SOME CLEARING
ACROSS THE SC MTNS OVER THE PAST SEVERAL HOURS. MUCH OF THE REGION
REMAINS MVFR AT 12Z /WITH THE NW MTNS AND KBFD SLIPPING TO IFR
CIGS OCCASIONALLY/. CIGS SHOULD IMPROVE IN MOST PLACES BY LATE
MORNING...BUT LOWER CIGS WILL PERSIST IN THE NORTHERN MTNS. HIGH
CLOUDS INCREASE LATER THIS MORNING AS WAA ALOFT OVERSPREADS THE
AREA IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE OHIO VALLEY. WINDS
WILL BE LIGHT FROM THE WEST.

CIG RESTRICTIONS IN EXPANDING STRATOCU DECK LIKELY RETURN AGAIN
TONIGHT...THOUGH LOW CLOUDS SHOULD NOT BE QUITE AS EXPANSIVE AS
PREVIOUS NIGHTS. A SHORTWAVE WILL TRACK ACROSS THE REGION BRINGING
A THICKENING MID-LVL DECK AS WELL. SURFACE WINDS WILL CONTINUE TO
BE LIGHT...WITH SW FLOW ALOFT BEGINNING TO INCREASE AS A LARGE LOW
PRESSURE SYSTEM BEGINS TO DEEPEN OVER THE CENTRAL U.S.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/EVANEGO
AVIATION...RXR




000
FXUS61 KCTP 201140
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
640 AM EST SAT DEC 20 2014

.SYNOPSIS...
A HIGH PRESSURE AREA CENTERED OVER THE GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND. A DEEP UPPER TROUGH AND
ASSOCIATED SFC LOW WILL LIFT NORTHEAST THROUGH THE GREAT LAKES
DURING THE MIDDLE OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK REMAINS TRAPPED
BENEATH SUBSIDENCE INVERSION THIS MORNING. THERE HAS BEEN SOME
CLEARING ACROSS THE SC MTNS EARLY THIS AM. HOWEVER...CIRRUS SHIELD
IN ADVANCE OF APPROACHING SHORTWAVE SHOULD OVERSPREAD THE AREA
BTWN 12Z-14Z.

LACK OF SUNSHINE AND LOW DECEMBER SUN ANGLE WILL RESULT IN TEMPS
RISING LITTLE FROM AM LOWS...WITH HIGHS IN THE LOW TO MID 30S
MOST PLACES.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
NEXT SHORTWAVE...OVR IOWA AT 09Z...WILL TRACK ACROSS THE REGION
TONIGHT. THIS MOISTURE-STARVED FEATURE SHOULD PRODUCE PLENTY OF
MID LVL CLOUDINESS TONIGHT...BUT PROBABLY NO PRECIP DUE TO DRY AIR
IN THE 0-3KM LAYER. STILL...CAN/T RULE OUT A FLURRY IN SPOTS.

IN WAKE OF TONIGHT/S SHORTWAVE...A GOOD DEAL OF SUNSHINE IS
EXPECTED SUNDAY UNDER RIDGING AT SFC AND ALOFT. CONSALL OUTPUT
SUGGESTS MAX TEMPS WILL RANGE FROM THE 30S MOST PLACES...TO THE
L40S ACROSS THE LOWER SUSQ VALLEY.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
INCREASINGLY MOIST SERLY FLOW WILL DEVELOP OFF THE ATLANTIC EARLY
NEXT WEEK IN GRADIENT BTWN RETREATING HIGH OVR NEW ENG AND WEAK
LOW RIDING UP THE E COAST. THE INFLUX OF LOW LVL MOISTURE...COMBINED
WITH OROGRAPHIC LIFT...WILL LIKELY YIELD DAMP AND DRIZZLY WX MON
NITE THROUGH TUESDAY. MDLS HINT AT PERHAPS JUST ENOUGH LOW LVL
COLD AIR FOR AN INITIAL PERIOD OF -FZRA/FZDZ OVR THE HIGHER
TERRAIN OF THE APPALACHIANS MON NITE.

MED RANGE GUIDANCE HAS CONVERGED ON TIMING/TRACK OF DEEP TROUGH
AND ASSOC SFC LOW DURING MID WEEK...ALL OF WHICH POINTS TOWARD A
MILD AND RAINY CHRISTMAS EVE IN WARM SECTOR OF THIS SYSTEM. BLEND
OF MED RANGE GUIDANCE SUPPORTS ARND 1 INCH OF RAIN...FALLING
MOSTLY WITH PASSAGE OF LL JET/PLUME OF ANOMALOUS PWATS WEDNESDAY.
SURGE OF VERY WARM AIR SHOULD PRECEDE THE TRAILING COLD FRONT...PUSHING
READINGS INTO THE 50S OVR MOST OF THE AREA WEDNESDAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS IS LIKELY WED NIGHT INTO THURSDAY OVR THE W MTNS...PERHAPS
BRINGING A WHITE XMAS TO THE ALLEGHENY PLATEAU. THE BIGGER STORY
MAY BE THE STRONG/GUSTY WINDS WED NITE/THURSDAY. DEEPENING SFC
LOWS TRACKING THRU THE E GRT LKS TYPICALLY BRING CENTRAL PA SOME
OF OUR STRONGEST WINDS AND LATEST GUIDANCE SUGGESTS WINDS COULD
BE NEAR ADVISORY CRITERIA ON CHRISTMAS.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
00Z ECENS AND GEFS SHOWING THE UPPER TROF QUICKLY LIFTING OUT BY
FRIDAY.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
A HIGH PRESSURE AREA CENTERED OVER THE GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND.

SHALLOW STRATOCU DECK REMAINS TRAPPED BENEATH SUBSIDENCE
INVERSION THIS MORNING...THOUGH THERE HAS BEEN SOME CLEARING
ACROSS THE SC MTNS OVER THE PAST SEVERAL HOURS. MUCH OF THE REGION
REMAINS MVFR AT 12Z /WITH THE NW MTNS AND KBFD SLIPPING TO IFR
CIGS OCCASIONALLY/. CIGS SHOULD IMPROVE IN MOST PLACES BY LATE
MORNING...BUT LOWER CIGS WILL PERSIST IN THE NORTHERN MTNS. HIGH
CLOUDS INCREASE LATER THIS MORNING AS WAA ALOFT OVERSPREADS THE
AREA IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE OHIO VALLEY. WINDS
WILL BE LIGHT FROM THE WEST.

CIG RESTRICTIONS IN EXPANDING STRATOCU DECK LIKELY RETURN AGAIN
TONIGHT...THOUGH LOW CLOUDS SHOULD NOT BE QUITE AS EXPANSIVE AS
PREVIOUS NIGHTS. A SHORTWAVE WILL TRACK ACROSS THE REGION BRINGING
A THICKENING MID-LVL DECK AS WELL. SURFACE WINDS WILL CONTINUE TO
BE LIGHT...WITH SW FLOW ALOFT BEGINNING TO INCREASE AS A LARGE LOW
PRESSURE SYSTEM BEGINS TO DEEPEN OVER THE CENTRAL U.S.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/EVANEGO
AVIATION...RXR




000
FXUS61 KCTP 201140
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
640 AM EST SAT DEC 20 2014

.SYNOPSIS...
A HIGH PRESSURE AREA CENTERED OVER THE GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND. A DEEP UPPER TROUGH AND
ASSOCIATED SFC LOW WILL LIFT NORTHEAST THROUGH THE GREAT LAKES
DURING THE MIDDLE OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK REMAINS TRAPPED
BENEATH SUBSIDENCE INVERSION THIS MORNING. THERE HAS BEEN SOME
CLEARING ACROSS THE SC MTNS EARLY THIS AM. HOWEVER...CIRRUS SHIELD
IN ADVANCE OF APPROACHING SHORTWAVE SHOULD OVERSPREAD THE AREA
BTWN 12Z-14Z.

LACK OF SUNSHINE AND LOW DECEMBER SUN ANGLE WILL RESULT IN TEMPS
RISING LITTLE FROM AM LOWS...WITH HIGHS IN THE LOW TO MID 30S
MOST PLACES.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
NEXT SHORTWAVE...OVR IOWA AT 09Z...WILL TRACK ACROSS THE REGION
TONIGHT. THIS MOISTURE-STARVED FEATURE SHOULD PRODUCE PLENTY OF
MID LVL CLOUDINESS TONIGHT...BUT PROBABLY NO PRECIP DUE TO DRY AIR
IN THE 0-3KM LAYER. STILL...CAN/T RULE OUT A FLURRY IN SPOTS.

IN WAKE OF TONIGHT/S SHORTWAVE...A GOOD DEAL OF SUNSHINE IS
EXPECTED SUNDAY UNDER RIDGING AT SFC AND ALOFT. CONSALL OUTPUT
SUGGESTS MAX TEMPS WILL RANGE FROM THE 30S MOST PLACES...TO THE
L40S ACROSS THE LOWER SUSQ VALLEY.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
INCREASINGLY MOIST SERLY FLOW WILL DEVELOP OFF THE ATLANTIC EARLY
NEXT WEEK IN GRADIENT BTWN RETREATING HIGH OVR NEW ENG AND WEAK
LOW RIDING UP THE E COAST. THE INFLUX OF LOW LVL MOISTURE...COMBINED
WITH OROGRAPHIC LIFT...WILL LIKELY YIELD DAMP AND DRIZZLY WX MON
NITE THROUGH TUESDAY. MDLS HINT AT PERHAPS JUST ENOUGH LOW LVL
COLD AIR FOR AN INITIAL PERIOD OF -FZRA/FZDZ OVR THE HIGHER
TERRAIN OF THE APPALACHIANS MON NITE.

MED RANGE GUIDANCE HAS CONVERGED ON TIMING/TRACK OF DEEP TROUGH
AND ASSOC SFC LOW DURING MID WEEK...ALL OF WHICH POINTS TOWARD A
MILD AND RAINY CHRISTMAS EVE IN WARM SECTOR OF THIS SYSTEM. BLEND
OF MED RANGE GUIDANCE SUPPORTS ARND 1 INCH OF RAIN...FALLING
MOSTLY WITH PASSAGE OF LL JET/PLUME OF ANOMALOUS PWATS WEDNESDAY.
SURGE OF VERY WARM AIR SHOULD PRECEDE THE TRAILING COLD FRONT...PUSHING
READINGS INTO THE 50S OVR MOST OF THE AREA WEDNESDAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS IS LIKELY WED NIGHT INTO THURSDAY OVR THE W MTNS...PERHAPS
BRINGING A WHITE XMAS TO THE ALLEGHENY PLATEAU. THE BIGGER STORY
MAY BE THE STRONG/GUSTY WINDS WED NITE/THURSDAY. DEEPENING SFC
LOWS TRACKING THRU THE E GRT LKS TYPICALLY BRING CENTRAL PA SOME
OF OUR STRONGEST WINDS AND LATEST GUIDANCE SUGGESTS WINDS COULD
BE NEAR ADVISORY CRITERIA ON CHRISTMAS.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
00Z ECENS AND GEFS SHOWING THE UPPER TROF QUICKLY LIFTING OUT BY
FRIDAY.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
A HIGH PRESSURE AREA CENTERED OVER THE GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND.

SHALLOW STRATOCU DECK REMAINS TRAPPED BENEATH SUBSIDENCE
INVERSION THIS MORNING...THOUGH THERE HAS BEEN SOME CLEARING
ACROSS THE SC MTNS OVER THE PAST SEVERAL HOURS. MUCH OF THE REGION
REMAINS MVFR AT 12Z /WITH THE NW MTNS AND KBFD SLIPPING TO IFR
CIGS OCCASIONALLY/. CIGS SHOULD IMPROVE IN MOST PLACES BY LATE
MORNING...BUT LOWER CIGS WILL PERSIST IN THE NORTHERN MTNS. HIGH
CLOUDS INCREASE LATER THIS MORNING AS WAA ALOFT OVERSPREADS THE
AREA IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE OHIO VALLEY. WINDS
WILL BE LIGHT FROM THE WEST.

CIG RESTRICTIONS IN EXPANDING STRATOCU DECK LIKELY RETURN AGAIN
TONIGHT...THOUGH LOW CLOUDS SHOULD NOT BE QUITE AS EXPANSIVE AS
PREVIOUS NIGHTS. A SHORTWAVE WILL TRACK ACROSS THE REGION BRINGING
A THICKENING MID-LVL DECK AS WELL. SURFACE WINDS WILL CONTINUE TO
BE LIGHT...WITH SW FLOW ALOFT BEGINNING TO INCREASE AS A LARGE LOW
PRESSURE SYSTEM BEGINS TO DEEPEN OVER THE CENTRAL U.S.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/EVANEGO
AVIATION...RXR




000
FXUS61 KCTP 201122
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
622 AM EST SAT DEC 20 2014

.SYNOPSIS...
A HIGH PRESSURE AREA CENTERED OVER THE GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND. A DEEP UPPER TROUGH AND
ASSOCIATED SFC LOW WILL LIFT NORTHEAST THROUGH THE GREAT LAKES
DURING THE MIDDLE OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK REMAINS TRAPPED
BENEATH SUBSIDENCE INVERSION THIS MORNING. THERE HAS BEEN SOME
CLEARING ACROSS THE SC MTNS AND NR TERM MDL SOUNDINGS INDICATE
THIS AREA WILL REMAIN MCLEAR THRU DAWN...WHILE STRATOCU PERSISTS
ELSEWHERE. EARLY SUNSHINE IN THE SOUTH WILL FADE BENEATH INCREASING
HIGH CLOUDS LATER THIS MORNING...AS WAA ALOFT OVERSPREADS THE AREA
IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE OHIO VALLEY.

LACK OF SUNSHINE AND LOW DECEMBER SUN ANGLE WILL RESULT IN TEMPS
RISING LITTLE FROM AM LOWS...WITH HIGHS IN THE LOW TO MID 30S
MOST PLACES.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
NEXT SHORTWAVE...OVR IOWA AT 09Z...WILL TRACK ACROSS THE REGION
TONIGHT. THIS MOISTURE-STARVED FEATURE SHOULD PRODUCE PLENTY OF
MID LVL CLOUDINESS TONIGHT...BUT PROBABLY NO PRECIP DUE TO DRY AIR
IN THE 0-3KM LAYER. STILL...CAN/T RULE OUT A FLURRY IN SPOTS.

IN WAKE OF TONIGHT/S SHORTWAVE...A GOOD DEAL OF SUNSHINE IS
EXPECTED SUNDAY UNDER RIDGING AT SFC AND ALOFT. CONSALL OUTPUT
SUGGESTS MAX TEMPS WILL RANGE FROM THE 30S MOST PLACES...TO THE
L40S ACROSS THE LOWER SUSQ VALLEY.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
INCREASINGLY MOIST SERLY FLOW WILL DEVELOP OFF THE ATLANTIC EARLY
NEXT WEEK IN GRADIENT BTWN RETREATING HIGH OVR NEW ENG AND WEAK
LOW RIDING UP THE E COAST. THE INFLUX OF LOW LVL MOISTURE...COMBINED
WITH OROGRAPHIC LIFT...WILL LIKELY YIELD DAMP AND DRIZZLY WX MON
NITE THROUGH TUESDAY. MDLS HINT AT PERHAPS JUST ENOUGH LOW LVL
COLD AIR FOR AN INITIAL PERIOD OF -FZRA/FZDZ OVR THE HIGHER
TERRAIN OF THE APPALACHIANS MON NITE.

MED RANGE GUIDANCE HAS CONVERGED ON TIMING/TRACK OF DEEP TROUGH
AND ASSOC SFC LOW DURING MID WEEK...ALL OF WHICH POINTS TOWARD A
MILD AND RAINY CHRISTMAS EVE IN WARM SECTOR OF THIS SYSTEM. BLEND
OF MED RANGE GUIDANCE SUPPORTS ARND 1 INCH OF RAIN...FALLING
MOSTLY WITH PASSAGE OF LL JET/PLUME OF ANOMALOUS PWATS WEDNESDAY.
SURGE OF VERY WARM AIR SHOULD PRECEDE THE TRAILING COLD FRONT...PUSHING
READINGS INTO THE 50S OVR MOST OF THE AREA WEDNESDAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS IS LIKELY WED NIGHT INTO THURSDAY OVR THE W MTNS...PERHAPS
BRINGING A WHITE XMAS TO THE ALLEGHENY PLATEAU. THE BIGGER STORY
MAY BE THE STRONG/GUSTY WINDS WED NITE/THURSDAY. DEEPENING SFC
LOWS TRACKING THRU THE E GRT LKS TYPICALLY BRING CENTRAL PA SOME
OF OUR STRONGEST WINDS AND LATEST GUIDANCE SUGGESTS WINDS COULD
BE NEAR ADVISORY CRITERIA ON CHRISTMAS.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
00Z ECENS AND GEFS SHOWING THE UPPER TROF QUICKLY LIFTING OUT BY
FRIDAY.

&&

.AVIATION /11Z SATURDAY THROUGH WEDNESDAY/...
A HIGH PRESSURE AREA CENTERED OVER THE GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND.

SHALLOW STRATOCU DECK REMAINS TRAPPED BENEATH SUBSIDENCE
INVERSION THIS MORNING...THOUGH THERE HAS BEEN SOME CLEARING
ACROSS THE SC MTNS OVER THE PAST SEVERAL HOURS. MUCH OF THE REGION
REMAINS MVFR AT 12Z /WITH THE NW MTNS AND KBFD SLIPPING TO IFR
CIGS OCCASIONALLY/. CIGS SHOULD IMPROVE IN MOST PLACES BY LATE
MORNING...BUT LOWER CIGS WILL PERSIST IN THE NORTHERN MTNS. HIGH
CLOUDS INCREASE LATER THIS MORNING AS WAA ALOFT OVERSPREADS THE
AREA IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE OHIO VALLEY. WINDS
WILL BE LIGHT FROM THE WEST.

CIG RESTRICTIONS IN EXPANDING STRATOCU DECK LIKELY RETURN AGAIN
TONIGHT...THOUGH LOW CLOUDS SHOULD NOT BE QUITE AS EXPANSIVE AS
PREVIOUS NIGHTS. A SHORTWAVE WILL TRACK ACROSS THE REGION BRINGING
A THICKENING MID-LVL DECK AS WELL. SURFACE WINDS WILL CONTINUE TO
BE LIGHT...WITH SW FLOW ALOFT BEGINNING TO INCREASE AS A LARGE LOW
PRESSURE SYSTEM BEGINS TO DEEPEN OVER THE CENTRAL U.S.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/EVANEGO
AVIATION...RXR



000
FXUS61 KCTP 201122
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
622 AM EST SAT DEC 20 2014

.SYNOPSIS...
A HIGH PRESSURE AREA CENTERED OVER THE GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND. A DEEP UPPER TROUGH AND
ASSOCIATED SFC LOW WILL LIFT NORTHEAST THROUGH THE GREAT LAKES
DURING THE MIDDLE OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK REMAINS TRAPPED
BENEATH SUBSIDENCE INVERSION THIS MORNING. THERE HAS BEEN SOME
CLEARING ACROSS THE SC MTNS AND NR TERM MDL SOUNDINGS INDICATE
THIS AREA WILL REMAIN MCLEAR THRU DAWN...WHILE STRATOCU PERSISTS
ELSEWHERE. EARLY SUNSHINE IN THE SOUTH WILL FADE BENEATH INCREASING
HIGH CLOUDS LATER THIS MORNING...AS WAA ALOFT OVERSPREADS THE AREA
IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE OHIO VALLEY.

LACK OF SUNSHINE AND LOW DECEMBER SUN ANGLE WILL RESULT IN TEMPS
RISING LITTLE FROM AM LOWS...WITH HIGHS IN THE LOW TO MID 30S
MOST PLACES.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
NEXT SHORTWAVE...OVR IOWA AT 09Z...WILL TRACK ACROSS THE REGION
TONIGHT. THIS MOISTURE-STARVED FEATURE SHOULD PRODUCE PLENTY OF
MID LVL CLOUDINESS TONIGHT...BUT PROBABLY NO PRECIP DUE TO DRY AIR
IN THE 0-3KM LAYER. STILL...CAN/T RULE OUT A FLURRY IN SPOTS.

IN WAKE OF TONIGHT/S SHORTWAVE...A GOOD DEAL OF SUNSHINE IS
EXPECTED SUNDAY UNDER RIDGING AT SFC AND ALOFT. CONSALL OUTPUT
SUGGESTS MAX TEMPS WILL RANGE FROM THE 30S MOST PLACES...TO THE
L40S ACROSS THE LOWER SUSQ VALLEY.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
INCREASINGLY MOIST SERLY FLOW WILL DEVELOP OFF THE ATLANTIC EARLY
NEXT WEEK IN GRADIENT BTWN RETREATING HIGH OVR NEW ENG AND WEAK
LOW RIDING UP THE E COAST. THE INFLUX OF LOW LVL MOISTURE...COMBINED
WITH OROGRAPHIC LIFT...WILL LIKELY YIELD DAMP AND DRIZZLY WX MON
NITE THROUGH TUESDAY. MDLS HINT AT PERHAPS JUST ENOUGH LOW LVL
COLD AIR FOR AN INITIAL PERIOD OF -FZRA/FZDZ OVR THE HIGHER
TERRAIN OF THE APPALACHIANS MON NITE.

MED RANGE GUIDANCE HAS CONVERGED ON TIMING/TRACK OF DEEP TROUGH
AND ASSOC SFC LOW DURING MID WEEK...ALL OF WHICH POINTS TOWARD A
MILD AND RAINY CHRISTMAS EVE IN WARM SECTOR OF THIS SYSTEM. BLEND
OF MED RANGE GUIDANCE SUPPORTS ARND 1 INCH OF RAIN...FALLING
MOSTLY WITH PASSAGE OF LL JET/PLUME OF ANOMALOUS PWATS WEDNESDAY.
SURGE OF VERY WARM AIR SHOULD PRECEDE THE TRAILING COLD FRONT...PUSHING
READINGS INTO THE 50S OVR MOST OF THE AREA WEDNESDAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS IS LIKELY WED NIGHT INTO THURSDAY OVR THE W MTNS...PERHAPS
BRINGING A WHITE XMAS TO THE ALLEGHENY PLATEAU. THE BIGGER STORY
MAY BE THE STRONG/GUSTY WINDS WED NITE/THURSDAY. DEEPENING SFC
LOWS TRACKING THRU THE E GRT LKS TYPICALLY BRING CENTRAL PA SOME
OF OUR STRONGEST WINDS AND LATEST GUIDANCE SUGGESTS WINDS COULD
BE NEAR ADVISORY CRITERIA ON CHRISTMAS.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
00Z ECENS AND GEFS SHOWING THE UPPER TROF QUICKLY LIFTING OUT BY
FRIDAY.

&&

.AVIATION /11Z SATURDAY THROUGH WEDNESDAY/...
A HIGH PRESSURE AREA CENTERED OVER THE GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND.

SHALLOW STRATOCU DECK REMAINS TRAPPED BENEATH SUBSIDENCE
INVERSION THIS MORNING...THOUGH THERE HAS BEEN SOME CLEARING
ACROSS THE SC MTNS OVER THE PAST SEVERAL HOURS. MUCH OF THE REGION
REMAINS MVFR AT 12Z /WITH THE NW MTNS AND KBFD SLIPPING TO IFR
CIGS OCCASIONALLY/. CIGS SHOULD IMPROVE IN MOST PLACES BY LATE
MORNING...BUT LOWER CIGS WILL PERSIST IN THE NORTHERN MTNS. HIGH
CLOUDS INCREASE LATER THIS MORNING AS WAA ALOFT OVERSPREADS THE
AREA IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE OHIO VALLEY. WINDS
WILL BE LIGHT FROM THE WEST.

CIG RESTRICTIONS IN EXPANDING STRATOCU DECK LIKELY RETURN AGAIN
TONIGHT...THOUGH LOW CLOUDS SHOULD NOT BE QUITE AS EXPANSIVE AS
PREVIOUS NIGHTS. A SHORTWAVE WILL TRACK ACROSS THE REGION BRINGING
A THICKENING MID-LVL DECK AS WELL. SURFACE WINDS WILL CONTINUE TO
BE LIGHT...WITH SW FLOW ALOFT BEGINNING TO INCREASE AS A LARGE LOW
PRESSURE SYSTEM BEGINS TO DEEPEN OVER THE CENTRAL U.S.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/EVANEGO
AVIATION...RXR




000
FXUS61 KCTP 201024
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
524 AM EST SAT DEC 20 2014

.SYNOPSIS...
A HIGH PRESSURE CENTERED OVER THE GREAT LAKES WILL SLIDE EAST
ACROSS PENNSYLVANIA THIS WEEKEND. A DEEP UPPER TROUGH AND
ASSOCIATED SFC LOW WILL LIFT NORTHEAST THROUGH THE GREAT LAKES
DURING THE MIDDLE OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK REMAINS TRAPPED
BENEATH SUBSIDENCE INVERSION THIS MORNING. THERE HAS BEEN SOME
CLEARING ACROSS THE SC MTNS AND NR TERM MDL SOUNDINGS INDICATE
THIS AREA WILL REMAIN MCLEAR THRU DAWN...WHILE STRATOCU PERSISTS
ELSEWHERE. EARLY SUNSHINE IN THE SOUTH WILL FADE BENEATH INCREASING
HIGH CLOUDS LATER THIS MORNING...AS WAA ALOFT OVERSPREADS THE AREA
IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE OHIO VALLEY.

LACK OF SUNSHINE AND LOW DECEMBER SUN ANGLE WILL RESULT IN TEMPS
RISING LITTLE FROM AM LOWS...WITH HIGHS IN THE LOW TO MID 30S
MOST PLACES.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
NEXT SHORTWAVE...OVR IOWA AT 09Z...WILL TRACK ACROSS THE REGION
TONIGHT. THIS MOISTURE-STARVED FEATURE SHOULD PRODUCE PLENTY OF
MID LVL CLOUDINESS TONIGHT...BUT PROBABLY NO PRECIP DUE TO DRY AIR
IN THE 0-3KM LAYER. STILL...CAN/T RULE OUT A FLURRY IN SPOTS.

IN WAKE OF TONIGHT/S SHORTWAVE...A GOOD DEAL OF SUNSHINE IS
EXPECTED SUNDAY UNDER RIDGING AT SFC AND ALOFT. CONSALL OUTPUT
SUGGESTS MAX TEMPS WILL RANGE FROM THE 30S MOST PLACES...TO THE
L40S ACROSS THE LOWER SUSQ VALLEY.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
INCREASINGLY MOIST SERLY FLOW WILL DEVELOP OFF THE ATLANTIC EARLY
NEXT WEEK IN GRADIENT BTWN RETREATING HIGH OVR NEW ENG AND WEAK
LOW RIDING UP THE E COAST. THE INFLUX OF LOW LVL MOISTURE...COMBINED
WITH OROGRAPHIC LIFT...WILL LIKELY YIELD DAMP AND DRIZZLY WX MON
NITE THROUGH TUESDAY. MDLS HINT AT PERHAPS JUST ENOUGH LOW LVL
COLD AIR FOR AN INITIAL PERIOD OF -FZRA/FZDZ OVR THE HIGHER
TERRAIN OF THE APPALACHIANS MON NITE.

MED RANGE GUIDANCE HAS CONVERGED ON TIMING/TRACK OF DEEP TROUGH
AND ASSOC SFC LOW DURING MID WEEK...ALL OF WHICH POINTS TOWARD A
MILD AND RAINY CHRISTMAS EVE IN WARM SECTOR OF THIS SYSTEM. BLEND
OF MED RANGE GUIDANCE SUPPORTS ARND 1 INCH OF RAIN...FALLING
MOSTLY WITH PASSAGE OF LL JET/PLUME OF ANOMALOUS PWATS WEDNESDAY.
SURGE OF VERY WARM AIR SHOULD PRECEDE THE TRAILING COLD FRONT...PUSHING
READINGS INTO THE 50S OVR MOST OF THE AREA WEDNESDAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS IS LIKELY WED NIGHT INTO THURSDAY OVR THE W MTNS...PERHAPS
BRINGING A WHITE XMAS TO THE ALLEGHENY PLATEAU. THE BIGGER STORY
MAY BE THE STRONG/GUSTY WINDS WED NITE/THURSDAY. DEEPENING SFC
LOWS TRACKING THRU THE E GRT LKS TYPICALLY BRING CENTRAL PA SOME
OF OUR STRONGEST WINDS AND LATEST GUIDANCE SUGGESTS WINDS COULD
BE NEAR ADVISORY CRITERIA ON CHRISTMAS.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
00Z ECENS AND GEFS SHOWING THE UPPER TROF QUICKLY LIFTING OUT BY
FRIDAY.

&&

.AVIATION /10Z SATURDAY THROUGH WEDNESDAY/...
NORTHWESTERLY SFC FLOW THAT HAS CAUSED OROGRAPHIC FORCING OF A
SHALLOW MOIST LAYER WILL CONTINUE TO PRODUCE PLENTY OF CLOUDS
ACROSS THE NW AND THE LAURELS WITH MAINLY MVFR BKN-OVC CIGS
THROUGH TONIGHT. KJST AND KBFD WILL TREND IFR THROUGH 12Z...AND
CIGS WILL SLOWLY INCREASE AS THE LOW LEVELS DRY OUT BY MID TO LATE
TOMORROW MORNING. IN CONTRAST...THE SE PENN AIRFIELDS SUCH AS
KMDT...KTHV AND KLNS WILL SEE MAINLY VFR.

NORTHWEST WINDS OF 10-15 KTS WITH HIGHER GUSTS WILL DECREASE TO 8
KTS OR LESS LATER TONIGHT AND SATURDAY.

HIGH PRESSURE BUILDS EAST ACROSS PENN SATURDAY...WITH BKN-OVC CIGS
VARYING BETWEEN MVFR OVER THE HIGHER TERRAIN OF THE NORTH AND
WEST...TO SCT-BKN VFR IN THE VALLEYS.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/EVANEGO
AVIATION...LAMBERT/CERU




000
FXUS61 KCTP 201024
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
524 AM EST SAT DEC 20 2014

.SYNOPSIS...
A HIGH PRESSURE CENTERED OVER THE GREAT LAKES WILL SLIDE EAST
ACROSS PENNSYLVANIA THIS WEEKEND. A DEEP UPPER TROUGH AND
ASSOCIATED SFC LOW WILL LIFT NORTHEAST THROUGH THE GREAT LAKES
DURING THE MIDDLE OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK REMAINS TRAPPED
BENEATH SUBSIDENCE INVERSION THIS MORNING. THERE HAS BEEN SOME
CLEARING ACROSS THE SC MTNS AND NR TERM MDL SOUNDINGS INDICATE
THIS AREA WILL REMAIN MCLEAR THRU DAWN...WHILE STRATOCU PERSISTS
ELSEWHERE. EARLY SUNSHINE IN THE SOUTH WILL FADE BENEATH INCREASING
HIGH CLOUDS LATER THIS MORNING...AS WAA ALOFT OVERSPREADS THE AREA
IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE OHIO VALLEY.

LACK OF SUNSHINE AND LOW DECEMBER SUN ANGLE WILL RESULT IN TEMPS
RISING LITTLE FROM AM LOWS...WITH HIGHS IN THE LOW TO MID 30S
MOST PLACES.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
NEXT SHORTWAVE...OVR IOWA AT 09Z...WILL TRACK ACROSS THE REGION
TONIGHT. THIS MOISTURE-STARVED FEATURE SHOULD PRODUCE PLENTY OF
MID LVL CLOUDINESS TONIGHT...BUT PROBABLY NO PRECIP DUE TO DRY AIR
IN THE 0-3KM LAYER. STILL...CAN/T RULE OUT A FLURRY IN SPOTS.

IN WAKE OF TONIGHT/S SHORTWAVE...A GOOD DEAL OF SUNSHINE IS
EXPECTED SUNDAY UNDER RIDGING AT SFC AND ALOFT. CONSALL OUTPUT
SUGGESTS MAX TEMPS WILL RANGE FROM THE 30S MOST PLACES...TO THE
L40S ACROSS THE LOWER SUSQ VALLEY.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
INCREASINGLY MOIST SERLY FLOW WILL DEVELOP OFF THE ATLANTIC EARLY
NEXT WEEK IN GRADIENT BTWN RETREATING HIGH OVR NEW ENG AND WEAK
LOW RIDING UP THE E COAST. THE INFLUX OF LOW LVL MOISTURE...COMBINED
WITH OROGRAPHIC LIFT...WILL LIKELY YIELD DAMP AND DRIZZLY WX MON
NITE THROUGH TUESDAY. MDLS HINT AT PERHAPS JUST ENOUGH LOW LVL
COLD AIR FOR AN INITIAL PERIOD OF -FZRA/FZDZ OVR THE HIGHER
TERRAIN OF THE APPALACHIANS MON NITE.

MED RANGE GUIDANCE HAS CONVERGED ON TIMING/TRACK OF DEEP TROUGH
AND ASSOC SFC LOW DURING MID WEEK...ALL OF WHICH POINTS TOWARD A
MILD AND RAINY CHRISTMAS EVE IN WARM SECTOR OF THIS SYSTEM. BLEND
OF MED RANGE GUIDANCE SUPPORTS ARND 1 INCH OF RAIN...FALLING
MOSTLY WITH PASSAGE OF LL JET/PLUME OF ANOMALOUS PWATS WEDNESDAY.
SURGE OF VERY WARM AIR SHOULD PRECEDE THE TRAILING COLD FRONT...PUSHING
READINGS INTO THE 50S OVR MOST OF THE AREA WEDNESDAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS IS LIKELY WED NIGHT INTO THURSDAY OVR THE W MTNS...PERHAPS
BRINGING A WHITE XMAS TO THE ALLEGHENY PLATEAU. THE BIGGER STORY
MAY BE THE STRONG/GUSTY WINDS WED NITE/THURSDAY. DEEPENING SFC
LOWS TRACKING THRU THE E GRT LKS TYPICALLY BRING CENTRAL PA SOME
OF OUR STRONGEST WINDS AND LATEST GUIDANCE SUGGESTS WINDS COULD
BE NEAR ADVISORY CRITERIA ON CHRISTMAS.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
00Z ECENS AND GEFS SHOWING THE UPPER TROF QUICKLY LIFTING OUT BY
FRIDAY.

&&

.AVIATION /10Z SATURDAY THROUGH WEDNESDAY/...
NORTHWESTERLY SFC FLOW THAT HAS CAUSED OROGRAPHIC FORCING OF A
SHALLOW MOIST LAYER WILL CONTINUE TO PRODUCE PLENTY OF CLOUDS
ACROSS THE NW AND THE LAURELS WITH MAINLY MVFR BKN-OVC CIGS
THROUGH TONIGHT. KJST AND KBFD WILL TREND IFR THROUGH 12Z...AND
CIGS WILL SLOWLY INCREASE AS THE LOW LEVELS DRY OUT BY MID TO LATE
TOMORROW MORNING. IN CONTRAST...THE SE PENN AIRFIELDS SUCH AS
KMDT...KTHV AND KLNS WILL SEE MAINLY VFR.

NORTHWEST WINDS OF 10-15 KTS WITH HIGHER GUSTS WILL DECREASE TO 8
KTS OR LESS LATER TONIGHT AND SATURDAY.

HIGH PRESSURE BUILDS EAST ACROSS PENN SATURDAY...WITH BKN-OVC CIGS
VARYING BETWEEN MVFR OVER THE HIGHER TERRAIN OF THE NORTH AND
WEST...TO SCT-BKN VFR IN THE VALLEYS.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/EVANEGO
AVIATION...LAMBERT/CERU



000
FXUS61 KPBZ 200909
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
409 AM EST SAT DEC 20 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WEAK RIDGE BREAKS DOWN LATER TODAY AS SHORTWAVE TROUGH WILL MOVE
THROUGH THE UPPER MIDWEST. WEAK CAA IS EXPECTED WITH THIS FEATURE
WHICH WILL HELP TO MAINTAIN CLOUD COVER.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
SHORTWAVE TROUGH WILL SWING THROUGH TONIGHT. PRECIP IS NOT
EXPECTED...BUT AGAIN CLOUD COVER WILL BE MAINTAINED WITH THE UPPER
LEVEL SYSTEM.

MODELS ARE SHOWING SOME IMPROVEMENT SUNDAY...PARTICULARLY OVER THE
WEST AND FAR SOUTH. HOWEVER...MODEL SOUNDINGS FOR THE REST OF THE
REGION STILL WANT TO MAINTAIN A SATURATED LAYER AROUND 2500FT FOR
MOST OF THE DAY...WHICH DOES NOT PRESENT MUCH HOPE FOR SUNSHINE.
CLOUDS WILL BE TRICKY ON SUNDAY...TRYING TO DETERMINE HOW MUCH OF
THE STRAOCU DECK WILL BE ERODED.

SPLIT FLOW DEVELOPS ON MONDAY WITH A LARGE SYSTEM TO THE WEST AND
ANOTHER SYSTEM TO THE SOUTH-SOUTHEAST. IT APPEARS THAT THE AREA
WILL LIE IN BETWEEN LIMITING THE CHANCES FOR PRECIPITATION. WAA
WILL CONTINUE ON MONDAY AND LOW-LEVEL MOISTURE INCREASES ONCE
AGAIN. LOOKS LIKE A GOOD DEAL OF CLOUD COVER AGAIN MONDAY. A WEAK
AND UNORGANIZED SHORTWAVE TROUGH WILL SWING THROUGH MONDAY...
ALLOWING FOR THE POSSIBILITY OF SOME LIGHT PRECIP...MAINLY OVER
THE SOUTHERN RIDGES. THIS WILL NEED TO BE FINE TUNED AS THE WARMER
AIR ALOFT MAY OCCUR BEFORE SURFACE TEMPS RESPOND. CONFIDENCE IS
LOW THAT ANY PRECIP WILL OCCUR...SO FOR FORECAST WILL LEAVE OUT.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
STILL SEEING SOME MINOR DIFFERENCES IN MEDIUM RANGE MODEL
SOLUTIONS FOR MIDWEEK SYSTEM. THINK MUCH OF TUESDAY COULD BE DRY
OR JUST LIGHT SHOWERS AS AREA WILL BE WELL INTO THE WARM SECTOR. RAIN
WILL OVERSPREAD THE AREA TUESDAY NIGHT AHEAD OF OCCLUDED FRONT AND
CONTINUE THROUGH WEDNESDAY. COLDER AIR WILL MOVE IN LATER
WEDNESDAY NIGHT CHANGING ANY LINGERING SHOWERS TO SNOW SHOWERS.
COULD SEE A BRIEF UPTICK IN SNOW SHOWER COVERAGE EARLY THURSDAY
MORNING AS MAIN TROUGH SWINGS THROUGH. COLD AIR WILL BE IN PLACE
THURSDAY...BUT WIND DIRECTION NOT OPTIMAL FOR LAKE INFLUENCED SNOW
SHOWERS.

WARMER AIR WILL MOVE BACK IN THURSDAY NIGHT AND FRIDAY.

&&

.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
LOW LEVEL MOISTURE WILL REMAIN TRAPPED UNDER A STRONG INVERSION
AOB 4KFT AS LOW LEVEL WINDS BECOME LIGHT....MAINTAINING HIGH MVFR
TO LOW VFR CONDITIONS OVER THE NEXT 24 HOURS. PRECIPITATION
CHANCES ARE MINIMAL GIVEN THE SHALLOW DEPTH OF THE SATURATED
LAYER AND ABSENCE OF ANY LIFT.

OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST THROUGH THE WEEKEND. NEXT STORM
SYSTEM WILL BEGIN TO IMPACT THE REGION ON TUESDAY AND RESULT IN
WIDESPREAD RAIN...CIG/VIS RESTRICTIONS...AND PERIODS OF LLWS
THROUGH WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$







000
FXUS61 KPBZ 200909
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
409 AM EST SAT DEC 20 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WEAK RIDGE BREAKS DOWN LATER TODAY AS SHORTWAVE TROUGH WILL MOVE
THROUGH THE UPPER MIDWEST. WEAK CAA IS EXPECTED WITH THIS FEATURE
WHICH WILL HELP TO MAINTAIN CLOUD COVER.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
SHORTWAVE TROUGH WILL SWING THROUGH TONIGHT. PRECIP IS NOT
EXPECTED...BUT AGAIN CLOUD COVER WILL BE MAINTAINED WITH THE UPPER
LEVEL SYSTEM.

MODELS ARE SHOWING SOME IMPROVEMENT SUNDAY...PARTICULARLY OVER THE
WEST AND FAR SOUTH. HOWEVER...MODEL SOUNDINGS FOR THE REST OF THE
REGION STILL WANT TO MAINTAIN A SATURATED LAYER AROUND 2500FT FOR
MOST OF THE DAY...WHICH DOES NOT PRESENT MUCH HOPE FOR SUNSHINE.
CLOUDS WILL BE TRICKY ON SUNDAY...TRYING TO DETERMINE HOW MUCH OF
THE STRAOCU DECK WILL BE ERODED.

SPLIT FLOW DEVELOPS ON MONDAY WITH A LARGE SYSTEM TO THE WEST AND
ANOTHER SYSTEM TO THE SOUTH-SOUTHEAST. IT APPEARS THAT THE AREA
WILL LIE IN BETWEEN LIMITING THE CHANCES FOR PRECIPITATION. WAA
WILL CONTINUE ON MONDAY AND LOW-LEVEL MOISTURE INCREASES ONCE
AGAIN. LOOKS LIKE A GOOD DEAL OF CLOUD COVER AGAIN MONDAY. A WEAK
AND UNORGANIZED SHORTWAVE TROUGH WILL SWING THROUGH MONDAY...
ALLOWING FOR THE POSSIBILITY OF SOME LIGHT PRECIP...MAINLY OVER
THE SOUTHERN RIDGES. THIS WILL NEED TO BE FINE TUNED AS THE WARMER
AIR ALOFT MAY OCCUR BEFORE SURFACE TEMPS RESPOND. CONFIDENCE IS
LOW THAT ANY PRECIP WILL OCCUR...SO FOR FORECAST WILL LEAVE OUT.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
STILL SEEING SOME MINOR DIFFERENCES IN MEDIUM RANGE MODEL
SOLUTIONS FOR MIDWEEK SYSTEM. THINK MUCH OF TUESDAY COULD BE DRY
OR JUST LIGHT SHOWERS AS AREA WILL BE WELL INTO THE WARM SECTOR. RAIN
WILL OVERSPREAD THE AREA TUESDAY NIGHT AHEAD OF OCCLUDED FRONT AND
CONTINUE THROUGH WEDNESDAY. COLDER AIR WILL MOVE IN LATER
WEDNESDAY NIGHT CHANGING ANY LINGERING SHOWERS TO SNOW SHOWERS.
COULD SEE A BRIEF UPTICK IN SNOW SHOWER COVERAGE EARLY THURSDAY
MORNING AS MAIN TROUGH SWINGS THROUGH. COLD AIR WILL BE IN PLACE
THURSDAY...BUT WIND DIRECTION NOT OPTIMAL FOR LAKE INFLUENCED SNOW
SHOWERS.

WARMER AIR WILL MOVE BACK IN THURSDAY NIGHT AND FRIDAY.

&&

.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
LOW LEVEL MOISTURE WILL REMAIN TRAPPED UNDER A STRONG INVERSION
AOB 4KFT AS LOW LEVEL WINDS BECOME LIGHT....MAINTAINING HIGH MVFR
TO LOW VFR CONDITIONS OVER THE NEXT 24 HOURS. PRECIPITATION
CHANCES ARE MINIMAL GIVEN THE SHALLOW DEPTH OF THE SATURATED
LAYER AND ABSENCE OF ANY LIFT.

OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST THROUGH THE WEEKEND. NEXT STORM
SYSTEM WILL BEGIN TO IMPACT THE REGION ON TUESDAY AND RESULT IN
WIDESPREAD RAIN...CIG/VIS RESTRICTIONS...AND PERIODS OF LLWS
THROUGH WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$






000
FXUS61 KPHI 200855
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
355 AM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER SOUTHWESTERN QUEBEC THIS MORNING WILL
DRIFT EASTWARD AND IT SHOULD REACH ATLANTIC CANADA ON MONDAY. WEAK
LOW PRESSURE IS FORECAST TO DEVELOP OFF THE CAROLINA COAST ON
MONDAY BEFORE MOVING SLOWLY NORTHEASTWARD AND DISSIPATING. STRONG
LOW PRESSURE IS EXPECTED TO LIFT NORTHWARD FROM THE LOWER
MISSISSIPPI RIVER VALLEY AND ACROSS THE GREAT LAKES DURING THE MID
WEEK PERIOD. THE LOW IS ANTICIPATED TO PULL A WARM FRONT THROUGH
OUR REGION ON WEDNESDAY, FOLLOWED BY A COLD FRONT ON WEDNESDAY
NIGHT. HIGH PRESSURE IS EXPECTED TO FOLLOW FROM THE SOUTHWEST FOR
THURSDAY AND FRIDAY. ANOTHER COLD FRONT IS FORECAST TO APPROACH
FROM THE WEST AND IT MAY ARRIVE ON SATURDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HIGH PRESSURE WILL CONTINUE TO BUILD ACROSS EASTERN CANADA AND
NORTHERN NEW ENGLAND TODAY, WITH THE MID-ATLANTIC BEING ON THE
SOUTHERN FRINGE. THIS WILL KEEP A DRY, LIGHT NORTHERLY FLOW ACROSS
THE AREA. WITH PW VALUES BETWEEN ONE-QUARTER AND ONE-THIRD OF AN
INCH, NO PRECIPITATION IS FORECAST. HOWEVER, THERE WILL REMAIN
MOISTURE CAUGHT UP UNDERNEATH THE INVERSION WHICH SHOULD KEEP SOME
CLOUD COVER ACROSS THE AREA. EVEN IF THE LOWER LEVEL CLOUDS
SCATTER OUT DURING THE DAY, WE SHOULD SEE AN INCREASE IN HIGH
LEVEL CLOUDS AS A SHORT WAVE/VORTICITY MAX SLIDES ACROSS THE AREA.
THE NORTHERLY WIND, ALONG WITH ANY CLOUD COVER SHOULD PREVENT
TEMPERATURES FROM WARMING SIGNIFICANTLY TODAY, SO WE USED A BLEND
OF MAV/MET MOS AND MOSGUIDE WHICH WERE IN PRETTY GOOD AGREEMENT.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/...
NOT MUCH OF A CHANGE TO THE FORECAST TONIGHT FROM THE DAY TIME.
HIGH PRESSURE, CENTERED ACROSS NORTHERN NEW ENGLAND AND EASTERN
CANADA REMAINS IN CONTROL OF THE WEATHER. WITH CONTINUING LOW PW
VALUES, NO PRECIPITATION IS EXPECTED. CLOUD COVER SHOULD REMAIN
ACROSS THE AREA, ESPECIALLY AS A SHORT WAVE/VORTICITY MAX SLIDES
TOWARD THE AREA OVERNIGHT.

OVERNIGHT LOWS WERE A BLEND OF MAV/MET MOS AND MOSGUIDE WHICH
WERE IN PRETTY GOOD AGREEMENT.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
A MID LEVEL SHORT WAVE THAT WAS LOCATED OVER WESTERN IOWA AND
VICINITY EARLY THIS MORNING WILL PROGRESS EASTWARD AND IT SHOULD
PASS OVER OUR REGION EARLY ON SUNDAY MORNING. WHILE WE ARE
ANTICIPATING SOME CLOUDS WITH THE SYSTEM THERE SHOULD NOT BE
ENOUGH MOISTURE TO PRODUCE ANY PRECIPITATION.

SURFACE HIGH PRESSURE IS FORECAST TO BE LOCATED OVER SOUTHERN
QUEBEC ON SUNDAY MORNING. THE CENTER OF THE HIGH SHOULD DRIFT
EASTWARD REACHING ATLANTIC CANADA ON MONDAY AND MONDAY NIGHT. A
RIDGE AXIS IS EXPECTED TO NOSE SOUTHWESTWARD ALONG THE LEE OF THE
APPALACHIANS AT THAT TIME WITH AN INVERTED TROUGH DEVELOPING OFF
THE COAST. WEAK LOW PRESSURE IS ANTICIPATED TO DEVELOP ON THE
TROUGH OFF THE CAROLINA COAST ON MONDAY. THE FEATURE IS FORECAST
TO REMAIN WEAK AS IT DRIFTS NORTHEASTWARD REACHING THE WATERS OFF
THE DELMARVA BEFORE DISSIPATING ON TUESDAY.

AREAS OF LIGHT PRECIPITATION ARE EXPECTED TO SPREAD SLOWLY
NORTHWARD INTO OUR REGION ON MONDAY AND THEY SHOULD REMAIN HERE
FOR MONDAY NIGHT AND TUESDAY. THE OVERALL TREND WILL BE TOWARD
WARMING TEMPERATURES. AS A RESULT, MOST OF THE PRECIPITATION IS
ANTICIPATED TO BE IN THE FORM OF RAIN. HOWEVER, POCKETS OF BELOW
FREEZING TEMPERATURES MAY LINGER IN THE POCONOS ON MONDAY NIGHT
INTO EARLY TUESDAY MORNING SO WE HAVE MENTIONED A CHANCE OF
FREEZING RAIN THERE.

OUR MAIN WEATHER FEATURE FOR THE COMING WEEK IS THE DEEP MID
LEVEL TROUGH THAT IS FORECAST TO DIG OVER THE MIDDLE PART OF THE
COUNTRY ON MONDAY AND TUESDAY. THE TROUGH IS EXPECTED TO LIFT
NORTHEASTWARD AND ITS AXIS SHOULD PASS OVERHEAD EARLY ON THURSDAY.

SURFACE LOW PRESSURE IS ANTICIPATED TO DEVELOP OVER THE LOWER
MISSISSIPPI RIVER VALLEY ON TUESDAY IN RESPONSE TO THE TROUGH. THE
LOW IS FORECAST TO STRENGTHEN AS IT MOVES ACROSS THE GREAT LAKES
ON WEDNESDAY AND WEDNESDAY NIGHT. THE SYSTEM SHOULD HAVE AN
OPPORTUNITY TO TAP INTO GULF MOISTURE AND IT WILL BRING THE
POTENTIAL FOR SOME MODERATE TO HEAVY RAINFALL TO OUR REGION FROM
WEDNESDAY INTO EARLY WEDNESDAY NIGHT.

THE LOW IS EXPECTED TO PULL A WARM FRONT THROUGH OUR REGION ON
WEDNESDAY WITH TEMPERATURES FORECAST TO RISE INTO THE 50S AT MOST
LOCATIONS. SOME 60 DEGREE READINGS ARE POSSIBLE ON THE DELMARVA
AND PERHAPS IN FAR SOUTHERN NEW JERSEY. CONDITIONS MAY BECOME
QUITE BREEZY IN THE WARM SECTOR WHERE THE ATMOSPHERE SHOULD MIX
RATHER EFFICIENTLY. A STRONG COLD FRONT IS FORECAST TO FOLLOW ON
WEDNESDAY NIGHT WITH TEMPERATURES DROPPING BACK INTO THE 30S BY
DAYBREAK ON THURSDAY. THE PROBABILITY OF PRECIPITATION DECREASES
RAPIDLY ON WEDNESDAY NIGHT AS DRY AIR IS EXPECTED TO BUILD INTO
OUR REGION FROM THE SOUTHWEST.

RIDGING IS FORECAST TO DEVELOP AT THE SURFACE AND ALOFT FOR
THURSDAY INTO FRIDAY WITH MAINLY DRY WEATHER AND SEASONABLE
TEMPERATURES ANTICIPATED.

A MID LEVEL SHORT WAVE MAY APPROACH FROM THE WEST ON SATURDAY
ALONG WITH AN ASSOCIATED SURFACE COLD FRONT. THE GUIDANCE DIFFERS
A BIT ON THE TIMING OF THE FEATURE AT THIS POINT AS WELL ON THE
AMOUNT OF MOISTURE ASSOCIATED WITH THE SYSTEM.

&&

.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

MOST OF THE TAF SITES ARE NOW MVFR, EXCEPT PHL/ILG/MIV, ALTHOUGH
THEY SHOULD BE THERE SHORTLY. THE MVFR CIGS WILL CONTINUE ACROSS
THE TAF SITES THROUGH THIS MORNING AS MOISTURE REMAINS TRAPPED
UNDERNEATH THE INVERSION. CLOUDS MAY SCATTER OUT DURING THE DAY
WITH HIGHER LEVEL CLOUDS OVERHEAD, LEADING TO VFR CONDITIONS FOR
THE REMAINDER OF THE PERIOD. IF THE CLOUDS DO NOT BEGIN TO SCATTER
OUT BY MIDDAY, IT`S POSSIBLE WE COULD SEE AN EXTENDED PERIOD OF
MVFR CIGS THROUGH THE DAY INTO TONIGHT.

NORTHERLY WINDS WILL BE LIGHT, GENERALLY AROUND 5-10 KNOTS OR
LESS THROUGH THE DAY. SOME NORTHWEST TO WEST WINDS ARE POSSIBLE
EARLY, BUT SHOULD BECOME MORE NORTHERLY DURING THE DAY. EVERYONE
IS EXPECTED TO BECOME LIGHT AND VARIABLE/CALM LATER THIS AFTERNOON
INTO THE EVENING/OVERNIGHT.

OUTLOOK...
SUNDAY AND SUNDAY NIGHT...MAINLY VFR.

MONDAY...MAINLY VFR WITH A CHANCE OF LIGHT RAIN SPREADING
NORTHWARD INTO OUR REGION.

MONDAY NIGHT AND TUESDAY...CONDITIONS POSSIBLY LOWERING INTO THE
MVFR CATEGORY WITH A CHANCE OF LIGHT RAIN.

TUESDAY NIGHT...MVFR AND IFR CONDITIONS ANTICIPATED WITH RAIN
LIKELY.

WEDNESDAY...MVFR AND IFR CONDITIONS WITH RAIN LIKELY. THE RAIN
MAY BE HEAVY AT TIMES. A GUSTY SOUTH WIND MAY DEVELOP, ESPECIALLY
IN THE AFTERNOON.

&&

.MARINE...
SUB-SMALL CRAFT ADVISORY CONDITIONS WILL REMAIN TODAY INTO
TONIGHT AS HIGH PRESSURE FROM THE NORTH WILL AFFECT THE WATERS.

OUTLOOK...
SUNDAY THROUGH MONDAY NIGHT...NO MARINE HEADLINES ARE
ANTICIPATED.

TUESDAY AND TUESDAY NIGHT...WAVE HEIGHTS ON OUR OCEAN WATERS MAY
BUILD TO 5 TO 6 FEET IN A DEVELOPING ONSHORE FLOW.

WEDNESDAY...SOUTHERLY WIND GUSTS IN EXCESS OF 25 KNOTS ARE
EXPECTED. WAVE HEIGHTS ON OUR OCEAN WATERS MAY BUILD TO 6 TO 9
FEET IN A STRONG SOUTHERLY FLOW.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...IOVINO
NEAR TERM...ROBERTSON
SHORT TERM...ROBERTSON
LONG TERM...IOVINO
AVIATION...IOVINO/ROBERTSON
MARINE...IOVINO/ROBERTSON






000
FXUS61 KPHI 200855
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
355 AM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER SOUTHWESTERN QUEBEC THIS MORNING WILL
DRIFT EASTWARD AND IT SHOULD REACH ATLANTIC CANADA ON MONDAY. WEAK
LOW PRESSURE IS FORECAST TO DEVELOP OFF THE CAROLINA COAST ON
MONDAY BEFORE MOVING SLOWLY NORTHEASTWARD AND DISSIPATING. STRONG
LOW PRESSURE IS EXPECTED TO LIFT NORTHWARD FROM THE LOWER
MISSISSIPPI RIVER VALLEY AND ACROSS THE GREAT LAKES DURING THE MID
WEEK PERIOD. THE LOW IS ANTICIPATED TO PULL A WARM FRONT THROUGH
OUR REGION ON WEDNESDAY, FOLLOWED BY A COLD FRONT ON WEDNESDAY
NIGHT. HIGH PRESSURE IS EXPECTED TO FOLLOW FROM THE SOUTHWEST FOR
THURSDAY AND FRIDAY. ANOTHER COLD FRONT IS FORECAST TO APPROACH
FROM THE WEST AND IT MAY ARRIVE ON SATURDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HIGH PRESSURE WILL CONTINUE TO BUILD ACROSS EASTERN CANADA AND
NORTHERN NEW ENGLAND TODAY, WITH THE MID-ATLANTIC BEING ON THE
SOUTHERN FRINGE. THIS WILL KEEP A DRY, LIGHT NORTHERLY FLOW ACROSS
THE AREA. WITH PW VALUES BETWEEN ONE-QUARTER AND ONE-THIRD OF AN
INCH, NO PRECIPITATION IS FORECAST. HOWEVER, THERE WILL REMAIN
MOISTURE CAUGHT UP UNDERNEATH THE INVERSION WHICH SHOULD KEEP SOME
CLOUD COVER ACROSS THE AREA. EVEN IF THE LOWER LEVEL CLOUDS
SCATTER OUT DURING THE DAY, WE SHOULD SEE AN INCREASE IN HIGH
LEVEL CLOUDS AS A SHORT WAVE/VORTICITY MAX SLIDES ACROSS THE AREA.
THE NORTHERLY WIND, ALONG WITH ANY CLOUD COVER SHOULD PREVENT
TEMPERATURES FROM WARMING SIGNIFICANTLY TODAY, SO WE USED A BLEND
OF MAV/MET MOS AND MOSGUIDE WHICH WERE IN PRETTY GOOD AGREEMENT.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/...
NOT MUCH OF A CHANGE TO THE FORECAST TONIGHT FROM THE DAY TIME.
HIGH PRESSURE, CENTERED ACROSS NORTHERN NEW ENGLAND AND EASTERN
CANADA REMAINS IN CONTROL OF THE WEATHER. WITH CONTINUING LOW PW
VALUES, NO PRECIPITATION IS EXPECTED. CLOUD COVER SHOULD REMAIN
ACROSS THE AREA, ESPECIALLY AS A SHORT WAVE/VORTICITY MAX SLIDES
TOWARD THE AREA OVERNIGHT.

OVERNIGHT LOWS WERE A BLEND OF MAV/MET MOS AND MOSGUIDE WHICH
WERE IN PRETTY GOOD AGREEMENT.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
A MID LEVEL SHORT WAVE THAT WAS LOCATED OVER WESTERN IOWA AND
VICINITY EARLY THIS MORNING WILL PROGRESS EASTWARD AND IT SHOULD
PASS OVER OUR REGION EARLY ON SUNDAY MORNING. WHILE WE ARE
ANTICIPATING SOME CLOUDS WITH THE SYSTEM THERE SHOULD NOT BE
ENOUGH MOISTURE TO PRODUCE ANY PRECIPITATION.

SURFACE HIGH PRESSURE IS FORECAST TO BE LOCATED OVER SOUTHERN
QUEBEC ON SUNDAY MORNING. THE CENTER OF THE HIGH SHOULD DRIFT
EASTWARD REACHING ATLANTIC CANADA ON MONDAY AND MONDAY NIGHT. A
RIDGE AXIS IS EXPECTED TO NOSE SOUTHWESTWARD ALONG THE LEE OF THE
APPALACHIANS AT THAT TIME WITH AN INVERTED TROUGH DEVELOPING OFF
THE COAST. WEAK LOW PRESSURE IS ANTICIPATED TO DEVELOP ON THE
TROUGH OFF THE CAROLINA COAST ON MONDAY. THE FEATURE IS FORECAST
TO REMAIN WEAK AS IT DRIFTS NORTHEASTWARD REACHING THE WATERS OFF
THE DELMARVA BEFORE DISSIPATING ON TUESDAY.

AREAS OF LIGHT PRECIPITATION ARE EXPECTED TO SPREAD SLOWLY
NORTHWARD INTO OUR REGION ON MONDAY AND THEY SHOULD REMAIN HERE
FOR MONDAY NIGHT AND TUESDAY. THE OVERALL TREND WILL BE TOWARD
WARMING TEMPERATURES. AS A RESULT, MOST OF THE PRECIPITATION IS
ANTICIPATED TO BE IN THE FORM OF RAIN. HOWEVER, POCKETS OF BELOW
FREEZING TEMPERATURES MAY LINGER IN THE POCONOS ON MONDAY NIGHT
INTO EARLY TUESDAY MORNING SO WE HAVE MENTIONED A CHANCE OF
FREEZING RAIN THERE.

OUR MAIN WEATHER FEATURE FOR THE COMING WEEK IS THE DEEP MID
LEVEL TROUGH THAT IS FORECAST TO DIG OVER THE MIDDLE PART OF THE
COUNTRY ON MONDAY AND TUESDAY. THE TROUGH IS EXPECTED TO LIFT
NORTHEASTWARD AND ITS AXIS SHOULD PASS OVERHEAD EARLY ON THURSDAY.

SURFACE LOW PRESSURE IS ANTICIPATED TO DEVELOP OVER THE LOWER
MISSISSIPPI RIVER VALLEY ON TUESDAY IN RESPONSE TO THE TROUGH. THE
LOW IS FORECAST TO STRENGTHEN AS IT MOVES ACROSS THE GREAT LAKES
ON WEDNESDAY AND WEDNESDAY NIGHT. THE SYSTEM SHOULD HAVE AN
OPPORTUNITY TO TAP INTO GULF MOISTURE AND IT WILL BRING THE
POTENTIAL FOR SOME MODERATE TO HEAVY RAINFALL TO OUR REGION FROM
WEDNESDAY INTO EARLY WEDNESDAY NIGHT.

THE LOW IS EXPECTED TO PULL A WARM FRONT THROUGH OUR REGION ON
WEDNESDAY WITH TEMPERATURES FORECAST TO RISE INTO THE 50S AT MOST
LOCATIONS. SOME 60 DEGREE READINGS ARE POSSIBLE ON THE DELMARVA
AND PERHAPS IN FAR SOUTHERN NEW JERSEY. CONDITIONS MAY BECOME
QUITE BREEZY IN THE WARM SECTOR WHERE THE ATMOSPHERE SHOULD MIX
RATHER EFFICIENTLY. A STRONG COLD FRONT IS FORECAST TO FOLLOW ON
WEDNESDAY NIGHT WITH TEMPERATURES DROPPING BACK INTO THE 30S BY
DAYBREAK ON THURSDAY. THE PROBABILITY OF PRECIPITATION DECREASES
RAPIDLY ON WEDNESDAY NIGHT AS DRY AIR IS EXPECTED TO BUILD INTO
OUR REGION FROM THE SOUTHWEST.

RIDGING IS FORECAST TO DEVELOP AT THE SURFACE AND ALOFT FOR
THURSDAY INTO FRIDAY WITH MAINLY DRY WEATHER AND SEASONABLE
TEMPERATURES ANTICIPATED.

A MID LEVEL SHORT WAVE MAY APPROACH FROM THE WEST ON SATURDAY
ALONG WITH AN ASSOCIATED SURFACE COLD FRONT. THE GUIDANCE DIFFERS
A BIT ON THE TIMING OF THE FEATURE AT THIS POINT AS WELL ON THE
AMOUNT OF MOISTURE ASSOCIATED WITH THE SYSTEM.

&&

.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

MOST OF THE TAF SITES ARE NOW MVFR, EXCEPT PHL/ILG/MIV, ALTHOUGH
THEY SHOULD BE THERE SHORTLY. THE MVFR CIGS WILL CONTINUE ACROSS
THE TAF SITES THROUGH THIS MORNING AS MOISTURE REMAINS TRAPPED
UNDERNEATH THE INVERSION. CLOUDS MAY SCATTER OUT DURING THE DAY
WITH HIGHER LEVEL CLOUDS OVERHEAD, LEADING TO VFR CONDITIONS FOR
THE REMAINDER OF THE PERIOD. IF THE CLOUDS DO NOT BEGIN TO SCATTER
OUT BY MIDDAY, IT`S POSSIBLE WE COULD SEE AN EXTENDED PERIOD OF
MVFR CIGS THROUGH THE DAY INTO TONIGHT.

NORTHERLY WINDS WILL BE LIGHT, GENERALLY AROUND 5-10 KNOTS OR
LESS THROUGH THE DAY. SOME NORTHWEST TO WEST WINDS ARE POSSIBLE
EARLY, BUT SHOULD BECOME MORE NORTHERLY DURING THE DAY. EVERYONE
IS EXPECTED TO BECOME LIGHT AND VARIABLE/CALM LATER THIS AFTERNOON
INTO THE EVENING/OVERNIGHT.

OUTLOOK...
SUNDAY AND SUNDAY NIGHT...MAINLY VFR.

MONDAY...MAINLY VFR WITH A CHANCE OF LIGHT RAIN SPREADING
NORTHWARD INTO OUR REGION.

MONDAY NIGHT AND TUESDAY...CONDITIONS POSSIBLY LOWERING INTO THE
MVFR CATEGORY WITH A CHANCE OF LIGHT RAIN.

TUESDAY NIGHT...MVFR AND IFR CONDITIONS ANTICIPATED WITH RAIN
LIKELY.

WEDNESDAY...MVFR AND IFR CONDITIONS WITH RAIN LIKELY. THE RAIN
MAY BE HEAVY AT TIMES. A GUSTY SOUTH WIND MAY DEVELOP, ESPECIALLY
IN THE AFTERNOON.

&&

.MARINE...
SUB-SMALL CRAFT ADVISORY CONDITIONS WILL REMAIN TODAY INTO
TONIGHT AS HIGH PRESSURE FROM THE NORTH WILL AFFECT THE WATERS.

OUTLOOK...
SUNDAY THROUGH MONDAY NIGHT...NO MARINE HEADLINES ARE
ANTICIPATED.

TUESDAY AND TUESDAY NIGHT...WAVE HEIGHTS ON OUR OCEAN WATERS MAY
BUILD TO 5 TO 6 FEET IN A DEVELOPING ONSHORE FLOW.

WEDNESDAY...SOUTHERLY WIND GUSTS IN EXCESS OF 25 KNOTS ARE
EXPECTED. WAVE HEIGHTS ON OUR OCEAN WATERS MAY BUILD TO 6 TO 9
FEET IN A STRONG SOUTHERLY FLOW.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...IOVINO
NEAR TERM...ROBERTSON
SHORT TERM...ROBERTSON
LONG TERM...IOVINO
AVIATION...IOVINO/ROBERTSON
MARINE...IOVINO/ROBERTSON







000
FXUS61 KCTP 200636
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
136 AM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER THE WESTERN GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND...BRINGING DRY WEATHER WITH
LIGHTER WIND. A DEEP UPPER TROUGH AND ASSOCIATED SFC LOW WILL LIFT
NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE OF NEXT WEEK
LIKELY BRINGING US RAIN AND WIND FOR CHRISTMAS EVE...THEN BLUSTERY
AND COLDER CONDITIONS FOR CHRISTMAS DAY WITH SCATTERED SNOW
SHOWERS.

&&

.NEAR TERM /UNTIL 8 AM THIS MORNING/...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK TRAPPED BELOW A
MODERATELY STRONG SUBSIDENCE INVERSION /BASED AT AROUND 2-3KFT
AGL/ WILL PERSIST ACROSS MUCH OF CENTRAL PENNSYLVANIA EARLY THIS
MORNING. APPROACH OF SFC HIGH AND FALLING INVERSION HGT HAS
RESULTED IN PARTIAL CLEARING ACROSS THE SC MTNS AND NR TERM MDL
SOUNDINGS INDICATE THIS AREA WILL REMAIN MCLEAR THRU DAWN...WHILE
STRATOCU PERSISTS ELSEWHERE. TEMPS ON TRACK TO BOTTOM OUT IN THE
20S.

&&

.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM SUNDAY/...
A RIDGE OF HIGH PRESSURE...LIGHTER WIND...AND ASSOC DRIER AIR
MASS WILL BUILD EAST ACROSS THE STATE SATURDAY...PROVIDING THE
AREA WITH FAIR WEATHER.

HIGH RES MODEL DATA CONTINUES TO PAINT A MOSTLY CLOUDY PICTURE FOR
MUCH OF THE REGION SATURDAY INTO SATURDAY NIGHT...THOUGH PERIODS
OF SUNSHINE ARE LIKELY THROUGHOUT THE CENTRAL RIDGE AND VALLEY
REGION...AND SUSQUEHANNA RIVER VALLEY.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS OVER THE LOWER/THIN STRATO CU
CLOUD DECK PRESENT ACROSS THE REGION SATURDAY. ALL 12Z OPERATIONAL
MODEL DATA CONTINUES TO SUPPORT A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS NEAR 30 ACROSS THE MTNS...AND MID TO UPPER 30S IN
THE SE.

MOSTLY CLOUDY SKIES WITH LIGHT WIND SAT NIGHT WILL YIELD LOWS IN
THE LOWER 20S ACROSS THE MTNS...AND GENERALLY THE MID 20S
ELSEWHERE.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
HIGH PRES WILL PROVIDE TRANQUIL WEATHER ON SUNDAY...WITH PARTLY TO
MOSTLY SUNNY SKIES AND SEASONABLE TEMPS. AFTER THAT...THE WEATHER
WILL BECOME INCREASINGLY UNSETTLED AS NEXT WEEK PROGRESSES.

CLOUDS WILL INCR SUNDAY NIGHT INTO MONDAY...AS HIGH PRES LOSES
ITS GRIP AND A WEAK AREA OF LOW PRES ORGANIZES OVER THE SERN UNITED
STATES. LIGHT PRECIP WILL WORK NWD INTO PENNSYLVANIA LATE MONDAY
INTO MONDAY NIGHT AND CONTINUE INTO TUES. INITIALLY...CONDS WILL
BE COLD ENOUGH FOR THE POSSIBILITY OF SOME WINTRY PRECIP.
HOWEVER...WARMER AIR WILL MAKE ITS WAY NWD LATER MONDAY NIGHT INTO
TUES AND GRADUALLY CHANGE ANY LINGERING PRECIP OVER TO PLAIN RAIN.

A MORE SIGNIFICANT STORM SYSTEM WILL GET ORGANIZED OVER THE
MISSISSIPPI VALLEY TUES NIGHT BEFORE PUSHING NWD INTO THE GREAT
LAKES ON WED. THIS SYSTEM WILL DRAW EVEN MILDER AIR NWD INTO THE
REGION...AND PROVIDE A RAINY AND BREEZY CHRISTMAS EVE DAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS FROM WEST TO EAST ACROSS PA IS POSSIBLE LATE WED/WED
NIGHT. SCT SNOW SHOWERS WILL CONTINUE INTO THURS ACROSS MAINLY
NRN AND WRN PA.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
OPERATIONAL MODELS AND THE GEFS SHOWING 850HPA TEMPS ALREADY
BEGINNING TO RISE NEXT FRI.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
NORTHWESTERLY SFC FLOW THAT HAS CAUSED OROGRAPHIC FORCING OF A
SHALLOW MOIST LAYER WILL CONTINUE TO PRODUCE PLENTY OF CLOUDS
ACROSS THE NW AND THE LAURELS WITH MAINLY MVFR BKN-OVC CIGS
THROUGH TONIGHT. KJST AND KBFD WILL TREND IFR THROUGH 12Z...AND
CIGS WILL SLOWLY INCREASE AS THE LOW LEVELS DRY OUT BY MID TO LATE
TOMORROW MORNING. IN CONTRAST...THE SE PENN AIRFIELDS SUCH AS
KMDT...KTHV AND KLNS WILL SEE MAINLY VFR.

NORTHWEST WINDS OF 10-15 KTS WITH HIGHER GUSTS WILL DECREASE TO 8
KTS OR LESS LATER TONIGHT AND SATURDAY.

HIGH PRESSURE BUILDS EAST ACROSS PENN SATURDAY...WITH BKN-OVC CIGS
VARYING BETWEEN MVFR OVER THE HIGHER TERRAIN OF THE NORTH AND
WEST...TO SCT-BKN VFR IN THE VALLEYS.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...FITZGERALD
SHORT TERM...LAMBERT
LONG TERM...EVANEGO
AVIATION...LAMBERT/CERU



000
FXUS61 KCTP 200636
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
136 AM EST SAT DEC 20 2014

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER THE WESTERN GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND...BRINGING DRY WEATHER WITH
LIGHTER WIND. A DEEP UPPER TROUGH AND ASSOCIATED SFC LOW WILL LIFT
NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE OF NEXT WEEK
LIKELY BRINGING US RAIN AND WIND FOR CHRISTMAS EVE...THEN BLUSTERY
AND COLDER CONDITIONS FOR CHRISTMAS DAY WITH SCATTERED SNOW
SHOWERS.

&&

.NEAR TERM /UNTIL 8 AM THIS MORNING/...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK TRAPPED BELOW A
MODERATELY STRONG SUBSIDENCE INVERSION /BASED AT AROUND 2-3KFT
AGL/ WILL PERSIST ACROSS MUCH OF CENTRAL PENNSYLVANIA EARLY THIS
MORNING. APPROACH OF SFC HIGH AND FALLING INVERSION HGT HAS
RESULTED IN PARTIAL CLEARING ACROSS THE SC MTNS AND NR TERM MDL
SOUNDINGS INDICATE THIS AREA WILL REMAIN MCLEAR THRU DAWN...WHILE
STRATOCU PERSISTS ELSEWHERE. TEMPS ON TRACK TO BOTTOM OUT IN THE
20S.

&&

.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM SUNDAY/...
A RIDGE OF HIGH PRESSURE...LIGHTER WIND...AND ASSOC DRIER AIR
MASS WILL BUILD EAST ACROSS THE STATE SATURDAY...PROVIDING THE
AREA WITH FAIR WEATHER.

HIGH RES MODEL DATA CONTINUES TO PAINT A MOSTLY CLOUDY PICTURE FOR
MUCH OF THE REGION SATURDAY INTO SATURDAY NIGHT...THOUGH PERIODS
OF SUNSHINE ARE LIKELY THROUGHOUT THE CENTRAL RIDGE AND VALLEY
REGION...AND SUSQUEHANNA RIVER VALLEY.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS OVER THE LOWER/THIN STRATO CU
CLOUD DECK PRESENT ACROSS THE REGION SATURDAY. ALL 12Z OPERATIONAL
MODEL DATA CONTINUES TO SUPPORT A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS NEAR 30 ACROSS THE MTNS...AND MID TO UPPER 30S IN
THE SE.

MOSTLY CLOUDY SKIES WITH LIGHT WIND SAT NIGHT WILL YIELD LOWS IN
THE LOWER 20S ACROSS THE MTNS...AND GENERALLY THE MID 20S
ELSEWHERE.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
HIGH PRES WILL PROVIDE TRANQUIL WEATHER ON SUNDAY...WITH PARTLY TO
MOSTLY SUNNY SKIES AND SEASONABLE TEMPS. AFTER THAT...THE WEATHER
WILL BECOME INCREASINGLY UNSETTLED AS NEXT WEEK PROGRESSES.

CLOUDS WILL INCR SUNDAY NIGHT INTO MONDAY...AS HIGH PRES LOSES
ITS GRIP AND A WEAK AREA OF LOW PRES ORGANIZES OVER THE SERN UNITED
STATES. LIGHT PRECIP WILL WORK NWD INTO PENNSYLVANIA LATE MONDAY
INTO MONDAY NIGHT AND CONTINUE INTO TUES. INITIALLY...CONDS WILL
BE COLD ENOUGH FOR THE POSSIBILITY OF SOME WINTRY PRECIP.
HOWEVER...WARMER AIR WILL MAKE ITS WAY NWD LATER MONDAY NIGHT INTO
TUES AND GRADUALLY CHANGE ANY LINGERING PRECIP OVER TO PLAIN RAIN.

A MORE SIGNIFICANT STORM SYSTEM WILL GET ORGANIZED OVER THE
MISSISSIPPI VALLEY TUES NIGHT BEFORE PUSHING NWD INTO THE GREAT
LAKES ON WED. THIS SYSTEM WILL DRAW EVEN MILDER AIR NWD INTO THE
REGION...AND PROVIDE A RAINY AND BREEZY CHRISTMAS EVE DAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS FROM WEST TO EAST ACROSS PA IS POSSIBLE LATE WED/WED
NIGHT. SCT SNOW SHOWERS WILL CONTINUE INTO THURS ACROSS MAINLY
NRN AND WRN PA.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
OPERATIONAL MODELS AND THE GEFS SHOWING 850HPA TEMPS ALREADY
BEGINNING TO RISE NEXT FRI.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
NORTHWESTERLY SFC FLOW THAT HAS CAUSED OROGRAPHIC FORCING OF A
SHALLOW MOIST LAYER WILL CONTINUE TO PRODUCE PLENTY OF CLOUDS
ACROSS THE NW AND THE LAURELS WITH MAINLY MVFR BKN-OVC CIGS
THROUGH TONIGHT. KJST AND KBFD WILL TREND IFR THROUGH 12Z...AND
CIGS WILL SLOWLY INCREASE AS THE LOW LEVELS DRY OUT BY MID TO LATE
TOMORROW MORNING. IN CONTRAST...THE SE PENN AIRFIELDS SUCH AS
KMDT...KTHV AND KLNS WILL SEE MAINLY VFR.

NORTHWEST WINDS OF 10-15 KTS WITH HIGHER GUSTS WILL DECREASE TO 8
KTS OR LESS LATER TONIGHT AND SATURDAY.

HIGH PRESSURE BUILDS EAST ACROSS PENN SATURDAY...WITH BKN-OVC CIGS
VARYING BETWEEN MVFR OVER THE HIGHER TERRAIN OF THE NORTH AND
WEST...TO SCT-BKN VFR IN THE VALLEYS.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...FITZGERALD
SHORT TERM...LAMBERT
LONG TERM...EVANEGO
AVIATION...LAMBERT/CERU




000
FXUS61 KPBZ 200614
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
114 AM EST SAT DEC 20 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /THROUGH TODAY/...
OVERNIGHT PERIOD IN GOOD SHAPE. STRATOCU REMAINS TRAPPED UNDER
WEAK RIDGE. TEMPS HAVE BEEN ADJUSTED TO LATEST GUIDANCE.

WEAK RIDGE BREAKS DOWN LATER TODAY AS SHORTWAVE TROUGH WILL MOVE
THROUGH THE UPPER MIDWEST. WEAK CAA IS EXPECTED WITH THIS FEATURE
WHICH WILL HELP TO MAINTAIN CLOUD COVER.

&&

.SHORT TERM /TONIGHT THROUGH MONDAY/...
SHORTWAVE TROUGH WILL SWING THROUGH TONIGHT. PRECIP IS NOT
EXPECTED...BUT AGAIN CLOUD COVER WILL BE MAINTAINED WITH THE UPPER
LEVEL SYSTEM.

MODELS ARE SHOWING SOME IMPROVEMENT SUNDAY...PARTICULARLY OVER THE
WEST AND FAR SOUTH. HOWEVER...MODEL SOUNDINGS FOR THE REST OF THE
REGION STILL WANT TO MAINTAIN A SATURATED LAYER AROUND 2500FT FOR
MOST OF THE DAY...WHICH DOES NOT PRESENT MUCH HOPE FOR SUNSHINE.
CLOUDS WILL BE TRICKY ON SUNDAY...TRYING TO DETERMINE HOW MUCH OF
THE STRAOCU DECK WILL BE ERODED.

SPLIT FLOW DEVELOPS ON MONDAY WITH A LARGE SYSTEM TO THE WEST AND
ANOTHER SYSTEM TO THE SOUTH-SOUTHEAST. IT APPEARS THAT THE AREA
WILL LIE IN BETWEEN LIMITING THE CHANCES FOR PRECIPITATION. WAA
WILL CONTINUE ON MONDAY AND LOW-LEVEL MOISTURE INCREASES ONCE
AGAIN. LOOKS LIKE A GOOD DEAL OF CLOUD COVER AGAIN MONDAY. A WEAK
AND UNORGANIZED SHORTWAVE TROUGH WILL SWING THROUGH
MONDAY...ALLOWING FOR THE POSSIBILITY OF SOME LIGHT PRECIP...MAINLY
OVER THE SOUTHERN RIDGES. THIS WILL NEED TO BE FINE TUNED AS THE
WARMER AIR ALOFT MAY OCCUR BEFORE SURFACE TEMPS RESPOND. TIMING OF
THE PRECIP WILL BE CRITICAL TO PROVIDING TIME FOR SURFACE TEMPS IN
THE SOUTHERN RIDGES TO RISE. FOR NOW WILL MENTION A CHANCE FOR
FREEZING RAIN IN THE SOUTHERN RIDGES...BUT CONFIDENCE IS LOW.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
STILL SEEING SOME MINOR DIFFERENCES IN MEDIUM RANGE MODEL
SOLUTIONS FOR MIDWEEK SYSTEM. THINK MUCH OF TUESDAY COULD BE DRY
OR JUST LIGHT SHOWERS AS AREA WILL BE WELL INTO THE WARM SECTOR. RAIN
WILL OVERSPREAD THE AREA TUESDAY NIGHT AHEAD OF OCCLUDED FRONT AND
CONTINUE THROUGH WEDNESDAY. COLDER AIR WILL MOVE IN LATER
WEDNESDAY NIGHT CHANGING ANY LINGERING SHOWERS TO SNOW SHOWERS.
COULD SEE A BRIEF UPTICK IN SNOW SHOWER COVERAGE EARLY THURSDAY
MORNING AS MAIN TROUGH SWINGS THROUGH. COLD AIR WILL BE IN PLACE
THURSDAY...BUT WIND DIRECTION NOT OPTIMAL FOR LAKE INFLUENCED SNOW
SHOWERS.

WARMER AIR WILL MOVE BACK IN THURSDAY NIGHT AND FRIDAY.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
LOW LEVEL MOISTURE WILL REMAIN TRAPPED UNDER A STRONG INVERSION
AOB 4KFT AS LOW LEVEL WINDS BECOME LIGHT....MAINTAINING HIGH MVFR
TO LOW VFR CONDITIONS OVER THE NEXT 24 HOURS. PRECIPITATION
CHANCES ARE MINIMAL GIVEN THE SHALLOW DEPTH OF THE SATURATED
LAYER AND ABSENCE OF ANY LIFT.

OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST THROUGH THE WEEKEND. NEXT STORM
SYSTEM WILL BEGIN TO IMPACT THE REGION ON TUESDAY AND RESULT IN
WIDESPREAD RAIN...CIG/VIS RESTRICTIONS...AND PERIODS OF LLWS
THROUGH WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$






000
FXUS61 KPBZ 200614
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
114 AM EST SAT DEC 20 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /THROUGH TODAY/...
OVERNIGHT PERIOD IN GOOD SHAPE. STRATOCU REMAINS TRAPPED UNDER
WEAK RIDGE. TEMPS HAVE BEEN ADJUSTED TO LATEST GUIDANCE.

WEAK RIDGE BREAKS DOWN LATER TODAY AS SHORTWAVE TROUGH WILL MOVE
THROUGH THE UPPER MIDWEST. WEAK CAA IS EXPECTED WITH THIS FEATURE
WHICH WILL HELP TO MAINTAIN CLOUD COVER.

&&

.SHORT TERM /TONIGHT THROUGH MONDAY/...
SHORTWAVE TROUGH WILL SWING THROUGH TONIGHT. PRECIP IS NOT
EXPECTED...BUT AGAIN CLOUD COVER WILL BE MAINTAINED WITH THE UPPER
LEVEL SYSTEM.

MODELS ARE SHOWING SOME IMPROVEMENT SUNDAY...PARTICULARLY OVER THE
WEST AND FAR SOUTH. HOWEVER...MODEL SOUNDINGS FOR THE REST OF THE
REGION STILL WANT TO MAINTAIN A SATURATED LAYER AROUND 2500FT FOR
MOST OF THE DAY...WHICH DOES NOT PRESENT MUCH HOPE FOR SUNSHINE.
CLOUDS WILL BE TRICKY ON SUNDAY...TRYING TO DETERMINE HOW MUCH OF
THE STRAOCU DECK WILL BE ERODED.

SPLIT FLOW DEVELOPS ON MONDAY WITH A LARGE SYSTEM TO THE WEST AND
ANOTHER SYSTEM TO THE SOUTH-SOUTHEAST. IT APPEARS THAT THE AREA
WILL LIE IN BETWEEN LIMITING THE CHANCES FOR PRECIPITATION. WAA
WILL CONTINUE ON MONDAY AND LOW-LEVEL MOISTURE INCREASES ONCE
AGAIN. LOOKS LIKE A GOOD DEAL OF CLOUD COVER AGAIN MONDAY. A WEAK
AND UNORGANIZED SHORTWAVE TROUGH WILL SWING THROUGH
MONDAY...ALLOWING FOR THE POSSIBILITY OF SOME LIGHT PRECIP...MAINLY
OVER THE SOUTHERN RIDGES. THIS WILL NEED TO BE FINE TUNED AS THE
WARMER AIR ALOFT MAY OCCUR BEFORE SURFACE TEMPS RESPOND. TIMING OF
THE PRECIP WILL BE CRITICAL TO PROVIDING TIME FOR SURFACE TEMPS IN
THE SOUTHERN RIDGES TO RISE. FOR NOW WILL MENTION A CHANCE FOR
FREEZING RAIN IN THE SOUTHERN RIDGES...BUT CONFIDENCE IS LOW.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
STILL SEEING SOME MINOR DIFFERENCES IN MEDIUM RANGE MODEL
SOLUTIONS FOR MIDWEEK SYSTEM. THINK MUCH OF TUESDAY COULD BE DRY
OR JUST LIGHT SHOWERS AS AREA WILL BE WELL INTO THE WARM SECTOR. RAIN
WILL OVERSPREAD THE AREA TUESDAY NIGHT AHEAD OF OCCLUDED FRONT AND
CONTINUE THROUGH WEDNESDAY. COLDER AIR WILL MOVE IN LATER
WEDNESDAY NIGHT CHANGING ANY LINGERING SHOWERS TO SNOW SHOWERS.
COULD SEE A BRIEF UPTICK IN SNOW SHOWER COVERAGE EARLY THURSDAY
MORNING AS MAIN TROUGH SWINGS THROUGH. COLD AIR WILL BE IN PLACE
THURSDAY...BUT WIND DIRECTION NOT OPTIMAL FOR LAKE INFLUENCED SNOW
SHOWERS.

WARMER AIR WILL MOVE BACK IN THURSDAY NIGHT AND FRIDAY.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
LOW LEVEL MOISTURE WILL REMAIN TRAPPED UNDER A STRONG INVERSION
AOB 4KFT AS LOW LEVEL WINDS BECOME LIGHT....MAINTAINING HIGH MVFR
TO LOW VFR CONDITIONS OVER THE NEXT 24 HOURS. PRECIPITATION
CHANCES ARE MINIMAL GIVEN THE SHALLOW DEPTH OF THE SATURATED
LAYER AND ABSENCE OF ANY LIFT.

OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST THROUGH THE WEEKEND. NEXT STORM
SYSTEM WILL BEGIN TO IMPACT THE REGION ON TUESDAY AND RESULT IN
WIDESPREAD RAIN...CIG/VIS RESTRICTIONS...AND PERIODS OF LLWS
THROUGH WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$






000
FXUS61 KPBZ 200614
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
114 AM EST SAT DEC 20 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /THROUGH TODAY/...
OVERNIGHT PERIOD IN GOOD SHAPE. STRATOCU REMAINS TRAPPED UNDER
WEAK RIDGE. TEMPS HAVE BEEN ADJUSTED TO LATEST GUIDANCE.

WEAK RIDGE BREAKS DOWN LATER TODAY AS SHORTWAVE TROUGH WILL MOVE
THROUGH THE UPPER MIDWEST. WEAK CAA IS EXPECTED WITH THIS FEATURE
WHICH WILL HELP TO MAINTAIN CLOUD COVER.

&&

.SHORT TERM /TONIGHT THROUGH MONDAY/...
SHORTWAVE TROUGH WILL SWING THROUGH TONIGHT. PRECIP IS NOT
EXPECTED...BUT AGAIN CLOUD COVER WILL BE MAINTAINED WITH THE UPPER
LEVEL SYSTEM.

MODELS ARE SHOWING SOME IMPROVEMENT SUNDAY...PARTICULARLY OVER THE
WEST AND FAR SOUTH. HOWEVER...MODEL SOUNDINGS FOR THE REST OF THE
REGION STILL WANT TO MAINTAIN A SATURATED LAYER AROUND 2500FT FOR
MOST OF THE DAY...WHICH DOES NOT PRESENT MUCH HOPE FOR SUNSHINE.
CLOUDS WILL BE TRICKY ON SUNDAY...TRYING TO DETERMINE HOW MUCH OF
THE STRAOCU DECK WILL BE ERODED.

SPLIT FLOW DEVELOPS ON MONDAY WITH A LARGE SYSTEM TO THE WEST AND
ANOTHER SYSTEM TO THE SOUTH-SOUTHEAST. IT APPEARS THAT THE AREA
WILL LIE IN BETWEEN LIMITING THE CHANCES FOR PRECIPITATION. WAA
WILL CONTINUE ON MONDAY AND LOW-LEVEL MOISTURE INCREASES ONCE
AGAIN. LOOKS LIKE A GOOD DEAL OF CLOUD COVER AGAIN MONDAY. A WEAK
AND UNORGANIZED SHORTWAVE TROUGH WILL SWING THROUGH
MONDAY...ALLOWING FOR THE POSSIBILITY OF SOME LIGHT PRECIP...MAINLY
OVER THE SOUTHERN RIDGES. THIS WILL NEED TO BE FINE TUNED AS THE
WARMER AIR ALOFT MAY OCCUR BEFORE SURFACE TEMPS RESPOND. TIMING OF
THE PRECIP WILL BE CRITICAL TO PROVIDING TIME FOR SURFACE TEMPS IN
THE SOUTHERN RIDGES TO RISE. FOR NOW WILL MENTION A CHANCE FOR
FREEZING RAIN IN THE SOUTHERN RIDGES...BUT CONFIDENCE IS LOW.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
STILL SEEING SOME MINOR DIFFERENCES IN MEDIUM RANGE MODEL
SOLUTIONS FOR MIDWEEK SYSTEM. THINK MUCH OF TUESDAY COULD BE DRY
OR JUST LIGHT SHOWERS AS AREA WILL BE WELL INTO THE WARM SECTOR. RAIN
WILL OVERSPREAD THE AREA TUESDAY NIGHT AHEAD OF OCCLUDED FRONT AND
CONTINUE THROUGH WEDNESDAY. COLDER AIR WILL MOVE IN LATER
WEDNESDAY NIGHT CHANGING ANY LINGERING SHOWERS TO SNOW SHOWERS.
COULD SEE A BRIEF UPTICK IN SNOW SHOWER COVERAGE EARLY THURSDAY
MORNING AS MAIN TROUGH SWINGS THROUGH. COLD AIR WILL BE IN PLACE
THURSDAY...BUT WIND DIRECTION NOT OPTIMAL FOR LAKE INFLUENCED SNOW
SHOWERS.

WARMER AIR WILL MOVE BACK IN THURSDAY NIGHT AND FRIDAY.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
LOW LEVEL MOISTURE WILL REMAIN TRAPPED UNDER A STRONG INVERSION
AOB 4KFT AS LOW LEVEL WINDS BECOME LIGHT....MAINTAINING HIGH MVFR
TO LOW VFR CONDITIONS OVER THE NEXT 24 HOURS. PRECIPITATION
CHANCES ARE MINIMAL GIVEN THE SHALLOW DEPTH OF THE SATURATED
LAYER AND ABSENCE OF ANY LIFT.

OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST THROUGH THE WEEKEND. NEXT STORM
SYSTEM WILL BEGIN TO IMPACT THE REGION ON TUESDAY AND RESULT IN
WIDESPREAD RAIN...CIG/VIS RESTRICTIONS...AND PERIODS OF LLWS
THROUGH WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$






000
FXUS61 KPBZ 200614
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
114 AM EST SAT DEC 20 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /THROUGH TODAY/...
OVERNIGHT PERIOD IN GOOD SHAPE. STRATOCU REMAINS TRAPPED UNDER
WEAK RIDGE. TEMPS HAVE BEEN ADJUSTED TO LATEST GUIDANCE.

WEAK RIDGE BREAKS DOWN LATER TODAY AS SHORTWAVE TROUGH WILL MOVE
THROUGH THE UPPER MIDWEST. WEAK CAA IS EXPECTED WITH THIS FEATURE
WHICH WILL HELP TO MAINTAIN CLOUD COVER.

&&

.SHORT TERM /TONIGHT THROUGH MONDAY/...
SHORTWAVE TROUGH WILL SWING THROUGH TONIGHT. PRECIP IS NOT
EXPECTED...BUT AGAIN CLOUD COVER WILL BE MAINTAINED WITH THE UPPER
LEVEL SYSTEM.

MODELS ARE SHOWING SOME IMPROVEMENT SUNDAY...PARTICULARLY OVER THE
WEST AND FAR SOUTH. HOWEVER...MODEL SOUNDINGS FOR THE REST OF THE
REGION STILL WANT TO MAINTAIN A SATURATED LAYER AROUND 2500FT FOR
MOST OF THE DAY...WHICH DOES NOT PRESENT MUCH HOPE FOR SUNSHINE.
CLOUDS WILL BE TRICKY ON SUNDAY...TRYING TO DETERMINE HOW MUCH OF
THE STRAOCU DECK WILL BE ERODED.

SPLIT FLOW DEVELOPS ON MONDAY WITH A LARGE SYSTEM TO THE WEST AND
ANOTHER SYSTEM TO THE SOUTH-SOUTHEAST. IT APPEARS THAT THE AREA
WILL LIE IN BETWEEN LIMITING THE CHANCES FOR PRECIPITATION. WAA
WILL CONTINUE ON MONDAY AND LOW-LEVEL MOISTURE INCREASES ONCE
AGAIN. LOOKS LIKE A GOOD DEAL OF CLOUD COVER AGAIN MONDAY. A WEAK
AND UNORGANIZED SHORTWAVE TROUGH WILL SWING THROUGH
MONDAY...ALLOWING FOR THE POSSIBILITY OF SOME LIGHT PRECIP...MAINLY
OVER THE SOUTHERN RIDGES. THIS WILL NEED TO BE FINE TUNED AS THE
WARMER AIR ALOFT MAY OCCUR BEFORE SURFACE TEMPS RESPOND. TIMING OF
THE PRECIP WILL BE CRITICAL TO PROVIDING TIME FOR SURFACE TEMPS IN
THE SOUTHERN RIDGES TO RISE. FOR NOW WILL MENTION A CHANCE FOR
FREEZING RAIN IN THE SOUTHERN RIDGES...BUT CONFIDENCE IS LOW.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
STILL SEEING SOME MINOR DIFFERENCES IN MEDIUM RANGE MODEL
SOLUTIONS FOR MIDWEEK SYSTEM. THINK MUCH OF TUESDAY COULD BE DRY
OR JUST LIGHT SHOWERS AS AREA WILL BE WELL INTO THE WARM SECTOR. RAIN
WILL OVERSPREAD THE AREA TUESDAY NIGHT AHEAD OF OCCLUDED FRONT AND
CONTINUE THROUGH WEDNESDAY. COLDER AIR WILL MOVE IN LATER
WEDNESDAY NIGHT CHANGING ANY LINGERING SHOWERS TO SNOW SHOWERS.
COULD SEE A BRIEF UPTICK IN SNOW SHOWER COVERAGE EARLY THURSDAY
MORNING AS MAIN TROUGH SWINGS THROUGH. COLD AIR WILL BE IN PLACE
THURSDAY...BUT WIND DIRECTION NOT OPTIMAL FOR LAKE INFLUENCED SNOW
SHOWERS.

WARMER AIR WILL MOVE BACK IN THURSDAY NIGHT AND FRIDAY.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
LOW LEVEL MOISTURE WILL REMAIN TRAPPED UNDER A STRONG INVERSION
AOB 4KFT AS LOW LEVEL WINDS BECOME LIGHT....MAINTAINING HIGH MVFR
TO LOW VFR CONDITIONS OVER THE NEXT 24 HOURS. PRECIPITATION
CHANCES ARE MINIMAL GIVEN THE SHALLOW DEPTH OF THE SATURATED
LAYER AND ABSENCE OF ANY LIFT.

OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST THROUGH THE WEEKEND. NEXT STORM
SYSTEM WILL BEGIN TO IMPACT THE REGION ON TUESDAY AND RESULT IN
WIDESPREAD RAIN...CIG/VIS RESTRICTIONS...AND PERIODS OF LLWS
THROUGH WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$






000
FXUS61 KPBZ 200547 AAC
AFDPBZ

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PITTSBURGH PA
1247 AM EST SAT DEC 20 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /THROUGH TODAY/...
OVERNIGHT PERIOD IN GOOD SHAPE. STRATOCU REMAINS TRAPPED UNDER
WEAK RIDGE. TEMPS HAVE BEEN ADJUSTED TO LATEST GUIDANCE.

WEAK RIDGE BREAKS DOWN LATER TODAY AS SHORTWAVE TROUGH WILL MOVE
THROUGH THE UPPER MIDWEST. WEAK CAA IS EXPECTED WITH THIS FEATURE
WHICH WILL HELP TO MAINTAIN CLOUD COVER.

&&

.SHORT TERM /TONIGHT THROUGH MONDAY/...
SHORTWAVE TROUGH WILL SWING THROUGH TONIGHT. PRECIP IS NOT
EXPECTED...BUT AGAIN CLOUD COVER WILL BE MAINTAINED WITH THE UPPER
LEVEL SYSTEM.

MODELS ARE SHOWING SOME IMPROVEMENT SUNDAY...PARTICULARLY OVER THE
WEST AND FAR SOUTH. HOWEVER...MODEL SOUNDINGS FOR THE REST OF THE
REGION STILL WANT TO MAINTAIN A SATURATED LAYER AROUND 2500FT FOR
MOST OF THE DAY...WHICH DOES NOT PRESENT MUCH HOPE FOR SUNSHINE.
CLOUDS WILL BE TRICKY ON SUNDAY...TRYING TO DETERMINE HOW MUCH OF
THE STRAOCU DECK WILL BE ERODED.

SPLIT FLOW DEVELOPS ON MONDAY WITH A LARGE SYSTEM TO THE WEST AND
ANOTHER SYSTEM TO THE SOUTH-SOUTHEAST. IT APPEARS THAT THE AREA
WILL LIE IN BETWEEN LIMITING THE CHANCES FOR PRECIPITATION. WAA
WILL CONTINUE ON MONDAY AND LOW-LEVEL MOISTURE INCREASES ONCE
AGAIN. LOOKS LIKE A GOOD DEAL OF CLOUD COVER AGAIN MONDAY. A WEAK
AND UNORGANIZED SHORTWAVE TROUGH WILL SWING THROUGH
MONDAY...ALLOWING FOR THE POSSIBILITY OF SOME LIGHT PRECIP...MAINLY
OVER THE SOUTHERN RIDGES. THIS WILL NEED TO BE FINE TUNED AS THE
WARMER AIR ALOFT MAY OCCUR BEFORE SURFACE TEMPS RESPOND. TIMING OF
THE PRECIP WILL BE CRITICAL TO PROVIDING TIME FOR SURFACE TEMPS IN
THE SOUTHERN RIDGES TO RISE. FOR NOW WILL MENTION A CHANCE FOR
FREEZING RAIN IN THE SOUTHERN RIDGES...BUT CONFIDENCE IS LOW.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
STILL SEEING SOME MINOR DIFFERENCES IN MEDIUM RANGE MODEL
SOLUTIONS FOR MIDWEEK SYSTEM. THINK MUCH OF TUESDAY COULD BE DRY
OR JUST LIGHT SHOWERS AS AREA WILL BE WELL INTO THE WARM SECTOR. RAIN
WILL OVERSPREAD THE AREA TUESDAY NIGHT AHEAD OF OCCLUDED FRONT AND
CONTINUE THROUGH WEDNESDAY. COLDER AIR WILL MOVE IN LATER
WEDNESDAY NIGHT CHANGING ANY LINGERING SHOWERS TO SNOW SHOWERS.
COULD SEE A BRIEF UPTICK IN SNOW SHOWER COVERAGE EARLY THURSDAY
MORNING AS MAIN TROUGH SWINGS THROUGH. COLD AIR WILL BE IN PLACE
THURSDAY...BUT WIND DIRECTION NOT OPTIMAL FOR LAKE INFLUENCED SNOW
SHOWERS.

WARMER AIR WILL MOVE BACK IN THURSDAY NIGHT AND FRIDAY.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
PERVASIVE STRATUS COVERS ALL SITES THIS EVENING...WHILE BOUNDARY
LAYER MOISTURE HAS DROPPED OFF FROM EARLIER TODAY. GIVEN STRONG
INVERSIONS...STRATUS SEEMS LIKELY TO CONTINUE FOR THE NEXT DAY AT
LEAST...HOWEVER GIVEN A BIT WIDER DEWPOINT DEPRESSIONS...LIGHT
PRECIPITATION CHANCES SEEM VERY LOW. MVFR CONDITIONS SEEM LIKELY
TO CONTINUE. FRIES


OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY AND WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$







000
FXUS61 KPBZ 200547 AAC
AFDPBZ

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PITTSBURGH PA
1247 AM EST SAT DEC 20 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /THROUGH TODAY/...
OVERNIGHT PERIOD IN GOOD SHAPE. STRATOCU REMAINS TRAPPED UNDER
WEAK RIDGE. TEMPS HAVE BEEN ADJUSTED TO LATEST GUIDANCE.

WEAK RIDGE BREAKS DOWN LATER TODAY AS SHORTWAVE TROUGH WILL MOVE
THROUGH THE UPPER MIDWEST. WEAK CAA IS EXPECTED WITH THIS FEATURE
WHICH WILL HELP TO MAINTAIN CLOUD COVER.

&&

.SHORT TERM /TONIGHT THROUGH MONDAY/...
SHORTWAVE TROUGH WILL SWING THROUGH TONIGHT. PRECIP IS NOT
EXPECTED...BUT AGAIN CLOUD COVER WILL BE MAINTAINED WITH THE UPPER
LEVEL SYSTEM.

MODELS ARE SHOWING SOME IMPROVEMENT SUNDAY...PARTICULARLY OVER THE
WEST AND FAR SOUTH. HOWEVER...MODEL SOUNDINGS FOR THE REST OF THE
REGION STILL WANT TO MAINTAIN A SATURATED LAYER AROUND 2500FT FOR
MOST OF THE DAY...WHICH DOES NOT PRESENT MUCH HOPE FOR SUNSHINE.
CLOUDS WILL BE TRICKY ON SUNDAY...TRYING TO DETERMINE HOW MUCH OF
THE STRAOCU DECK WILL BE ERODED.

SPLIT FLOW DEVELOPS ON MONDAY WITH A LARGE SYSTEM TO THE WEST AND
ANOTHER SYSTEM TO THE SOUTH-SOUTHEAST. IT APPEARS THAT THE AREA
WILL LIE IN BETWEEN LIMITING THE CHANCES FOR PRECIPITATION. WAA
WILL CONTINUE ON MONDAY AND LOW-LEVEL MOISTURE INCREASES ONCE
AGAIN. LOOKS LIKE A GOOD DEAL OF CLOUD COVER AGAIN MONDAY. A WEAK
AND UNORGANIZED SHORTWAVE TROUGH WILL SWING THROUGH
MONDAY...ALLOWING FOR THE POSSIBILITY OF SOME LIGHT PRECIP...MAINLY
OVER THE SOUTHERN RIDGES. THIS WILL NEED TO BE FINE TUNED AS THE
WARMER AIR ALOFT MAY OCCUR BEFORE SURFACE TEMPS RESPOND. TIMING OF
THE PRECIP WILL BE CRITICAL TO PROVIDING TIME FOR SURFACE TEMPS IN
THE SOUTHERN RIDGES TO RISE. FOR NOW WILL MENTION A CHANCE FOR
FREEZING RAIN IN THE SOUTHERN RIDGES...BUT CONFIDENCE IS LOW.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
STILL SEEING SOME MINOR DIFFERENCES IN MEDIUM RANGE MODEL
SOLUTIONS FOR MIDWEEK SYSTEM. THINK MUCH OF TUESDAY COULD BE DRY
OR JUST LIGHT SHOWERS AS AREA WILL BE WELL INTO THE WARM SECTOR. RAIN
WILL OVERSPREAD THE AREA TUESDAY NIGHT AHEAD OF OCCLUDED FRONT AND
CONTINUE THROUGH WEDNESDAY. COLDER AIR WILL MOVE IN LATER
WEDNESDAY NIGHT CHANGING ANY LINGERING SHOWERS TO SNOW SHOWERS.
COULD SEE A BRIEF UPTICK IN SNOW SHOWER COVERAGE EARLY THURSDAY
MORNING AS MAIN TROUGH SWINGS THROUGH. COLD AIR WILL BE IN PLACE
THURSDAY...BUT WIND DIRECTION NOT OPTIMAL FOR LAKE INFLUENCED SNOW
SHOWERS.

WARMER AIR WILL MOVE BACK IN THURSDAY NIGHT AND FRIDAY.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
PERVASIVE STRATUS COVERS ALL SITES THIS EVENING...WHILE BOUNDARY
LAYER MOISTURE HAS DROPPED OFF FROM EARLIER TODAY. GIVEN STRONG
INVERSIONS...STRATUS SEEMS LIKELY TO CONTINUE FOR THE NEXT DAY AT
LEAST...HOWEVER GIVEN A BIT WIDER DEWPOINT DEPRESSIONS...LIGHT
PRECIPITATION CHANCES SEEM VERY LOW. MVFR CONDITIONS SEEM LIKELY
TO CONTINUE. FRIES


OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY AND WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$







000
FXUS61 KPBZ 200547 AAC
AFDPBZ

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PITTSBURGH PA
1247 AM EST SAT DEC 20 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /THROUGH TODAY/...
OVERNIGHT PERIOD IN GOOD SHAPE. STRATOCU REMAINS TRAPPED UNDER
WEAK RIDGE. TEMPS HAVE BEEN ADJUSTED TO LATEST GUIDANCE.

WEAK RIDGE BREAKS DOWN LATER TODAY AS SHORTWAVE TROUGH WILL MOVE
THROUGH THE UPPER MIDWEST. WEAK CAA IS EXPECTED WITH THIS FEATURE
WHICH WILL HELP TO MAINTAIN CLOUD COVER.

&&

.SHORT TERM /TONIGHT THROUGH MONDAY/...
SHORTWAVE TROUGH WILL SWING THROUGH TONIGHT. PRECIP IS NOT
EXPECTED...BUT AGAIN CLOUD COVER WILL BE MAINTAINED WITH THE UPPER
LEVEL SYSTEM.

MODELS ARE SHOWING SOME IMPROVEMENT SUNDAY...PARTICULARLY OVER THE
WEST AND FAR SOUTH. HOWEVER...MODEL SOUNDINGS FOR THE REST OF THE
REGION STILL WANT TO MAINTAIN A SATURATED LAYER AROUND 2500FT FOR
MOST OF THE DAY...WHICH DOES NOT PRESENT MUCH HOPE FOR SUNSHINE.
CLOUDS WILL BE TRICKY ON SUNDAY...TRYING TO DETERMINE HOW MUCH OF
THE STRAOCU DECK WILL BE ERODED.

SPLIT FLOW DEVELOPS ON MONDAY WITH A LARGE SYSTEM TO THE WEST AND
ANOTHER SYSTEM TO THE SOUTH-SOUTHEAST. IT APPEARS THAT THE AREA
WILL LIE IN BETWEEN LIMITING THE CHANCES FOR PRECIPITATION. WAA
WILL CONTINUE ON MONDAY AND LOW-LEVEL MOISTURE INCREASES ONCE
AGAIN. LOOKS LIKE A GOOD DEAL OF CLOUD COVER AGAIN MONDAY. A WEAK
AND UNORGANIZED SHORTWAVE TROUGH WILL SWING THROUGH
MONDAY...ALLOWING FOR THE POSSIBILITY OF SOME LIGHT PRECIP...MAINLY
OVER THE SOUTHERN RIDGES. THIS WILL NEED TO BE FINE TUNED AS THE
WARMER AIR ALOFT MAY OCCUR BEFORE SURFACE TEMPS RESPOND. TIMING OF
THE PRECIP WILL BE CRITICAL TO PROVIDING TIME FOR SURFACE TEMPS IN
THE SOUTHERN RIDGES TO RISE. FOR NOW WILL MENTION A CHANCE FOR
FREEZING RAIN IN THE SOUTHERN RIDGES...BUT CONFIDENCE IS LOW.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
STILL SEEING SOME MINOR DIFFERENCES IN MEDIUM RANGE MODEL
SOLUTIONS FOR MIDWEEK SYSTEM. THINK MUCH OF TUESDAY COULD BE DRY
OR JUST LIGHT SHOWERS AS AREA WILL BE WELL INTO THE WARM SECTOR. RAIN
WILL OVERSPREAD THE AREA TUESDAY NIGHT AHEAD OF OCCLUDED FRONT AND
CONTINUE THROUGH WEDNESDAY. COLDER AIR WILL MOVE IN LATER
WEDNESDAY NIGHT CHANGING ANY LINGERING SHOWERS TO SNOW SHOWERS.
COULD SEE A BRIEF UPTICK IN SNOW SHOWER COVERAGE EARLY THURSDAY
MORNING AS MAIN TROUGH SWINGS THROUGH. COLD AIR WILL BE IN PLACE
THURSDAY...BUT WIND DIRECTION NOT OPTIMAL FOR LAKE INFLUENCED SNOW
SHOWERS.

WARMER AIR WILL MOVE BACK IN THURSDAY NIGHT AND FRIDAY.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
PERVASIVE STRATUS COVERS ALL SITES THIS EVENING...WHILE BOUNDARY
LAYER MOISTURE HAS DROPPED OFF FROM EARLIER TODAY. GIVEN STRONG
INVERSIONS...STRATUS SEEMS LIKELY TO CONTINUE FOR THE NEXT DAY AT
LEAST...HOWEVER GIVEN A BIT WIDER DEWPOINT DEPRESSIONS...LIGHT
PRECIPITATION CHANCES SEEM VERY LOW. MVFR CONDITIONS SEEM LIKELY
TO CONTINUE. FRIES


OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY AND WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$







000
FXUS61 KPBZ 200547 AAC
AFDPBZ

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PITTSBURGH PA
1247 AM EST SAT DEC 20 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /THROUGH TODAY/...
OVERNIGHT PERIOD IN GOOD SHAPE. STRATOCU REMAINS TRAPPED UNDER
WEAK RIDGE. TEMPS HAVE BEEN ADJUSTED TO LATEST GUIDANCE.

WEAK RIDGE BREAKS DOWN LATER TODAY AS SHORTWAVE TROUGH WILL MOVE
THROUGH THE UPPER MIDWEST. WEAK CAA IS EXPECTED WITH THIS FEATURE
WHICH WILL HELP TO MAINTAIN CLOUD COVER.

&&

.SHORT TERM /TONIGHT THROUGH MONDAY/...
SHORTWAVE TROUGH WILL SWING THROUGH TONIGHT. PRECIP IS NOT
EXPECTED...BUT AGAIN CLOUD COVER WILL BE MAINTAINED WITH THE UPPER
LEVEL SYSTEM.

MODELS ARE SHOWING SOME IMPROVEMENT SUNDAY...PARTICULARLY OVER THE
WEST AND FAR SOUTH. HOWEVER...MODEL SOUNDINGS FOR THE REST OF THE
REGION STILL WANT TO MAINTAIN A SATURATED LAYER AROUND 2500FT FOR
MOST OF THE DAY...WHICH DOES NOT PRESENT MUCH HOPE FOR SUNSHINE.
CLOUDS WILL BE TRICKY ON SUNDAY...TRYING TO DETERMINE HOW MUCH OF
THE STRAOCU DECK WILL BE ERODED.

SPLIT FLOW DEVELOPS ON MONDAY WITH A LARGE SYSTEM TO THE WEST AND
ANOTHER SYSTEM TO THE SOUTH-SOUTHEAST. IT APPEARS THAT THE AREA
WILL LIE IN BETWEEN LIMITING THE CHANCES FOR PRECIPITATION. WAA
WILL CONTINUE ON MONDAY AND LOW-LEVEL MOISTURE INCREASES ONCE
AGAIN. LOOKS LIKE A GOOD DEAL OF CLOUD COVER AGAIN MONDAY. A WEAK
AND UNORGANIZED SHORTWAVE TROUGH WILL SWING THROUGH
MONDAY...ALLOWING FOR THE POSSIBILITY OF SOME LIGHT PRECIP...MAINLY
OVER THE SOUTHERN RIDGES. THIS WILL NEED TO BE FINE TUNED AS THE
WARMER AIR ALOFT MAY OCCUR BEFORE SURFACE TEMPS RESPOND. TIMING OF
THE PRECIP WILL BE CRITICAL TO PROVIDING TIME FOR SURFACE TEMPS IN
THE SOUTHERN RIDGES TO RISE. FOR NOW WILL MENTION A CHANCE FOR
FREEZING RAIN IN THE SOUTHERN RIDGES...BUT CONFIDENCE IS LOW.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
STILL SEEING SOME MINOR DIFFERENCES IN MEDIUM RANGE MODEL
SOLUTIONS FOR MIDWEEK SYSTEM. THINK MUCH OF TUESDAY COULD BE DRY
OR JUST LIGHT SHOWERS AS AREA WILL BE WELL INTO THE WARM SECTOR. RAIN
WILL OVERSPREAD THE AREA TUESDAY NIGHT AHEAD OF OCCLUDED FRONT AND
CONTINUE THROUGH WEDNESDAY. COLDER AIR WILL MOVE IN LATER
WEDNESDAY NIGHT CHANGING ANY LINGERING SHOWERS TO SNOW SHOWERS.
COULD SEE A BRIEF UPTICK IN SNOW SHOWER COVERAGE EARLY THURSDAY
MORNING AS MAIN TROUGH SWINGS THROUGH. COLD AIR WILL BE IN PLACE
THURSDAY...BUT WIND DIRECTION NOT OPTIMAL FOR LAKE INFLUENCED SNOW
SHOWERS.

WARMER AIR WILL MOVE BACK IN THURSDAY NIGHT AND FRIDAY.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
PERVASIVE STRATUS COVERS ALL SITES THIS EVENING...WHILE BOUNDARY
LAYER MOISTURE HAS DROPPED OFF FROM EARLIER TODAY. GIVEN STRONG
INVERSIONS...STRATUS SEEMS LIKELY TO CONTINUE FOR THE NEXT DAY AT
LEAST...HOWEVER GIVEN A BIT WIDER DEWPOINT DEPRESSIONS...LIGHT
PRECIPITATION CHANCES SEEM VERY LOW. MVFR CONDITIONS SEEM LIKELY
TO CONTINUE. FRIES


OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY AND WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$







000
FXUS61 KCTP 200455
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1155 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER THE WESTERN GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND...BRINGING DRY WEATHER WITH
LIGHTER WIND. A DEEP UPPER TROUGH AND ASSOCIATED SFC LOW WILL LIFT
NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE OF NEXT WEEK
LIKELY BRINGING US RAIN AND WIND FOR CHRISTMAS EVE...THEN BLUSTERY
AND COLDER CONDITIONS FOR CHRISTMAS DAY WITH SCATTERED SNOW
SHOWERS.

&&

.NEAR TERM /UNTIL 8 AM SATURDAY MORNING/...
930 PM UPDATE...
CLOUDS AND TEMPS BEHAVING. NO NEED FOR ANYTHING OTHER THAN TINY
TWEAKS.

7 PM UPDATE...
BIG BREAKS IN CLOUDS LOCALLY. NRLY FLOW IS SHOVING THE CLOUDS DOWN
INTO THE POCONOS AND TRYING TO GET THEM INTO LEB/LANC COS. AT THIS
POINT...WILL CONTINUE TO COUNT ON THE DOWNSLOPE TO KEEP IT FROM
GOING TOTALLY OVC...BUT SOME INCREASE IN CLOUDS OVER THE NEXT FEW
HRS IN THE SE IS PROBABLY A GOOD CALL. OTHERWISE...THE SUBSIDENCE
IN BETWEEN THE NERN AND SERN PARTS OF THE STATE MAY CONTINUE TO
OPEN UP BIGGER BREAKS. WILL HAVE TO TWEAK NWRN MIN TEMPS AS THEY
ARE EXTREMELY CLOSE TO GOING MINS ATTM. ELSEWHERE...DEWPOINTS AND
ONLY SLOW DECREASE IN COVG LOOK LIKE THE MINS ARE OKAY FOR NOW.

PREV...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK TRAPPED BELOW A
MODERATELY STRONG SUBSIDENCE INVERSION /BASED AT AROUND 2-3KFT
AGL/ WILL PERSIST ACROSS MUCH OF NORTHERN AND WESTERN PENNSYLVANIA
LATE TODAY INTO SATURDAY...WHILE PARTIAL CLEARING OCCURS ACROSS
THE LOWER SUSQ VALLEY AND SURROUNDING AREAS.

TEMPS WILL REMAIN STEADY THROUGH LATE THIS AFTERNOON UNDER THE
10-15 KT NWRLY FLOW. READINGS WILL VARY FROM THE MID TO UPPER 20S
ACROSS THE NORTHERN AND WESTERN MOUNTAINS...TO THE LOWER 40S IN
THE SOUTHEAST.

A WEAK SFC RIDGE WILL MOVE TO NEAR THE PENN/OHIO BORDER BY 12Z
SATURDAY...BUT THE WEAK WESTERLY ISENTROPIC LIFT ALONG THE 285K
THETA SFC...AND SOME SHALLOW MOISTURE BEING ADVECTED SWD INTO THE
NRN MTNS OF PENN FROM LAKE ONTARIO...WILL MAINTAIN MOSTLY CLOUDY
TO CLOUDY SKIES. LITTLE MORE THAN A FEW FLURRIES OR SPOTTY -FZDZ
WILL FALL FROM THIS THIN CLOUD LAYER ACROSS THE HIGHER TERRAIN OF
THE LAURELS AND INVOF KBFD.

AFTER A PTLY CLOUDY LATE AFTERNOON AND EVENING IN THE SE PART OF
THE CWA...A BKN LAYER OF STRATO CU IS EXPECTED TO DRIFT SE /OR
FORM/ ACROSS THE REGION OVERNIGHT.

DUE TO THE NW-SE GRADIENT OF DECREASING CLOUDS...LOW TEMPS AT
DAYBREAK SAT WILL BE IN A RATHER TIGHT RANGE...FROM THE UPPER
TEENS TO LOWER 20S ACROSS THE MOUNTAINS...TO THE LOWER 20S IN THE
SE

&&

.SHORT TERM /8 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
A RIDGE OF HIGH PRESSURE...LIGHTER WIND...AND ASSOC DRIER AIR
MASS WILL BUILD EAST ACROSS THE STATE SATURDAY...PROVIDING THE
AREA WITH FAIR WEATHER.

HIGH RES MODEL DATA CONTINUES TO PAINT A MOSTLY CLOUDY PICTURE FOR
MUCH OF THE REGION SATURDAY INTO SATURDAY NIGHT...THOUGH PERIODS
OF SUNSHINE ARE LIKELY THROUGHOUT THE CENTRAL RIDGE AND VALLEY
REGION...AND SUSQUEHANNA RIVER VALLEY.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS OVER THE LOWER/THIN STRATO CU
CLOUD DECK PRESENT ACROSS THE REGION SATURDAY. ALL 12Z OPERATIONAL
MODEL DATA CONTINUES TO SUPPORT A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS NEAR 30 ACROSS THE MTNS...AND MID TO UPPER 30S IN
THE SE.

MOSTLY CLOUDY SKIES WITH LIGHT WIND SAT NIGHT WILL YIELD LOWS IN
THE LOWER 20S ACROSS THE MTNS...AND GENERALLY THE MID 20S
ELSEWHERE.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGH PRES WILL PROVIDE TRANQUIL WEATHER ON SUNDAY...WITH PARTLY TO
MOSTLY SUNNY SKIES AND SEASONABLE TEMPS. AFTER THAT...THE WEATHER
WILL BECOME INCREASINGLY UNSETTLED AS NEXT WEEK PROGRESSES.

CLOUDS WILL INCR SUNDAY NIGHT INTO MONDAY...AS HIGH PRES LOSES
ITS GRIP AND A WEAK AREA OF LOW PRES ORGANIZES OVER THE SERN UNITED
STATES. LIGHT PRECIP WILL WORK NWD INTO PENNSYLVANIA LATE MONDAY
INTO MONDAY NIGHT AND CONTINUE INTO TUES. INITIALLY...CONDS WILL
BE COLD ENOUGH FOR THE POSSIBILITY OF SOME WINTRY PRECIP.
HOWEVER...WARMER AIR WILL MAKE ITS WAY NWD LATER MONDAY NIGHT INTO
TUES AND GRADUALLY CHANGE ANY LINGERING PRECIP OVER TO PLAIN RAIN.

A MORE SIGNIFICANT STORM SYSTEM WILL GET ORGANIZED OVER THE
MISSISSIPPI VALLEY TUES NIGHT BEFORE PUSHING NWD INTO THE GREAT
LAKES ON WED. THIS SYSTEM WILL DRAW EVEN MILDER AIR NWD INTO THE
REGION...AND PROVIDE A RAINY AND BREEZY CHRISTMAS EVE DAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS FROM WEST TO EAST ACROSS PA IS POSSIBLE LATE WED/WED
NIGHT. SCT SNOW SHOWERS WILL CONTINUE INTO THURS ACROSS MAINLY
NRN AND WRN PA.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
OPERATIONAL MODELS AND THE GEFS SHOWING 850HPA TEMPS ALREADY
BEGINNING TO RISE NEXT FRI.

&&

.AVIATION /04Z SATURDAY THROUGH WEDNESDAY/...
NORTHWESTERLY SFC FLOW THAT HAS CAUSED OROGRAPHIC FORCING OF A
SHALLOW MOIST LAYER WILL CONTINUE TO PRODUCE PLENTY OF CLOUDS
ACROSS THE NW AND THE LAURELS WITH MAINLY MVFR BKN-OVC CIGS
THROUGH TONIGHT. KJST AND KBFD WILL TREND IFR THROUGH 12Z...AND
CIGS WILL SLOWLY INCREASE AS THE LOW LEVELS DRY OUT BY MID TO LATE
TOMORROW MORNING. IN CONTRAST...THE SE PENN AIRFIELDS SUCH AS
KMDT...KTHV AND KLNS WILL SEE MAINLY VFR.

NORTHWEST WINDS OF 10-15 KTS WITH HIGHER GUSTS WILL DECREASE TO 8
KTS OR LESS LATER TONIGHT AND SATURDAY.

HIGH PRESSURE BUILDS EAST ACROSS PENN SATURDAY...WITH BKN-OVC CIGS
VARYING BETWEEN MVFR OVER THE HIGHER TERRAIN OF THE NORTH AND
WEST...TO SCT-BKN VFR IN THE VALLEYS.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...EVANEGO
AVIATION...LAMBERT/CERU



000
FXUS61 KPHI 200240
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
940 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE JUST NORTH OF LAKE HURON WILL GRADUALLY MOVE
EASTWARD INTO NORTHERN NEW ENGLAND THRU MONDAY. A WAVE OF LOW
PRESSURE WILL FORM ALONG THE MID-ATLANTIC COASTLINE ON MONDAY AND
MOVE NORTHEASTWARD JUST OFFSHORE ON TUESDAY. A STRONG AREA OF
LOW PRESSURE WILL THEN FORM OVER THE MISSISSIPPI VALLEY AND MOVE
THRU THE GREAT LAKES REGION DURING THE MIDDLE OF THE
WEEK, BRINGING A STRONG COLD FRONT THRU THE REGION BY THURSDAY.
HIGH PRESSURE IS PROJECTED TO BUILD IN ON FRIDAY.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
LOW CLOUDS STILL WORKING THEIR WAY SOUTHWARD DEEPER INTO OUR CWA.
IT DOES FEEL LIKE WE ARE STUCK IN THE STRATOCUMULUS VERSION OF
GROUND HOG DAY. OVERNIGHT THERE IS A LOW LEVEL VORT MAX THAT IS
KEEPING THE LOW CLOUDS PERPETUATING AND JUST ENOUGH OF AN
INVERSION TO GIVE THEM A COMFORT LEVEL. IT LOOKS TO TAKE MOST OF
THE OVERNIGHT FOR THIS TO FEATURE TO CLEAR. LATER AT NIGHT SOME OF
THE CIRRUS FROM THE ONCE FORMIDABLE LOOKING SOUTHERN STREAM SYSTEM
WILL ALSO REACH OUR CWA.

OUR ADJUSTMENT WAS TO INCREASE CLOUD COVERAGE, ESP NORTH AND BUMP
UP MIN TEMPS THERE. IN THE SOUTHERN HALF OF OUR CWA, THE SHORT
WAVE TRAJ BYPASSES IT, SO WE WENT WITH A PTLY CLDY NIGHT. WINDS
ARE LIGHT ENOUGH THAT WE KEPT RADIATING MINS IN THE NJ PINE
BARRENS AND INTERIOR DELMARVA. THERE WILL BE SOME FROST SCRAPING
COME SATURDAY MORNING IN THOSE AREAS.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/...
FOR SATURDAY...HIGH PRES CENTERED OVER CANADA SHIFTS EWD FROM
ONTARIO INTO QUEBEC. A RIDGE AXIS IS FCST TO EXTEND SWD THROUGH THE
MID-ATLANTIC REGION RESULTING IN ONLY LIGHT NLY WINDS. SOME LOW-LVL
MOISTURE SHOULD REMAIN TRAPPED BELOW THE LARGE-SCALE SUBSIDENCE
INVERSION BUT HARD TO SAY HOW EXTENSIVE ANY LOW CLOUDS MAY BE. THE
12-KM NAM SHOWS A THIN LOW CLOUD LAYER DEVELOPING DURG THE DAY BUT
HIGHER-RES ARW/NMM AND THE GFS DO NOT. THERE WILL BE SOME HIGHER
CLOUDS ALSO ASSOCD WITH THE SHRTWV NOW MOVING ENEWD OUT OF THE SRN
PLAINS...HWVR POPS REMAIN NEAR ZERO.

&&

.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
HIGHLIGHTS...

* SLIGHT CHANCE OF SNOW SHOWERS SUNDAY MORNING MAINLY NORTH.
* SNOW POSSIBLE NORTHWEST OF THE I-95 CORRIDOR LATE MONDAY
  THRU EARLY TUESDAY.
* POTENTIAL FOR HEAVY RAIN INCREASING ON CHRISTMAS EVE DAY.

OVERVIEW...

MID-LEVEL BLOCKING PATTERN OVER NOAM BEGINS TO DISLODGE IN RESPONSE
JET ENERGY MOVING INTO THE PACIFIC NORTHWEST THIS WEEKEND...CARVING
OUT A DEEP TROUGH OVER THE MS VALLEY EARLY EARLY NEXT WEEK...WHICH
LEADS TO INCLEMENT WEATHER IN THE TUESDAY THRU WEDNESDAY TIME FRAME.

DETAILS...

SUNDAY...
SHORTWAVE LIFTING THROUGH THE REGION EARLY IN THE DAY MAY GENERATE
ENOUGH LIFT ALONG WITH MARGINAL MOISTURE IN THE COLUMN TO PRODUCE
SOME LIGHT SNOW SHOWERS...MAINLY DURING THE PRE-DAWN HOURS. LITTLE
IF ANY ACCUMULATION EXPECTED AS MOISTURE IS VERY LIMITED. RIDGING
THEN BUILDS IN SO FAIR WEATHER IS EXPECTED THE REMAINDER OF THE DAY.

MONDAY AND TUESDAY...
HIGH PRESSURE ANCHORS ALONG THE LEE OF THE APPALACHIANS. A SOUTHERN
STREAM SHORTWAVE WILL INDUCE LOW-PRESSURE OF THE MID-ATLANTIC COAST.
MODELS BRING QPF NORTHWARD INTO THE AREA ON MONDAY NIGHT INTO EARLY
TUESDAY. THERMAL PROFILES ARE COLD ENOUGH FOR SNOW TO THE NORTHWEST
OF THE I-95 CORRIDOR...BUT THE BEST LIFT IS FOCUSED JUST SOUTHEAST
OF THIS AREA...AND THE SYSTEM COULD TRACK FURTHER TO THE SOUTH PER
12Z UKMET MODEL. STILL A LOT OF UNCERTAINTY WITH ULTIMATE TRACK.

WEDNESDAY...
A MID-LEVEL RIDGE WILL MOVE THROUGH THE REGION TUESDAY NIGHT INTO
EARLY WEDNESDAY LEADING TO A BRIEF RESPITE BETWEEN WEATHER SYSTEMS.
THEN A MID-LEVEL TROUGH IS PROJECTED TO BECOME NEGATIVELY TILTED
OVER THE OHIO VALLEY ON WED...LEADING TO A MERIDIONAL FLOW ALONG
THE EAST COAST...WITH THE ENTIRE COLUMN EXPECTED TO BE WELL ABOVE
FREEZING ACROSS THE CWA FAVORING A RAIN EVENT. THERE ARE SEVERAL
INGREDIENTS COMING TOGETHER FOR HEAVY RAIN. IN PARTICULAR...DEEP
GULF MOISTURE...LOW-LEVEL ISENTROPIC LIFT...MID-LEVEL PVA...AND
THE RIGHT-REAR QUADRANT OF A 140 KNOT UPPER-LEVEL JET JUST NORTH.
THE SYSTEM SHOULD BE FAIRLY PROGRESSIVE BUT WILL HAVE TO MONITOR
POTENTIAL FOR FLOODING.

THU AND FRI...
LOW-PRESSURE MOVES NORTHWARD INTO QUEBEC AND HIGH-PRESSURE BEGINS
TO BUILD IN. TEMPERATURES WILL RETURN TO SEASONABLE LEVELS AND
THERE COULD BE SNOW SHOWERS IN THE BLUSTERY NORTHWEST FLOW.

&&

.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

THE 00Z TAFS TAKE CIGS DOWN TO MVFR LEVELS TONIGHT FROM THE KPHL
AREA AIRPORTS NORTHWESTWARD WITH IMPROVEMENT ON SATURDAY. ITS BEEN
TOUGH TO SHAKE THIS STRATOCU LEVEL CLOUDINESS PATTERN.

FOR TONIGHT. LOW CLOUDS ADVANCING IN FROM THE HIGHER TERRAIN
AIRPORTS ARE STILL HEADING INTO THE TERMINALS. WE BRING MVFR CIG
POTENTIAL FROM THE GET GO AT KABE AND KRDG (HIER CONFIDENCE
OVERNIGHT) AND BRING IT DOWN TO THE KPHL METRO AIRPORTS AFTER 05Z.
WE LEAVE KACY AND KMIV VFR. WINDS WILL BE LIGHT FROM THE
NORTHWEST. NO VSBY RESTRICTIONS EXPECTED.

ON SATURDAY, PREDICTING THE MVFR CIG TO BECOME SCATTERED DURING
THE MORNING FROM THE KPHL METRO AIRPORTS NWWD WITH A CIRRUS CIG
ABOVE. KACY AND KMIV NOT EXPECTING A MVFR CIG. IT WILL BE A WEAK
PRESSURE PATTERN AND WINDS WILL BE LIGHT. A NORTHERLY DIRECTION
IS FAVORED, BUT SPEEDS ARE EXPECTED TO REMAIN BELOW 10 KNOTS,
PROBABLY PREDOMINATELY LESS THAN 6 KNOTS AT SOME OF THE MORE
RURAL AIRPORTS AND TERMINALS.

OUTLOOK...
SATURDAY NIGHT AND SUNDAY...VFR CONDITIONS EXPECTED.
MONDAY AND TUESDAY...IFR POSSIBLE IN SHRA AND SHSN.
WEDNESDAY...IFR POSSIBLE IN RAIN AND FOG.

&&

.MARINE...
SUB-SCA CONDS ARE EXPECTED FOR THE NEXT 24 HOURS AT LEAST. SMWHT
GUST NW WINDS THIS EVENING WILL GRADUALLY DIMINISH TONIGHT THROUGH
SATURDAY AS A RIDGE OF HIGH PRES MOVES OVERHEAD. SEAS ARE
CURRENTLY RUNNING 2 TO 3 FT BUT THEY SHOULD GRADUALLY DIMINISH
ALSO.

OUTLOOK...
SUNDAY AND MONDAY...SUB-SCA CONDITIONS EXPECTED.
TUESDAY...SCA MAY BE NEEDED FOR BUILDING SEAS.
WEDNESDAY...GALE WARNING MAY BE NEEDED.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANCK
NEAR TERM...GIGI
SHORT TERM...AMC
LONG TERM...FRANCK
AVIATION...FRANCK/GIGI
MARINE...AMC/FRANCK







000
FXUS61 KPHI 200240
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
940 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE JUST NORTH OF LAKE HURON WILL GRADUALLY MOVE
EASTWARD INTO NORTHERN NEW ENGLAND THRU MONDAY. A WAVE OF LOW
PRESSURE WILL FORM ALONG THE MID-ATLANTIC COASTLINE ON MONDAY AND
MOVE NORTHEASTWARD JUST OFFSHORE ON TUESDAY. A STRONG AREA OF
LOW PRESSURE WILL THEN FORM OVER THE MISSISSIPPI VALLEY AND MOVE
THRU THE GREAT LAKES REGION DURING THE MIDDLE OF THE
WEEK, BRINGING A STRONG COLD FRONT THRU THE REGION BY THURSDAY.
HIGH PRESSURE IS PROJECTED TO BUILD IN ON FRIDAY.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
LOW CLOUDS STILL WORKING THEIR WAY SOUTHWARD DEEPER INTO OUR CWA.
IT DOES FEEL LIKE WE ARE STUCK IN THE STRATOCUMULUS VERSION OF
GROUND HOG DAY. OVERNIGHT THERE IS A LOW LEVEL VORT MAX THAT IS
KEEPING THE LOW CLOUDS PERPETUATING AND JUST ENOUGH OF AN
INVERSION TO GIVE THEM A COMFORT LEVEL. IT LOOKS TO TAKE MOST OF
THE OVERNIGHT FOR THIS TO FEATURE TO CLEAR. LATER AT NIGHT SOME OF
THE CIRRUS FROM THE ONCE FORMIDABLE LOOKING SOUTHERN STREAM SYSTEM
WILL ALSO REACH OUR CWA.

OUR ADJUSTMENT WAS TO INCREASE CLOUD COVERAGE, ESP NORTH AND BUMP
UP MIN TEMPS THERE. IN THE SOUTHERN HALF OF OUR CWA, THE SHORT
WAVE TRAJ BYPASSES IT, SO WE WENT WITH A PTLY CLDY NIGHT. WINDS
ARE LIGHT ENOUGH THAT WE KEPT RADIATING MINS IN THE NJ PINE
BARRENS AND INTERIOR DELMARVA. THERE WILL BE SOME FROST SCRAPING
COME SATURDAY MORNING IN THOSE AREAS.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/...
FOR SATURDAY...HIGH PRES CENTERED OVER CANADA SHIFTS EWD FROM
ONTARIO INTO QUEBEC. A RIDGE AXIS IS FCST TO EXTEND SWD THROUGH THE
MID-ATLANTIC REGION RESULTING IN ONLY LIGHT NLY WINDS. SOME LOW-LVL
MOISTURE SHOULD REMAIN TRAPPED BELOW THE LARGE-SCALE SUBSIDENCE
INVERSION BUT HARD TO SAY HOW EXTENSIVE ANY LOW CLOUDS MAY BE. THE
12-KM NAM SHOWS A THIN LOW CLOUD LAYER DEVELOPING DURG THE DAY BUT
HIGHER-RES ARW/NMM AND THE GFS DO NOT. THERE WILL BE SOME HIGHER
CLOUDS ALSO ASSOCD WITH THE SHRTWV NOW MOVING ENEWD OUT OF THE SRN
PLAINS...HWVR POPS REMAIN NEAR ZERO.

&&

.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
HIGHLIGHTS...

* SLIGHT CHANCE OF SNOW SHOWERS SUNDAY MORNING MAINLY NORTH.
* SNOW POSSIBLE NORTHWEST OF THE I-95 CORRIDOR LATE MONDAY
  THRU EARLY TUESDAY.
* POTENTIAL FOR HEAVY RAIN INCREASING ON CHRISTMAS EVE DAY.

OVERVIEW...

MID-LEVEL BLOCKING PATTERN OVER NOAM BEGINS TO DISLODGE IN RESPONSE
JET ENERGY MOVING INTO THE PACIFIC NORTHWEST THIS WEEKEND...CARVING
OUT A DEEP TROUGH OVER THE MS VALLEY EARLY EARLY NEXT WEEK...WHICH
LEADS TO INCLEMENT WEATHER IN THE TUESDAY THRU WEDNESDAY TIME FRAME.

DETAILS...

SUNDAY...
SHORTWAVE LIFTING THROUGH THE REGION EARLY IN THE DAY MAY GENERATE
ENOUGH LIFT ALONG WITH MARGINAL MOISTURE IN THE COLUMN TO PRODUCE
SOME LIGHT SNOW SHOWERS...MAINLY DURING THE PRE-DAWN HOURS. LITTLE
IF ANY ACCUMULATION EXPECTED AS MOISTURE IS VERY LIMITED. RIDGING
THEN BUILDS IN SO FAIR WEATHER IS EXPECTED THE REMAINDER OF THE DAY.

MONDAY AND TUESDAY...
HIGH PRESSURE ANCHORS ALONG THE LEE OF THE APPALACHIANS. A SOUTHERN
STREAM SHORTWAVE WILL INDUCE LOW-PRESSURE OF THE MID-ATLANTIC COAST.
MODELS BRING QPF NORTHWARD INTO THE AREA ON MONDAY NIGHT INTO EARLY
TUESDAY. THERMAL PROFILES ARE COLD ENOUGH FOR SNOW TO THE NORTHWEST
OF THE I-95 CORRIDOR...BUT THE BEST LIFT IS FOCUSED JUST SOUTHEAST
OF THIS AREA...AND THE SYSTEM COULD TRACK FURTHER TO THE SOUTH PER
12Z UKMET MODEL. STILL A LOT OF UNCERTAINTY WITH ULTIMATE TRACK.

WEDNESDAY...
A MID-LEVEL RIDGE WILL MOVE THROUGH THE REGION TUESDAY NIGHT INTO
EARLY WEDNESDAY LEADING TO A BRIEF RESPITE BETWEEN WEATHER SYSTEMS.
THEN A MID-LEVEL TROUGH IS PROJECTED TO BECOME NEGATIVELY TILTED
OVER THE OHIO VALLEY ON WED...LEADING TO A MERIDIONAL FLOW ALONG
THE EAST COAST...WITH THE ENTIRE COLUMN EXPECTED TO BE WELL ABOVE
FREEZING ACROSS THE CWA FAVORING A RAIN EVENT. THERE ARE SEVERAL
INGREDIENTS COMING TOGETHER FOR HEAVY RAIN. IN PARTICULAR...DEEP
GULF MOISTURE...LOW-LEVEL ISENTROPIC LIFT...MID-LEVEL PVA...AND
THE RIGHT-REAR QUADRANT OF A 140 KNOT UPPER-LEVEL JET JUST NORTH.
THE SYSTEM SHOULD BE FAIRLY PROGRESSIVE BUT WILL HAVE TO MONITOR
POTENTIAL FOR FLOODING.

THU AND FRI...
LOW-PRESSURE MOVES NORTHWARD INTO QUEBEC AND HIGH-PRESSURE BEGINS
TO BUILD IN. TEMPERATURES WILL RETURN TO SEASONABLE LEVELS AND
THERE COULD BE SNOW SHOWERS IN THE BLUSTERY NORTHWEST FLOW.

&&

.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

THE 00Z TAFS TAKE CIGS DOWN TO MVFR LEVELS TONIGHT FROM THE KPHL
AREA AIRPORTS NORTHWESTWARD WITH IMPROVEMENT ON SATURDAY. ITS BEEN
TOUGH TO SHAKE THIS STRATOCU LEVEL CLOUDINESS PATTERN.

FOR TONIGHT. LOW CLOUDS ADVANCING IN FROM THE HIGHER TERRAIN
AIRPORTS ARE STILL HEADING INTO THE TERMINALS. WE BRING MVFR CIG
POTENTIAL FROM THE GET GO AT KABE AND KRDG (HIER CONFIDENCE
OVERNIGHT) AND BRING IT DOWN TO THE KPHL METRO AIRPORTS AFTER 05Z.
WE LEAVE KACY AND KMIV VFR. WINDS WILL BE LIGHT FROM THE
NORTHWEST. NO VSBY RESTRICTIONS EXPECTED.

ON SATURDAY, PREDICTING THE MVFR CIG TO BECOME SCATTERED DURING
THE MORNING FROM THE KPHL METRO AIRPORTS NWWD WITH A CIRRUS CIG
ABOVE. KACY AND KMIV NOT EXPECTING A MVFR CIG. IT WILL BE A WEAK
PRESSURE PATTERN AND WINDS WILL BE LIGHT. A NORTHERLY DIRECTION
IS FAVORED, BUT SPEEDS ARE EXPECTED TO REMAIN BELOW 10 KNOTS,
PROBABLY PREDOMINATELY LESS THAN 6 KNOTS AT SOME OF THE MORE
RURAL AIRPORTS AND TERMINALS.

OUTLOOK...
SATURDAY NIGHT AND SUNDAY...VFR CONDITIONS EXPECTED.
MONDAY AND TUESDAY...IFR POSSIBLE IN SHRA AND SHSN.
WEDNESDAY...IFR POSSIBLE IN RAIN AND FOG.

&&

.MARINE...
SUB-SCA CONDS ARE EXPECTED FOR THE NEXT 24 HOURS AT LEAST. SMWHT
GUST NW WINDS THIS EVENING WILL GRADUALLY DIMINISH TONIGHT THROUGH
SATURDAY AS A RIDGE OF HIGH PRES MOVES OVERHEAD. SEAS ARE
CURRENTLY RUNNING 2 TO 3 FT BUT THEY SHOULD GRADUALLY DIMINISH
ALSO.

OUTLOOK...
SUNDAY AND MONDAY...SUB-SCA CONDITIONS EXPECTED.
TUESDAY...SCA MAY BE NEEDED FOR BUILDING SEAS.
WEDNESDAY...GALE WARNING MAY BE NEEDED.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANCK
NEAR TERM...GIGI
SHORT TERM...AMC
LONG TERM...FRANCK
AVIATION...FRANCK/GIGI
MARINE...AMC/FRANCK







000
FXUS61 KPHI 200240
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
940 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE JUST NORTH OF LAKE HURON WILL GRADUALLY MOVE
EASTWARD INTO NORTHERN NEW ENGLAND THRU MONDAY. A WAVE OF LOW
PRESSURE WILL FORM ALONG THE MID-ATLANTIC COASTLINE ON MONDAY AND
MOVE NORTHEASTWARD JUST OFFSHORE ON TUESDAY. A STRONG AREA OF
LOW PRESSURE WILL THEN FORM OVER THE MISSISSIPPI VALLEY AND MOVE
THRU THE GREAT LAKES REGION DURING THE MIDDLE OF THE
WEEK, BRINGING A STRONG COLD FRONT THRU THE REGION BY THURSDAY.
HIGH PRESSURE IS PROJECTED TO BUILD IN ON FRIDAY.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
LOW CLOUDS STILL WORKING THEIR WAY SOUTHWARD DEEPER INTO OUR CWA.
IT DOES FEEL LIKE WE ARE STUCK IN THE STRATOCUMULUS VERSION OF
GROUND HOG DAY. OVERNIGHT THERE IS A LOW LEVEL VORT MAX THAT IS
KEEPING THE LOW CLOUDS PERPETUATING AND JUST ENOUGH OF AN
INVERSION TO GIVE THEM A COMFORT LEVEL. IT LOOKS TO TAKE MOST OF
THE OVERNIGHT FOR THIS TO FEATURE TO CLEAR. LATER AT NIGHT SOME OF
THE CIRRUS FROM THE ONCE FORMIDABLE LOOKING SOUTHERN STREAM SYSTEM
WILL ALSO REACH OUR CWA.

OUR ADJUSTMENT WAS TO INCREASE CLOUD COVERAGE, ESP NORTH AND BUMP
UP MIN TEMPS THERE. IN THE SOUTHERN HALF OF OUR CWA, THE SHORT
WAVE TRAJ BYPASSES IT, SO WE WENT WITH A PTLY CLDY NIGHT. WINDS
ARE LIGHT ENOUGH THAT WE KEPT RADIATING MINS IN THE NJ PINE
BARRENS AND INTERIOR DELMARVA. THERE WILL BE SOME FROST SCRAPING
COME SATURDAY MORNING IN THOSE AREAS.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/...
FOR SATURDAY...HIGH PRES CENTERED OVER CANADA SHIFTS EWD FROM
ONTARIO INTO QUEBEC. A RIDGE AXIS IS FCST TO EXTEND SWD THROUGH THE
MID-ATLANTIC REGION RESULTING IN ONLY LIGHT NLY WINDS. SOME LOW-LVL
MOISTURE SHOULD REMAIN TRAPPED BELOW THE LARGE-SCALE SUBSIDENCE
INVERSION BUT HARD TO SAY HOW EXTENSIVE ANY LOW CLOUDS MAY BE. THE
12-KM NAM SHOWS A THIN LOW CLOUD LAYER DEVELOPING DURG THE DAY BUT
HIGHER-RES ARW/NMM AND THE GFS DO NOT. THERE WILL BE SOME HIGHER
CLOUDS ALSO ASSOCD WITH THE SHRTWV NOW MOVING ENEWD OUT OF THE SRN
PLAINS...HWVR POPS REMAIN NEAR ZERO.

&&

.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
HIGHLIGHTS...

* SLIGHT CHANCE OF SNOW SHOWERS SUNDAY MORNING MAINLY NORTH.
* SNOW POSSIBLE NORTHWEST OF THE I-95 CORRIDOR LATE MONDAY
  THRU EARLY TUESDAY.
* POTENTIAL FOR HEAVY RAIN INCREASING ON CHRISTMAS EVE DAY.

OVERVIEW...

MID-LEVEL BLOCKING PATTERN OVER NOAM BEGINS TO DISLODGE IN RESPONSE
JET ENERGY MOVING INTO THE PACIFIC NORTHWEST THIS WEEKEND...CARVING
OUT A DEEP TROUGH OVER THE MS VALLEY EARLY EARLY NEXT WEEK...WHICH
LEADS TO INCLEMENT WEATHER IN THE TUESDAY THRU WEDNESDAY TIME FRAME.

DETAILS...

SUNDAY...
SHORTWAVE LIFTING THROUGH THE REGION EARLY IN THE DAY MAY GENERATE
ENOUGH LIFT ALONG WITH MARGINAL MOISTURE IN THE COLUMN TO PRODUCE
SOME LIGHT SNOW SHOWERS...MAINLY DURING THE PRE-DAWN HOURS. LITTLE
IF ANY ACCUMULATION EXPECTED AS MOISTURE IS VERY LIMITED. RIDGING
THEN BUILDS IN SO FAIR WEATHER IS EXPECTED THE REMAINDER OF THE DAY.

MONDAY AND TUESDAY...
HIGH PRESSURE ANCHORS ALONG THE LEE OF THE APPALACHIANS. A SOUTHERN
STREAM SHORTWAVE WILL INDUCE LOW-PRESSURE OF THE MID-ATLANTIC COAST.
MODELS BRING QPF NORTHWARD INTO THE AREA ON MONDAY NIGHT INTO EARLY
TUESDAY. THERMAL PROFILES ARE COLD ENOUGH FOR SNOW TO THE NORTHWEST
OF THE I-95 CORRIDOR...BUT THE BEST LIFT IS FOCUSED JUST SOUTHEAST
OF THIS AREA...AND THE SYSTEM COULD TRACK FURTHER TO THE SOUTH PER
12Z UKMET MODEL. STILL A LOT OF UNCERTAINTY WITH ULTIMATE TRACK.

WEDNESDAY...
A MID-LEVEL RIDGE WILL MOVE THROUGH THE REGION TUESDAY NIGHT INTO
EARLY WEDNESDAY LEADING TO A BRIEF RESPITE BETWEEN WEATHER SYSTEMS.
THEN A MID-LEVEL TROUGH IS PROJECTED TO BECOME NEGATIVELY TILTED
OVER THE OHIO VALLEY ON WED...LEADING TO A MERIDIONAL FLOW ALONG
THE EAST COAST...WITH THE ENTIRE COLUMN EXPECTED TO BE WELL ABOVE
FREEZING ACROSS THE CWA FAVORING A RAIN EVENT. THERE ARE SEVERAL
INGREDIENTS COMING TOGETHER FOR HEAVY RAIN. IN PARTICULAR...DEEP
GULF MOISTURE...LOW-LEVEL ISENTROPIC LIFT...MID-LEVEL PVA...AND
THE RIGHT-REAR QUADRANT OF A 140 KNOT UPPER-LEVEL JET JUST NORTH.
THE SYSTEM SHOULD BE FAIRLY PROGRESSIVE BUT WILL HAVE TO MONITOR
POTENTIAL FOR FLOODING.

THU AND FRI...
LOW-PRESSURE MOVES NORTHWARD INTO QUEBEC AND HIGH-PRESSURE BEGINS
TO BUILD IN. TEMPERATURES WILL RETURN TO SEASONABLE LEVELS AND
THERE COULD BE SNOW SHOWERS IN THE BLUSTERY NORTHWEST FLOW.

&&

.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

THE 00Z TAFS TAKE CIGS DOWN TO MVFR LEVELS TONIGHT FROM THE KPHL
AREA AIRPORTS NORTHWESTWARD WITH IMPROVEMENT ON SATURDAY. ITS BEEN
TOUGH TO SHAKE THIS STRATOCU LEVEL CLOUDINESS PATTERN.

FOR TONIGHT. LOW CLOUDS ADVANCING IN FROM THE HIGHER TERRAIN
AIRPORTS ARE STILL HEADING INTO THE TERMINALS. WE BRING MVFR CIG
POTENTIAL FROM THE GET GO AT KABE AND KRDG (HIER CONFIDENCE
OVERNIGHT) AND BRING IT DOWN TO THE KPHL METRO AIRPORTS AFTER 05Z.
WE LEAVE KACY AND KMIV VFR. WINDS WILL BE LIGHT FROM THE
NORTHWEST. NO VSBY RESTRICTIONS EXPECTED.

ON SATURDAY, PREDICTING THE MVFR CIG TO BECOME SCATTERED DURING
THE MORNING FROM THE KPHL METRO AIRPORTS NWWD WITH A CIRRUS CIG
ABOVE. KACY AND KMIV NOT EXPECTING A MVFR CIG. IT WILL BE A WEAK
PRESSURE PATTERN AND WINDS WILL BE LIGHT. A NORTHERLY DIRECTION
IS FAVORED, BUT SPEEDS ARE EXPECTED TO REMAIN BELOW 10 KNOTS,
PROBABLY PREDOMINATELY LESS THAN 6 KNOTS AT SOME OF THE MORE
RURAL AIRPORTS AND TERMINALS.

OUTLOOK...
SATURDAY NIGHT AND SUNDAY...VFR CONDITIONS EXPECTED.
MONDAY AND TUESDAY...IFR POSSIBLE IN SHRA AND SHSN.
WEDNESDAY...IFR POSSIBLE IN RAIN AND FOG.

&&

.MARINE...
SUB-SCA CONDS ARE EXPECTED FOR THE NEXT 24 HOURS AT LEAST. SMWHT
GUST NW WINDS THIS EVENING WILL GRADUALLY DIMINISH TONIGHT THROUGH
SATURDAY AS A RIDGE OF HIGH PRES MOVES OVERHEAD. SEAS ARE
CURRENTLY RUNNING 2 TO 3 FT BUT THEY SHOULD GRADUALLY DIMINISH
ALSO.

OUTLOOK...
SUNDAY AND MONDAY...SUB-SCA CONDITIONS EXPECTED.
TUESDAY...SCA MAY BE NEEDED FOR BUILDING SEAS.
WEDNESDAY...GALE WARNING MAY BE NEEDED.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANCK
NEAR TERM...GIGI
SHORT TERM...AMC
LONG TERM...FRANCK
AVIATION...FRANCK/GIGI
MARINE...AMC/FRANCK







000
FXUS61 KPHI 200240
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
940 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE JUST NORTH OF LAKE HURON WILL GRADUALLY MOVE
EASTWARD INTO NORTHERN NEW ENGLAND THRU MONDAY. A WAVE OF LOW
PRESSURE WILL FORM ALONG THE MID-ATLANTIC COASTLINE ON MONDAY AND
MOVE NORTHEASTWARD JUST OFFSHORE ON TUESDAY. A STRONG AREA OF
LOW PRESSURE WILL THEN FORM OVER THE MISSISSIPPI VALLEY AND MOVE
THRU THE GREAT LAKES REGION DURING THE MIDDLE OF THE
WEEK, BRINGING A STRONG COLD FRONT THRU THE REGION BY THURSDAY.
HIGH PRESSURE IS PROJECTED TO BUILD IN ON FRIDAY.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
LOW CLOUDS STILL WORKING THEIR WAY SOUTHWARD DEEPER INTO OUR CWA.
IT DOES FEEL LIKE WE ARE STUCK IN THE STRATOCUMULUS VERSION OF
GROUND HOG DAY. OVERNIGHT THERE IS A LOW LEVEL VORT MAX THAT IS
KEEPING THE LOW CLOUDS PERPETUATING AND JUST ENOUGH OF AN
INVERSION TO GIVE THEM A COMFORT LEVEL. IT LOOKS TO TAKE MOST OF
THE OVERNIGHT FOR THIS TO FEATURE TO CLEAR. LATER AT NIGHT SOME OF
THE CIRRUS FROM THE ONCE FORMIDABLE LOOKING SOUTHERN STREAM SYSTEM
WILL ALSO REACH OUR CWA.

OUR ADJUSTMENT WAS TO INCREASE CLOUD COVERAGE, ESP NORTH AND BUMP
UP MIN TEMPS THERE. IN THE SOUTHERN HALF OF OUR CWA, THE SHORT
WAVE TRAJ BYPASSES IT, SO WE WENT WITH A PTLY CLDY NIGHT. WINDS
ARE LIGHT ENOUGH THAT WE KEPT RADIATING MINS IN THE NJ PINE
BARRENS AND INTERIOR DELMARVA. THERE WILL BE SOME FROST SCRAPING
COME SATURDAY MORNING IN THOSE AREAS.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/...
FOR SATURDAY...HIGH PRES CENTERED OVER CANADA SHIFTS EWD FROM
ONTARIO INTO QUEBEC. A RIDGE AXIS IS FCST TO EXTEND SWD THROUGH THE
MID-ATLANTIC REGION RESULTING IN ONLY LIGHT NLY WINDS. SOME LOW-LVL
MOISTURE SHOULD REMAIN TRAPPED BELOW THE LARGE-SCALE SUBSIDENCE
INVERSION BUT HARD TO SAY HOW EXTENSIVE ANY LOW CLOUDS MAY BE. THE
12-KM NAM SHOWS A THIN LOW CLOUD LAYER DEVELOPING DURG THE DAY BUT
HIGHER-RES ARW/NMM AND THE GFS DO NOT. THERE WILL BE SOME HIGHER
CLOUDS ALSO ASSOCD WITH THE SHRTWV NOW MOVING ENEWD OUT OF THE SRN
PLAINS...HWVR POPS REMAIN NEAR ZERO.

&&

.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
HIGHLIGHTS...

* SLIGHT CHANCE OF SNOW SHOWERS SUNDAY MORNING MAINLY NORTH.
* SNOW POSSIBLE NORTHWEST OF THE I-95 CORRIDOR LATE MONDAY
  THRU EARLY TUESDAY.
* POTENTIAL FOR HEAVY RAIN INCREASING ON CHRISTMAS EVE DAY.

OVERVIEW...

MID-LEVEL BLOCKING PATTERN OVER NOAM BEGINS TO DISLODGE IN RESPONSE
JET ENERGY MOVING INTO THE PACIFIC NORTHWEST THIS WEEKEND...CARVING
OUT A DEEP TROUGH OVER THE MS VALLEY EARLY EARLY NEXT WEEK...WHICH
LEADS TO INCLEMENT WEATHER IN THE TUESDAY THRU WEDNESDAY TIME FRAME.

DETAILS...

SUNDAY...
SHORTWAVE LIFTING THROUGH THE REGION EARLY IN THE DAY MAY GENERATE
ENOUGH LIFT ALONG WITH MARGINAL MOISTURE IN THE COLUMN TO PRODUCE
SOME LIGHT SNOW SHOWERS...MAINLY DURING THE PRE-DAWN HOURS. LITTLE
IF ANY ACCUMULATION EXPECTED AS MOISTURE IS VERY LIMITED. RIDGING
THEN BUILDS IN SO FAIR WEATHER IS EXPECTED THE REMAINDER OF THE DAY.

MONDAY AND TUESDAY...
HIGH PRESSURE ANCHORS ALONG THE LEE OF THE APPALACHIANS. A SOUTHERN
STREAM SHORTWAVE WILL INDUCE LOW-PRESSURE OF THE MID-ATLANTIC COAST.
MODELS BRING QPF NORTHWARD INTO THE AREA ON MONDAY NIGHT INTO EARLY
TUESDAY. THERMAL PROFILES ARE COLD ENOUGH FOR SNOW TO THE NORTHWEST
OF THE I-95 CORRIDOR...BUT THE BEST LIFT IS FOCUSED JUST SOUTHEAST
OF THIS AREA...AND THE SYSTEM COULD TRACK FURTHER TO THE SOUTH PER
12Z UKMET MODEL. STILL A LOT OF UNCERTAINTY WITH ULTIMATE TRACK.

WEDNESDAY...
A MID-LEVEL RIDGE WILL MOVE THROUGH THE REGION TUESDAY NIGHT INTO
EARLY WEDNESDAY LEADING TO A BRIEF RESPITE BETWEEN WEATHER SYSTEMS.
THEN A MID-LEVEL TROUGH IS PROJECTED TO BECOME NEGATIVELY TILTED
OVER THE OHIO VALLEY ON WED...LEADING TO A MERIDIONAL FLOW ALONG
THE EAST COAST...WITH THE ENTIRE COLUMN EXPECTED TO BE WELL ABOVE
FREEZING ACROSS THE CWA FAVORING A RAIN EVENT. THERE ARE SEVERAL
INGREDIENTS COMING TOGETHER FOR HEAVY RAIN. IN PARTICULAR...DEEP
GULF MOISTURE...LOW-LEVEL ISENTROPIC LIFT...MID-LEVEL PVA...AND
THE RIGHT-REAR QUADRANT OF A 140 KNOT UPPER-LEVEL JET JUST NORTH.
THE SYSTEM SHOULD BE FAIRLY PROGRESSIVE BUT WILL HAVE TO MONITOR
POTENTIAL FOR FLOODING.

THU AND FRI...
LOW-PRESSURE MOVES NORTHWARD INTO QUEBEC AND HIGH-PRESSURE BEGINS
TO BUILD IN. TEMPERATURES WILL RETURN TO SEASONABLE LEVELS AND
THERE COULD BE SNOW SHOWERS IN THE BLUSTERY NORTHWEST FLOW.

&&

.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

THE 00Z TAFS TAKE CIGS DOWN TO MVFR LEVELS TONIGHT FROM THE KPHL
AREA AIRPORTS NORTHWESTWARD WITH IMPROVEMENT ON SATURDAY. ITS BEEN
TOUGH TO SHAKE THIS STRATOCU LEVEL CLOUDINESS PATTERN.

FOR TONIGHT. LOW CLOUDS ADVANCING IN FROM THE HIGHER TERRAIN
AIRPORTS ARE STILL HEADING INTO THE TERMINALS. WE BRING MVFR CIG
POTENTIAL FROM THE GET GO AT KABE AND KRDG (HIER CONFIDENCE
OVERNIGHT) AND BRING IT DOWN TO THE KPHL METRO AIRPORTS AFTER 05Z.
WE LEAVE KACY AND KMIV VFR. WINDS WILL BE LIGHT FROM THE
NORTHWEST. NO VSBY RESTRICTIONS EXPECTED.

ON SATURDAY, PREDICTING THE MVFR CIG TO BECOME SCATTERED DURING
THE MORNING FROM THE KPHL METRO AIRPORTS NWWD WITH A CIRRUS CIG
ABOVE. KACY AND KMIV NOT EXPECTING A MVFR CIG. IT WILL BE A WEAK
PRESSURE PATTERN AND WINDS WILL BE LIGHT. A NORTHERLY DIRECTION
IS FAVORED, BUT SPEEDS ARE EXPECTED TO REMAIN BELOW 10 KNOTS,
PROBABLY PREDOMINATELY LESS THAN 6 KNOTS AT SOME OF THE MORE
RURAL AIRPORTS AND TERMINALS.

OUTLOOK...
SATURDAY NIGHT AND SUNDAY...VFR CONDITIONS EXPECTED.
MONDAY AND TUESDAY...IFR POSSIBLE IN SHRA AND SHSN.
WEDNESDAY...IFR POSSIBLE IN RAIN AND FOG.

&&

.MARINE...
SUB-SCA CONDS ARE EXPECTED FOR THE NEXT 24 HOURS AT LEAST. SMWHT
GUST NW WINDS THIS EVENING WILL GRADUALLY DIMINISH TONIGHT THROUGH
SATURDAY AS A RIDGE OF HIGH PRES MOVES OVERHEAD. SEAS ARE
CURRENTLY RUNNING 2 TO 3 FT BUT THEY SHOULD GRADUALLY DIMINISH
ALSO.

OUTLOOK...
SUNDAY AND MONDAY...SUB-SCA CONDITIONS EXPECTED.
TUESDAY...SCA MAY BE NEEDED FOR BUILDING SEAS.
WEDNESDAY...GALE WARNING MAY BE NEEDED.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANCK
NEAR TERM...GIGI
SHORT TERM...AMC
LONG TERM...FRANCK
AVIATION...FRANCK/GIGI
MARINE...AMC/FRANCK







000
FXUS61 KCTP 200237
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
937 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER THE WESTERN GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND...BRINGING DRY WEATHER WITH
LIGHTER WIND. A DEEP UPPER TROUGH AND ASSOCIATED SFC LOW WILL LIFT
NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE OF NEXT WEEK
LIKELY BRINGING US RAIN AND WIND FOR CHRISTMAS EVE...THEN BLUSTERY
AND COLDER CONDITIONS FOR CHRISTMAS DAY WITH SCATTERED SNOW
SHOWERS.

&&

.NEAR TERM /UNTIL 8 AM SATURDAY MORNING/...
930 PM UPDATE...
CLOUDS AND TEMPS BEHAVING. NO NEED FOR ANYTHING OTHER THAN TINY
TWEAKS.

7 PM UPDATE...
BIG BREAKS IN CLOUDS LOCALLY. NRLY FLOW IS SHOVING THE CLOUDS DOWN
INTO THE POCONOS AND TRYING TO GET THEM INTO LEB/LANC COS. AT THIS
POINT...WILL CONTINUE TO COUNT ON THE DOWNSLOPE TO KEEP IT FROM
GOING TOTALLY OVC...BUT SOME INCREASE IN CLOUDS OVER THE NEXT FEW
HRS IN THE SE IS PROBABLY A GOOD CALL. OTHERWISE...THE SUBSIDENCE
IN BETWEEN THE NERN AND SERN PARTS OF THE STATE MAY CONTINUE TO
OPEN UP BIGGER BREAKS. WILL HAVE TO TWEAK NWRN MIN TEMPS AS THEY
ARE EXTREMELY CLOSE TO GOING MINS ATTM. ELSEWHERE...DEWPOINTS AND
ONLY SLOW DECREASE IN COVG LOOK LIKE THE MINS ARE OKAY FOR NOW.

PREV...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK TRAPPED BELOW A
MODERATELY STRONG SUBSIDENCE INVERSION /BASED AT AROUND 2-3KFT
AGL/ WILL PERSIST ACROSS MUCH OF NORTHERN AND WESTERN PENNSYLVANIA
LATE TODAY INTO SATURDAY...WHILE PARTIAL CLEARING OCCURS ACROSS
THE LOWER SUSQ VALLEY AND SURROUNDING AREAS.

TEMPS WILL REMAIN STEADY THROUGH LATE THIS AFTERNOON UNDER THE
10-15 KT NWRLY FLOW. READINGS WILL VARY FROM THE MID TO UPPER 20S
ACROSS THE NORTHERN AND WESTERN MOUNTAINS...TO THE LOWER 40S IN
THE SOUTHEAST.

A WEAK SFC RIDGE WILL MOVE TO NEAR THE PENN/OHIO BORDER BY 12Z
SATURDAY...BUT THE WEAK WESTERLY ISENTROPIC LIFT ALONG THE 285K
THETA SFC...AND SOME SHALLOW MOISTURE BEING ADVECTED SWD INTO THE
NRN MTNS OF PENN FROM LAKE ONTARIO...WILL MAINTAIN MOSTLY CLOUDY
TO CLOUDY SKIES. LITTLE MORE THAN A FEW FLURRIES OR SPOTTY -FZDZ
WILL FALL FROM THIS THIN CLOUD LAYER ACROSS THE HIGHER TERRAIN OF
THE LAURELS AND INVOF KBFD.

AFTER A PTLY CLOUDY LATE AFTERNOON AND EVENING IN THE SE PART OF
THE CWA...A BKN LAYER OF STRATO CU IS EXPECTED TO DRIFT SE /OR
FORM/ ACROSS THE REGION OVERNIGHT.

DUE TO THE NW-SE GRADIENT OF DECREASING CLOUDS...LOW TEMPS AT
DAYBREAK SAT WILL BE IN A RATHER TIGHT RANGE...FROM THE UPPER
TEENS TO LOWER 20S ACROSS THE MOUNTAINS...TO THE LOWER 20S IN THE
SE

&&

.SHORT TERM /8 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
A RIDGE OF HIGH PRESSURE...LIGHTER WIND...AND ASSOC DRIER AIR
MASS WILL BUILD EAST ACROSS THE STATE SATURDAY...PROVIDING THE
AREA WITH FAIR WEATHER.

HIGH RES MODEL DATA CONTINUES TO PAINT A MOSTLY CLOUDY PICTURE FOR
MUCH OF THE REGION SATURDAY INTO SATURDAY NIGHT...THOUGH PERIODS
OF SUNSHINE ARE LIKELY THROUGHOUT THE CENTRAL RIDGE AND VALLEY
REGION...AND SUSQUEHANNA RIVER VALLEY.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS OVER THE LOWER/THIN STRATO CU
CLOUD DECK PRESENT ACROSS THE REGION SATURDAY. ALL 12Z OPERATIONAL
MODEL DATA CONTINUES TO SUPPORT A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS NEAR 30 ACROSS THE MTNS...AND MID TO UPPER 30S IN
THE SE.

MOSTLY CLOUDY SKIES WITH LIGHT WIND SAT NIGHT WILL YIELD LOWS IN
THE LOWER 20S ACROSS THE MTNS...AND GENERALLY THE MID 20S
ELSEWHERE.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGH PRES WILL PROVIDE TRANQUIL WEATHER ON SUNDAY...WITH PARTLY TO
MOSTLY SUNNY SKIES AND SEASONABLE TEMPS. AFTER THAT...THE WEATHER
WILL BECOME INCREASINGLY UNSETTLED AS NEXT WEEK PROGRESSES.

CLOUDS WILL INCR SUNDAY NIGHT INTO MONDAY...AS HIGH PRES LOSES
ITS GRIP AND A WEAK AREA OF LOW PRES ORGANIZES OVER THE SERN UNITED
STATES. LIGHT PRECIP WILL WORK NWD INTO PENNSYLVANIA LATE MONDAY
INTO MONDAY NIGHT AND CONTINUE INTO TUES. INITIALLY...CONDS WILL
BE COLD ENOUGH FOR THE POSSIBILITY OF SOME WINTRY PRECIP.
HOWEVER...WARMER AIR WILL MAKE ITS WAY NWD LATER MONDAY NIGHT INTO
TUES AND GRADUALLY CHANGE ANY LINGERING PRECIP OVER TO PLAIN RAIN.

A MORE SIGNIFICANT STORM SYSTEM WILL GET ORGANIZED OVER THE
MISSISSIPPI VALLEY TUES NIGHT BEFORE PUSHING NWD INTO THE GREAT
LAKES ON WED. THIS SYSTEM WILL DRAW EVEN MILDER AIR NWD INTO THE
REGION...AND PROVIDE A RAINY AND BREEZY CHRISTMAS EVE DAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS FROM WEST TO EAST ACROSS PA IS POSSIBLE LATE WED/WED
NIGHT. SCT SNOW SHOWERS WILL CONTINUE INTO THURS ACROSS MAINLY
NRN AND WRN PA.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
OPERATIONAL MODELS AND THE GEFS SHOWING 850HPA TEMPS ALREADY
BEGINNING TO RISE NEXT FRI.

&&

.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
LLVL NWRLY FLOW AND OROGRAPHIC FORCING OF A SHALLOW MOIST LAYER
WILL CONTINUE TO PRODUCE PLENTY OF CLOUDS ACROSS THE NW 1/2 TO
2/3RDS OF THE STATE WITH MAINLY MVFR BKN-OVC CIGS THROUGH
TONIGHT. KJST AND KBFD MAY TEETER ON THE UPPER END OF IFR FOR A
FEW HOURS LATER TONIGHT /AFTER 06Z/. IN CONTRAST...THE SE PENN
AIRFIELDS SUCH AS KMDT...KTHV AND KLNS WILL SEE MAINLY VFR...WITH
SKY CONDITIONS VARYING SCT-BKN030-040.

NORTHWEST WINDS OF 10-15 KTS WITH HIGHER GUSTS WILL DECREASE TO 8
KTS OR LESS LATER TONIGHT AND SATURDAY.

HIGH PRESSURE BUILDS EAST ACROSS PENN SATURDAY...WITH BKN-OVC CIGS
VARYING BETWEEN MVFR OVER THE HIGHER TERRAIN OF THE NORTH AND
WEST...TO SCT-BKN VFR IN THE VALLEYS.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...EVANEGO
AVIATION...LAMBERT/CERU




000
FXUS61 KCTP 200237
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
937 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER THE WESTERN GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND...BRINGING DRY WEATHER WITH
LIGHTER WIND. A DEEP UPPER TROUGH AND ASSOCIATED SFC LOW WILL LIFT
NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE OF NEXT WEEK
LIKELY BRINGING US RAIN AND WIND FOR CHRISTMAS EVE...THEN BLUSTERY
AND COLDER CONDITIONS FOR CHRISTMAS DAY WITH SCATTERED SNOW
SHOWERS.

&&

.NEAR TERM /UNTIL 8 AM SATURDAY MORNING/...
930 PM UPDATE...
CLOUDS AND TEMPS BEHAVING. NO NEED FOR ANYTHING OTHER THAN TINY
TWEAKS.

7 PM UPDATE...
BIG BREAKS IN CLOUDS LOCALLY. NRLY FLOW IS SHOVING THE CLOUDS DOWN
INTO THE POCONOS AND TRYING TO GET THEM INTO LEB/LANC COS. AT THIS
POINT...WILL CONTINUE TO COUNT ON THE DOWNSLOPE TO KEEP IT FROM
GOING TOTALLY OVC...BUT SOME INCREASE IN CLOUDS OVER THE NEXT FEW
HRS IN THE SE IS PROBABLY A GOOD CALL. OTHERWISE...THE SUBSIDENCE
IN BETWEEN THE NERN AND SERN PARTS OF THE STATE MAY CONTINUE TO
OPEN UP BIGGER BREAKS. WILL HAVE TO TWEAK NWRN MIN TEMPS AS THEY
ARE EXTREMELY CLOSE TO GOING MINS ATTM. ELSEWHERE...DEWPOINTS AND
ONLY SLOW DECREASE IN COVG LOOK LIKE THE MINS ARE OKAY FOR NOW.

PREV...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK TRAPPED BELOW A
MODERATELY STRONG SUBSIDENCE INVERSION /BASED AT AROUND 2-3KFT
AGL/ WILL PERSIST ACROSS MUCH OF NORTHERN AND WESTERN PENNSYLVANIA
LATE TODAY INTO SATURDAY...WHILE PARTIAL CLEARING OCCURS ACROSS
THE LOWER SUSQ VALLEY AND SURROUNDING AREAS.

TEMPS WILL REMAIN STEADY THROUGH LATE THIS AFTERNOON UNDER THE
10-15 KT NWRLY FLOW. READINGS WILL VARY FROM THE MID TO UPPER 20S
ACROSS THE NORTHERN AND WESTERN MOUNTAINS...TO THE LOWER 40S IN
THE SOUTHEAST.

A WEAK SFC RIDGE WILL MOVE TO NEAR THE PENN/OHIO BORDER BY 12Z
SATURDAY...BUT THE WEAK WESTERLY ISENTROPIC LIFT ALONG THE 285K
THETA SFC...AND SOME SHALLOW MOISTURE BEING ADVECTED SWD INTO THE
NRN MTNS OF PENN FROM LAKE ONTARIO...WILL MAINTAIN MOSTLY CLOUDY
TO CLOUDY SKIES. LITTLE MORE THAN A FEW FLURRIES OR SPOTTY -FZDZ
WILL FALL FROM THIS THIN CLOUD LAYER ACROSS THE HIGHER TERRAIN OF
THE LAURELS AND INVOF KBFD.

AFTER A PTLY CLOUDY LATE AFTERNOON AND EVENING IN THE SE PART OF
THE CWA...A BKN LAYER OF STRATO CU IS EXPECTED TO DRIFT SE /OR
FORM/ ACROSS THE REGION OVERNIGHT.

DUE TO THE NW-SE GRADIENT OF DECREASING CLOUDS...LOW TEMPS AT
DAYBREAK SAT WILL BE IN A RATHER TIGHT RANGE...FROM THE UPPER
TEENS TO LOWER 20S ACROSS THE MOUNTAINS...TO THE LOWER 20S IN THE
SE

&&

.SHORT TERM /8 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
A RIDGE OF HIGH PRESSURE...LIGHTER WIND...AND ASSOC DRIER AIR
MASS WILL BUILD EAST ACROSS THE STATE SATURDAY...PROVIDING THE
AREA WITH FAIR WEATHER.

HIGH RES MODEL DATA CONTINUES TO PAINT A MOSTLY CLOUDY PICTURE FOR
MUCH OF THE REGION SATURDAY INTO SATURDAY NIGHT...THOUGH PERIODS
OF SUNSHINE ARE LIKELY THROUGHOUT THE CENTRAL RIDGE AND VALLEY
REGION...AND SUSQUEHANNA RIVER VALLEY.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS OVER THE LOWER/THIN STRATO CU
CLOUD DECK PRESENT ACROSS THE REGION SATURDAY. ALL 12Z OPERATIONAL
MODEL DATA CONTINUES TO SUPPORT A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS NEAR 30 ACROSS THE MTNS...AND MID TO UPPER 30S IN
THE SE.

MOSTLY CLOUDY SKIES WITH LIGHT WIND SAT NIGHT WILL YIELD LOWS IN
THE LOWER 20S ACROSS THE MTNS...AND GENERALLY THE MID 20S
ELSEWHERE.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGH PRES WILL PROVIDE TRANQUIL WEATHER ON SUNDAY...WITH PARTLY TO
MOSTLY SUNNY SKIES AND SEASONABLE TEMPS. AFTER THAT...THE WEATHER
WILL BECOME INCREASINGLY UNSETTLED AS NEXT WEEK PROGRESSES.

CLOUDS WILL INCR SUNDAY NIGHT INTO MONDAY...AS HIGH PRES LOSES
ITS GRIP AND A WEAK AREA OF LOW PRES ORGANIZES OVER THE SERN UNITED
STATES. LIGHT PRECIP WILL WORK NWD INTO PENNSYLVANIA LATE MONDAY
INTO MONDAY NIGHT AND CONTINUE INTO TUES. INITIALLY...CONDS WILL
BE COLD ENOUGH FOR THE POSSIBILITY OF SOME WINTRY PRECIP.
HOWEVER...WARMER AIR WILL MAKE ITS WAY NWD LATER MONDAY NIGHT INTO
TUES AND GRADUALLY CHANGE ANY LINGERING PRECIP OVER TO PLAIN RAIN.

A MORE SIGNIFICANT STORM SYSTEM WILL GET ORGANIZED OVER THE
MISSISSIPPI VALLEY TUES NIGHT BEFORE PUSHING NWD INTO THE GREAT
LAKES ON WED. THIS SYSTEM WILL DRAW EVEN MILDER AIR NWD INTO THE
REGION...AND PROVIDE A RAINY AND BREEZY CHRISTMAS EVE DAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS FROM WEST TO EAST ACROSS PA IS POSSIBLE LATE WED/WED
NIGHT. SCT SNOW SHOWERS WILL CONTINUE INTO THURS ACROSS MAINLY
NRN AND WRN PA.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
OPERATIONAL MODELS AND THE GEFS SHOWING 850HPA TEMPS ALREADY
BEGINNING TO RISE NEXT FRI.

&&

.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
LLVL NWRLY FLOW AND OROGRAPHIC FORCING OF A SHALLOW MOIST LAYER
WILL CONTINUE TO PRODUCE PLENTY OF CLOUDS ACROSS THE NW 1/2 TO
2/3RDS OF THE STATE WITH MAINLY MVFR BKN-OVC CIGS THROUGH
TONIGHT. KJST AND KBFD MAY TEETER ON THE UPPER END OF IFR FOR A
FEW HOURS LATER TONIGHT /AFTER 06Z/. IN CONTRAST...THE SE PENN
AIRFIELDS SUCH AS KMDT...KTHV AND KLNS WILL SEE MAINLY VFR...WITH
SKY CONDITIONS VARYING SCT-BKN030-040.

NORTHWEST WINDS OF 10-15 KTS WITH HIGHER GUSTS WILL DECREASE TO 8
KTS OR LESS LATER TONIGHT AND SATURDAY.

HIGH PRESSURE BUILDS EAST ACROSS PENN SATURDAY...WITH BKN-OVC CIGS
VARYING BETWEEN MVFR OVER THE HIGHER TERRAIN OF THE NORTH AND
WEST...TO SCT-BKN VFR IN THE VALLEYS.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...EVANEGO
AVIATION...LAMBERT/CERU



000
FXUS61 KPBZ 200225
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
925 PM EST FRI DEC 19 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
WITH 930PM UPDATE...INCREASED SKY COVER OVERNIGHT AS WELL AS
MAKING MINOR ADJUSTMENTS TO OVERNIGHT TEMPERATURES. WHILE STRATUS
SCATTERED OUT SOMEWHAT EARLIER THIS EVENING NEAR FRANKLIN AND
DUBOIS...THIS GAP HAS FILLED BACK IN...AND DO NOT EXPECT MUCH IF
ANY ADDITIONAL CLEARING THIS EVENING. AS A RESULT...TEMPERATURES
FELL SLIGHTLY MORE TO THE NORTH WITH THE REST OF THE REGION
STAYING A BIT WARMER. HAVE REFLECTED THAT TREND IN THE OVERNIGHT
LOWS...ALTHOUGH THIS SHOULD NOT CHANGE VALUES BY MORE THAN A
COUPLE DEGREES.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
HIGH PRESSURE RIDGE WILL SETTLE OVER THE NORTHEASTERN CONUS FOR
MUCH OF THE WEEKEND. A FAST MOVING SYSTEM WILL BE SUPPRESSED TO
THE SOUTH SATURDAY BUT SOME MID-HIGH DECK MAY REPLACE THE LOW
DECK...MAINTAINING MOSTLY CLOUDY SKIES THROUGH MUCH OF THE DAY.
WITH NEARLY STAGNANT 850HPA TEMPERATURES AND MINIMAL SUN
TOMORROW...EXPECT HIGHS WILL NOT SURPASS THE LOW TO MID 30`S.
HOWEVER...SOUTHERLY FLOW AND WARM ADVECTION WILL RETURN FOR SUNDAY
AND MONDAY BRINGING TEMPERATURES TO NEAR OR JUST ABOVE NORMAL
VALUES.

ON MONDAY...WE WILL BE IN THE SQUEEZE BETWEEN TWO SYSTEMS. ONE LOW
WILL BE DEVELOPING ALONG THE GULF COAST...WHILE ANOTHER LOW AND
DEEPENING UPPER TROUGH WILL SINK SOUTHWARD OVER THE CENTRAL US.
THIS LOW OVER THE CENTRAL PLAINS WILL HELP TO AMPLIFY THE UPPER
PATTERN...EJECTING THE SOUTHERN SYSTEM NORTHWARD. AT THIS POINT
THE BULK OF THE MOISTURE WITH THE SOUTHERN SYSTEM SHOULD REMAIN
EAST...JUST BRUSHING OUR EASTERN MOUNTAINS OF WV/MD UNTIL THE COLD
FRONT WITH THE DEEPENING LOW APPROACHES. MAINTAINED CHANCE POPS
FOR THE RIDGES WITH LOWER POPS FURTHER NORTH AND WEST THROUGH
MONDAY. WHILE THE MID LEVELS WILL BE WARMING...CANNOT RULE OUT A
RAIN/SNOW MIX INITIALLY MONDAY MORNING OVER THE RIDGES BEFORE
CHANGING TO ALL RAIN. SOME FREEZING RAIN COULD ALSO BE OF CONCERN
IN ANY SHELTERED VALLEYS...BUT FOR NOW WILL LEAVE THIS OUT.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MODELS ARE IN GENERAL AGREEMENT ON DEEPENING UPPER LEVEL CLOSED LOW
OVER THE GREAT LAKES TUESDAY THROUGH THURSDAY WITH PERIODS OF RAIN
INTO WEDNESDAY UNTIL COLD FRONT WILL CHANGE PRECIP OVER TO SNOW
SHOWERS LATER WEDNESDAY AND THURSDAY. WINDS WILL BE ON THE
INCREASE THURSDAY AS SURFACE LOW WRAPS UP NORTH OF THE REGION. QPF
ON THE FRONT SIDE OF SYSTEM WILL BE NEAR AN INCH...WHICH SHOULD
NOT PRODUCE ANY SIGNIFICANT PROBLEMS. BACKLASH SNOW WEDNESDAY
NIGHT INTO THURSDAY WILL BE LIGHT WITH ONLY MINOR ACCUMULATIONS
EXPECTED. FLOW BEHIND COLD FRONT LOOKS TO STAY SOUTHWESTERLY WHICH
LOOKS TO LIMIT LAKE ENHANCED AMOUNTS ALONG I-80 AND THE RIDGES.
COLDER TEMPERATURES WILL THEN MODERATE FRIDAY AS MID LEVEL FLOW
QUICKLY BECOMES ZONAL.

&&

.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
PERVASIVE STRATUS COVERS ALL SITES THIS EVENING...WHILE BOUNDARY
LAYER MOISTURE HAS DROPPED OFF FROM EARLIER TODAY. GIVEN STRONG
INVERSIONS...STRATUS SEEMS LIKELY TO CONTINUE FOR THE NEXT DAY AT
LEAST...HOWEVER GIVEN A BIT WIDER DEWPOINT DEPRESSIONS...LIGHT
PRECIPITATION CHANCES SEEM VERY LOW. MVFR CONDITIONS SEEM LIKELY
TO CONTINUE. FRIES


OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY AND WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$







000
FXUS61 KPBZ 200225
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
925 PM EST FRI DEC 19 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
WITH 930PM UPDATE...INCREASED SKY COVER OVERNIGHT AS WELL AS
MAKING MINOR ADJUSTMENTS TO OVERNIGHT TEMPERATURES. WHILE STRATUS
SCATTERED OUT SOMEWHAT EARLIER THIS EVENING NEAR FRANKLIN AND
DUBOIS...THIS GAP HAS FILLED BACK IN...AND DO NOT EXPECT MUCH IF
ANY ADDITIONAL CLEARING THIS EVENING. AS A RESULT...TEMPERATURES
FELL SLIGHTLY MORE TO THE NORTH WITH THE REST OF THE REGION
STAYING A BIT WARMER. HAVE REFLECTED THAT TREND IN THE OVERNIGHT
LOWS...ALTHOUGH THIS SHOULD NOT CHANGE VALUES BY MORE THAN A
COUPLE DEGREES.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
HIGH PRESSURE RIDGE WILL SETTLE OVER THE NORTHEASTERN CONUS FOR
MUCH OF THE WEEKEND. A FAST MOVING SYSTEM WILL BE SUPPRESSED TO
THE SOUTH SATURDAY BUT SOME MID-HIGH DECK MAY REPLACE THE LOW
DECK...MAINTAINING MOSTLY CLOUDY SKIES THROUGH MUCH OF THE DAY.
WITH NEARLY STAGNANT 850HPA TEMPERATURES AND MINIMAL SUN
TOMORROW...EXPECT HIGHS WILL NOT SURPASS THE LOW TO MID 30`S.
HOWEVER...SOUTHERLY FLOW AND WARM ADVECTION WILL RETURN FOR SUNDAY
AND MONDAY BRINGING TEMPERATURES TO NEAR OR JUST ABOVE NORMAL
VALUES.

ON MONDAY...WE WILL BE IN THE SQUEEZE BETWEEN TWO SYSTEMS. ONE LOW
WILL BE DEVELOPING ALONG THE GULF COAST...WHILE ANOTHER LOW AND
DEEPENING UPPER TROUGH WILL SINK SOUTHWARD OVER THE CENTRAL US.
THIS LOW OVER THE CENTRAL PLAINS WILL HELP TO AMPLIFY THE UPPER
PATTERN...EJECTING THE SOUTHERN SYSTEM NORTHWARD. AT THIS POINT
THE BULK OF THE MOISTURE WITH THE SOUTHERN SYSTEM SHOULD REMAIN
EAST...JUST BRUSHING OUR EASTERN MOUNTAINS OF WV/MD UNTIL THE COLD
FRONT WITH THE DEEPENING LOW APPROACHES. MAINTAINED CHANCE POPS
FOR THE RIDGES WITH LOWER POPS FURTHER NORTH AND WEST THROUGH
MONDAY. WHILE THE MID LEVELS WILL BE WARMING...CANNOT RULE OUT A
RAIN/SNOW MIX INITIALLY MONDAY MORNING OVER THE RIDGES BEFORE
CHANGING TO ALL RAIN. SOME FREEZING RAIN COULD ALSO BE OF CONCERN
IN ANY SHELTERED VALLEYS...BUT FOR NOW WILL LEAVE THIS OUT.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MODELS ARE IN GENERAL AGREEMENT ON DEEPENING UPPER LEVEL CLOSED LOW
OVER THE GREAT LAKES TUESDAY THROUGH THURSDAY WITH PERIODS OF RAIN
INTO WEDNESDAY UNTIL COLD FRONT WILL CHANGE PRECIP OVER TO SNOW
SHOWERS LATER WEDNESDAY AND THURSDAY. WINDS WILL BE ON THE
INCREASE THURSDAY AS SURFACE LOW WRAPS UP NORTH OF THE REGION. QPF
ON THE FRONT SIDE OF SYSTEM WILL BE NEAR AN INCH...WHICH SHOULD
NOT PRODUCE ANY SIGNIFICANT PROBLEMS. BACKLASH SNOW WEDNESDAY
NIGHT INTO THURSDAY WILL BE LIGHT WITH ONLY MINOR ACCUMULATIONS
EXPECTED. FLOW BEHIND COLD FRONT LOOKS TO STAY SOUTHWESTERLY WHICH
LOOKS TO LIMIT LAKE ENHANCED AMOUNTS ALONG I-80 AND THE RIDGES.
COLDER TEMPERATURES WILL THEN MODERATE FRIDAY AS MID LEVEL FLOW
QUICKLY BECOMES ZONAL.

&&

.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
PERVASIVE STRATUS COVERS ALL SITES THIS EVENING...WHILE BOUNDARY
LAYER MOISTURE HAS DROPPED OFF FROM EARLIER TODAY. GIVEN STRONG
INVERSIONS...STRATUS SEEMS LIKELY TO CONTINUE FOR THE NEXT DAY AT
LEAST...HOWEVER GIVEN A BIT WIDER DEWPOINT DEPRESSIONS...LIGHT
PRECIPITATION CHANCES SEEM VERY LOW. MVFR CONDITIONS SEEM LIKELY
TO CONTINUE. FRIES


OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY AND WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$






000
FXUS61 KCTP 200000
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
700 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER THE WESTERN GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND...BRINGING DRY WEATHER WITH
LIGHTER WIND. A DEEP UPPER TROUGH AND ASSOCIATED SFC LOW WILL LIFT
NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE OF NEXT WEEK
LIKELY BRINGING US RAIN AND WIND FOR CHRISTMAS EVE...THEN BLUSTERY
AND COLDER CONDITIONS FOR CHRISTMAS DAY WITH SCATTERED SNOW
SHOWERS.

&&

.NEAR TERM /UNTIL 7 AM SATURDAY MORNING/...
7 PM UPDATE...
BIG BREAKS IN CLOUDS LOCALLY. NRLY FLOW IS SHOVING THE CLOUDS DOWN
INTO THE POCONOS AND TRYING TO GET THEM INTO LEB/LANC COS. AT THIS
POINT...WILL CONTINUE TO COUNT ON THE DOWNSLOPE TO KEEP IT FROM
GOING TOTALLY OVC...BUT SOME INCREASE IN CLOUDS OVER THE NEXT FEW
HRS IN THE SE IS PROBABLY A GOOD CALL. OTHERWISE...THE SUBSIDENCE
IN BETWEEN THE NERN AND SERN PARTS OF THE STATE MAY CONTINUE TO
OPEN UP BIGGER BREAKS. WILL HAVE TO TWEAK NWRN MIN TEMPS AS THEY
ARE EXTREMELY CLOSE TO GOING MINS ATTM. ELSEWHERE...DEWPOINTS AND
ONLY SLOW DECREASE IN COVG LOOK LIKE THE MINS ARE OKAY FOR NOW.

PREV...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK TRAPPED BELOW A
MODERATELY STRONG SUBSIDENCE INVERSION /BASED AT AROUND 2-3KFT
AGL/ WILL PERSIST ACROSS MUCH OF NORTHERN AND WESTERN PENNSYLVANIA
LATE TODAY INTO SATURDAY...WHILE PARTIAL CLEARING OCCURS ACROSS
THE LOWER SUSQ VALLEY AND SURROUNDING AREAS.

TEMPS WILL REMAIN STEADY THROUGH LATE THIS AFTERNOON UNDER THE
10-15 KT NWRLY FLOW. READINGS WILL VARY FROM THE MID TO UPPER 20S
ACROSS THE NORTHERN AND WESTERN MOUNTAINS...TO THE LOWER 40S IN
THE SOUTHEAST.

A WEAK SFC RIDGE WILL MOVE TO NEAR THE PENN/OHIO BORDER BY 12Z
SATURDAY...BUT THE WEAK WESTERLY ISENTROPIC LIFT ALONG THE 285K
THETA SFC...AND SOME SHALLOW MOISTURE BEING ADVECTED SWD INTO THE
NRN MTNS OF PENN FROM LAKE ONTARIO...WILL MAINTAIN MOSTLY CLOUDY
TO CLOUDY SKIES. LITTLE MORE THAN A FEW FLURRIES OR SPOTTY -FZDZ
WILL FALL FROM THIS THIN CLOUD LAYER ACROSS THE HIGHER TERRAIN OF
THE LAURELS AND INVOF KBFD.

AFTER A PTLY CLOUDY LATE AFTERNOON AND EVENING IN THE SE PART OF
THE CWA...A BKN LAYER OF STRATO CU IS EXPECTED TO DRIFT SE /OR
FORM/ ACROSS THE REGION OVERNIGHT.

DUE TO THE NW-SE GRADIENT OF DECREASING CLOUDS...LOW TEMPS AT
DAYBREAK SAT WILL BE IN A RATHER TIGHT RANGE...FROM THE UPPER
TEENS TO LOWER 20S ACROSS THE MOUNTAINS...TO THE LOWER 20S IN THE
SE

&&

.SHORT TERM /7 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
A RIDGE OF HIGH PRESSURE...LIGHTER WIND...AND ASSOC DRIER AIR
MASS WILL BUILD EAST ACROSS THE STATE SATURDAY...PROVIDING THE
AREA WITH FAIR WEATHER.

HIGH RES MODEL DATA CONTINUES TO PAINT A MOSTLY CLOUDY PICTURE FOR
MUCH OF THE REGION SATURDAY INTO SATURDAY NIGHT...THOUGH PERIODS
OF SUNSHINE ARE LIKELY THROUGHOUT THE CENTRAL RIDGE AND VALLEY
REGION...AND SUSQUEHANNA RIVER VALLEY.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS OVER THE LOWER/THIN STRATO CU
CLOUD DECK PRESENT ACROSS THE REGION SATURDAY. ALL 12Z OPERATIONAL
MODEL DATA CONTINUES TO SUPPORT A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS NEAR 30 ACROSS THE MTNS...AND MID TO UPPER 30S IN
THE SE.

MOSTLY CLOUDY SKIES WITH LIGHT WIND SAT NIGHT WILL YIELD LOWS IN
THE LOWER 20S ACROSS THE MTNS...AND GENERALLY THE MID 20S
ELSEWHERE.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGH PRES WILL PROVIDE TRANQUIL WEATHER ON SUNDAY...WITH PARTLY TO
MOSTLY SUNNY SKIES AND SEASONABLE TEMPS. AFTER THAT...THE WEATHER
WILL BECOME INCREASINGLY UNSETTLED AS NEXT WEEK PROGRESSES.

CLOUDS WILL INCR SUNDAY NIGHT INTO MONDAY...AS HIGH PRES LOSES
ITS GRIP AND A WEAK AREA OF LOW PRES ORGANIZES OVER THE SERN UNITED
STATES. LIGHT PRECIP WILL WORK NWD INTO PENNSYLVANIA LATE MONDAY
INTO MONDAY NIGHT AND CONTINUE INTO TUES. INITIALLY...CONDS WILL
BE COLD ENOUGH FOR THE POSSIBILITY OF SOME WINTRY PRECIP.
HOWEVER...WARMER AIR WILL MAKE ITS WAY NWD LATER MONDAY NIGHT INTO
TUES AND GRADUALLY CHANGE ANY LINGERING PRECIP OVER TO PLAIN RAIN.

A MORE SIGNIFICANT STORM SYSTEM WILL GET ORGANIZED OVER THE
MISSISSIPPI VALLEY TUES NIGHT BEFORE PUSHING NWD INTO THE GREAT
LAKES ON WED. THIS SYSTEM WILL DRAW EVEN MILDER AIR NWD INTO THE
REGION...AND PROVIDE A RAINY AND BREEZY CHRISTMAS EVE DAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS FROM WEST TO EAST ACROSS PA IS POSSIBLE LATE WED/WED
NIGHT. SCT SNOW SHOWERS WILL CONTINUE INTO THURS ACROSS MAINLY
NRN AND WRN PA.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
OPERATIONAL MODELS AND THE GEFS SHOWING 850HPA TEMPS ALREADY
BEGINNING TO RISE NEXT FRI.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
LLVL NWRLY FLOW AND OROGRAPHIC FORCING OF A SHALLOW MOIST LAYER
WILL CONTINUE TO PRODUCE PLENTY OF CLOUDS ACROSS THE NW 1/2 TO
2/3RDS OF THE STATE WITH MAINLY MVFR BKN-OVC CIGS THROUGH
TONIGHT. KJST AND KBFD MAY TEETER ON THE UPPER END OF IFR FOR A
FEW HOURS LATER TONIGHT /AFTER 06Z/. IN CONTRAST...THE SE PENN
AIRFIELDS SUCH AS KMDT...KTHV AND KLNS WILL SEE MAINLY VFR...WITH
SKY CONDITIONS VARYING SCT-BKN030-040.

NORTHWEST WINDS OF 10-15 KTS WITH HIGHER GUSTS WILL DECREASE TO 8
KTS OR LESS LATER TONIGHT AND SATURDAY.

HIGH PRESSURE BUILDS EAST ACROSS PENN SATURDAY...WITH BKN-OVC CIGS
VARYING BETWEEN MVFR OVER THE HIGHER TERRAIN OF THE NORTH AND
WEST...TO SCT-BKN VFR IN THE VALLEYS.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...EVANEGO
AVIATION...LAMBERT/CERU



000
FXUS61 KCTP 200000
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
700 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER THE WESTERN GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND...BRINGING DRY WEATHER WITH
LIGHTER WIND. A DEEP UPPER TROUGH AND ASSOCIATED SFC LOW WILL LIFT
NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE OF NEXT WEEK
LIKELY BRINGING US RAIN AND WIND FOR CHRISTMAS EVE...THEN BLUSTERY
AND COLDER CONDITIONS FOR CHRISTMAS DAY WITH SCATTERED SNOW
SHOWERS.

&&

.NEAR TERM /UNTIL 7 AM SATURDAY MORNING/...
7 PM UPDATE...
BIG BREAKS IN CLOUDS LOCALLY. NRLY FLOW IS SHOVING THE CLOUDS DOWN
INTO THE POCONOS AND TRYING TO GET THEM INTO LEB/LANC COS. AT THIS
POINT...WILL CONTINUE TO COUNT ON THE DOWNSLOPE TO KEEP IT FROM
GOING TOTALLY OVC...BUT SOME INCREASE IN CLOUDS OVER THE NEXT FEW
HRS IN THE SE IS PROBABLY A GOOD CALL. OTHERWISE...THE SUBSIDENCE
IN BETWEEN THE NERN AND SERN PARTS OF THE STATE MAY CONTINUE TO
OPEN UP BIGGER BREAKS. WILL HAVE TO TWEAK NWRN MIN TEMPS AS THEY
ARE EXTREMELY CLOSE TO GOING MINS ATTM. ELSEWHERE...DEWPOINTS AND
ONLY SLOW DECREASE IN COVG LOOK LIKE THE MINS ARE OKAY FOR NOW.

PREV...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK TRAPPED BELOW A
MODERATELY STRONG SUBSIDENCE INVERSION /BASED AT AROUND 2-3KFT
AGL/ WILL PERSIST ACROSS MUCH OF NORTHERN AND WESTERN PENNSYLVANIA
LATE TODAY INTO SATURDAY...WHILE PARTIAL CLEARING OCCURS ACROSS
THE LOWER SUSQ VALLEY AND SURROUNDING AREAS.

TEMPS WILL REMAIN STEADY THROUGH LATE THIS AFTERNOON UNDER THE
10-15 KT NWRLY FLOW. READINGS WILL VARY FROM THE MID TO UPPER 20S
ACROSS THE NORTHERN AND WESTERN MOUNTAINS...TO THE LOWER 40S IN
THE SOUTHEAST.

A WEAK SFC RIDGE WILL MOVE TO NEAR THE PENN/OHIO BORDER BY 12Z
SATURDAY...BUT THE WEAK WESTERLY ISENTROPIC LIFT ALONG THE 285K
THETA SFC...AND SOME SHALLOW MOISTURE BEING ADVECTED SWD INTO THE
NRN MTNS OF PENN FROM LAKE ONTARIO...WILL MAINTAIN MOSTLY CLOUDY
TO CLOUDY SKIES. LITTLE MORE THAN A FEW FLURRIES OR SPOTTY -FZDZ
WILL FALL FROM THIS THIN CLOUD LAYER ACROSS THE HIGHER TERRAIN OF
THE LAURELS AND INVOF KBFD.

AFTER A PTLY CLOUDY LATE AFTERNOON AND EVENING IN THE SE PART OF
THE CWA...A BKN LAYER OF STRATO CU IS EXPECTED TO DRIFT SE /OR
FORM/ ACROSS THE REGION OVERNIGHT.

DUE TO THE NW-SE GRADIENT OF DECREASING CLOUDS...LOW TEMPS AT
DAYBREAK SAT WILL BE IN A RATHER TIGHT RANGE...FROM THE UPPER
TEENS TO LOWER 20S ACROSS THE MOUNTAINS...TO THE LOWER 20S IN THE
SE

&&

.SHORT TERM /7 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
A RIDGE OF HIGH PRESSURE...LIGHTER WIND...AND ASSOC DRIER AIR
MASS WILL BUILD EAST ACROSS THE STATE SATURDAY...PROVIDING THE
AREA WITH FAIR WEATHER.

HIGH RES MODEL DATA CONTINUES TO PAINT A MOSTLY CLOUDY PICTURE FOR
MUCH OF THE REGION SATURDAY INTO SATURDAY NIGHT...THOUGH PERIODS
OF SUNSHINE ARE LIKELY THROUGHOUT THE CENTRAL RIDGE AND VALLEY
REGION...AND SUSQUEHANNA RIVER VALLEY.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS OVER THE LOWER/THIN STRATO CU
CLOUD DECK PRESENT ACROSS THE REGION SATURDAY. ALL 12Z OPERATIONAL
MODEL DATA CONTINUES TO SUPPORT A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS NEAR 30 ACROSS THE MTNS...AND MID TO UPPER 30S IN
THE SE.

MOSTLY CLOUDY SKIES WITH LIGHT WIND SAT NIGHT WILL YIELD LOWS IN
THE LOWER 20S ACROSS THE MTNS...AND GENERALLY THE MID 20S
ELSEWHERE.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGH PRES WILL PROVIDE TRANQUIL WEATHER ON SUNDAY...WITH PARTLY TO
MOSTLY SUNNY SKIES AND SEASONABLE TEMPS. AFTER THAT...THE WEATHER
WILL BECOME INCREASINGLY UNSETTLED AS NEXT WEEK PROGRESSES.

CLOUDS WILL INCR SUNDAY NIGHT INTO MONDAY...AS HIGH PRES LOSES
ITS GRIP AND A WEAK AREA OF LOW PRES ORGANIZES OVER THE SERN UNITED
STATES. LIGHT PRECIP WILL WORK NWD INTO PENNSYLVANIA LATE MONDAY
INTO MONDAY NIGHT AND CONTINUE INTO TUES. INITIALLY...CONDS WILL
BE COLD ENOUGH FOR THE POSSIBILITY OF SOME WINTRY PRECIP.
HOWEVER...WARMER AIR WILL MAKE ITS WAY NWD LATER MONDAY NIGHT INTO
TUES AND GRADUALLY CHANGE ANY LINGERING PRECIP OVER TO PLAIN RAIN.

A MORE SIGNIFICANT STORM SYSTEM WILL GET ORGANIZED OVER THE
MISSISSIPPI VALLEY TUES NIGHT BEFORE PUSHING NWD INTO THE GREAT
LAKES ON WED. THIS SYSTEM WILL DRAW EVEN MILDER AIR NWD INTO THE
REGION...AND PROVIDE A RAINY AND BREEZY CHRISTMAS EVE DAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS FROM WEST TO EAST ACROSS PA IS POSSIBLE LATE WED/WED
NIGHT. SCT SNOW SHOWERS WILL CONTINUE INTO THURS ACROSS MAINLY
NRN AND WRN PA.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
OPERATIONAL MODELS AND THE GEFS SHOWING 850HPA TEMPS ALREADY
BEGINNING TO RISE NEXT FRI.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
LLVL NWRLY FLOW AND OROGRAPHIC FORCING OF A SHALLOW MOIST LAYER
WILL CONTINUE TO PRODUCE PLENTY OF CLOUDS ACROSS THE NW 1/2 TO
2/3RDS OF THE STATE WITH MAINLY MVFR BKN-OVC CIGS THROUGH
TONIGHT. KJST AND KBFD MAY TEETER ON THE UPPER END OF IFR FOR A
FEW HOURS LATER TONIGHT /AFTER 06Z/. IN CONTRAST...THE SE PENN
AIRFIELDS SUCH AS KMDT...KTHV AND KLNS WILL SEE MAINLY VFR...WITH
SKY CONDITIONS VARYING SCT-BKN030-040.

NORTHWEST WINDS OF 10-15 KTS WITH HIGHER GUSTS WILL DECREASE TO 8
KTS OR LESS LATER TONIGHT AND SATURDAY.

HIGH PRESSURE BUILDS EAST ACROSS PENN SATURDAY...WITH BKN-OVC CIGS
VARYING BETWEEN MVFR OVER THE HIGHER TERRAIN OF THE NORTH AND
WEST...TO SCT-BKN VFR IN THE VALLEYS.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...EVANEGO
AVIATION...LAMBERT/CERU




000
FXUS61 KCTP 192342
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
642 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER THE WESTERN GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND...BRINGING DRY WEATHER WITH
LIGHTER WIND. A DEEP UPPER TROUGH AND ASSOCIATED SFC LOW WILL LIFT
NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE OF NEXT WEEK
LIKELY BRINGING US RAIN AND WIND FOR CHRISTMAS EVE...THEN BLUSTERY
AND COLDER CONDITIONS FOR CHRISTMAS DAY WITH SCATTERED SNOW
SHOWERS.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK TRAPPED BELOW A
MODERATELY STRONG SUBSIDENCE INVERSION /BASED AT AROUND 2-3KFT
AGL/ WILL PERSIST ACROSS MUCH OF NORTHERN AND WESTERN PENNSYLVANIA
LATE TODAY INTO SATURDAY...WHILE PARTIAL CLEARING OCCURS ACROSS
THE LOWER SUSQ VALLEY AND SURROUNDING AREAS.

TEMPS WILL REMAIN STEADY THROUGH LATE THIS AFTERNOON UNDER THE
10-15 KT NWRLY FLOW. READINGS WILL VARY FROM THE MID TO UPPER 20S
ACROSS THE NORTHERN AND WESTERN MOUNTAINS...TO THE LOWER 40S IN
THE SOUTHEAST.

A WEAK SFC RIDGE WILL MOVE TO NEAR THE PENN/OHIO BORDER BY 12Z
SATURDAY...BUT THE WEAK WESTERLY ISENTROPIC LIFT ALONG THE 285K
THETA SFC...AND SOME SHALLOW MOISTURE BEING ADVECTED SWD INTO THE
NRN MTNS OF PENN FROM LAKE ONTARIO...WILL MAINTAIN MOSTLY CLOUDY
TO CLOUDY SKIES. LITTLE MORE THAN A FEW FLURRIES OR SPOTTY -FZDZ
WILL FALL FROM THIS THIN CLOUD LAYER ACROSS THE HIGHER TERRAIN OF
THE LAURELS AND INVOF KBFD.

AFTER A PTLY CLOUDY LATE AFTERNOON AND EVENING IN THE SE PART OF
THE CWA...A BKN LAYER OF STRATO CU IS EXPECTED TO DRIFT SE /OR
FORM/ ACROSS THE REGION OVERNIGHT.

DUE TO THE NW-SE GRADIENT OF DECREASING CLOUDS...LOW TEMPS AT
DAYBREAK SAT WILL BE IN A RATHER TIGHT RANGE...FROM THE UPPER
TEENS TO LOWER 20S ACROSS THE MOUNTAINS...TO THE LOWER 20S IN THE
SE

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
A RIDGE OF HIGH PRESSURE...LIGHTER WIND...AND ASSOC DRIER AIR
MASS WILL BUILD EAST ACROSS THE STATE SATURDAY...PROVIDING THE
AREA WITH FAIR WEATHER.

HIGH RES MODEL DATA CONTINUES TO PAINT A MOSTLY CLOUDY PICTURE FOR
MUCH OF THE REGION SATURDAY INTO SATURDAY NIGHT...THOUGH PERIODS
OF SUNSHINE ARE LIKELY THROUGHOUT THE CENTRAL RIDGE AND VALLEY
REGION...AND SUSQUEHANNA RIVER VALLEY.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS OVER THE LOWER/THIN STRATO CU
CLOUD DECK PRESENT ACROSS THE REGION SATURDAY. ALL 12Z OPERATIONAL
MODEL DATA CONTINUES TO SUPPORT A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS NEAR 30 ACROSS THE MTNS...AND MID TO UPPER 30S IN
THE SE.

MOSTLY CLOUDY SKIES WITH LIGHT WIND SAT NIGHT WILL YIELD LOWS IN
THE LOWER 20S ACROSS THE MTNS...AND GENERALLY THE MID 20S
ELSEWHERE.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGH PRES WILL PROVIDE TRANQUIL WEATHER ON SUNDAY...WITH PARTLY TO
MOSTLY SUNNY SKIES AND SEASONABLE TEMPS. AFTER THAT...THE WEATHER
WILL BECOME INCREASINGLY UNSETTLED AS NEXT WEEK PROGRESSES.

CLOUDS WILL INCR SUNDAY NIGHT INTO MONDAY...AS HIGH PRES LOSES
ITS GRIP AND A WEAK AREA OF LOW PRES ORGANIZES OVER THE SERN UNITED
STATES. LIGHT PRECIP WILL WORK NWD INTO PENNSYLVANIA LATE MONDAY
INTO MONDAY NIGHT AND CONTINUE INTO TUES. INITIALLY...CONDS WILL
BE COLD ENOUGH FOR THE POSSIBILITY OF SOME WINTRY PRECIP.
HOWEVER...WARMER AIR WILL MAKE ITS WAY NWD LATER MONDAY NIGHT INTO
TUES AND GRADUALLY CHANGE ANY LINGERING PRECIP OVER TO PLAIN RAIN.

A MORE SIGNIFICANT STORM SYSTEM WILL GET ORGANIZED OVER THE
MISSISSIPPI VALLEY TUES NIGHT BEFORE PUSHING NWD INTO THE GREAT
LAKES ON WED. THIS SYSTEM WILL DRAW EVEN MILDER AIR NWD INTO THE
REGION...AND PROVIDE A RAINY AND BREEZY CHRISTMAS EVE DAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS FROM WEST TO EAST ACROSS PA IS POSSIBLE LATE WED/WED
NIGHT. SCT SNOW SHOWERS WILL CONTINUE INTO THURS ACROSS MAINLY
NRN AND WRN PA.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
OPERATIONAL MODELS AND THE GEFS SHOWING 850HPA TEMPS ALREADY
BEGINNING TO RISE NEXT FRI.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
LLVL NWRLY FLOW AND OROGRAPHIC FORCING OF A SHALLOW MOIST LAYER
WILL CONTINUE TO PRODUCE PLENTY OF CLOUDS ACROSS THE NW 1/2 TO
2/3RDS OF THE STATE WITH MAINLY MVFR BKN-OVC CIGS THROUGH
TONIGHT. KJST AND KBFD MAY TEETER ON THE UPPER END OF IFR FOR A
FEW HOURS LATER TONIGHT /AFTER 06Z/. IN CONTRAST...THE SE PENN
AIRFIELDS SUCH AS KMDT...KTHV AND KLNS WILL SEE MAINLY VFR...WITH
SKY CONDITIONS VARYING SCT-BKN030-040.

NORTHWEST WINDS OF 10-15 KTS WITH HIGHER GUSTS WILL DECREASE TO 8
KTS OR LESS LATER TONIGHT AND SATURDAY.

HIGH PRESSURE BUILDS EAST ACROSS PENN SATURDAY...WITH BKN-OVC CIGS
VARYING BETWEEN MVFR OVER THE HIGHER TERRAIN OF THE NORTH AND
WEST...TO SCT-BKN VFR IN THE VALLEYS.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...EVANEGO
AVIATION...LAMBERT/CERU




000
FXUS61 KCTP 192342
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
642 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER THE WESTERN GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND...BRINGING DRY WEATHER WITH
LIGHTER WIND. A DEEP UPPER TROUGH AND ASSOCIATED SFC LOW WILL LIFT
NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE OF NEXT WEEK
LIKELY BRINGING US RAIN AND WIND FOR CHRISTMAS EVE...THEN BLUSTERY
AND COLDER CONDITIONS FOR CHRISTMAS DAY WITH SCATTERED SNOW
SHOWERS.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK TRAPPED BELOW A
MODERATELY STRONG SUBSIDENCE INVERSION /BASED AT AROUND 2-3KFT
AGL/ WILL PERSIST ACROSS MUCH OF NORTHERN AND WESTERN PENNSYLVANIA
LATE TODAY INTO SATURDAY...WHILE PARTIAL CLEARING OCCURS ACROSS
THE LOWER SUSQ VALLEY AND SURROUNDING AREAS.

TEMPS WILL REMAIN STEADY THROUGH LATE THIS AFTERNOON UNDER THE
10-15 KT NWRLY FLOW. READINGS WILL VARY FROM THE MID TO UPPER 20S
ACROSS THE NORTHERN AND WESTERN MOUNTAINS...TO THE LOWER 40S IN
THE SOUTHEAST.

A WEAK SFC RIDGE WILL MOVE TO NEAR THE PENN/OHIO BORDER BY 12Z
SATURDAY...BUT THE WEAK WESTERLY ISENTROPIC LIFT ALONG THE 285K
THETA SFC...AND SOME SHALLOW MOISTURE BEING ADVECTED SWD INTO THE
NRN MTNS OF PENN FROM LAKE ONTARIO...WILL MAINTAIN MOSTLY CLOUDY
TO CLOUDY SKIES. LITTLE MORE THAN A FEW FLURRIES OR SPOTTY -FZDZ
WILL FALL FROM THIS THIN CLOUD LAYER ACROSS THE HIGHER TERRAIN OF
THE LAURELS AND INVOF KBFD.

AFTER A PTLY CLOUDY LATE AFTERNOON AND EVENING IN THE SE PART OF
THE CWA...A BKN LAYER OF STRATO CU IS EXPECTED TO DRIFT SE /OR
FORM/ ACROSS THE REGION OVERNIGHT.

DUE TO THE NW-SE GRADIENT OF DECREASING CLOUDS...LOW TEMPS AT
DAYBREAK SAT WILL BE IN A RATHER TIGHT RANGE...FROM THE UPPER
TEENS TO LOWER 20S ACROSS THE MOUNTAINS...TO THE LOWER 20S IN THE
SE

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
A RIDGE OF HIGH PRESSURE...LIGHTER WIND...AND ASSOC DRIER AIR
MASS WILL BUILD EAST ACROSS THE STATE SATURDAY...PROVIDING THE
AREA WITH FAIR WEATHER.

HIGH RES MODEL DATA CONTINUES TO PAINT A MOSTLY CLOUDY PICTURE FOR
MUCH OF THE REGION SATURDAY INTO SATURDAY NIGHT...THOUGH PERIODS
OF SUNSHINE ARE LIKELY THROUGHOUT THE CENTRAL RIDGE AND VALLEY
REGION...AND SUSQUEHANNA RIVER VALLEY.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS OVER THE LOWER/THIN STRATO CU
CLOUD DECK PRESENT ACROSS THE REGION SATURDAY. ALL 12Z OPERATIONAL
MODEL DATA CONTINUES TO SUPPORT A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS NEAR 30 ACROSS THE MTNS...AND MID TO UPPER 30S IN
THE SE.

MOSTLY CLOUDY SKIES WITH LIGHT WIND SAT NIGHT WILL YIELD LOWS IN
THE LOWER 20S ACROSS THE MTNS...AND GENERALLY THE MID 20S
ELSEWHERE.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGH PRES WILL PROVIDE TRANQUIL WEATHER ON SUNDAY...WITH PARTLY TO
MOSTLY SUNNY SKIES AND SEASONABLE TEMPS. AFTER THAT...THE WEATHER
WILL BECOME INCREASINGLY UNSETTLED AS NEXT WEEK PROGRESSES.

CLOUDS WILL INCR SUNDAY NIGHT INTO MONDAY...AS HIGH PRES LOSES
ITS GRIP AND A WEAK AREA OF LOW PRES ORGANIZES OVER THE SERN UNITED
STATES. LIGHT PRECIP WILL WORK NWD INTO PENNSYLVANIA LATE MONDAY
INTO MONDAY NIGHT AND CONTINUE INTO TUES. INITIALLY...CONDS WILL
BE COLD ENOUGH FOR THE POSSIBILITY OF SOME WINTRY PRECIP.
HOWEVER...WARMER AIR WILL MAKE ITS WAY NWD LATER MONDAY NIGHT INTO
TUES AND GRADUALLY CHANGE ANY LINGERING PRECIP OVER TO PLAIN RAIN.

A MORE SIGNIFICANT STORM SYSTEM WILL GET ORGANIZED OVER THE
MISSISSIPPI VALLEY TUES NIGHT BEFORE PUSHING NWD INTO THE GREAT
LAKES ON WED. THIS SYSTEM WILL DRAW EVEN MILDER AIR NWD INTO THE
REGION...AND PROVIDE A RAINY AND BREEZY CHRISTMAS EVE DAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS FROM WEST TO EAST ACROSS PA IS POSSIBLE LATE WED/WED
NIGHT. SCT SNOW SHOWERS WILL CONTINUE INTO THURS ACROSS MAINLY
NRN AND WRN PA.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
OPERATIONAL MODELS AND THE GEFS SHOWING 850HPA TEMPS ALREADY
BEGINNING TO RISE NEXT FRI.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
LLVL NWRLY FLOW AND OROGRAPHIC FORCING OF A SHALLOW MOIST LAYER
WILL CONTINUE TO PRODUCE PLENTY OF CLOUDS ACROSS THE NW 1/2 TO
2/3RDS OF THE STATE WITH MAINLY MVFR BKN-OVC CIGS THROUGH
TONIGHT. KJST AND KBFD MAY TEETER ON THE UPPER END OF IFR FOR A
FEW HOURS LATER TONIGHT /AFTER 06Z/. IN CONTRAST...THE SE PENN
AIRFIELDS SUCH AS KMDT...KTHV AND KLNS WILL SEE MAINLY VFR...WITH
SKY CONDITIONS VARYING SCT-BKN030-040.

NORTHWEST WINDS OF 10-15 KTS WITH HIGHER GUSTS WILL DECREASE TO 8
KTS OR LESS LATER TONIGHT AND SATURDAY.

HIGH PRESSURE BUILDS EAST ACROSS PENN SATURDAY...WITH BKN-OVC CIGS
VARYING BETWEEN MVFR OVER THE HIGHER TERRAIN OF THE NORTH AND
WEST...TO SCT-BKN VFR IN THE VALLEYS.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...EVANEGO
AVIATION...LAMBERT/CERU




000
FXUS61 KCTP 192342
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
642 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER THE WESTERN GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND...BRINGING DRY WEATHER WITH
LIGHTER WIND. A DEEP UPPER TROUGH AND ASSOCIATED SFC LOW WILL LIFT
NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE OF NEXT WEEK
LIKELY BRINGING US RAIN AND WIND FOR CHRISTMAS EVE...THEN BLUSTERY
AND COLDER CONDITIONS FOR CHRISTMAS DAY WITH SCATTERED SNOW
SHOWERS.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK TRAPPED BELOW A
MODERATELY STRONG SUBSIDENCE INVERSION /BASED AT AROUND 2-3KFT
AGL/ WILL PERSIST ACROSS MUCH OF NORTHERN AND WESTERN PENNSYLVANIA
LATE TODAY INTO SATURDAY...WHILE PARTIAL CLEARING OCCURS ACROSS
THE LOWER SUSQ VALLEY AND SURROUNDING AREAS.

TEMPS WILL REMAIN STEADY THROUGH LATE THIS AFTERNOON UNDER THE
10-15 KT NWRLY FLOW. READINGS WILL VARY FROM THE MID TO UPPER 20S
ACROSS THE NORTHERN AND WESTERN MOUNTAINS...TO THE LOWER 40S IN
THE SOUTHEAST.

A WEAK SFC RIDGE WILL MOVE TO NEAR THE PENN/OHIO BORDER BY 12Z
SATURDAY...BUT THE WEAK WESTERLY ISENTROPIC LIFT ALONG THE 285K
THETA SFC...AND SOME SHALLOW MOISTURE BEING ADVECTED SWD INTO THE
NRN MTNS OF PENN FROM LAKE ONTARIO...WILL MAINTAIN MOSTLY CLOUDY
TO CLOUDY SKIES. LITTLE MORE THAN A FEW FLURRIES OR SPOTTY -FZDZ
WILL FALL FROM THIS THIN CLOUD LAYER ACROSS THE HIGHER TERRAIN OF
THE LAURELS AND INVOF KBFD.

AFTER A PTLY CLOUDY LATE AFTERNOON AND EVENING IN THE SE PART OF
THE CWA...A BKN LAYER OF STRATO CU IS EXPECTED TO DRIFT SE /OR
FORM/ ACROSS THE REGION OVERNIGHT.

DUE TO THE NW-SE GRADIENT OF DECREASING CLOUDS...LOW TEMPS AT
DAYBREAK SAT WILL BE IN A RATHER TIGHT RANGE...FROM THE UPPER
TEENS TO LOWER 20S ACROSS THE MOUNTAINS...TO THE LOWER 20S IN THE
SE

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
A RIDGE OF HIGH PRESSURE...LIGHTER WIND...AND ASSOC DRIER AIR
MASS WILL BUILD EAST ACROSS THE STATE SATURDAY...PROVIDING THE
AREA WITH FAIR WEATHER.

HIGH RES MODEL DATA CONTINUES TO PAINT A MOSTLY CLOUDY PICTURE FOR
MUCH OF THE REGION SATURDAY INTO SATURDAY NIGHT...THOUGH PERIODS
OF SUNSHINE ARE LIKELY THROUGHOUT THE CENTRAL RIDGE AND VALLEY
REGION...AND SUSQUEHANNA RIVER VALLEY.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS OVER THE LOWER/THIN STRATO CU
CLOUD DECK PRESENT ACROSS THE REGION SATURDAY. ALL 12Z OPERATIONAL
MODEL DATA CONTINUES TO SUPPORT A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS NEAR 30 ACROSS THE MTNS...AND MID TO UPPER 30S IN
THE SE.

MOSTLY CLOUDY SKIES WITH LIGHT WIND SAT NIGHT WILL YIELD LOWS IN
THE LOWER 20S ACROSS THE MTNS...AND GENERALLY THE MID 20S
ELSEWHERE.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGH PRES WILL PROVIDE TRANQUIL WEATHER ON SUNDAY...WITH PARTLY TO
MOSTLY SUNNY SKIES AND SEASONABLE TEMPS. AFTER THAT...THE WEATHER
WILL BECOME INCREASINGLY UNSETTLED AS NEXT WEEK PROGRESSES.

CLOUDS WILL INCR SUNDAY NIGHT INTO MONDAY...AS HIGH PRES LOSES
ITS GRIP AND A WEAK AREA OF LOW PRES ORGANIZES OVER THE SERN UNITED
STATES. LIGHT PRECIP WILL WORK NWD INTO PENNSYLVANIA LATE MONDAY
INTO MONDAY NIGHT AND CONTINUE INTO TUES. INITIALLY...CONDS WILL
BE COLD ENOUGH FOR THE POSSIBILITY OF SOME WINTRY PRECIP.
HOWEVER...WARMER AIR WILL MAKE ITS WAY NWD LATER MONDAY NIGHT INTO
TUES AND GRADUALLY CHANGE ANY LINGERING PRECIP OVER TO PLAIN RAIN.

A MORE SIGNIFICANT STORM SYSTEM WILL GET ORGANIZED OVER THE
MISSISSIPPI VALLEY TUES NIGHT BEFORE PUSHING NWD INTO THE GREAT
LAKES ON WED. THIS SYSTEM WILL DRAW EVEN MILDER AIR NWD INTO THE
REGION...AND PROVIDE A RAINY AND BREEZY CHRISTMAS EVE DAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS FROM WEST TO EAST ACROSS PA IS POSSIBLE LATE WED/WED
NIGHT. SCT SNOW SHOWERS WILL CONTINUE INTO THURS ACROSS MAINLY
NRN AND WRN PA.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
OPERATIONAL MODELS AND THE GEFS SHOWING 850HPA TEMPS ALREADY
BEGINNING TO RISE NEXT FRI.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
LLVL NWRLY FLOW AND OROGRAPHIC FORCING OF A SHALLOW MOIST LAYER
WILL CONTINUE TO PRODUCE PLENTY OF CLOUDS ACROSS THE NW 1/2 TO
2/3RDS OF THE STATE WITH MAINLY MVFR BKN-OVC CIGS THROUGH
TONIGHT. KJST AND KBFD MAY TEETER ON THE UPPER END OF IFR FOR A
FEW HOURS LATER TONIGHT /AFTER 06Z/. IN CONTRAST...THE SE PENN
AIRFIELDS SUCH AS KMDT...KTHV AND KLNS WILL SEE MAINLY VFR...WITH
SKY CONDITIONS VARYING SCT-BKN030-040.

NORTHWEST WINDS OF 10-15 KTS WITH HIGHER GUSTS WILL DECREASE TO 8
KTS OR LESS LATER TONIGHT AND SATURDAY.

HIGH PRESSURE BUILDS EAST ACROSS PENN SATURDAY...WITH BKN-OVC CIGS
VARYING BETWEEN MVFR OVER THE HIGHER TERRAIN OF THE NORTH AND
WEST...TO SCT-BKN VFR IN THE VALLEYS.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...EVANEGO
AVIATION...LAMBERT/CERU




000
FXUS61 KCTP 192342
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
642 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER THE WESTERN GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND...BRINGING DRY WEATHER WITH
LIGHTER WIND. A DEEP UPPER TROUGH AND ASSOCIATED SFC LOW WILL LIFT
NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE OF NEXT WEEK
LIKELY BRINGING US RAIN AND WIND FOR CHRISTMAS EVE...THEN BLUSTERY
AND COLDER CONDITIONS FOR CHRISTMAS DAY WITH SCATTERED SNOW
SHOWERS.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK TRAPPED BELOW A
MODERATELY STRONG SUBSIDENCE INVERSION /BASED AT AROUND 2-3KFT
AGL/ WILL PERSIST ACROSS MUCH OF NORTHERN AND WESTERN PENNSYLVANIA
LATE TODAY INTO SATURDAY...WHILE PARTIAL CLEARING OCCURS ACROSS
THE LOWER SUSQ VALLEY AND SURROUNDING AREAS.

TEMPS WILL REMAIN STEADY THROUGH LATE THIS AFTERNOON UNDER THE
10-15 KT NWRLY FLOW. READINGS WILL VARY FROM THE MID TO UPPER 20S
ACROSS THE NORTHERN AND WESTERN MOUNTAINS...TO THE LOWER 40S IN
THE SOUTHEAST.

A WEAK SFC RIDGE WILL MOVE TO NEAR THE PENN/OHIO BORDER BY 12Z
SATURDAY...BUT THE WEAK WESTERLY ISENTROPIC LIFT ALONG THE 285K
THETA SFC...AND SOME SHALLOW MOISTURE BEING ADVECTED SWD INTO THE
NRN MTNS OF PENN FROM LAKE ONTARIO...WILL MAINTAIN MOSTLY CLOUDY
TO CLOUDY SKIES. LITTLE MORE THAN A FEW FLURRIES OR SPOTTY -FZDZ
WILL FALL FROM THIS THIN CLOUD LAYER ACROSS THE HIGHER TERRAIN OF
THE LAURELS AND INVOF KBFD.

AFTER A PTLY CLOUDY LATE AFTERNOON AND EVENING IN THE SE PART OF
THE CWA...A BKN LAYER OF STRATO CU IS EXPECTED TO DRIFT SE /OR
FORM/ ACROSS THE REGION OVERNIGHT.

DUE TO THE NW-SE GRADIENT OF DECREASING CLOUDS...LOW TEMPS AT
DAYBREAK SAT WILL BE IN A RATHER TIGHT RANGE...FROM THE UPPER
TEENS TO LOWER 20S ACROSS THE MOUNTAINS...TO THE LOWER 20S IN THE
SE

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
A RIDGE OF HIGH PRESSURE...LIGHTER WIND...AND ASSOC DRIER AIR
MASS WILL BUILD EAST ACROSS THE STATE SATURDAY...PROVIDING THE
AREA WITH FAIR WEATHER.

HIGH RES MODEL DATA CONTINUES TO PAINT A MOSTLY CLOUDY PICTURE FOR
MUCH OF THE REGION SATURDAY INTO SATURDAY NIGHT...THOUGH PERIODS
OF SUNSHINE ARE LIKELY THROUGHOUT THE CENTRAL RIDGE AND VALLEY
REGION...AND SUSQUEHANNA RIVER VALLEY.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS OVER THE LOWER/THIN STRATO CU
CLOUD DECK PRESENT ACROSS THE REGION SATURDAY. ALL 12Z OPERATIONAL
MODEL DATA CONTINUES TO SUPPORT A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS NEAR 30 ACROSS THE MTNS...AND MID TO UPPER 30S IN
THE SE.

MOSTLY CLOUDY SKIES WITH LIGHT WIND SAT NIGHT WILL YIELD LOWS IN
THE LOWER 20S ACROSS THE MTNS...AND GENERALLY THE MID 20S
ELSEWHERE.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGH PRES WILL PROVIDE TRANQUIL WEATHER ON SUNDAY...WITH PARTLY TO
MOSTLY SUNNY SKIES AND SEASONABLE TEMPS. AFTER THAT...THE WEATHER
WILL BECOME INCREASINGLY UNSETTLED AS NEXT WEEK PROGRESSES.

CLOUDS WILL INCR SUNDAY NIGHT INTO MONDAY...AS HIGH PRES LOSES
ITS GRIP AND A WEAK AREA OF LOW PRES ORGANIZES OVER THE SERN UNITED
STATES. LIGHT PRECIP WILL WORK NWD INTO PENNSYLVANIA LATE MONDAY
INTO MONDAY NIGHT AND CONTINUE INTO TUES. INITIALLY...CONDS WILL
BE COLD ENOUGH FOR THE POSSIBILITY OF SOME WINTRY PRECIP.
HOWEVER...WARMER AIR WILL MAKE ITS WAY NWD LATER MONDAY NIGHT INTO
TUES AND GRADUALLY CHANGE ANY LINGERING PRECIP OVER TO PLAIN RAIN.

A MORE SIGNIFICANT STORM SYSTEM WILL GET ORGANIZED OVER THE
MISSISSIPPI VALLEY TUES NIGHT BEFORE PUSHING NWD INTO THE GREAT
LAKES ON WED. THIS SYSTEM WILL DRAW EVEN MILDER AIR NWD INTO THE
REGION...AND PROVIDE A RAINY AND BREEZY CHRISTMAS EVE DAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS FROM WEST TO EAST ACROSS PA IS POSSIBLE LATE WED/WED
NIGHT. SCT SNOW SHOWERS WILL CONTINUE INTO THURS ACROSS MAINLY
NRN AND WRN PA.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
OPERATIONAL MODELS AND THE GEFS SHOWING 850HPA TEMPS ALREADY
BEGINNING TO RISE NEXT FRI.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
LLVL NWRLY FLOW AND OROGRAPHIC FORCING OF A SHALLOW MOIST LAYER
WILL CONTINUE TO PRODUCE PLENTY OF CLOUDS ACROSS THE NW 1/2 TO
2/3RDS OF THE STATE WITH MAINLY MVFR BKN-OVC CIGS THROUGH
TONIGHT. KJST AND KBFD MAY TEETER ON THE UPPER END OF IFR FOR A
FEW HOURS LATER TONIGHT /AFTER 06Z/. IN CONTRAST...THE SE PENN
AIRFIELDS SUCH AS KMDT...KTHV AND KLNS WILL SEE MAINLY VFR...WITH
SKY CONDITIONS VARYING SCT-BKN030-040.

NORTHWEST WINDS OF 10-15 KTS WITH HIGHER GUSTS WILL DECREASE TO 8
KTS OR LESS LATER TONIGHT AND SATURDAY.

HIGH PRESSURE BUILDS EAST ACROSS PENN SATURDAY...WITH BKN-OVC CIGS
VARYING BETWEEN MVFR OVER THE HIGHER TERRAIN OF THE NORTH AND
WEST...TO SCT-BKN VFR IN THE VALLEYS.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...EVANEGO
AVIATION...LAMBERT/CERU




000
FXUS61 KPHI 192328
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
628 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE JUST NORTH OF LAKE SUPERIOR WILL GRADUALLY MOVE
EASTWARD INTO NORTHERN NEW ENGLAND THRU MONDAY. A WAVE OF LOW
PRESSURE WILL FORM ALONG THE MID-ATLANTIC COASTLINE ON MONDAY
AND MOVE NORTHEASTWARD JUST OFFSHORE ON TUESDAY. MEANWHILE...
A STRONG AREA OF LOW-PRESSURE WILL FORM OVER THE MISSISSIPPI
VALLEY AND MOVE THRU THE GREAT LAKES REGION DURING THE MIDDLE
OF THE WEEK...BRINGING A STRONG COLD FRONT THRU THE REGION
BY THURSDAY. HIGH PRESSURE IS PROJECTED TO BUILD IN ON FRIDAY.

&&

.NEAR TERM /THROUGH SATURDAY/...
WITH THIS ESTF UPDATE WE ADJUSTED SKY COVER GOING MORE PESSIMISTIC
NORTH BASED ON CURRENT POSNING OF CLOUDS AND THE 18Z MODELS
BRINGING AN 850MB SHORT WAVE THRU THE NORTHERN PART OF OUR CWA. WE
UPPED TEMPS SLIGHTLY NORTH, LEFT THE REST AS IS. WITH LIGHT WINDS,
CONFIDENCE ABOUT TEMPS DUE TO CLOUD COVER UNCERTAINTY IS LOWER
THAN AVERAGE.

FOR TONIGHT...NW WINDS WILL CONTINUE BUT WILL BECOME LIGHTER AS
CANADIAN LOW PRES MOVES AWAY AND HIGH PRES MOVES CLOSED WITH
RESULTING RELAXED PRES GRAD.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH 6 PM SATURDAY/...
FOR SATURDAY...HIGH PRES CENTERED OVER CANADA SHIFTS EWD FROM
ONTARIO INTO QUEBEC. A RIDGE AXIS IS FCST TO EXTEND SWD THROUGH THE
MID-ATLANTIC REGION RESULTING IN ONLY LIGHT NLY WINDS. SOME LOW-LVL
MOISTURE SHOULD REMAIN TRAPPED BELOW THE LARGE-SCALE SUBSIDENCE
INVERSION BUT HARD TO SAY HOW EXTENSIVE ANY LOW CLOUDS MAY BE. THE
12-KM NAM SHOWS A THIN LOW CLOUD LAYER DEVELOPING DURG THE DAY BUT
HIGHER-RES ARW/NMM AND THE GFS DO NOT. THERE WILL BE SOME HIGHER
CLOUDS ALSO ASSOCD WITH THE SHRTWV NOW MOVING ENEWD OUT OF THE SRN
PLAINS...HWVR POPS REMAIN NEAR ZERO.

&&

.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
HIGHLIGHTS...

* SLIGHT CHANCE OF SNOW SHOWERS SUNDAY MORNING MAINLY NORTH.
* SNOW POSSIBLE NORTHWEST OF THE I-95 CORRIDOR LATE MONDAY
  THRU EARLY TUESDAY.
* POTENTIAL FOR HEAVY RAIN INCREASING ON CHRISTMAS EVE DAY.

OVERVIEW...

MID-LEVEL BLOCKING PATTERN OVER NOAM BEGINS TO DISLODGE IN RESPONSE
JET ENERGY MOVING INTO THE PACIFIC NORTHWEST THIS WEEKEND...CARVING
OUT A DEEP TROUGH OVER THE MS VALLEY EARLY EARLY NEXT WEEK...WHICH
LEADS TO INCLEMENT WEATHER IN THE TUESDAY THRU WEDNESDAY TIME FRAME.

DETAILS...

SUNDAY...
SHORTWAVE LIFTING THROUGH THE REGION EARLY IN THE DAY MAY GENERATE
ENOUGH LIFT ALONG WITH MARGINAL MOISTURE IN THE COLUMN TO PRODUCE
SOME LIGHT SNOW SHOWERS...MAINLY DURING THE PRE-DAWN HOURS. LITTLE
IF ANY ACCUMULATION EXPECTED AS MOISTURE IS VERY LIMITED. RIDGING
THEN BUILDS IN SO FAIR WEATHER IS EXPECTED THE REMAINDER OF THE DAY.

MONDAY AND TUESDAY...
HIGH PRESSURE ANCHORS ALONG THE LEE OF THE APPALACHIANS. A SOUTHERN
STREAM SHORTWAVE WILL INDUCE LOW-PRESSURE OF THE MID-ATLANTIC COAST.
MODELS BRING QPF NORTHWARD INTO THE AREA ON MONDAY NIGHT INTO EARLY
TUESDAY. THERMAL PROFILES ARE COLD ENOUGH FOR SNOW TO THE NORTHWEST
OF THE I-95 CORRIDOR...BUT THE BEST LIFT IS FOCUSED JUST SOUTHEAST
OF THIS AREA...AND THE SYSTEM COULD TRACK FURTHER TO THE SOUTH PER
12Z UKMET MODEL. STILL A LOT OF UNCERTAINTY WITH ULTIMATE TRACK.

WEDNESDAY...
A MID-LEVEL RIDGE WILL MOVE THROUGH THE REGION TUESDAY NIGHT INTO
EARLY WEDNESDAY LEADING TO A BRIEF RESPITE BETWEEN WEATHER SYSTEMS.
THEN A MID-LEVEL TROUGH IS PROJECTED TO BECOME NEGATIVELY TILTED
OVER THE OHIO VALLEY ON WED...LEADING TO A MERIDIONAL FLOW ALONG
THE EAST COAST...WITH THE ENTIRE COLUMN EXPECTED TO BE WELL ABOVE
FREEZING ACROSS THE CWA FAVORING A RAIN EVENT. THERE ARE SEVERAL
INGREDIENTS COMING TOGETHER FOR HEAVY RAIN. IN PARTICULAR...DEEP
GULF MOISTURE...LOW-LEVEL ISENTROPIC LIFT...MID-LEVEL PVA...AND
THE RIGHT-REAR QUADRANT OF A 140 KNOT UPPER-LEVEL JET JUST NORTH.
THE SYSTEM SHOULD BE FAIRLY PROGRESSIVE BUT WILL HAVE TO MONITOR
POTENTIAL FOR FLOODING.

THU AND FRI...
LOW-PRESSURE MOVES NORTHWARD INTO QUEBEC AND HIGH-PRESSURE BEGINS
TO BUILD IN. TEMPERATURES WILL RETURN TO SEASONABLE LEVELS AND
THERE COULD BE SNOW SHOWERS IN THE BLUSTERY NORTHWEST FLOW.

&&

.AVIATION /23Z FRIDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

THE 00Z TAFS TAKE CIGS DOWN TO MVFR LEVELS TONIGHT FROM THE KPHL
AREA AIRPORTS NORTHWESTWARD WITH IMPROVEMENT ON SATURDAY. ITS BEEN
TOUGH TO SHAKE THIS STRATOCU LEVEL CLOUDINESS PATTERN.

FOR TONIGHT. LOW CLOUDS ADVANCING IN FROM THE HIGHER TERRAIN
AIRPORTS ARE STILL HEADING INTO THE TERMINALS. WE BRING MVFR CIG
POTENTIAL FROM THE GET GO AT KABE AND KRDG (HIER CONFIDENCE
OVERNIGHT) AND BRING IT DOWN TO THE KPHL METRO AIRPORTS AFTER 05Z.
WE LEAVE KACY AND KMIV VFR. WINDS WILL BE LIGHT FROM THE
NORTHWEST. NO VSBY RESTRICTIONS EXPECTED.

ON SATURDAY, PREDICTING THE MVFR CIG TO BECOME SCATTERED DURING
THE MORNING FROM THE KPHL METRO AIRPORTS NWWD WITH A CIRRUS CIG
ABOVE. KACY AND KMIV NOT EXPECTING A MVFR CIG. IT WILL BE A WEAK
PRESSURE PATTERN AND WINDS WILL BE LIGHT. A NORTHERLY DIRECTION
IS FAVORED, BUT SPEEDS ARE EXPECTED TO REMAIN BELOW 10 KNOTS,
PROBABLY PREDOMINATELY LESS THAN 6 KNOTS AT SOME OF THE MORE
RURAL AIRPORTS AND TERMINALS.

OUTLOOK...
SATURDAY NIGHT AND SUNDAY...VFR CONDITIONS EXPECTED.
MONDAY AND TUESDAY...IFR POSSIBLE IN SHRA AND SHSN.
WEDNESDAY...IFR POSSIBLE IN RAIN AND FOG.

&&

.MARINE...
SUB-SCA CONDS ARE EXPECTED FOR THE NEXT 24 HOURS AT LEAST. SMWHT
GUST NW WINDS THIS EVENING WILL GRADUALLY DIMINISH TONIGHT THROUGH
SATURDAY AS A RIDGE OF HIGH PRES MOVES OVERHEAD. SEAS ARE
CURRENTLY RUNNING 2 TO 3 FT BUT THEY SHOULD GRADUALLY DIMINISH
ALSO.

OUTLOOK...
SUNDAY AND MONDAY...SUB-SCA CONDITIONS EXPECTED.
TUESDAY...SCA MAY BE NEEDED FOR BUILDING SEAS.
WEDNESDAY...GALE WARNING MAY BE NEEDED.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANCK
NEAR TERM...AMC/GIGI
SHORT TERM...AMC
LONG TERM...FRANCK
AVIATION...FRANCK/GIGI
MARINE...AMC/FRANCK







000
FXUS61 KPHI 192328
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
628 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE JUST NORTH OF LAKE SUPERIOR WILL GRADUALLY MOVE
EASTWARD INTO NORTHERN NEW ENGLAND THRU MONDAY. A WAVE OF LOW
PRESSURE WILL FORM ALONG THE MID-ATLANTIC COASTLINE ON MONDAY
AND MOVE NORTHEASTWARD JUST OFFSHORE ON TUESDAY. MEANWHILE...
A STRONG AREA OF LOW-PRESSURE WILL FORM OVER THE MISSISSIPPI
VALLEY AND MOVE THRU THE GREAT LAKES REGION DURING THE MIDDLE
OF THE WEEK...BRINGING A STRONG COLD FRONT THRU THE REGION
BY THURSDAY. HIGH PRESSURE IS PROJECTED TO BUILD IN ON FRIDAY.

&&

.NEAR TERM /THROUGH SATURDAY/...
WITH THIS ESTF UPDATE WE ADJUSTED SKY COVER GOING MORE PESSIMISTIC
NORTH BASED ON CURRENT POSNING OF CLOUDS AND THE 18Z MODELS
BRINGING AN 850MB SHORT WAVE THRU THE NORTHERN PART OF OUR CWA. WE
UPPED TEMPS SLIGHTLY NORTH, LEFT THE REST AS IS. WITH LIGHT WINDS,
CONFIDENCE ABOUT TEMPS DUE TO CLOUD COVER UNCERTAINTY IS LOWER
THAN AVERAGE.

FOR TONIGHT...NW WINDS WILL CONTINUE BUT WILL BECOME LIGHTER AS
CANADIAN LOW PRES MOVES AWAY AND HIGH PRES MOVES CLOSED WITH
RESULTING RELAXED PRES GRAD.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH 6 PM SATURDAY/...
FOR SATURDAY...HIGH PRES CENTERED OVER CANADA SHIFTS EWD FROM
ONTARIO INTO QUEBEC. A RIDGE AXIS IS FCST TO EXTEND SWD THROUGH THE
MID-ATLANTIC REGION RESULTING IN ONLY LIGHT NLY WINDS. SOME LOW-LVL
MOISTURE SHOULD REMAIN TRAPPED BELOW THE LARGE-SCALE SUBSIDENCE
INVERSION BUT HARD TO SAY HOW EXTENSIVE ANY LOW CLOUDS MAY BE. THE
12-KM NAM SHOWS A THIN LOW CLOUD LAYER DEVELOPING DURG THE DAY BUT
HIGHER-RES ARW/NMM AND THE GFS DO NOT. THERE WILL BE SOME HIGHER
CLOUDS ALSO ASSOCD WITH THE SHRTWV NOW MOVING ENEWD OUT OF THE SRN
PLAINS...HWVR POPS REMAIN NEAR ZERO.

&&

.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
HIGHLIGHTS...

* SLIGHT CHANCE OF SNOW SHOWERS SUNDAY MORNING MAINLY NORTH.
* SNOW POSSIBLE NORTHWEST OF THE I-95 CORRIDOR LATE MONDAY
  THRU EARLY TUESDAY.
* POTENTIAL FOR HEAVY RAIN INCREASING ON CHRISTMAS EVE DAY.

OVERVIEW...

MID-LEVEL BLOCKING PATTERN OVER NOAM BEGINS TO DISLODGE IN RESPONSE
JET ENERGY MOVING INTO THE PACIFIC NORTHWEST THIS WEEKEND...CARVING
OUT A DEEP TROUGH OVER THE MS VALLEY EARLY EARLY NEXT WEEK...WHICH
LEADS TO INCLEMENT WEATHER IN THE TUESDAY THRU WEDNESDAY TIME FRAME.

DETAILS...

SUNDAY...
SHORTWAVE LIFTING THROUGH THE REGION EARLY IN THE DAY MAY GENERATE
ENOUGH LIFT ALONG WITH MARGINAL MOISTURE IN THE COLUMN TO PRODUCE
SOME LIGHT SNOW SHOWERS...MAINLY DURING THE PRE-DAWN HOURS. LITTLE
IF ANY ACCUMULATION EXPECTED AS MOISTURE IS VERY LIMITED. RIDGING
THEN BUILDS IN SO FAIR WEATHER IS EXPECTED THE REMAINDER OF THE DAY.

MONDAY AND TUESDAY...
HIGH PRESSURE ANCHORS ALONG THE LEE OF THE APPALACHIANS. A SOUTHERN
STREAM SHORTWAVE WILL INDUCE LOW-PRESSURE OF THE MID-ATLANTIC COAST.
MODELS BRING QPF NORTHWARD INTO THE AREA ON MONDAY NIGHT INTO EARLY
TUESDAY. THERMAL PROFILES ARE COLD ENOUGH FOR SNOW TO THE NORTHWEST
OF THE I-95 CORRIDOR...BUT THE BEST LIFT IS FOCUSED JUST SOUTHEAST
OF THIS AREA...AND THE SYSTEM COULD TRACK FURTHER TO THE SOUTH PER
12Z UKMET MODEL. STILL A LOT OF UNCERTAINTY WITH ULTIMATE TRACK.

WEDNESDAY...
A MID-LEVEL RIDGE WILL MOVE THROUGH THE REGION TUESDAY NIGHT INTO
EARLY WEDNESDAY LEADING TO A BRIEF RESPITE BETWEEN WEATHER SYSTEMS.
THEN A MID-LEVEL TROUGH IS PROJECTED TO BECOME NEGATIVELY TILTED
OVER THE OHIO VALLEY ON WED...LEADING TO A MERIDIONAL FLOW ALONG
THE EAST COAST...WITH THE ENTIRE COLUMN EXPECTED TO BE WELL ABOVE
FREEZING ACROSS THE CWA FAVORING A RAIN EVENT. THERE ARE SEVERAL
INGREDIENTS COMING TOGETHER FOR HEAVY RAIN. IN PARTICULAR...DEEP
GULF MOISTURE...LOW-LEVEL ISENTROPIC LIFT...MID-LEVEL PVA...AND
THE RIGHT-REAR QUADRANT OF A 140 KNOT UPPER-LEVEL JET JUST NORTH.
THE SYSTEM SHOULD BE FAIRLY PROGRESSIVE BUT WILL HAVE TO MONITOR
POTENTIAL FOR FLOODING.

THU AND FRI...
LOW-PRESSURE MOVES NORTHWARD INTO QUEBEC AND HIGH-PRESSURE BEGINS
TO BUILD IN. TEMPERATURES WILL RETURN TO SEASONABLE LEVELS AND
THERE COULD BE SNOW SHOWERS IN THE BLUSTERY NORTHWEST FLOW.

&&

.AVIATION /23Z FRIDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

THE 00Z TAFS TAKE CIGS DOWN TO MVFR LEVELS TONIGHT FROM THE KPHL
AREA AIRPORTS NORTHWESTWARD WITH IMPROVEMENT ON SATURDAY. ITS BEEN
TOUGH TO SHAKE THIS STRATOCU LEVEL CLOUDINESS PATTERN.

FOR TONIGHT. LOW CLOUDS ADVANCING IN FROM THE HIGHER TERRAIN
AIRPORTS ARE STILL HEADING INTO THE TERMINALS. WE BRING MVFR CIG
POTENTIAL FROM THE GET GO AT KABE AND KRDG (HIER CONFIDENCE
OVERNIGHT) AND BRING IT DOWN TO THE KPHL METRO AIRPORTS AFTER 05Z.
WE LEAVE KACY AND KMIV VFR. WINDS WILL BE LIGHT FROM THE
NORTHWEST. NO VSBY RESTRICTIONS EXPECTED.

ON SATURDAY, PREDICTING THE MVFR CIG TO BECOME SCATTERED DURING
THE MORNING FROM THE KPHL METRO AIRPORTS NWWD WITH A CIRRUS CIG
ABOVE. KACY AND KMIV NOT EXPECTING A MVFR CIG. IT WILL BE A WEAK
PRESSURE PATTERN AND WINDS WILL BE LIGHT. A NORTHERLY DIRECTION
IS FAVORED, BUT SPEEDS ARE EXPECTED TO REMAIN BELOW 10 KNOTS,
PROBABLY PREDOMINATELY LESS THAN 6 KNOTS AT SOME OF THE MORE
RURAL AIRPORTS AND TERMINALS.

OUTLOOK...
SATURDAY NIGHT AND SUNDAY...VFR CONDITIONS EXPECTED.
MONDAY AND TUESDAY...IFR POSSIBLE IN SHRA AND SHSN.
WEDNESDAY...IFR POSSIBLE IN RAIN AND FOG.

&&

.MARINE...
SUB-SCA CONDS ARE EXPECTED FOR THE NEXT 24 HOURS AT LEAST. SMWHT
GUST NW WINDS THIS EVENING WILL GRADUALLY DIMINISH TONIGHT THROUGH
SATURDAY AS A RIDGE OF HIGH PRES MOVES OVERHEAD. SEAS ARE
CURRENTLY RUNNING 2 TO 3 FT BUT THEY SHOULD GRADUALLY DIMINISH
ALSO.

OUTLOOK...
SUNDAY AND MONDAY...SUB-SCA CONDITIONS EXPECTED.
TUESDAY...SCA MAY BE NEEDED FOR BUILDING SEAS.
WEDNESDAY...GALE WARNING MAY BE NEEDED.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANCK
NEAR TERM...AMC/GIGI
SHORT TERM...AMC
LONG TERM...FRANCK
AVIATION...FRANCK/GIGI
MARINE...AMC/FRANCK







000
FXUS61 KPHI 192328
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
628 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE JUST NORTH OF LAKE SUPERIOR WILL GRADUALLY MOVE
EASTWARD INTO NORTHERN NEW ENGLAND THRU MONDAY. A WAVE OF LOW
PRESSURE WILL FORM ALONG THE MID-ATLANTIC COASTLINE ON MONDAY
AND MOVE NORTHEASTWARD JUST OFFSHORE ON TUESDAY. MEANWHILE...
A STRONG AREA OF LOW-PRESSURE WILL FORM OVER THE MISSISSIPPI
VALLEY AND MOVE THRU THE GREAT LAKES REGION DURING THE MIDDLE
OF THE WEEK...BRINGING A STRONG COLD FRONT THRU THE REGION
BY THURSDAY. HIGH PRESSURE IS PROJECTED TO BUILD IN ON FRIDAY.

&&

.NEAR TERM /THROUGH SATURDAY/...
WITH THIS ESTF UPDATE WE ADJUSTED SKY COVER GOING MORE PESSIMISTIC
NORTH BASED ON CURRENT POSNING OF CLOUDS AND THE 18Z MODELS
BRINGING AN 850MB SHORT WAVE THRU THE NORTHERN PART OF OUR CWA. WE
UPPED TEMPS SLIGHTLY NORTH, LEFT THE REST AS IS. WITH LIGHT WINDS,
CONFIDENCE ABOUT TEMPS DUE TO CLOUD COVER UNCERTAINTY IS LOWER
THAN AVERAGE.

FOR TONIGHT...NW WINDS WILL CONTINUE BUT WILL BECOME LIGHTER AS
CANADIAN LOW PRES MOVES AWAY AND HIGH PRES MOVES CLOSED WITH
RESULTING RELAXED PRES GRAD.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH 6 PM SATURDAY/...
FOR SATURDAY...HIGH PRES CENTERED OVER CANADA SHIFTS EWD FROM
ONTARIO INTO QUEBEC. A RIDGE AXIS IS FCST TO EXTEND SWD THROUGH THE
MID-ATLANTIC REGION RESULTING IN ONLY LIGHT NLY WINDS. SOME LOW-LVL
MOISTURE SHOULD REMAIN TRAPPED BELOW THE LARGE-SCALE SUBSIDENCE
INVERSION BUT HARD TO SAY HOW EXTENSIVE ANY LOW CLOUDS MAY BE. THE
12-KM NAM SHOWS A THIN LOW CLOUD LAYER DEVELOPING DURG THE DAY BUT
HIGHER-RES ARW/NMM AND THE GFS DO NOT. THERE WILL BE SOME HIGHER
CLOUDS ALSO ASSOCD WITH THE SHRTWV NOW MOVING ENEWD OUT OF THE SRN
PLAINS...HWVR POPS REMAIN NEAR ZERO.

&&

.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
HIGHLIGHTS...

* SLIGHT CHANCE OF SNOW SHOWERS SUNDAY MORNING MAINLY NORTH.
* SNOW POSSIBLE NORTHWEST OF THE I-95 CORRIDOR LATE MONDAY
  THRU EARLY TUESDAY.
* POTENTIAL FOR HEAVY RAIN INCREASING ON CHRISTMAS EVE DAY.

OVERVIEW...

MID-LEVEL BLOCKING PATTERN OVER NOAM BEGINS TO DISLODGE IN RESPONSE
JET ENERGY MOVING INTO THE PACIFIC NORTHWEST THIS WEEKEND...CARVING
OUT A DEEP TROUGH OVER THE MS VALLEY EARLY EARLY NEXT WEEK...WHICH
LEADS TO INCLEMENT WEATHER IN THE TUESDAY THRU WEDNESDAY TIME FRAME.

DETAILS...

SUNDAY...
SHORTWAVE LIFTING THROUGH THE REGION EARLY IN THE DAY MAY GENERATE
ENOUGH LIFT ALONG WITH MARGINAL MOISTURE IN THE COLUMN TO PRODUCE
SOME LIGHT SNOW SHOWERS...MAINLY DURING THE PRE-DAWN HOURS. LITTLE
IF ANY ACCUMULATION EXPECTED AS MOISTURE IS VERY LIMITED. RIDGING
THEN BUILDS IN SO FAIR WEATHER IS EXPECTED THE REMAINDER OF THE DAY.

MONDAY AND TUESDAY...
HIGH PRESSURE ANCHORS ALONG THE LEE OF THE APPALACHIANS. A SOUTHERN
STREAM SHORTWAVE WILL INDUCE LOW-PRESSURE OF THE MID-ATLANTIC COAST.
MODELS BRING QPF NORTHWARD INTO THE AREA ON MONDAY NIGHT INTO EARLY
TUESDAY. THERMAL PROFILES ARE COLD ENOUGH FOR SNOW TO THE NORTHWEST
OF THE I-95 CORRIDOR...BUT THE BEST LIFT IS FOCUSED JUST SOUTHEAST
OF THIS AREA...AND THE SYSTEM COULD TRACK FURTHER TO THE SOUTH PER
12Z UKMET MODEL. STILL A LOT OF UNCERTAINTY WITH ULTIMATE TRACK.

WEDNESDAY...
A MID-LEVEL RIDGE WILL MOVE THROUGH THE REGION TUESDAY NIGHT INTO
EARLY WEDNESDAY LEADING TO A BRIEF RESPITE BETWEEN WEATHER SYSTEMS.
THEN A MID-LEVEL TROUGH IS PROJECTED TO BECOME NEGATIVELY TILTED
OVER THE OHIO VALLEY ON WED...LEADING TO A MERIDIONAL FLOW ALONG
THE EAST COAST...WITH THE ENTIRE COLUMN EXPECTED TO BE WELL ABOVE
FREEZING ACROSS THE CWA FAVORING A RAIN EVENT. THERE ARE SEVERAL
INGREDIENTS COMING TOGETHER FOR HEAVY RAIN. IN PARTICULAR...DEEP
GULF MOISTURE...LOW-LEVEL ISENTROPIC LIFT...MID-LEVEL PVA...AND
THE RIGHT-REAR QUADRANT OF A 140 KNOT UPPER-LEVEL JET JUST NORTH.
THE SYSTEM SHOULD BE FAIRLY PROGRESSIVE BUT WILL HAVE TO MONITOR
POTENTIAL FOR FLOODING.

THU AND FRI...
LOW-PRESSURE MOVES NORTHWARD INTO QUEBEC AND HIGH-PRESSURE BEGINS
TO BUILD IN. TEMPERATURES WILL RETURN TO SEASONABLE LEVELS AND
THERE COULD BE SNOW SHOWERS IN THE BLUSTERY NORTHWEST FLOW.

&&

.AVIATION /23Z FRIDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

THE 00Z TAFS TAKE CIGS DOWN TO MVFR LEVELS TONIGHT FROM THE KPHL
AREA AIRPORTS NORTHWESTWARD WITH IMPROVEMENT ON SATURDAY. ITS BEEN
TOUGH TO SHAKE THIS STRATOCU LEVEL CLOUDINESS PATTERN.

FOR TONIGHT. LOW CLOUDS ADVANCING IN FROM THE HIGHER TERRAIN
AIRPORTS ARE STILL HEADING INTO THE TERMINALS. WE BRING MVFR CIG
POTENTIAL FROM THE GET GO AT KABE AND KRDG (HIER CONFIDENCE
OVERNIGHT) AND BRING IT DOWN TO THE KPHL METRO AIRPORTS AFTER 05Z.
WE LEAVE KACY AND KMIV VFR. WINDS WILL BE LIGHT FROM THE
NORTHWEST. NO VSBY RESTRICTIONS EXPECTED.

ON SATURDAY, PREDICTING THE MVFR CIG TO BECOME SCATTERED DURING
THE MORNING FROM THE KPHL METRO AIRPORTS NWWD WITH A CIRRUS CIG
ABOVE. KACY AND KMIV NOT EXPECTING A MVFR CIG. IT WILL BE A WEAK
PRESSURE PATTERN AND WINDS WILL BE LIGHT. A NORTHERLY DIRECTION
IS FAVORED, BUT SPEEDS ARE EXPECTED TO REMAIN BELOW 10 KNOTS,
PROBABLY PREDOMINATELY LESS THAN 6 KNOTS AT SOME OF THE MORE
RURAL AIRPORTS AND TERMINALS.

OUTLOOK...
SATURDAY NIGHT AND SUNDAY...VFR CONDITIONS EXPECTED.
MONDAY AND TUESDAY...IFR POSSIBLE IN SHRA AND SHSN.
WEDNESDAY...IFR POSSIBLE IN RAIN AND FOG.

&&

.MARINE...
SUB-SCA CONDS ARE EXPECTED FOR THE NEXT 24 HOURS AT LEAST. SMWHT
GUST NW WINDS THIS EVENING WILL GRADUALLY DIMINISH TONIGHT THROUGH
SATURDAY AS A RIDGE OF HIGH PRES MOVES OVERHEAD. SEAS ARE
CURRENTLY RUNNING 2 TO 3 FT BUT THEY SHOULD GRADUALLY DIMINISH
ALSO.

OUTLOOK...
SUNDAY AND MONDAY...SUB-SCA CONDITIONS EXPECTED.
TUESDAY...SCA MAY BE NEEDED FOR BUILDING SEAS.
WEDNESDAY...GALE WARNING MAY BE NEEDED.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANCK
NEAR TERM...AMC/GIGI
SHORT TERM...AMC
LONG TERM...FRANCK
AVIATION...FRANCK/GIGI
MARINE...AMC/FRANCK







000
FXUS61 KPHI 192328
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
628 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE JUST NORTH OF LAKE SUPERIOR WILL GRADUALLY MOVE
EASTWARD INTO NORTHERN NEW ENGLAND THRU MONDAY. A WAVE OF LOW
PRESSURE WILL FORM ALONG THE MID-ATLANTIC COASTLINE ON MONDAY
AND MOVE NORTHEASTWARD JUST OFFSHORE ON TUESDAY. MEANWHILE...
A STRONG AREA OF LOW-PRESSURE WILL FORM OVER THE MISSISSIPPI
VALLEY AND MOVE THRU THE GREAT LAKES REGION DURING THE MIDDLE
OF THE WEEK...BRINGING A STRONG COLD FRONT THRU THE REGION
BY THURSDAY. HIGH PRESSURE IS PROJECTED TO BUILD IN ON FRIDAY.

&&

.NEAR TERM /THROUGH SATURDAY/...
WITH THIS ESTF UPDATE WE ADJUSTED SKY COVER GOING MORE PESSIMISTIC
NORTH BASED ON CURRENT POSNING OF CLOUDS AND THE 18Z MODELS
BRINGING AN 850MB SHORT WAVE THRU THE NORTHERN PART OF OUR CWA. WE
UPPED TEMPS SLIGHTLY NORTH, LEFT THE REST AS IS. WITH LIGHT WINDS,
CONFIDENCE ABOUT TEMPS DUE TO CLOUD COVER UNCERTAINTY IS LOWER
THAN AVERAGE.

FOR TONIGHT...NW WINDS WILL CONTINUE BUT WILL BECOME LIGHTER AS
CANADIAN LOW PRES MOVES AWAY AND HIGH PRES MOVES CLOSED WITH
RESULTING RELAXED PRES GRAD.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH 6 PM SATURDAY/...
FOR SATURDAY...HIGH PRES CENTERED OVER CANADA SHIFTS EWD FROM
ONTARIO INTO QUEBEC. A RIDGE AXIS IS FCST TO EXTEND SWD THROUGH THE
MID-ATLANTIC REGION RESULTING IN ONLY LIGHT NLY WINDS. SOME LOW-LVL
MOISTURE SHOULD REMAIN TRAPPED BELOW THE LARGE-SCALE SUBSIDENCE
INVERSION BUT HARD TO SAY HOW EXTENSIVE ANY LOW CLOUDS MAY BE. THE
12-KM NAM SHOWS A THIN LOW CLOUD LAYER DEVELOPING DURG THE DAY BUT
HIGHER-RES ARW/NMM AND THE GFS DO NOT. THERE WILL BE SOME HIGHER
CLOUDS ALSO ASSOCD WITH THE SHRTWV NOW MOVING ENEWD OUT OF THE SRN
PLAINS...HWVR POPS REMAIN NEAR ZERO.

&&

.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
HIGHLIGHTS...

* SLIGHT CHANCE OF SNOW SHOWERS SUNDAY MORNING MAINLY NORTH.
* SNOW POSSIBLE NORTHWEST OF THE I-95 CORRIDOR LATE MONDAY
  THRU EARLY TUESDAY.
* POTENTIAL FOR HEAVY RAIN INCREASING ON CHRISTMAS EVE DAY.

OVERVIEW...

MID-LEVEL BLOCKING PATTERN OVER NOAM BEGINS TO DISLODGE IN RESPONSE
JET ENERGY MOVING INTO THE PACIFIC NORTHWEST THIS WEEKEND...CARVING
OUT A DEEP TROUGH OVER THE MS VALLEY EARLY EARLY NEXT WEEK...WHICH
LEADS TO INCLEMENT WEATHER IN THE TUESDAY THRU WEDNESDAY TIME FRAME.

DETAILS...

SUNDAY...
SHORTWAVE LIFTING THROUGH THE REGION EARLY IN THE DAY MAY GENERATE
ENOUGH LIFT ALONG WITH MARGINAL MOISTURE IN THE COLUMN TO PRODUCE
SOME LIGHT SNOW SHOWERS...MAINLY DURING THE PRE-DAWN HOURS. LITTLE
IF ANY ACCUMULATION EXPECTED AS MOISTURE IS VERY LIMITED. RIDGING
THEN BUILDS IN SO FAIR WEATHER IS EXPECTED THE REMAINDER OF THE DAY.

MONDAY AND TUESDAY...
HIGH PRESSURE ANCHORS ALONG THE LEE OF THE APPALACHIANS. A SOUTHERN
STREAM SHORTWAVE WILL INDUCE LOW-PRESSURE OF THE MID-ATLANTIC COAST.
MODELS BRING QPF NORTHWARD INTO THE AREA ON MONDAY NIGHT INTO EARLY
TUESDAY. THERMAL PROFILES ARE COLD ENOUGH FOR SNOW TO THE NORTHWEST
OF THE I-95 CORRIDOR...BUT THE BEST LIFT IS FOCUSED JUST SOUTHEAST
OF THIS AREA...AND THE SYSTEM COULD TRACK FURTHER TO THE SOUTH PER
12Z UKMET MODEL. STILL A LOT OF UNCERTAINTY WITH ULTIMATE TRACK.

WEDNESDAY...
A MID-LEVEL RIDGE WILL MOVE THROUGH THE REGION TUESDAY NIGHT INTO
EARLY WEDNESDAY LEADING TO A BRIEF RESPITE BETWEEN WEATHER SYSTEMS.
THEN A MID-LEVEL TROUGH IS PROJECTED TO BECOME NEGATIVELY TILTED
OVER THE OHIO VALLEY ON WED...LEADING TO A MERIDIONAL FLOW ALONG
THE EAST COAST...WITH THE ENTIRE COLUMN EXPECTED TO BE WELL ABOVE
FREEZING ACROSS THE CWA FAVORING A RAIN EVENT. THERE ARE SEVERAL
INGREDIENTS COMING TOGETHER FOR HEAVY RAIN. IN PARTICULAR...DEEP
GULF MOISTURE...LOW-LEVEL ISENTROPIC LIFT...MID-LEVEL PVA...AND
THE RIGHT-REAR QUADRANT OF A 140 KNOT UPPER-LEVEL JET JUST NORTH.
THE SYSTEM SHOULD BE FAIRLY PROGRESSIVE BUT WILL HAVE TO MONITOR
POTENTIAL FOR FLOODING.

THU AND FRI...
LOW-PRESSURE MOVES NORTHWARD INTO QUEBEC AND HIGH-PRESSURE BEGINS
TO BUILD IN. TEMPERATURES WILL RETURN TO SEASONABLE LEVELS AND
THERE COULD BE SNOW SHOWERS IN THE BLUSTERY NORTHWEST FLOW.

&&

.AVIATION /23Z FRIDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

THE 00Z TAFS TAKE CIGS DOWN TO MVFR LEVELS TONIGHT FROM THE KPHL
AREA AIRPORTS NORTHWESTWARD WITH IMPROVEMENT ON SATURDAY. ITS BEEN
TOUGH TO SHAKE THIS STRATOCU LEVEL CLOUDINESS PATTERN.

FOR TONIGHT. LOW CLOUDS ADVANCING IN FROM THE HIGHER TERRAIN
AIRPORTS ARE STILL HEADING INTO THE TERMINALS. WE BRING MVFR CIG
POTENTIAL FROM THE GET GO AT KABE AND KRDG (HIER CONFIDENCE
OVERNIGHT) AND BRING IT DOWN TO THE KPHL METRO AIRPORTS AFTER 05Z.
WE LEAVE KACY AND KMIV VFR. WINDS WILL BE LIGHT FROM THE
NORTHWEST. NO VSBY RESTRICTIONS EXPECTED.

ON SATURDAY, PREDICTING THE MVFR CIG TO BECOME SCATTERED DURING
THE MORNING FROM THE KPHL METRO AIRPORTS NWWD WITH A CIRRUS CIG
ABOVE. KACY AND KMIV NOT EXPECTING A MVFR CIG. IT WILL BE A WEAK
PRESSURE PATTERN AND WINDS WILL BE LIGHT. A NORTHERLY DIRECTION
IS FAVORED, BUT SPEEDS ARE EXPECTED TO REMAIN BELOW 10 KNOTS,
PROBABLY PREDOMINATELY LESS THAN 6 KNOTS AT SOME OF THE MORE
RURAL AIRPORTS AND TERMINALS.

OUTLOOK...
SATURDAY NIGHT AND SUNDAY...VFR CONDITIONS EXPECTED.
MONDAY AND TUESDAY...IFR POSSIBLE IN SHRA AND SHSN.
WEDNESDAY...IFR POSSIBLE IN RAIN AND FOG.

&&

.MARINE...
SUB-SCA CONDS ARE EXPECTED FOR THE NEXT 24 HOURS AT LEAST. SMWHT
GUST NW WINDS THIS EVENING WILL GRADUALLY DIMINISH TONIGHT THROUGH
SATURDAY AS A RIDGE OF HIGH PRES MOVES OVERHEAD. SEAS ARE
CURRENTLY RUNNING 2 TO 3 FT BUT THEY SHOULD GRADUALLY DIMINISH
ALSO.

OUTLOOK...
SUNDAY AND MONDAY...SUB-SCA CONDITIONS EXPECTED.
TUESDAY...SCA MAY BE NEEDED FOR BUILDING SEAS.
WEDNESDAY...GALE WARNING MAY BE NEEDED.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANCK
NEAR TERM...AMC/GIGI
SHORT TERM...AMC
LONG TERM...FRANCK
AVIATION...FRANCK/GIGI
MARINE...AMC/FRANCK







000
FXUS61 KPBZ 192320
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
620 PM EST FRI DEC 19 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
WITH 615PM UPDATE...HAVE MADE ONLY MINOR CHANGES TO SKY AND
HOURLY TEMPERATURE FORECASTS. STRATUS HAS NOT SHOWN ANY SIGNS OF
SCATTERING OUT YET...AND WILL CONTINUE MOSTLY CLOUDY FORECAST AT
THIS POINT. PREVIOUS DISCUSSION FOLLOWS.

THE UPPER TROUGH WILL DEPART EAST AND BE REPLACED BY RIDGING
TONIGHT. MODEL PROFILES SUGGEST THAT SOME MOISTURE WILL REMAIN
TRAPPED UNDER THE BUILDING UPPER RIDGE...PREVENTING US FROM
CLEARING OUT THIS EVENING. THIS ISN`T COMPLETELY CLEAR CUT...BUT
WILL OPT TO KEEP MOSTLY CLOUDY WORDING UNLESS SATELLITE
OBSERVATIONS SHOW OTHERWISE. DID DROP TEMPS FOR THE REST OF THE
AFTERNOON AS CLOUD COVER SHOULD KEEP TEMPERATURES FROM WARMING
MUCH ABOVE CURRENT VALUES. LOWS TONIGHT WERE KEPT NEAR MET
GUIDANCE.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
HIGH PRESSURE RIDGE WILL SETTLE OVER THE NORTHEASTERN CONUS FOR
MUCH OF THE WEEKEND. A FAST MOVING SYSTEM WILL BE SUPPRESSED TO
THE SOUTH SATURDAY BUT SOME MID-HIGH DECK MAY REPLACE THE LOW
DECK...MAINTAINING MOSTLY CLOUDY SKIES THROUGH MUCH OF THE DAY.
WITH NEARLY STAGNANT 850HPA TEMPERATURES AND MINIMAL SUN
TOMORROW...EXPECT HIGHS WILL NOT SURPASS THE LOW TO MID 30`S.
HOWEVER...SOUTHERLY FLOW AND WARM ADVECTION WILL RETURN FOR SUNDAY
AND MONDAY BRINGING TEMPERATURES TO NEAR OR JUST ABOVE NORMAL
VALUES.

ON MONDAY...WE WILL BE IN THE SQUEEZE BETWEEN TWO SYSTEMS. ONE LOW
WILL BE DEVELOPING ALONG THE GULF COAST...WHILE ANOTHER LOW AND
DEEPENING UPPER TROUGH WILL SINK SOUTHWARD OVER THE CENTRAL US.
THIS LOW OVER THE CENTRAL PLAINS WILL HELP TO AMPLIFY THE UPPER
PATTERN...EJECTING THE SOUTHERN SYSTEM NORTHWARD. AT THIS POINT
THE BULK OF THE MOISTURE WITH THE SOUTHERN SYSTEM SHOULD REMAIN
EAST...JUST BRUSHING OUR EASTERN MOUNTAINS OF WV/MD UNTIL THE COLD
FRONT WITH THE DEEPENING LOW APPROACHES. MAINTAINED CHANCE POPS
FOR THE RIDGES WITH LOWER POPS FURTHER NORTH AND WEST THROUGH
MONDAY. WHILE THE MID LEVELS WILL BE WARMING...CANNOT RULE OUT A
RAIN/SNOW MIX INITIALLY MONDAY MORNING OVER THE RIDGES BEFORE
CHANGING TO ALL RAIN. SOME FREEZING RAIN COULD ALSO BE OF CONCERN
IN ANY SHELTERED VALLEYS...BUT FOR NOW WILL LEAVE THIS OUT.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MODELS ARE IN GENERAL AGREEMENT ON DEEPENING UPPER LEVEL CLOSED LOW
OVER THE GREAT LAKES TUESDAY THROUGH THURSDAY WITH PERIODS OF RAIN
INTO WEDNESDAY UNTIL COLD FRONT WILL CHANGE PRECIP OVER TO SNOW
SHOWERS LATER WEDNESDAY AND THURSDAY. WINDS WILL BE ON THE
INCREASE THURSDAY AS SURFACE LOW WRAPS UP NORTH OF THE REGION. QPF
ON THE FRONT SIDE OF SYSTEM WILL BE NEAR AN INCH...WHICH SHOULD
NOT PRODUCE ANY SIGNIFICANT PROBLEMS. BACKLASH SNOW WEDNESDAY
NIGHT INTO THURSDAY WILL BE LIGHT WITH ONLY MINOR ACCUMULATIONS
EXPECTED. FLOW BEHIND COLD FRONT LOOKS TO STAY SOUTHWESTERLY WHICH
LOOKS TO LIMIT LAKE ENHANCED AMOUNTS ALONG I-80 AND THE RIDGES.
COLDER TEMPERATURES WILL THEN MODERATE FRIDAY AS MID LEVEL FLOW
QUICKLY BECOMES ZONAL.

&&

.AVIATION /23Z FRIDAY THROUGH WEDNESDAY/...
PERVASIVE STRATUS COVERS ALL SITES THIS EVENING...WHILE BOUNDARY
LAYER MOISTURE HAS DROPPED OFF FROM EARLIER TODAY. GIVEN STRONG
INVERSIONS...STRATUS SEEMS LIKELY TO CONTINUE FOR THE NEXT DAY AT
LEAST...HOWEVER GIVEN A BIT WIDER DEWPOINT DEPRESSIONS...LIGHT
PRECIPITATION CHANCES SEEM VERY LOW. MVFR CONDITIONS SEEM LIKELY
TO CONTINUE. FRIES


OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY AND WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$







000
FXUS61 KPBZ 192320
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
620 PM EST FRI DEC 19 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
WITH 615PM UPDATE...HAVE MADE ONLY MINOR CHANGES TO SKY AND
HOURLY TEMPERATURE FORECASTS. STRATUS HAS NOT SHOWN ANY SIGNS OF
SCATTERING OUT YET...AND WILL CONTINUE MOSTLY CLOUDY FORECAST AT
THIS POINT. PREVIOUS DISCUSSION FOLLOWS.

THE UPPER TROUGH WILL DEPART EAST AND BE REPLACED BY RIDGING
TONIGHT. MODEL PROFILES SUGGEST THAT SOME MOISTURE WILL REMAIN
TRAPPED UNDER THE BUILDING UPPER RIDGE...PREVENTING US FROM
CLEARING OUT THIS EVENING. THIS ISN`T COMPLETELY CLEAR CUT...BUT
WILL OPT TO KEEP MOSTLY CLOUDY WORDING UNLESS SATELLITE
OBSERVATIONS SHOW OTHERWISE. DID DROP TEMPS FOR THE REST OF THE
AFTERNOON AS CLOUD COVER SHOULD KEEP TEMPERATURES FROM WARMING
MUCH ABOVE CURRENT VALUES. LOWS TONIGHT WERE KEPT NEAR MET
GUIDANCE.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
HIGH PRESSURE RIDGE WILL SETTLE OVER THE NORTHEASTERN CONUS FOR
MUCH OF THE WEEKEND. A FAST MOVING SYSTEM WILL BE SUPPRESSED TO
THE SOUTH SATURDAY BUT SOME MID-HIGH DECK MAY REPLACE THE LOW
DECK...MAINTAINING MOSTLY CLOUDY SKIES THROUGH MUCH OF THE DAY.
WITH NEARLY STAGNANT 850HPA TEMPERATURES AND MINIMAL SUN
TOMORROW...EXPECT HIGHS WILL NOT SURPASS THE LOW TO MID 30`S.
HOWEVER...SOUTHERLY FLOW AND WARM ADVECTION WILL RETURN FOR SUNDAY
AND MONDAY BRINGING TEMPERATURES TO NEAR OR JUST ABOVE NORMAL
VALUES.

ON MONDAY...WE WILL BE IN THE SQUEEZE BETWEEN TWO SYSTEMS. ONE LOW
WILL BE DEVELOPING ALONG THE GULF COAST...WHILE ANOTHER LOW AND
DEEPENING UPPER TROUGH WILL SINK SOUTHWARD OVER THE CENTRAL US.
THIS LOW OVER THE CENTRAL PLAINS WILL HELP TO AMPLIFY THE UPPER
PATTERN...EJECTING THE SOUTHERN SYSTEM NORTHWARD. AT THIS POINT
THE BULK OF THE MOISTURE WITH THE SOUTHERN SYSTEM SHOULD REMAIN
EAST...JUST BRUSHING OUR EASTERN MOUNTAINS OF WV/MD UNTIL THE COLD
FRONT WITH THE DEEPENING LOW APPROACHES. MAINTAINED CHANCE POPS
FOR THE RIDGES WITH LOWER POPS FURTHER NORTH AND WEST THROUGH
MONDAY. WHILE THE MID LEVELS WILL BE WARMING...CANNOT RULE OUT A
RAIN/SNOW MIX INITIALLY MONDAY MORNING OVER THE RIDGES BEFORE
CHANGING TO ALL RAIN. SOME FREEZING RAIN COULD ALSO BE OF CONCERN
IN ANY SHELTERED VALLEYS...BUT FOR NOW WILL LEAVE THIS OUT.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MODELS ARE IN GENERAL AGREEMENT ON DEEPENING UPPER LEVEL CLOSED LOW
OVER THE GREAT LAKES TUESDAY THROUGH THURSDAY WITH PERIODS OF RAIN
INTO WEDNESDAY UNTIL COLD FRONT WILL CHANGE PRECIP OVER TO SNOW
SHOWERS LATER WEDNESDAY AND THURSDAY. WINDS WILL BE ON THE
INCREASE THURSDAY AS SURFACE LOW WRAPS UP NORTH OF THE REGION. QPF
ON THE FRONT SIDE OF SYSTEM WILL BE NEAR AN INCH...WHICH SHOULD
NOT PRODUCE ANY SIGNIFICANT PROBLEMS. BACKLASH SNOW WEDNESDAY
NIGHT INTO THURSDAY WILL BE LIGHT WITH ONLY MINOR ACCUMULATIONS
EXPECTED. FLOW BEHIND COLD FRONT LOOKS TO STAY SOUTHWESTERLY WHICH
LOOKS TO LIMIT LAKE ENHANCED AMOUNTS ALONG I-80 AND THE RIDGES.
COLDER TEMPERATURES WILL THEN MODERATE FRIDAY AS MID LEVEL FLOW
QUICKLY BECOMES ZONAL.

&&

.AVIATION /23Z FRIDAY THROUGH WEDNESDAY/...
PERVASIVE STRATUS COVERS ALL SITES THIS EVENING...WHILE BOUNDARY
LAYER MOISTURE HAS DROPPED OFF FROM EARLIER TODAY. GIVEN STRONG
INVERSIONS...STRATUS SEEMS LIKELY TO CONTINUE FOR THE NEXT DAY AT
LEAST...HOWEVER GIVEN A BIT WIDER DEWPOINT DEPRESSIONS...LIGHT
PRECIPITATION CHANCES SEEM VERY LOW. MVFR CONDITIONS SEEM LIKELY
TO CONTINUE. FRIES


OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY AND WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$






000
FXUS61 KPBZ 192113
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
413 PM EST FRI DEC 19 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
THE UPPER TROUGH WILL DEPART EAST AND BE REPLACED BY RIDGING
TONIGHT. MODEL PROFILES SUGGEST THAT SOME MOISTURE WILL REMAIN
TRAPPED UNDER THE BUILDING UPPER RIDGE...PREVENTING US FROM
CLEARING OUT THIS EVENING. THIS ISN`T COMPLETELY CLEAR CUT...BUT
WILL OPT TO KEEP MOSTLY CLOUDY WORDING UNLESS SATELLITE
OBSERVATIONS SHOW OTHERWISE. DID DROP TEMPS FOR THE REST OF THE
AFTERNOON AS CLOUD COVER SHOULD KEEP TEMPERATURES FROM WARMING
MUCH ABOVE CURRENT VALUES. LOWS TONIGHT WERE KEPT NEAR MET
GUIDANCE.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
HIGH PRESSURE RIDGE WILL SETTLE OVER THE NORTHEASTERN CONUS FOR
MUCH OF THE WEEKEND. A FAST MOVING SYSTEM WILL BE SUPPRESSED TO
THE SOUTH SATURDAY BUT SOME MID-HIGH DECK MAY REPLACE THE LOW
DECK...MAINTAINING MOSTLY CLOUDY SKIES THROUGH MUCH OF THE DAY.
WITH NEARLY STAGNANT 850HPA TEMPERATURES AND MINIMAL SUN
TOMORROW...EXPECT HIGHS WILL NOT SURPASS THE LOW TO MID 30`S.
HOWEVER...SOUTHERLY FLOW AND WARM ADVECTION WILL RETURN FOR SUNDAY
AND MONDAY BRINGING TEMPERATURES TO NEAR OR JUST ABOVE NORMAL
VALUES.

ON MONDAY...WE WILL BE IN THE SQUEEZE BETWEEN TWO SYSTEMS. ONE LOW
WILL BE DEVELOPING ALONG THE GULF COAST...WHILE ANOTHER LOW AND
DEEPENING UPPER TROUGH WILL SINK SOUTHWARD OVER THE CENTRAL US.
THIS LOW OVER THE CENTRAL PLAINS WILL HELP TO AMPLIFY THE UPPER
PATTERN...EJECTING THE SOUTHERN SYSTEM NORTHWARD. AT THIS POINT
THE BULK OF THE MOISTURE WITH THE SOUTHERN SYSTEM SHOULD REMAIN
EAST...JUST BRUSHING OUR EASTERN MOUNTAINS OF WV/MD UNTIL THE COLD
FRONT WITH THE DEEPENING LOW APPROACHES. MAINTAINED CHANCE POPS
FOR THE RIDGES WITH LOWER POPS FURTHER NORTH AND WEST THROUGH
MONDAY. WHILE THE MID LEVELS WILL BE WARMING...CANNOT RULE OUT A
RAIN/SNOW MIX INITIALLY MONDAY MORNING OVER THE RIDGES BEFORE
CHANGING TO ALL RAIN. SOME FREEZING RAIN COULD ALSO BE OF CONCERN
IN ANY SHELTERED VALLEYS...BUT FOR NOW WILL LEAVE THIS OUT.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MODELS ARE IN GENERAL AGREEMENT ON DEEPENING UPPER LEVEL CLOSED LOW
OVER THE GREAT LAKES TUESDAY THROUGH THURSDAY WITH PERIODS OF RAIN
INTO WEDNESDAY UNTIL COLD FRONT WILL CHANGE PRECIP OVER TO SNOW
SHOWERS LATER WEDNESDAY AND THURSDAY. WINDS WILL BE ON THE
INCREASE THURSDAY AS SURFACE LOW WRAPS UP NORTH OF THE REGION. QPF
ON THE FRONT SIDE OF SYSTEM WILL BE NEAR AN INCH...WHICH SHOULD
NOT PRODUCE ANY SIGNIFICANT PROBLEMS. BACKLASH SNOW WEDNESDAY
NIGHT INTO THURSDAY WILL BE LIGHT WITH ONLY MINOR ACCUMULATIONS
EXPECTED. FLOW BEHIND COLD FRONT LOOKS TO STAY SOUTHWESTERLY WHICH
LOOKS TO LIMIT LAKE ENHANCED AMOUNTS ALONG I-80 AND THE RIDGES.
COLDER TEMPERATURES WILL THEN MODERATE FRIDAY AS MID LEVEL FLOW
QUICKLY BECOMES ZONAL.

&&

.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
GENERAL MVFR EXPECTED THROUGH TONIGHT.


OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY AND WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$











000
FXUS61 KPBZ 192113
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
413 PM EST FRI DEC 19 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
THE UPPER TROUGH WILL DEPART EAST AND BE REPLACED BY RIDGING
TONIGHT. MODEL PROFILES SUGGEST THAT SOME MOISTURE WILL REMAIN
TRAPPED UNDER THE BUILDING UPPER RIDGE...PREVENTING US FROM
CLEARING OUT THIS EVENING. THIS ISN`T COMPLETELY CLEAR CUT...BUT
WILL OPT TO KEEP MOSTLY CLOUDY WORDING UNLESS SATELLITE
OBSERVATIONS SHOW OTHERWISE. DID DROP TEMPS FOR THE REST OF THE
AFTERNOON AS CLOUD COVER SHOULD KEEP TEMPERATURES FROM WARMING
MUCH ABOVE CURRENT VALUES. LOWS TONIGHT WERE KEPT NEAR MET
GUIDANCE.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
HIGH PRESSURE RIDGE WILL SETTLE OVER THE NORTHEASTERN CONUS FOR
MUCH OF THE WEEKEND. A FAST MOVING SYSTEM WILL BE SUPPRESSED TO
THE SOUTH SATURDAY BUT SOME MID-HIGH DECK MAY REPLACE THE LOW
DECK...MAINTAINING MOSTLY CLOUDY SKIES THROUGH MUCH OF THE DAY.
WITH NEARLY STAGNANT 850HPA TEMPERATURES AND MINIMAL SUN
TOMORROW...EXPECT HIGHS WILL NOT SURPASS THE LOW TO MID 30`S.
HOWEVER...SOUTHERLY FLOW AND WARM ADVECTION WILL RETURN FOR SUNDAY
AND MONDAY BRINGING TEMPERATURES TO NEAR OR JUST ABOVE NORMAL
VALUES.

ON MONDAY...WE WILL BE IN THE SQUEEZE BETWEEN TWO SYSTEMS. ONE LOW
WILL BE DEVELOPING ALONG THE GULF COAST...WHILE ANOTHER LOW AND
DEEPENING UPPER TROUGH WILL SINK SOUTHWARD OVER THE CENTRAL US.
THIS LOW OVER THE CENTRAL PLAINS WILL HELP TO AMPLIFY THE UPPER
PATTERN...EJECTING THE SOUTHERN SYSTEM NORTHWARD. AT THIS POINT
THE BULK OF THE MOISTURE WITH THE SOUTHERN SYSTEM SHOULD REMAIN
EAST...JUST BRUSHING OUR EASTERN MOUNTAINS OF WV/MD UNTIL THE COLD
FRONT WITH THE DEEPENING LOW APPROACHES. MAINTAINED CHANCE POPS
FOR THE RIDGES WITH LOWER POPS FURTHER NORTH AND WEST THROUGH
MONDAY. WHILE THE MID LEVELS WILL BE WARMING...CANNOT RULE OUT A
RAIN/SNOW MIX INITIALLY MONDAY MORNING OVER THE RIDGES BEFORE
CHANGING TO ALL RAIN. SOME FREEZING RAIN COULD ALSO BE OF CONCERN
IN ANY SHELTERED VALLEYS...BUT FOR NOW WILL LEAVE THIS OUT.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MODELS ARE IN GENERAL AGREEMENT ON DEEPENING UPPER LEVEL CLOSED LOW
OVER THE GREAT LAKES TUESDAY THROUGH THURSDAY WITH PERIODS OF RAIN
INTO WEDNESDAY UNTIL COLD FRONT WILL CHANGE PRECIP OVER TO SNOW
SHOWERS LATER WEDNESDAY AND THURSDAY. WINDS WILL BE ON THE
INCREASE THURSDAY AS SURFACE LOW WRAPS UP NORTH OF THE REGION. QPF
ON THE FRONT SIDE OF SYSTEM WILL BE NEAR AN INCH...WHICH SHOULD
NOT PRODUCE ANY SIGNIFICANT PROBLEMS. BACKLASH SNOW WEDNESDAY
NIGHT INTO THURSDAY WILL BE LIGHT WITH ONLY MINOR ACCUMULATIONS
EXPECTED. FLOW BEHIND COLD FRONT LOOKS TO STAY SOUTHWESTERLY WHICH
LOOKS TO LIMIT LAKE ENHANCED AMOUNTS ALONG I-80 AND THE RIDGES.
COLDER TEMPERATURES WILL THEN MODERATE FRIDAY AS MID LEVEL FLOW
QUICKLY BECOMES ZONAL.

&&

.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
GENERAL MVFR EXPECTED THROUGH TONIGHT.


OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY AND WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$











000
FXUS61 KPBZ 192113
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
413 PM EST FRI DEC 19 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
THE UPPER TROUGH WILL DEPART EAST AND BE REPLACED BY RIDGING
TONIGHT. MODEL PROFILES SUGGEST THAT SOME MOISTURE WILL REMAIN
TRAPPED UNDER THE BUILDING UPPER RIDGE...PREVENTING US FROM
CLEARING OUT THIS EVENING. THIS ISN`T COMPLETELY CLEAR CUT...BUT
WILL OPT TO KEEP MOSTLY CLOUDY WORDING UNLESS SATELLITE
OBSERVATIONS SHOW OTHERWISE. DID DROP TEMPS FOR THE REST OF THE
AFTERNOON AS CLOUD COVER SHOULD KEEP TEMPERATURES FROM WARMING
MUCH ABOVE CURRENT VALUES. LOWS TONIGHT WERE KEPT NEAR MET
GUIDANCE.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
HIGH PRESSURE RIDGE WILL SETTLE OVER THE NORTHEASTERN CONUS FOR
MUCH OF THE WEEKEND. A FAST MOVING SYSTEM WILL BE SUPPRESSED TO
THE SOUTH SATURDAY BUT SOME MID-HIGH DECK MAY REPLACE THE LOW
DECK...MAINTAINING MOSTLY CLOUDY SKIES THROUGH MUCH OF THE DAY.
WITH NEARLY STAGNANT 850HPA TEMPERATURES AND MINIMAL SUN
TOMORROW...EXPECT HIGHS WILL NOT SURPASS THE LOW TO MID 30`S.
HOWEVER...SOUTHERLY FLOW AND WARM ADVECTION WILL RETURN FOR SUNDAY
AND MONDAY BRINGING TEMPERATURES TO NEAR OR JUST ABOVE NORMAL
VALUES.

ON MONDAY...WE WILL BE IN THE SQUEEZE BETWEEN TWO SYSTEMS. ONE LOW
WILL BE DEVELOPING ALONG THE GULF COAST...WHILE ANOTHER LOW AND
DEEPENING UPPER TROUGH WILL SINK SOUTHWARD OVER THE CENTRAL US.
THIS LOW OVER THE CENTRAL PLAINS WILL HELP TO AMPLIFY THE UPPER
PATTERN...EJECTING THE SOUTHERN SYSTEM NORTHWARD. AT THIS POINT
THE BULK OF THE MOISTURE WITH THE SOUTHERN SYSTEM SHOULD REMAIN
EAST...JUST BRUSHING OUR EASTERN MOUNTAINS OF WV/MD UNTIL THE COLD
FRONT WITH THE DEEPENING LOW APPROACHES. MAINTAINED CHANCE POPS
FOR THE RIDGES WITH LOWER POPS FURTHER NORTH AND WEST THROUGH
MONDAY. WHILE THE MID LEVELS WILL BE WARMING...CANNOT RULE OUT A
RAIN/SNOW MIX INITIALLY MONDAY MORNING OVER THE RIDGES BEFORE
CHANGING TO ALL RAIN. SOME FREEZING RAIN COULD ALSO BE OF CONCERN
IN ANY SHELTERED VALLEYS...BUT FOR NOW WILL LEAVE THIS OUT.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MODELS ARE IN GENERAL AGREEMENT ON DEEPENING UPPER LEVEL CLOSED LOW
OVER THE GREAT LAKES TUESDAY THROUGH THURSDAY WITH PERIODS OF RAIN
INTO WEDNESDAY UNTIL COLD FRONT WILL CHANGE PRECIP OVER TO SNOW
SHOWERS LATER WEDNESDAY AND THURSDAY. WINDS WILL BE ON THE
INCREASE THURSDAY AS SURFACE LOW WRAPS UP NORTH OF THE REGION. QPF
ON THE FRONT SIDE OF SYSTEM WILL BE NEAR AN INCH...WHICH SHOULD
NOT PRODUCE ANY SIGNIFICANT PROBLEMS. BACKLASH SNOW WEDNESDAY
NIGHT INTO THURSDAY WILL BE LIGHT WITH ONLY MINOR ACCUMULATIONS
EXPECTED. FLOW BEHIND COLD FRONT LOOKS TO STAY SOUTHWESTERLY WHICH
LOOKS TO LIMIT LAKE ENHANCED AMOUNTS ALONG I-80 AND THE RIDGES.
COLDER TEMPERATURES WILL THEN MODERATE FRIDAY AS MID LEVEL FLOW
QUICKLY BECOMES ZONAL.

&&

.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
GENERAL MVFR EXPECTED THROUGH TONIGHT.


OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY AND WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$











000
FXUS61 KPBZ 192113
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
413 PM EST FRI DEC 19 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
THE UPPER TROUGH WILL DEPART EAST AND BE REPLACED BY RIDGING
TONIGHT. MODEL PROFILES SUGGEST THAT SOME MOISTURE WILL REMAIN
TRAPPED UNDER THE BUILDING UPPER RIDGE...PREVENTING US FROM
CLEARING OUT THIS EVENING. THIS ISN`T COMPLETELY CLEAR CUT...BUT
WILL OPT TO KEEP MOSTLY CLOUDY WORDING UNLESS SATELLITE
OBSERVATIONS SHOW OTHERWISE. DID DROP TEMPS FOR THE REST OF THE
AFTERNOON AS CLOUD COVER SHOULD KEEP TEMPERATURES FROM WARMING
MUCH ABOVE CURRENT VALUES. LOWS TONIGHT WERE KEPT NEAR MET
GUIDANCE.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
HIGH PRESSURE RIDGE WILL SETTLE OVER THE NORTHEASTERN CONUS FOR
MUCH OF THE WEEKEND. A FAST MOVING SYSTEM WILL BE SUPPRESSED TO
THE SOUTH SATURDAY BUT SOME MID-HIGH DECK MAY REPLACE THE LOW
DECK...MAINTAINING MOSTLY CLOUDY SKIES THROUGH MUCH OF THE DAY.
WITH NEARLY STAGNANT 850HPA TEMPERATURES AND MINIMAL SUN
TOMORROW...EXPECT HIGHS WILL NOT SURPASS THE LOW TO MID 30`S.
HOWEVER...SOUTHERLY FLOW AND WARM ADVECTION WILL RETURN FOR SUNDAY
AND MONDAY BRINGING TEMPERATURES TO NEAR OR JUST ABOVE NORMAL
VALUES.

ON MONDAY...WE WILL BE IN THE SQUEEZE BETWEEN TWO SYSTEMS. ONE LOW
WILL BE DEVELOPING ALONG THE GULF COAST...WHILE ANOTHER LOW AND
DEEPENING UPPER TROUGH WILL SINK SOUTHWARD OVER THE CENTRAL US.
THIS LOW OVER THE CENTRAL PLAINS WILL HELP TO AMPLIFY THE UPPER
PATTERN...EJECTING THE SOUTHERN SYSTEM NORTHWARD. AT THIS POINT
THE BULK OF THE MOISTURE WITH THE SOUTHERN SYSTEM SHOULD REMAIN
EAST...JUST BRUSHING OUR EASTERN MOUNTAINS OF WV/MD UNTIL THE COLD
FRONT WITH THE DEEPENING LOW APPROACHES. MAINTAINED CHANCE POPS
FOR THE RIDGES WITH LOWER POPS FURTHER NORTH AND WEST THROUGH
MONDAY. WHILE THE MID LEVELS WILL BE WARMING...CANNOT RULE OUT A
RAIN/SNOW MIX INITIALLY MONDAY MORNING OVER THE RIDGES BEFORE
CHANGING TO ALL RAIN. SOME FREEZING RAIN COULD ALSO BE OF CONCERN
IN ANY SHELTERED VALLEYS...BUT FOR NOW WILL LEAVE THIS OUT.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MODELS ARE IN GENERAL AGREEMENT ON DEEPENING UPPER LEVEL CLOSED LOW
OVER THE GREAT LAKES TUESDAY THROUGH THURSDAY WITH PERIODS OF RAIN
INTO WEDNESDAY UNTIL COLD FRONT WILL CHANGE PRECIP OVER TO SNOW
SHOWERS LATER WEDNESDAY AND THURSDAY. WINDS WILL BE ON THE
INCREASE THURSDAY AS SURFACE LOW WRAPS UP NORTH OF THE REGION. QPF
ON THE FRONT SIDE OF SYSTEM WILL BE NEAR AN INCH...WHICH SHOULD
NOT PRODUCE ANY SIGNIFICANT PROBLEMS. BACKLASH SNOW WEDNESDAY
NIGHT INTO THURSDAY WILL BE LIGHT WITH ONLY MINOR ACCUMULATIONS
EXPECTED. FLOW BEHIND COLD FRONT LOOKS TO STAY SOUTHWESTERLY WHICH
LOOKS TO LIMIT LAKE ENHANCED AMOUNTS ALONG I-80 AND THE RIDGES.
COLDER TEMPERATURES WILL THEN MODERATE FRIDAY AS MID LEVEL FLOW
QUICKLY BECOMES ZONAL.

&&

.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
GENERAL MVFR EXPECTED THROUGH TONIGHT.


OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY AND WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$











000
FXUS61 KPHI 192051
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
351 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE JUST NORTH OF LAKE SUPERIOR WILL GRADUALLY MOVE
EASTWARD INTO NORTHERN NEW ENGLAND THRU MONDAY. A WAVE OF LOW
PRESSURE WILL FORM ALONG THE MID-ATLANTIC COASTLINE ON MONDAY
AND MOVE NORTHEASTWARD JUST OFFSHORE ON TUESDAY. MEANWHILE...
A STRONG AREA OF LOW-PRESSURE WILL FORM OVER THE MISSISSIPPI
VALLEY AND MOVE THRU THE GREAT LAKES REGION DURING THE MIDDLE
OF THE WEEK...BRINGING A STRONG COLD FRONT THRU THE REGION
BY THURSDAY. HIGH PRESSURE IS PROJECTED TO BUILD IN ON FRIDAY.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY/...
EXTENSIVE LOW CLOUD DECK THAT COVERED THE AREA THIS MORNING HAS
ERODED CONSIDERABLY THIS AFTN. CLOUD COVER PERSISTS OVER DELMARVA
AND OVER NWRN NJ AND ADJ PA. GIVEN THE NWLY LOW-LVL FLOW...THINK THE
CLOUDS DOWN SOUTH WILL CONT TO ERODE WHILE THE NRN AREA WILL BE MORE
PERSISTENT INTO THIS EVENING. TEMPS IN CLEARING AREAS HAVE RESPONDED
ONLY SLIGHTLY DUE TO THE LOW DEC SUN ANGLE.

FOR TONIGHT...NW WINDS WILL CONTINUE BUT WILL BECOME LIGHTER AS
CANADIAN LOW PRES MOVES AWAY AND HIGH PRES MOVES CLOSED WITH
RESULTING RELAXED PRES GRAD. MOSTLY CLEAR TO PARTLY CLOUDY SKIES
TONIGHT SHOULD ALLOW FOR DECENT COOLING WITH OVERNIGHT MINS GENLY 5
TO 10 DEGS COOLER THAN LAST NIGHT.

&&

.SHORT TERM /6 AM TO 6 PM SATURDAY/...
FOR SATURDAY...HIGH PRES CENTERED OVER CANADA SHIFTS EWD FROM
ONTARIO INTO QUEBEC. A RIDGE AXIS IS FCST TO EXTEND SWD THROUGH THE
MID-ATLANTIC REGION RESULTING IN ONLY LIGHT NLY WINDS. SOME LOW-LVL
MOISTURE SHOULD REMAIN TRAPPED BELOW THE LARGE-SCALE SUBSIDENCE
INVERSION BUT HARD TO SAY HOW EXTENSIVE ANY LOW CLOUDS MAY BE. THE
12-KM NAM SHOWS A THIN LOW CLOUD LAYER DEVELOPING DURG THE DAY BUT
HIGHER-RES ARW/NMM AND THE GFS DO NOT. THERE WILL BE SOME HIGHER
CLOUDS ALSO ASSOCD WITH THE SHRTWV NOW MOVING ENEWD OUT OF THE SRN
PLAINS...HWVR POPS REMAIN NEAR ZERO.

&&

.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
HIGHLIGHTS...

* SLIGHT CHANCE OF SNOW SHOWERS SUNDAY MORNING MAINLY NORTH.
* SNOW POSSIBLE NORTHWEST OF THE I-95 CORRIDOR LATE MONDAY
  THRU EARLY TUESDAY.
* POTENTIAL FOR HEAVY RAIN INCREASING ON CHRISTMAS EVE DAY.

OVERVIEW...

MID-LEVEL BLOCKING PATTERN OVER NOAM BEGINS TO DISLODGE IN RESPONSE
JET ENERGY MOVING INTO THE PACIFIC NORTHWEST THIS WEEKEND...CARVING
OUT A DEEP TROUGH OVER THE MS VALLEY EARLY EARLY NEXT WEEK...WHICH
LEADS TO INCLEMENT WEATHER IN THE TUESDAY THRU WEDNESDAY TIME FRAME.

DETAILS...

SUNDAY...
SHORTWAVE LIFTING THROUGH THE REGION EARLY IN THE DAY MAY GENERATE
ENOUGH LIFT ALONG WITH MARGINAL MOISTURE IN THE COLUMN TO PRODUCE
SOME LIGHT SNOW SHOWERS...MAINLY DURING THE PRE-DAWN HOURS. LITTLE
IF ANY ACCUMULATION EXPECTED AS MOISTURE IS VERY LIMITED. RIDGING
THEN BUILDS IN SO FAIR WEATHER IS EXPECTED THE REMAINDER OF THE DAY.

MONDAY AND TUESDAY...
HIGH PRESSURE ANCHORS ALONG THE LEE OF THE APPALACHIANS. A SOUTHERN
STREAM SHORTWAVE WILL INDUCE LOW-PRESSURE OF THE MID-ATLANTIC COAST.
MODELS BRING QPF NORTHWARD INTO THE AREA ON MONDAY NIGHT INTO EARLY
TUESDAY. THERMAL PROFILES ARE COLD ENOUGH FOR SNOW TO THE NORTHWEST
OF THE I-95 CORRIDOR...BUT THE BEST LIFT IS FOCUSED JUST SOUTHEAST
OF THIS AREA...AND THE SYSTEM COULD TRACK FURTHER TO THE SOUTH PER
12Z UKMET MODEL. STILL A LOT OF UNCERTAINTY WITH ULTIMATE TRACK.

WEDNESDAY...
A MID-LEVEL RIDGE WILL MOVE THROUGH THE REGION TUESDAY NIGHT INTO
EARLY WEDNESDAY LEADING TO A BRIEF RESPITE BETWEEN WEATHER SYSTEMS.
THEN A MID-LEVEL TROUGH IS PROJECTED TO BECOME NEGATIVELY TILTED
OVER THE OHIO VALLEY ON WED...LEADING TO A MERIDIONAL FLOW ALONG
THE EAST COAST...WITH THE ENTIRE COLUMN EXPECTED TO BE WELL ABOVE
FREEZING ACROSS THE CWA FAVORING A RAIN EVENT. THERE ARE SEVERAL
INGREDIENTS COMING TOGETHER FOR HEAVY RAIN. IN PARTICULAR...DEEP
GULF MOISTURE...LOW-LEVEL ISENTROPIC LIFT...MID-LEVEL PVA...AND
THE RIGHT-REAR QUADRANT OF A 140 KNOT UPPER-LEVEL JET JUST NORTH.
THE SYSTEM SHOULD BE FAIRLY PROGRESSIVE BUT WILL HAVE TO MONITOR
POTENTIAL FOR FLOODING.

THU AND FRI...
LOW-PRESSURE MOVES NORTHWARD INTO QUEBEC AND HIGH-PRESSURE BEGINS
TO BUILD IN. TEMPERATURES WILL RETURN TO SEASONABLE LEVELS AND
THERE COULD BE SNOW SHOWERS IN THE BLUSTERY NORTHWEST FLOW.

&&

.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
SMWHAT GUSTY NW WINDS WILL CONTINUE FOR A COUPLE MORE HOURS BUT
SHOULD DIE DOWN SOME BY SUNSET AS THE SFC COOLS/DECOUPLES AND THE
LARGER SCALE PRES GRADIENT RELAXES. LIGHT NW WINDS WILL CONTINUE
OVERNIGHT. THE EARLIER LOW CLOUDS HAVE MOSTLY DISSIPATED AND ATTM
ARE NOT EXPECTED TO RETURN TONIGHT. SOME LOW CLOUDS ARE POSSIBLE
ON SATURDAY BUT SHOULD NOT BE AS EXENSIVE AS THIS MORNING. WINDS
ON SATURDAY WILL BE LIGHT NORTHERLY AS A HIGH PRESSURE RIDGE MOVES
OVER HEAD.

OUTLOOK...
SUNDAY...VFR CONDITIONS EXPECTED.
MONDAY AND TUESDAY...IFR POSSIBLE IN SHRA AND SHSN.
WEDNESDAY...IFR POSSIBLE IN RA AND FG.

&&

.MARINE...
SUB-SCA CONDS ARE EXPECTED FOR THE NEXT 24 HOURS AT LEAST. SMWHT
GUST NW WINDS THIS EVENING WILL GRADUALLY DIMINISH TONIGHT THROUGH
SATURDAY AS A RIDGE OF HIGH PRES MOVES OVERHEAD. SEAS ARE
CURRENTLY RUNNING 2 TO 3 FT BUT THEY SHOULD GRADUALLY DIMINISH
ALSO.

OUTLOOK...

SUNDAY AND MONDAY...SUB-SCA CONDITIONS EXPECTED.
TUESDAY...SCA MAY BE NEEDED FOR BUILDING SEAS.
WEDNESDAY...GALE WARNING MAY BE NEEDED.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANCK
NEAR TERM...AMC
SHORT TERM...AMC
LONG TERM...FRANCK
AVIATION...AMC/FRANCK
MARINE...AMC/FRANCK






000
FXUS61 KPHI 192051
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
351 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE JUST NORTH OF LAKE SUPERIOR WILL GRADUALLY MOVE
EASTWARD INTO NORTHERN NEW ENGLAND THRU MONDAY. A WAVE OF LOW
PRESSURE WILL FORM ALONG THE MID-ATLANTIC COASTLINE ON MONDAY
AND MOVE NORTHEASTWARD JUST OFFSHORE ON TUESDAY. MEANWHILE...
A STRONG AREA OF LOW-PRESSURE WILL FORM OVER THE MISSISSIPPI
VALLEY AND MOVE THRU THE GREAT LAKES REGION DURING THE MIDDLE
OF THE WEEK...BRINGING A STRONG COLD FRONT THRU THE REGION
BY THURSDAY. HIGH PRESSURE IS PROJECTED TO BUILD IN ON FRIDAY.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY/...
EXTENSIVE LOW CLOUD DECK THAT COVERED THE AREA THIS MORNING HAS
ERODED CONSIDERABLY THIS AFTN. CLOUD COVER PERSISTS OVER DELMARVA
AND OVER NWRN NJ AND ADJ PA. GIVEN THE NWLY LOW-LVL FLOW...THINK THE
CLOUDS DOWN SOUTH WILL CONT TO ERODE WHILE THE NRN AREA WILL BE MORE
PERSISTENT INTO THIS EVENING. TEMPS IN CLEARING AREAS HAVE RESPONDED
ONLY SLIGHTLY DUE TO THE LOW DEC SUN ANGLE.

FOR TONIGHT...NW WINDS WILL CONTINUE BUT WILL BECOME LIGHTER AS
CANADIAN LOW PRES MOVES AWAY AND HIGH PRES MOVES CLOSED WITH
RESULTING RELAXED PRES GRAD. MOSTLY CLEAR TO PARTLY CLOUDY SKIES
TONIGHT SHOULD ALLOW FOR DECENT COOLING WITH OVERNIGHT MINS GENLY 5
TO 10 DEGS COOLER THAN LAST NIGHT.

&&

.SHORT TERM /6 AM TO 6 PM SATURDAY/...
FOR SATURDAY...HIGH PRES CENTERED OVER CANADA SHIFTS EWD FROM
ONTARIO INTO QUEBEC. A RIDGE AXIS IS FCST TO EXTEND SWD THROUGH THE
MID-ATLANTIC REGION RESULTING IN ONLY LIGHT NLY WINDS. SOME LOW-LVL
MOISTURE SHOULD REMAIN TRAPPED BELOW THE LARGE-SCALE SUBSIDENCE
INVERSION BUT HARD TO SAY HOW EXTENSIVE ANY LOW CLOUDS MAY BE. THE
12-KM NAM SHOWS A THIN LOW CLOUD LAYER DEVELOPING DURG THE DAY BUT
HIGHER-RES ARW/NMM AND THE GFS DO NOT. THERE WILL BE SOME HIGHER
CLOUDS ALSO ASSOCD WITH THE SHRTWV NOW MOVING ENEWD OUT OF THE SRN
PLAINS...HWVR POPS REMAIN NEAR ZERO.

&&

.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
HIGHLIGHTS...

* SLIGHT CHANCE OF SNOW SHOWERS SUNDAY MORNING MAINLY NORTH.
* SNOW POSSIBLE NORTHWEST OF THE I-95 CORRIDOR LATE MONDAY
  THRU EARLY TUESDAY.
* POTENTIAL FOR HEAVY RAIN INCREASING ON CHRISTMAS EVE DAY.

OVERVIEW...

MID-LEVEL BLOCKING PATTERN OVER NOAM BEGINS TO DISLODGE IN RESPONSE
JET ENERGY MOVING INTO THE PACIFIC NORTHWEST THIS WEEKEND...CARVING
OUT A DEEP TROUGH OVER THE MS VALLEY EARLY EARLY NEXT WEEK...WHICH
LEADS TO INCLEMENT WEATHER IN THE TUESDAY THRU WEDNESDAY TIME FRAME.

DETAILS...

SUNDAY...
SHORTWAVE LIFTING THROUGH THE REGION EARLY IN THE DAY MAY GENERATE
ENOUGH LIFT ALONG WITH MARGINAL MOISTURE IN THE COLUMN TO PRODUCE
SOME LIGHT SNOW SHOWERS...MAINLY DURING THE PRE-DAWN HOURS. LITTLE
IF ANY ACCUMULATION EXPECTED AS MOISTURE IS VERY LIMITED. RIDGING
THEN BUILDS IN SO FAIR WEATHER IS EXPECTED THE REMAINDER OF THE DAY.

MONDAY AND TUESDAY...
HIGH PRESSURE ANCHORS ALONG THE LEE OF THE APPALACHIANS. A SOUTHERN
STREAM SHORTWAVE WILL INDUCE LOW-PRESSURE OF THE MID-ATLANTIC COAST.
MODELS BRING QPF NORTHWARD INTO THE AREA ON MONDAY NIGHT INTO EARLY
TUESDAY. THERMAL PROFILES ARE COLD ENOUGH FOR SNOW TO THE NORTHWEST
OF THE I-95 CORRIDOR...BUT THE BEST LIFT IS FOCUSED JUST SOUTHEAST
OF THIS AREA...AND THE SYSTEM COULD TRACK FURTHER TO THE SOUTH PER
12Z UKMET MODEL. STILL A LOT OF UNCERTAINTY WITH ULTIMATE TRACK.

WEDNESDAY...
A MID-LEVEL RIDGE WILL MOVE THROUGH THE REGION TUESDAY NIGHT INTO
EARLY WEDNESDAY LEADING TO A BRIEF RESPITE BETWEEN WEATHER SYSTEMS.
THEN A MID-LEVEL TROUGH IS PROJECTED TO BECOME NEGATIVELY TILTED
OVER THE OHIO VALLEY ON WED...LEADING TO A MERIDIONAL FLOW ALONG
THE EAST COAST...WITH THE ENTIRE COLUMN EXPECTED TO BE WELL ABOVE
FREEZING ACROSS THE CWA FAVORING A RAIN EVENT. THERE ARE SEVERAL
INGREDIENTS COMING TOGETHER FOR HEAVY RAIN. IN PARTICULAR...DEEP
GULF MOISTURE...LOW-LEVEL ISENTROPIC LIFT...MID-LEVEL PVA...AND
THE RIGHT-REAR QUADRANT OF A 140 KNOT UPPER-LEVEL JET JUST NORTH.
THE SYSTEM SHOULD BE FAIRLY PROGRESSIVE BUT WILL HAVE TO MONITOR
POTENTIAL FOR FLOODING.

THU AND FRI...
LOW-PRESSURE MOVES NORTHWARD INTO QUEBEC AND HIGH-PRESSURE BEGINS
TO BUILD IN. TEMPERATURES WILL RETURN TO SEASONABLE LEVELS AND
THERE COULD BE SNOW SHOWERS IN THE BLUSTERY NORTHWEST FLOW.

&&

.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
SMWHAT GUSTY NW WINDS WILL CONTINUE FOR A COUPLE MORE HOURS BUT
SHOULD DIE DOWN SOME BY SUNSET AS THE SFC COOLS/DECOUPLES AND THE
LARGER SCALE PRES GRADIENT RELAXES. LIGHT NW WINDS WILL CONTINUE
OVERNIGHT. THE EARLIER LOW CLOUDS HAVE MOSTLY DISSIPATED AND ATTM
ARE NOT EXPECTED TO RETURN TONIGHT. SOME LOW CLOUDS ARE POSSIBLE
ON SATURDAY BUT SHOULD NOT BE AS EXENSIVE AS THIS MORNING. WINDS
ON SATURDAY WILL BE LIGHT NORTHERLY AS A HIGH PRESSURE RIDGE MOVES
OVER HEAD.

OUTLOOK...
SUNDAY...VFR CONDITIONS EXPECTED.
MONDAY AND TUESDAY...IFR POSSIBLE IN SHRA AND SHSN.
WEDNESDAY...IFR POSSIBLE IN RA AND FG.

&&

.MARINE...
SUB-SCA CONDS ARE EXPECTED FOR THE NEXT 24 HOURS AT LEAST. SMWHT
GUST NW WINDS THIS EVENING WILL GRADUALLY DIMINISH TONIGHT THROUGH
SATURDAY AS A RIDGE OF HIGH PRES MOVES OVERHEAD. SEAS ARE
CURRENTLY RUNNING 2 TO 3 FT BUT THEY SHOULD GRADUALLY DIMINISH
ALSO.

OUTLOOK...

SUNDAY AND MONDAY...SUB-SCA CONDITIONS EXPECTED.
TUESDAY...SCA MAY BE NEEDED FOR BUILDING SEAS.
WEDNESDAY...GALE WARNING MAY BE NEEDED.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...FRANCK
NEAR TERM...AMC
SHORT TERM...AMC
LONG TERM...FRANCK
AVIATION...AMC/FRANCK
MARINE...AMC/FRANCK







000
FXUS61 KCTP 192033
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
333 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER THE WESTERN GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND...BRINGING DRY WEATHER WITH
LIGHTER WIND. A DEEP UPPER TROUGH AND ASSOCIATED SFC LOW WILL LIFT
NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE OF NEXT WEEK
LIKELY BRINGING US RAIN AND WIND FOR CHRISTMAS EVE...THEN BLUSTERY
AND COLDER CONDITIONS FOR CHRISTMAS DAY WITH SCATTERED SNOW
SHOWERS.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK TRAPPED BELOW A
MODERATELY STRONG SUBSIDENCE INVERSION /BASED AT AROUND 2-3KFT
AGL/ WILL PERSIST ACROSS MUCH OF NORTHERN AND WESTERN PENNSYLVANIA
LATE TODAY INTO SATURDAY...WHILE PARTIAL CLEARING OCCURS ACROSS
THE LOWER SUSQ VALLEY AND SURROUNDING AREAS.

TEMPS WILL REMAIN STEADY THROUGH LATE THIS AFTERNOON UNDER THE
10-15 KT NWRLY FLOW. READINGS WILL VARY FROM THE MID TO UPPER 20S
ACROSS THE NORTHERN AND WESTERN MOUNTAINS...TO THE LOWER 40S IN
THE SOUTHEAST.

A WEAK SFC RIDGE WILL MOVE TO NEAR THE PENN/OHIO BORDER BY 12Z
SATURDAY...BUT THE WEAK WESTERLY ISENTROPIC LIFT ALONG THE 285K
THETA SFC...AND SOME SHALLOW MOISTURE BEING ADVECTED SWD INTO THE
NRN MTNS OF PENN FROM LAKE ONTARIO...WILL MAINTAIN MOSTLY CLOUDY
TO CLOUDY SKIES. LITTLE MORE THAN A FEW FLURRIES OR SPOTTY -FZDZ
WILL FALL FROM THIS THIN CLOUD LAYER ACROSS THE HIGHER TERRAIN OF
THE LAURELS AND INVOF KBFD.

AFTER A PTLY CLOUDY LATE AFTERNOON AND EVENING IN THE SE PART OF
THE CWA...A BKN LAYER OF STRATO CU IS EXPECTED TO DRIFT SE /OR
FORM/ ACROSS THE REGION OVERNIGHT.

DUE TO THE NW-SE GRADIENT OF DECREASING CLOUDS...LOW TEMPS AT
DAYBREAK SAT WILL BE IN A RATHER TIGHT RANGE...FROM THE UPPER
TEENS TO LOWER 20S ACROSS THE MOUNTAINS...TO THE LOWER 20S IN THE
SE

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
A RIDGE OF HIGH PRESSURE...LIGHTER WIND...AND ASSOC DRIER AIR
MASS WILL BUILD EAST ACROSS THE STATE SATURDAY...PROVIDING THE
AREA WITH FAIR WEATHER.

HIGH RES MODEL DATA CONTINUES TO PAINT A MOSTLY CLOUDY PICTURE FOR
MUCH OF THE REGION SATURDAY INTO SATURDAY NIGHT...THOUGH PERIODS
OF SUNSHINE ARE LIKELY THROUGHOUT THE CENTRAL RIDGE AND VALLEY
REGION...AND SUSQUEHANNA RIVER VALLEY.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS OVER THE LOWER/THIN STRATO CU
CLOUD DECK PRESENT ACROSS THE REGION SATURDAY. ALL 12Z OPERATIONAL
MODEL DATA CONTINUES TO SUPPORT A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS NEAR 30 ACROSS THE MTNS...AND MID TO UPPER 30S IN
THE SE.

MOSTLY CLOUDY SKIES WITH LIGHT WIND SAT NIGHT WILL YIELD LOWS IN
THE LOWER 20S ACROSS THE MTNS...AND GENERALLY THE MID 20S
ELSEWHERE.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGH PRES WILL PROVIDE TRANQUIL WEATHER ON SUNDAY...WITH PARTLY TO
MOSTLY SUNNY SKIES AND SEASONABLE TEMPS. AFTER THAT...THE WEATHER
WILL BECOME INCREASINGLY UNSETTLED AS NEXT WEEK PROGRESSES.

CLOUDS WILL INCR SUNDAY NIGHT INTO MONDAY...AS HIGH PRES LOSES
ITS GRIP AND A WEAK AREA OF LOW PRES ORGANIZES OVER THE SERN UNITED
STATES. LIGHT PRECIP WILL WORK NWD INTO PENNSYLVANIA LATE MONDAY
INTO MONDAY NIGHT AND CONTINUE INTO TUES. INITIALLY...CONDS WILL
BE COLD ENOUGH FOR THE POSSIBILITY OF SOME WINTRY PRECIP.
HOWEVER...WARMER AIR WILL MAKE ITS WAY NWD LATER MONDAY NIGHT INTO
TUES AND GRADUALLY CHANGE ANY LINGERING PRECIP OVER TO PLAIN RAIN.

A MORE SIGNIFICANT STORM SYSTEM WILL GET ORGANIZED OVER THE
MISSISSIPPI VALLEY TUES NIGHT BEFORE PUSHING NWD INTO THE GREAT
LAKES ON WED. THIS SYSTEM WILL DRAW EVEN MILDER AIR NWD INTO THE
REGION...AND PROVIDE A RAINY AND BREEZY CHRISTMAS EVE DAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS FROM WEST TO EAST ACROSS PA IS POSSIBLE LATE WED/WED
NIGHT. SCT SNOW SHOWERS WILL CONTINUE INTO THURS ACROSS MAINLY
NRN AND WRN PA.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
OPERATIONAL MODELS AND THE GEFS SHOWING 850HPA TEMPS ALREADY
BEGINNING TO RISE NEXT FRI.

&&

.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
LLVL NWRLY FLOW AND OROGRAPHIC FORCING OF A SHALLOW MOIST LAYER
WILL CONTINUE TO PRODUCE PLENTY OF CLOUDS ACROSS THE NW 1/2 TO
2/3RDS OF THE STATE WITH MAINLY MVFR BKN-OVC CIGS THROUGH
TONIGHT. KJST AND KBFD MAY TEETER ON THE UPPER END OF IFR FOR A
FEW HOURS LATER TONIGHT /AFTER 06Z/. IN CONTRAST...THE SE PENN
AIRFIELDS SUCH AS KMDT...KTHV AND KLNS WILL SEE MAINLY VFR...WITH
SKY CONDITIONS VARYING SCT-BKN030-040.

NORTHWEST WINDS OF 10-15 KTS WITH HIGHER GUSTS WILL DECREASE TO 8
KTS OR LESS LATER TONIGHT AND SATURDAY.

HIGH PRESSURE BUILDS EAST ACROSS PENN SATURDAY...WITH BKN-OVC CIGS
VARYING BETWEEN MVFR OVER THE HIGHER TERRAIN OF THE NORTH AND
WEST...TO SCT-BKN VFR IN THE VALLEYS.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...EVANEGO
AVIATION...LAMBERT




000
FXUS61 KCTP 192033
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
333 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER THE WESTERN GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND...BRINGING DRY WEATHER WITH
LIGHTER WIND. A DEEP UPPER TROUGH AND ASSOCIATED SFC LOW WILL LIFT
NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE OF NEXT WEEK
LIKELY BRINGING US RAIN AND WIND FOR CHRISTMAS EVE...THEN BLUSTERY
AND COLDER CONDITIONS FOR CHRISTMAS DAY WITH SCATTERED SNOW
SHOWERS.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK TRAPPED BELOW A
MODERATELY STRONG SUBSIDENCE INVERSION /BASED AT AROUND 2-3KFT
AGL/ WILL PERSIST ACROSS MUCH OF NORTHERN AND WESTERN PENNSYLVANIA
LATE TODAY INTO SATURDAY...WHILE PARTIAL CLEARING OCCURS ACROSS
THE LOWER SUSQ VALLEY AND SURROUNDING AREAS.

TEMPS WILL REMAIN STEADY THROUGH LATE THIS AFTERNOON UNDER THE
10-15 KT NWRLY FLOW. READINGS WILL VARY FROM THE MID TO UPPER 20S
ACROSS THE NORTHERN AND WESTERN MOUNTAINS...TO THE LOWER 40S IN
THE SOUTHEAST.

A WEAK SFC RIDGE WILL MOVE TO NEAR THE PENN/OHIO BORDER BY 12Z
SATURDAY...BUT THE WEAK WESTERLY ISENTROPIC LIFT ALONG THE 285K
THETA SFC...AND SOME SHALLOW MOISTURE BEING ADVECTED SWD INTO THE
NRN MTNS OF PENN FROM LAKE ONTARIO...WILL MAINTAIN MOSTLY CLOUDY
TO CLOUDY SKIES. LITTLE MORE THAN A FEW FLURRIES OR SPOTTY -FZDZ
WILL FALL FROM THIS THIN CLOUD LAYER ACROSS THE HIGHER TERRAIN OF
THE LAURELS AND INVOF KBFD.

AFTER A PTLY CLOUDY LATE AFTERNOON AND EVENING IN THE SE PART OF
THE CWA...A BKN LAYER OF STRATO CU IS EXPECTED TO DRIFT SE /OR
FORM/ ACROSS THE REGION OVERNIGHT.

DUE TO THE NW-SE GRADIENT OF DECREASING CLOUDS...LOW TEMPS AT
DAYBREAK SAT WILL BE IN A RATHER TIGHT RANGE...FROM THE UPPER
TEENS TO LOWER 20S ACROSS THE MOUNTAINS...TO THE LOWER 20S IN THE
SE

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
A RIDGE OF HIGH PRESSURE...LIGHTER WIND...AND ASSOC DRIER AIR
MASS WILL BUILD EAST ACROSS THE STATE SATURDAY...PROVIDING THE
AREA WITH FAIR WEATHER.

HIGH RES MODEL DATA CONTINUES TO PAINT A MOSTLY CLOUDY PICTURE FOR
MUCH OF THE REGION SATURDAY INTO SATURDAY NIGHT...THOUGH PERIODS
OF SUNSHINE ARE LIKELY THROUGHOUT THE CENTRAL RIDGE AND VALLEY
REGION...AND SUSQUEHANNA RIVER VALLEY.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS OVER THE LOWER/THIN STRATO CU
CLOUD DECK PRESENT ACROSS THE REGION SATURDAY. ALL 12Z OPERATIONAL
MODEL DATA CONTINUES TO SUPPORT A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS NEAR 30 ACROSS THE MTNS...AND MID TO UPPER 30S IN
THE SE.

MOSTLY CLOUDY SKIES WITH LIGHT WIND SAT NIGHT WILL YIELD LOWS IN
THE LOWER 20S ACROSS THE MTNS...AND GENERALLY THE MID 20S
ELSEWHERE.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGH PRES WILL PROVIDE TRANQUIL WEATHER ON SUNDAY...WITH PARTLY TO
MOSTLY SUNNY SKIES AND SEASONABLE TEMPS. AFTER THAT...THE WEATHER
WILL BECOME INCREASINGLY UNSETTLED AS NEXT WEEK PROGRESSES.

CLOUDS WILL INCR SUNDAY NIGHT INTO MONDAY...AS HIGH PRES LOSES
ITS GRIP AND A WEAK AREA OF LOW PRES ORGANIZES OVER THE SERN UNITED
STATES. LIGHT PRECIP WILL WORK NWD INTO PENNSYLVANIA LATE MONDAY
INTO MONDAY NIGHT AND CONTINUE INTO TUES. INITIALLY...CONDS WILL
BE COLD ENOUGH FOR THE POSSIBILITY OF SOME WINTRY PRECIP.
HOWEVER...WARMER AIR WILL MAKE ITS WAY NWD LATER MONDAY NIGHT INTO
TUES AND GRADUALLY CHANGE ANY LINGERING PRECIP OVER TO PLAIN RAIN.

A MORE SIGNIFICANT STORM SYSTEM WILL GET ORGANIZED OVER THE
MISSISSIPPI VALLEY TUES NIGHT BEFORE PUSHING NWD INTO THE GREAT
LAKES ON WED. THIS SYSTEM WILL DRAW EVEN MILDER AIR NWD INTO THE
REGION...AND PROVIDE A RAINY AND BREEZY CHRISTMAS EVE DAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS FROM WEST TO EAST ACROSS PA IS POSSIBLE LATE WED/WED
NIGHT. SCT SNOW SHOWERS WILL CONTINUE INTO THURS ACROSS MAINLY
NRN AND WRN PA.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
OPERATIONAL MODELS AND THE GEFS SHOWING 850HPA TEMPS ALREADY
BEGINNING TO RISE NEXT FRI.

&&

.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
LLVL NWRLY FLOW AND OROGRAPHIC FORCING OF A SHALLOW MOIST LAYER
WILL CONTINUE TO PRODUCE PLENTY OF CLOUDS ACROSS THE NW 1/2 TO
2/3RDS OF THE STATE WITH MAINLY MVFR BKN-OVC CIGS THROUGH
TONIGHT. KJST AND KBFD MAY TEETER ON THE UPPER END OF IFR FOR A
FEW HOURS LATER TONIGHT /AFTER 06Z/. IN CONTRAST...THE SE PENN
AIRFIELDS SUCH AS KMDT...KTHV AND KLNS WILL SEE MAINLY VFR...WITH
SKY CONDITIONS VARYING SCT-BKN030-040.

NORTHWEST WINDS OF 10-15 KTS WITH HIGHER GUSTS WILL DECREASE TO 8
KTS OR LESS LATER TONIGHT AND SATURDAY.

HIGH PRESSURE BUILDS EAST ACROSS PENN SATURDAY...WITH BKN-OVC CIGS
VARYING BETWEEN MVFR OVER THE HIGHER TERRAIN OF THE NORTH AND
WEST...TO SCT-BKN VFR IN THE VALLEYS.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...EVANEGO
AVIATION...LAMBERT




000
FXUS61 KCTP 192033
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
333 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER THE WESTERN GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND...BRINGING DRY WEATHER WITH
LIGHTER WIND. A DEEP UPPER TROUGH AND ASSOCIATED SFC LOW WILL LIFT
NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE OF NEXT WEEK
LIKELY BRINGING US RAIN AND WIND FOR CHRISTMAS EVE...THEN BLUSTERY
AND COLDER CONDITIONS FOR CHRISTMAS DAY WITH SCATTERED SNOW
SHOWERS.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK TRAPPED BELOW A
MODERATELY STRONG SUBSIDENCE INVERSION /BASED AT AROUND 2-3KFT
AGL/ WILL PERSIST ACROSS MUCH OF NORTHERN AND WESTERN PENNSYLVANIA
LATE TODAY INTO SATURDAY...WHILE PARTIAL CLEARING OCCURS ACROSS
THE LOWER SUSQ VALLEY AND SURROUNDING AREAS.

TEMPS WILL REMAIN STEADY THROUGH LATE THIS AFTERNOON UNDER THE
10-15 KT NWRLY FLOW. READINGS WILL VARY FROM THE MID TO UPPER 20S
ACROSS THE NORTHERN AND WESTERN MOUNTAINS...TO THE LOWER 40S IN
THE SOUTHEAST.

A WEAK SFC RIDGE WILL MOVE TO NEAR THE PENN/OHIO BORDER BY 12Z
SATURDAY...BUT THE WEAK WESTERLY ISENTROPIC LIFT ALONG THE 285K
THETA SFC...AND SOME SHALLOW MOISTURE BEING ADVECTED SWD INTO THE
NRN MTNS OF PENN FROM LAKE ONTARIO...WILL MAINTAIN MOSTLY CLOUDY
TO CLOUDY SKIES. LITTLE MORE THAN A FEW FLURRIES OR SPOTTY -FZDZ
WILL FALL FROM THIS THIN CLOUD LAYER ACROSS THE HIGHER TERRAIN OF
THE LAURELS AND INVOF KBFD.

AFTER A PTLY CLOUDY LATE AFTERNOON AND EVENING IN THE SE PART OF
THE CWA...A BKN LAYER OF STRATO CU IS EXPECTED TO DRIFT SE /OR
FORM/ ACROSS THE REGION OVERNIGHT.

DUE TO THE NW-SE GRADIENT OF DECREASING CLOUDS...LOW TEMPS AT
DAYBREAK SAT WILL BE IN A RATHER TIGHT RANGE...FROM THE UPPER
TEENS TO LOWER 20S ACROSS THE MOUNTAINS...TO THE LOWER 20S IN THE
SE

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
A RIDGE OF HIGH PRESSURE...LIGHTER WIND...AND ASSOC DRIER AIR
MASS WILL BUILD EAST ACROSS THE STATE SATURDAY...PROVIDING THE
AREA WITH FAIR WEATHER.

HIGH RES MODEL DATA CONTINUES TO PAINT A MOSTLY CLOUDY PICTURE FOR
MUCH OF THE REGION SATURDAY INTO SATURDAY NIGHT...THOUGH PERIODS
OF SUNSHINE ARE LIKELY THROUGHOUT THE CENTRAL RIDGE AND VALLEY
REGION...AND SUSQUEHANNA RIVER VALLEY.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS OVER THE LOWER/THIN STRATO CU
CLOUD DECK PRESENT ACROSS THE REGION SATURDAY. ALL 12Z OPERATIONAL
MODEL DATA CONTINUES TO SUPPORT A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS NEAR 30 ACROSS THE MTNS...AND MID TO UPPER 30S IN
THE SE.

MOSTLY CLOUDY SKIES WITH LIGHT WIND SAT NIGHT WILL YIELD LOWS IN
THE LOWER 20S ACROSS THE MTNS...AND GENERALLY THE MID 20S
ELSEWHERE.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGH PRES WILL PROVIDE TRANQUIL WEATHER ON SUNDAY...WITH PARTLY TO
MOSTLY SUNNY SKIES AND SEASONABLE TEMPS. AFTER THAT...THE WEATHER
WILL BECOME INCREASINGLY UNSETTLED AS NEXT WEEK PROGRESSES.

CLOUDS WILL INCR SUNDAY NIGHT INTO MONDAY...AS HIGH PRES LOSES
ITS GRIP AND A WEAK AREA OF LOW PRES ORGANIZES OVER THE SERN UNITED
STATES. LIGHT PRECIP WILL WORK NWD INTO PENNSYLVANIA LATE MONDAY
INTO MONDAY NIGHT AND CONTINUE INTO TUES. INITIALLY...CONDS WILL
BE COLD ENOUGH FOR THE POSSIBILITY OF SOME WINTRY PRECIP.
HOWEVER...WARMER AIR WILL MAKE ITS WAY NWD LATER MONDAY NIGHT INTO
TUES AND GRADUALLY CHANGE ANY LINGERING PRECIP OVER TO PLAIN RAIN.

A MORE SIGNIFICANT STORM SYSTEM WILL GET ORGANIZED OVER THE
MISSISSIPPI VALLEY TUES NIGHT BEFORE PUSHING NWD INTO THE GREAT
LAKES ON WED. THIS SYSTEM WILL DRAW EVEN MILDER AIR NWD INTO THE
REGION...AND PROVIDE A RAINY AND BREEZY CHRISTMAS EVE DAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS FROM WEST TO EAST ACROSS PA IS POSSIBLE LATE WED/WED
NIGHT. SCT SNOW SHOWERS WILL CONTINUE INTO THURS ACROSS MAINLY
NRN AND WRN PA.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
OPERATIONAL MODELS AND THE GEFS SHOWING 850HPA TEMPS ALREADY
BEGINNING TO RISE NEXT FRI.

&&

.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
LLVL NWRLY FLOW AND OROGRAPHIC FORCING OF A SHALLOW MOIST LAYER
WILL CONTINUE TO PRODUCE PLENTY OF CLOUDS ACROSS THE NW 1/2 TO
2/3RDS OF THE STATE WITH MAINLY MVFR BKN-OVC CIGS THROUGH
TONIGHT. KJST AND KBFD MAY TEETER ON THE UPPER END OF IFR FOR A
FEW HOURS LATER TONIGHT /AFTER 06Z/. IN CONTRAST...THE SE PENN
AIRFIELDS SUCH AS KMDT...KTHV AND KLNS WILL SEE MAINLY VFR...WITH
SKY CONDITIONS VARYING SCT-BKN030-040.

NORTHWEST WINDS OF 10-15 KTS WITH HIGHER GUSTS WILL DECREASE TO 8
KTS OR LESS LATER TONIGHT AND SATURDAY.

HIGH PRESSURE BUILDS EAST ACROSS PENN SATURDAY...WITH BKN-OVC CIGS
VARYING BETWEEN MVFR OVER THE HIGHER TERRAIN OF THE NORTH AND
WEST...TO SCT-BKN VFR IN THE VALLEYS.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...EVANEGO
AVIATION...LAMBERT




000
FXUS61 KCTP 192033
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
333 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER THE WESTERN GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND...BRINGING DRY WEATHER WITH
LIGHTER WIND. A DEEP UPPER TROUGH AND ASSOCIATED SFC LOW WILL LIFT
NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE OF NEXT WEEK
LIKELY BRINGING US RAIN AND WIND FOR CHRISTMAS EVE...THEN BLUSTERY
AND COLDER CONDITIONS FOR CHRISTMAS DAY WITH SCATTERED SNOW
SHOWERS.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK TRAPPED BELOW A
MODERATELY STRONG SUBSIDENCE INVERSION /BASED AT AROUND 2-3KFT
AGL/ WILL PERSIST ACROSS MUCH OF NORTHERN AND WESTERN PENNSYLVANIA
LATE TODAY INTO SATURDAY...WHILE PARTIAL CLEARING OCCURS ACROSS
THE LOWER SUSQ VALLEY AND SURROUNDING AREAS.

TEMPS WILL REMAIN STEADY THROUGH LATE THIS AFTERNOON UNDER THE
10-15 KT NWRLY FLOW. READINGS WILL VARY FROM THE MID TO UPPER 20S
ACROSS THE NORTHERN AND WESTERN MOUNTAINS...TO THE LOWER 40S IN
THE SOUTHEAST.

A WEAK SFC RIDGE WILL MOVE TO NEAR THE PENN/OHIO BORDER BY 12Z
SATURDAY...BUT THE WEAK WESTERLY ISENTROPIC LIFT ALONG THE 285K
THETA SFC...AND SOME SHALLOW MOISTURE BEING ADVECTED SWD INTO THE
NRN MTNS OF PENN FROM LAKE ONTARIO...WILL MAINTAIN MOSTLY CLOUDY
TO CLOUDY SKIES. LITTLE MORE THAN A FEW FLURRIES OR SPOTTY -FZDZ
WILL FALL FROM THIS THIN CLOUD LAYER ACROSS THE HIGHER TERRAIN OF
THE LAURELS AND INVOF KBFD.

AFTER A PTLY CLOUDY LATE AFTERNOON AND EVENING IN THE SE PART OF
THE CWA...A BKN LAYER OF STRATO CU IS EXPECTED TO DRIFT SE /OR
FORM/ ACROSS THE REGION OVERNIGHT.

DUE TO THE NW-SE GRADIENT OF DECREASING CLOUDS...LOW TEMPS AT
DAYBREAK SAT WILL BE IN A RATHER TIGHT RANGE...FROM THE UPPER
TEENS TO LOWER 20S ACROSS THE MOUNTAINS...TO THE LOWER 20S IN THE
SE

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
A RIDGE OF HIGH PRESSURE...LIGHTER WIND...AND ASSOC DRIER AIR
MASS WILL BUILD EAST ACROSS THE STATE SATURDAY...PROVIDING THE
AREA WITH FAIR WEATHER.

HIGH RES MODEL DATA CONTINUES TO PAINT A MOSTLY CLOUDY PICTURE FOR
MUCH OF THE REGION SATURDAY INTO SATURDAY NIGHT...THOUGH PERIODS
OF SUNSHINE ARE LIKELY THROUGHOUT THE CENTRAL RIDGE AND VALLEY
REGION...AND SUSQUEHANNA RIVER VALLEY.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS OVER THE LOWER/THIN STRATO CU
CLOUD DECK PRESENT ACROSS THE REGION SATURDAY. ALL 12Z OPERATIONAL
MODEL DATA CONTINUES TO SUPPORT A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS NEAR 30 ACROSS THE MTNS...AND MID TO UPPER 30S IN
THE SE.

MOSTLY CLOUDY SKIES WITH LIGHT WIND SAT NIGHT WILL YIELD LOWS IN
THE LOWER 20S ACROSS THE MTNS...AND GENERALLY THE MID 20S
ELSEWHERE.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGH PRES WILL PROVIDE TRANQUIL WEATHER ON SUNDAY...WITH PARTLY TO
MOSTLY SUNNY SKIES AND SEASONABLE TEMPS. AFTER THAT...THE WEATHER
WILL BECOME INCREASINGLY UNSETTLED AS NEXT WEEK PROGRESSES.

CLOUDS WILL INCR SUNDAY NIGHT INTO MONDAY...AS HIGH PRES LOSES
ITS GRIP AND A WEAK AREA OF LOW PRES ORGANIZES OVER THE SERN UNITED
STATES. LIGHT PRECIP WILL WORK NWD INTO PENNSYLVANIA LATE MONDAY
INTO MONDAY NIGHT AND CONTINUE INTO TUES. INITIALLY...CONDS WILL
BE COLD ENOUGH FOR THE POSSIBILITY OF SOME WINTRY PRECIP.
HOWEVER...WARMER AIR WILL MAKE ITS WAY NWD LATER MONDAY NIGHT INTO
TUES AND GRADUALLY CHANGE ANY LINGERING PRECIP OVER TO PLAIN RAIN.

A MORE SIGNIFICANT STORM SYSTEM WILL GET ORGANIZED OVER THE
MISSISSIPPI VALLEY TUES NIGHT BEFORE PUSHING NWD INTO THE GREAT
LAKES ON WED. THIS SYSTEM WILL DRAW EVEN MILDER AIR NWD INTO THE
REGION...AND PROVIDE A RAINY AND BREEZY CHRISTMAS EVE DAY.

AS THIS SYSTEM DRIFTS NWD INTO SRN CANADA...COLDER AIR WILL WRAP
INTO THE REGION ON BLUSTERY WEST WINDS. A CHANGEOVER FROM RAIN TO
SNOW SHOWERS FROM WEST TO EAST ACROSS PA IS POSSIBLE LATE WED/WED
NIGHT. SCT SNOW SHOWERS WILL CONTINUE INTO THURS ACROSS MAINLY
NRN AND WRN PA.

THE CHILLIER AIRMASS LOOKS LIKE IT WILL BE SHORT-LIVED...WITH
OPERATIONAL MODELS AND THE GEFS SHOWING 850HPA TEMPS ALREADY
BEGINNING TO RISE NEXT FRI.

&&

.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
LLVL NWRLY FLOW AND OROGRAPHIC FORCING OF A SHALLOW MOIST LAYER
WILL CONTINUE TO PRODUCE PLENTY OF CLOUDS ACROSS THE NW 1/2 TO
2/3RDS OF THE STATE WITH MAINLY MVFR BKN-OVC CIGS THROUGH
TONIGHT. KJST AND KBFD MAY TEETER ON THE UPPER END OF IFR FOR A
FEW HOURS LATER TONIGHT /AFTER 06Z/. IN CONTRAST...THE SE PENN
AIRFIELDS SUCH AS KMDT...KTHV AND KLNS WILL SEE MAINLY VFR...WITH
SKY CONDITIONS VARYING SCT-BKN030-040.

NORTHWEST WINDS OF 10-15 KTS WITH HIGHER GUSTS WILL DECREASE TO 8
KTS OR LESS LATER TONIGHT AND SATURDAY.

HIGH PRESSURE BUILDS EAST ACROSS PENN SATURDAY...WITH BKN-OVC CIGS
VARYING BETWEEN MVFR OVER THE HIGHER TERRAIN OF THE NORTH AND
WEST...TO SCT-BKN VFR IN THE VALLEYS.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYING INTENSITY...LEADING TO
MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...EVANEGO
AVIATION...LAMBERT




000
FXUS61 KCTP 192007
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
307 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER THE WESTERN GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND...BRINGING DRY WEATHER WITH
LIGHTER WIND. A DEEP UPPER TROUGH AND ASSOCIATED SFC LOW WILL LIFT
NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE OF NEXT WEEK
LIKELY BRINGING US RAIN AND WIND FOR CHRISTMAS EVE...THEN BLUSTERY
AND COLDER CONDITIONS FOR CHRISTMAS DAY WITH SCATTERED SNOW
SHOWERS.

&&

.NEAR TERM /THROUGH TONIGHT/...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK TRAPPED BELOW A
MODERATELY STRONG SUBSIDENCE INVERSION /BASED AT AROUND 2-3KFT
AGL/ WILL PERSIST ACROSS MUCH OF NORTHERN AND WESTERN PENNSYLVANIA
LATE TODAY INTO SATURDAY...WHILE PARTIAL CLEARING OCCURS ACROSS
THE LOWER SUSQ VALLEY AND SURROUNDING AREAS.

TEMPS WILL REMAIN STEADY THROUGH LATE THIS AFTERNOON UNDER THE
10-15 KT NWRLY FLOW. READINGS WILL VARY FROM THE MID TO UPPER 20S
ACROSS THE NORTHERN AND WESTERN MOUNTAINS...TO THE LOWER 40S IN
THE SOUTHEAST.

A WEAK SFC RIDGE WILL MOVE TO NEAR THE PENN/OHIO BORDER BY 12Z
SATURDAY...BUT THE WEAK WESTERLY ISENTROPIC LIFT ALONG THE 285K
THETA SFC...AND SOME SHALLOW MOISTURE BEING ADVECTED SWD INTO THE
NRN MTNS OF PENN FROM LAKE ONTARIO...WILL MAINTAIN MOSTLY CLOUDY
TO CLOUDY SKIES. LITTLE MORE THAN A FEW FLURRIES OR SPOTTY -FZDZ
WILL FALL FROM THIS THIN CLOUD LAYER ACROSS THE HIGHER TERRAIN OF
THE LAURELS AND INVOF KBFD.

AFTER A PTLY CLOUDY LATE AFTERNOON AND EVENING IN THE SE PART OF
THE CWA...A BKN LAYER OF STRATO CU IS EXPECTED TO DRIFT SE /OR
FORM/ ACROSS THE REGION OVERNIGHT.

DUE TO THE NW-SE GRADIENT OF DECREASING CLOUDS...LOW TEMPS AT
DAYBREAK SAT WILL BE IN A RATHER TIGHT RANGE...FROM THE UPPER
TEENS TO LOWER 20S ACROSS THE MOUNTAINS...TO THE LOWER 20S IN THE
SE

&&

.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
A RIDGE OF HIGH PRESSURE...LIGHTER WIND...AND ASSOC DRIER AIR
MASS WILL BUILD EAST ACROSS THE STATE SATURDAY...PROVIDING THE
AREA WITH FAIR WEATHER.

HIGH RES MODEL DATA CONTINUES TO PAINT A MOSTLY CLOUDY PICTURE FOR
MUCH OF THE REGION SATURDAY INTO SATURDAY NIGHT...THOUGH PERIODS
OF SUNSHINE ARE LIKELY THROUGHOUT THE CENTRAL RIDGE AND VALLEY
REGION...AND SUSQUEHANNA RIVER VALLEY.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS OVER THE LOWER/THIN STRATO CU
CLOUD DECK PRESENT ACROSS THE REGION SATURDAY. ALL 12Z OPERATIONAL
MODEL DATA CONTINUES TO SUPPORT A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS NEAR 30 ACROSS THE MTNS...AND MID TO UPPER 30S IN
THE SE.

MOSTLY CLOUDY SKIES WITH LIGHT WIND SAT NIGHT WILL YIELD LOWS IN
THE LOWER 20S ACROSS THE MTNS...AND GENERALLY THE MID 20S
ELSEWHERE.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGH PRESSURE WILL SHIFT SLOWLY EASTWARD FROM THE GREAT LAKES
INTO NORTHERN NEW ENGLAND BY 12Z MONDAY. A MOISTURE-STARVED NRN
STREAM SHORTWAVE SHOULD PRODUCE A PERIOD OF CLOUDINESS SAT
NIGHT...BUT LIKELY NOT PRODUCE ANY PRECIP. LATEST MDL SOUNDINGS
POINT TOWARD A RELATIVELY BRIGHT SUNDAY IN THE WAKE OF THIS
FEATURE WITH NEAR SEASONAL TEMPS. SPLIT FLOW REGIME ACROSS THE
LOWER 48 WILL TRANSITION TO A HIGHLY AMPLIFIED PATTERN BY EARLY
NEXT WEEK ACROSS THE LOWER 48...WITH A DEEP NEGATIVELY TILTED
TROUGH EVOLVING OVER THE EASTERN 1/3RD OF THE CONUS.

THE MODELS SEEM TO BE FORMING A CONSENSUS ON THE PESKY LOW
THAT REFUSES TO BE WELL FORECAST...LIFTING IT SLOWLY FROM FL
PANHANDLE NNEWD JUST OFF THE EAST COAST SUN-MON ALONG A LOW LEVEL
BAROCLINIC ZONE THAT MAY NOT BUDGE PAST THE GULF STREAM AS THE
FLOW ALOFT TURNS SOUTHWESTERLY/PARALLEL TO THE COASTAL FRONT.
INCREASED POPS FOR MONDAY OVER THE SE BASED ON MULTI-MODEL/WPC
BLEND. COMPLEX SFC PATTERN WITH SOME HINTS AT LOW LEVEL CAD ALONG
WITH WAA ALOFT VIA SLY FLOW COULD MAKE FOR A MESSY MIXED PTYPE
TRANSITION.

AN INTENSE TRIPLE POINT SYSTEM DEVELOPING ON DEC 23-24 WILL
LIKELY STEAL THE HEADLINES GIVEN ITS TIMING AND LARGE PORTION OF
REAL ESTATE THAT WILL BE AFFECTED. WHILE THE DETAILS REMAIN
UNCLEAR AT THIS POINT...TEMPERATURES SHOULD BE WARM ENOUGH TO
SUPPORT RAIN ON THE FRONT SIDE OF THE SYSTEM BEFORE BRISK WNW
WINDS DRIVE STRONG CAA EAST OF THE APPALACHIANS. THE TIMING OF THE
COLD/OCCLUDED FRONT WILL BE KEY FOR PRECIPITATION TRANSITION FROM
RAIN TO SNOW SHOWERS. AS THE SYSTEM SPINS UP INTO EASTERN
CANADA...THE STRONG CAA CIRCULATING THROUGH THE GREAT LAKES AND OH
VLY SHOULD LEAD TO LAKE EFFECT/UPSLOPE/WRAP AROUND SNOW SHOWERS
OVER THE WESTERN ALLEGHENIES BY CHRISTMAS DAY. A PERIOD OF STRONG
GUSTY WINDS ARE HIGHLY PROBABLE AS THE DYNAMIC SYSTEM INTENSIFIES
SHIFTING NWWD FROM NEW ENGLAND INTO ONTARIO/QUEBEC.

THE TAKE HOME MESSAGE IS THAT A VOLATILE PERIOD OF WEATHER WILL
IMPACT THE AREA THROUGH CHRISTMAS DAY WITH POTENTIAL WIND...RAIN
AND SNOW IMPACTS ALL ON THE TABLE. STAY TUNED.

&&

.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
LLVL NWRLY FLOW AND OROGRAPHIC FORCING OF A SHALLOW MOIST LAYER
WILL CONTINUE TO PRODUCE PLENTY OF CLOUDS ACROSS THE NW 1/2 TO
2/3RDS OF THE STATE WITH MAINLY MVFR BKN-OVC CIGS THROUGH
TONIGHT. KJST AND KBFD MAY TEETER ON THE UPPER END OF IFR FOR A
FEW HOURS LATER TONIGHT /AFTER 06Z/. IN CONTRAST...THE SE PENN
AIRFIELDS SUCH AS KMDT...KTHV AND KLNS WILL SEE MAINLY VFR...WITH
SKY CONDITIONS VARYING SCT-BKN030-040.

NORTHWEST WINDS OF 10-15 KTS WITH HIGHER GUSTS WILL DECREASE TO 8
KTS OR LESS LATER TONIGHT AND SATURDAY.

HIGH PRESSURE BUILDS EAST ACROSS PENN SATURDAY...WITH BKN-OVC CIGS
VARYING BETWEEN MVFR OVER THE HIGHER TERRAIN OF THE NORTH AND
WEST...TO SCT-BKN VFR IN THE VALLEYS.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYINGY INTENSITY...LEADING
TO MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...FITZGERALD/STEINBUGL
AVIATION...LAMBERT




000
FXUS61 KCTP 192007
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
307 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER THE WESTERN GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND...BRINGING DRY WEATHER WITH
LIGHTER WIND. A DEEP UPPER TROUGH AND ASSOCIATED SFC LOW WILL LIFT
NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE OF NEXT WEEK
LIKELY BRINGING US RAIN AND WIND FOR CHRISTMAS EVE...THEN BLUSTERY
AND COLDER CONDITIONS FOR CHRISTMAS DAY WITH SCATTERED SNOW
SHOWERS.

&&

.NEAR TERM /THROUGH TONIGHT/...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK TRAPPED BELOW A
MODERATELY STRONG SUBSIDENCE INVERSION /BASED AT AROUND 2-3KFT
AGL/ WILL PERSIST ACROSS MUCH OF NORTHERN AND WESTERN PENNSYLVANIA
LATE TODAY INTO SATURDAY...WHILE PARTIAL CLEARING OCCURS ACROSS
THE LOWER SUSQ VALLEY AND SURROUNDING AREAS.

TEMPS WILL REMAIN STEADY THROUGH LATE THIS AFTERNOON UNDER THE
10-15 KT NWRLY FLOW. READINGS WILL VARY FROM THE MID TO UPPER 20S
ACROSS THE NORTHERN AND WESTERN MOUNTAINS...TO THE LOWER 40S IN
THE SOUTHEAST.

A WEAK SFC RIDGE WILL MOVE TO NEAR THE PENN/OHIO BORDER BY 12Z
SATURDAY...BUT THE WEAK WESTERLY ISENTROPIC LIFT ALONG THE 285K
THETA SFC...AND SOME SHALLOW MOISTURE BEING ADVECTED SWD INTO THE
NRN MTNS OF PENN FROM LAKE ONTARIO...WILL MAINTAIN MOSTLY CLOUDY
TO CLOUDY SKIES. LITTLE MORE THAN A FEW FLURRIES OR SPOTTY -FZDZ
WILL FALL FROM THIS THIN CLOUD LAYER ACROSS THE HIGHER TERRAIN OF
THE LAURELS AND INVOF KBFD.

AFTER A PTLY CLOUDY LATE AFTERNOON AND EVENING IN THE SE PART OF
THE CWA...A BKN LAYER OF STRATO CU IS EXPECTED TO DRIFT SE /OR
FORM/ ACROSS THE REGION OVERNIGHT.

DUE TO THE NW-SE GRADIENT OF DECREASING CLOUDS...LOW TEMPS AT
DAYBREAK SAT WILL BE IN A RATHER TIGHT RANGE...FROM THE UPPER
TEENS TO LOWER 20S ACROSS THE MOUNTAINS...TO THE LOWER 20S IN THE
SE

&&

.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
A RIDGE OF HIGH PRESSURE...LIGHTER WIND...AND ASSOC DRIER AIR
MASS WILL BUILD EAST ACROSS THE STATE SATURDAY...PROVIDING THE
AREA WITH FAIR WEATHER.

HIGH RES MODEL DATA CONTINUES TO PAINT A MOSTLY CLOUDY PICTURE FOR
MUCH OF THE REGION SATURDAY INTO SATURDAY NIGHT...THOUGH PERIODS
OF SUNSHINE ARE LIKELY THROUGHOUT THE CENTRAL RIDGE AND VALLEY
REGION...AND SUSQUEHANNA RIVER VALLEY.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS OVER THE LOWER/THIN STRATO CU
CLOUD DECK PRESENT ACROSS THE REGION SATURDAY. ALL 12Z OPERATIONAL
MODEL DATA CONTINUES TO SUPPORT A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS NEAR 30 ACROSS THE MTNS...AND MID TO UPPER 30S IN
THE SE.

MOSTLY CLOUDY SKIES WITH LIGHT WIND SAT NIGHT WILL YIELD LOWS IN
THE LOWER 20S ACROSS THE MTNS...AND GENERALLY THE MID 20S
ELSEWHERE.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGH PRESSURE WILL SHIFT SLOWLY EASTWARD FROM THE GREAT LAKES
INTO NORTHERN NEW ENGLAND BY 12Z MONDAY. A MOISTURE-STARVED NRN
STREAM SHORTWAVE SHOULD PRODUCE A PERIOD OF CLOUDINESS SAT
NIGHT...BUT LIKELY NOT PRODUCE ANY PRECIP. LATEST MDL SOUNDINGS
POINT TOWARD A RELATIVELY BRIGHT SUNDAY IN THE WAKE OF THIS
FEATURE WITH NEAR SEASONAL TEMPS. SPLIT FLOW REGIME ACROSS THE
LOWER 48 WILL TRANSITION TO A HIGHLY AMPLIFIED PATTERN BY EARLY
NEXT WEEK ACROSS THE LOWER 48...WITH A DEEP NEGATIVELY TILTED
TROUGH EVOLVING OVER THE EASTERN 1/3RD OF THE CONUS.

THE MODELS SEEM TO BE FORMING A CONSENSUS ON THE PESKY LOW
THAT REFUSES TO BE WELL FORECAST...LIFTING IT SLOWLY FROM FL
PANHANDLE NNEWD JUST OFF THE EAST COAST SUN-MON ALONG A LOW LEVEL
BAROCLINIC ZONE THAT MAY NOT BUDGE PAST THE GULF STREAM AS THE
FLOW ALOFT TURNS SOUTHWESTERLY/PARALLEL TO THE COASTAL FRONT.
INCREASED POPS FOR MONDAY OVER THE SE BASED ON MULTI-MODEL/WPC
BLEND. COMPLEX SFC PATTERN WITH SOME HINTS AT LOW LEVEL CAD ALONG
WITH WAA ALOFT VIA SLY FLOW COULD MAKE FOR A MESSY MIXED PTYPE
TRANSITION.

AN INTENSE TRIPLE POINT SYSTEM DEVELOPING ON DEC 23-24 WILL
LIKELY STEAL THE HEADLINES GIVEN ITS TIMING AND LARGE PORTION OF
REAL ESTATE THAT WILL BE AFFECTED. WHILE THE DETAILS REMAIN
UNCLEAR AT THIS POINT...TEMPERATURES SHOULD BE WARM ENOUGH TO
SUPPORT RAIN ON THE FRONT SIDE OF THE SYSTEM BEFORE BRISK WNW
WINDS DRIVE STRONG CAA EAST OF THE APPALACHIANS. THE TIMING OF THE
COLD/OCCLUDED FRONT WILL BE KEY FOR PRECIPITATION TRANSITION FROM
RAIN TO SNOW SHOWERS. AS THE SYSTEM SPINS UP INTO EASTERN
CANADA...THE STRONG CAA CIRCULATING THROUGH THE GREAT LAKES AND OH
VLY SHOULD LEAD TO LAKE EFFECT/UPSLOPE/WRAP AROUND SNOW SHOWERS
OVER THE WESTERN ALLEGHENIES BY CHRISTMAS DAY. A PERIOD OF STRONG
GUSTY WINDS ARE HIGHLY PROBABLE AS THE DYNAMIC SYSTEM INTENSIFIES
SHIFTING NWWD FROM NEW ENGLAND INTO ONTARIO/QUEBEC.

THE TAKE HOME MESSAGE IS THAT A VOLATILE PERIOD OF WEATHER WILL
IMPACT THE AREA THROUGH CHRISTMAS DAY WITH POTENTIAL WIND...RAIN
AND SNOW IMPACTS ALL ON THE TABLE. STAY TUNED.

&&

.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
LLVL NWRLY FLOW AND OROGRAPHIC FORCING OF A SHALLOW MOIST LAYER
WILL CONTINUE TO PRODUCE PLENTY OF CLOUDS ACROSS THE NW 1/2 TO
2/3RDS OF THE STATE WITH MAINLY MVFR BKN-OVC CIGS THROUGH
TONIGHT. KJST AND KBFD MAY TEETER ON THE UPPER END OF IFR FOR A
FEW HOURS LATER TONIGHT /AFTER 06Z/. IN CONTRAST...THE SE PENN
AIRFIELDS SUCH AS KMDT...KTHV AND KLNS WILL SEE MAINLY VFR...WITH
SKY CONDITIONS VARYING SCT-BKN030-040.

NORTHWEST WINDS OF 10-15 KTS WITH HIGHER GUSTS WILL DECREASE TO 8
KTS OR LESS LATER TONIGHT AND SATURDAY.

HIGH PRESSURE BUILDS EAST ACROSS PENN SATURDAY...WITH BKN-OVC CIGS
VARYING BETWEEN MVFR OVER THE HIGHER TERRAIN OF THE NORTH AND
WEST...TO SCT-BKN VFR IN THE VALLEYS.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYINGY INTENSITY...LEADING
TO MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...FITZGERALD/STEINBUGL
AVIATION...LAMBERT




000
FXUS61 KCTP 192007
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
307 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER THE WESTERN GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND...BRINGING DRY WEATHER WITH
LIGHTER WIND. A DEEP UPPER TROUGH AND ASSOCIATED SFC LOW WILL LIFT
NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE OF NEXT WEEK
LIKELY BRINGING US RAIN AND WIND FOR CHRISTMAS EVE...THEN BLUSTERY
AND COLDER CONDITIONS FOR CHRISTMAS DAY WITH SCATTERED SNOW
SHOWERS.

&&

.NEAR TERM /THROUGH TONIGHT/...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK TRAPPED BELOW A
MODERATELY STRONG SUBSIDENCE INVERSION /BASED AT AROUND 2-3KFT
AGL/ WILL PERSIST ACROSS MUCH OF NORTHERN AND WESTERN PENNSYLVANIA
LATE TODAY INTO SATURDAY...WHILE PARTIAL CLEARING OCCURS ACROSS
THE LOWER SUSQ VALLEY AND SURROUNDING AREAS.

TEMPS WILL REMAIN STEADY THROUGH LATE THIS AFTERNOON UNDER THE
10-15 KT NWRLY FLOW. READINGS WILL VARY FROM THE MID TO UPPER 20S
ACROSS THE NORTHERN AND WESTERN MOUNTAINS...TO THE LOWER 40S IN
THE SOUTHEAST.

A WEAK SFC RIDGE WILL MOVE TO NEAR THE PENN/OHIO BORDER BY 12Z
SATURDAY...BUT THE WEAK WESTERLY ISENTROPIC LIFT ALONG THE 285K
THETA SFC...AND SOME SHALLOW MOISTURE BEING ADVECTED SWD INTO THE
NRN MTNS OF PENN FROM LAKE ONTARIO...WILL MAINTAIN MOSTLY CLOUDY
TO CLOUDY SKIES. LITTLE MORE THAN A FEW FLURRIES OR SPOTTY -FZDZ
WILL FALL FROM THIS THIN CLOUD LAYER ACROSS THE HIGHER TERRAIN OF
THE LAURELS AND INVOF KBFD.

AFTER A PTLY CLOUDY LATE AFTERNOON AND EVENING IN THE SE PART OF
THE CWA...A BKN LAYER OF STRATO CU IS EXPECTED TO DRIFT SE /OR
FORM/ ACROSS THE REGION OVERNIGHT.

DUE TO THE NW-SE GRADIENT OF DECREASING CLOUDS...LOW TEMPS AT
DAYBREAK SAT WILL BE IN A RATHER TIGHT RANGE...FROM THE UPPER
TEENS TO LOWER 20S ACROSS THE MOUNTAINS...TO THE LOWER 20S IN THE
SE

&&

.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
A RIDGE OF HIGH PRESSURE...LIGHTER WIND...AND ASSOC DRIER AIR
MASS WILL BUILD EAST ACROSS THE STATE SATURDAY...PROVIDING THE
AREA WITH FAIR WEATHER.

HIGH RES MODEL DATA CONTINUES TO PAINT A MOSTLY CLOUDY PICTURE FOR
MUCH OF THE REGION SATURDAY INTO SATURDAY NIGHT...THOUGH PERIODS
OF SUNSHINE ARE LIKELY THROUGHOUT THE CENTRAL RIDGE AND VALLEY
REGION...AND SUSQUEHANNA RIVER VALLEY.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS OVER THE LOWER/THIN STRATO CU
CLOUD DECK PRESENT ACROSS THE REGION SATURDAY. ALL 12Z OPERATIONAL
MODEL DATA CONTINUES TO SUPPORT A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS NEAR 30 ACROSS THE MTNS...AND MID TO UPPER 30S IN
THE SE.

MOSTLY CLOUDY SKIES WITH LIGHT WIND SAT NIGHT WILL YIELD LOWS IN
THE LOWER 20S ACROSS THE MTNS...AND GENERALLY THE MID 20S
ELSEWHERE.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGH PRESSURE WILL SHIFT SLOWLY EASTWARD FROM THE GREAT LAKES
INTO NORTHERN NEW ENGLAND BY 12Z MONDAY. A MOISTURE-STARVED NRN
STREAM SHORTWAVE SHOULD PRODUCE A PERIOD OF CLOUDINESS SAT
NIGHT...BUT LIKELY NOT PRODUCE ANY PRECIP. LATEST MDL SOUNDINGS
POINT TOWARD A RELATIVELY BRIGHT SUNDAY IN THE WAKE OF THIS
FEATURE WITH NEAR SEASONAL TEMPS. SPLIT FLOW REGIME ACROSS THE
LOWER 48 WILL TRANSITION TO A HIGHLY AMPLIFIED PATTERN BY EARLY
NEXT WEEK ACROSS THE LOWER 48...WITH A DEEP NEGATIVELY TILTED
TROUGH EVOLVING OVER THE EASTERN 1/3RD OF THE CONUS.

THE MODELS SEEM TO BE FORMING A CONSENSUS ON THE PESKY LOW
THAT REFUSES TO BE WELL FORECAST...LIFTING IT SLOWLY FROM FL
PANHANDLE NNEWD JUST OFF THE EAST COAST SUN-MON ALONG A LOW LEVEL
BAROCLINIC ZONE THAT MAY NOT BUDGE PAST THE GULF STREAM AS THE
FLOW ALOFT TURNS SOUTHWESTERLY/PARALLEL TO THE COASTAL FRONT.
INCREASED POPS FOR MONDAY OVER THE SE BASED ON MULTI-MODEL/WPC
BLEND. COMPLEX SFC PATTERN WITH SOME HINTS AT LOW LEVEL CAD ALONG
WITH WAA ALOFT VIA SLY FLOW COULD MAKE FOR A MESSY MIXED PTYPE
TRANSITION.

AN INTENSE TRIPLE POINT SYSTEM DEVELOPING ON DEC 23-24 WILL
LIKELY STEAL THE HEADLINES GIVEN ITS TIMING AND LARGE PORTION OF
REAL ESTATE THAT WILL BE AFFECTED. WHILE THE DETAILS REMAIN
UNCLEAR AT THIS POINT...TEMPERATURES SHOULD BE WARM ENOUGH TO
SUPPORT RAIN ON THE FRONT SIDE OF THE SYSTEM BEFORE BRISK WNW
WINDS DRIVE STRONG CAA EAST OF THE APPALACHIANS. THE TIMING OF THE
COLD/OCCLUDED FRONT WILL BE KEY FOR PRECIPITATION TRANSITION FROM
RAIN TO SNOW SHOWERS. AS THE SYSTEM SPINS UP INTO EASTERN
CANADA...THE STRONG CAA CIRCULATING THROUGH THE GREAT LAKES AND OH
VLY SHOULD LEAD TO LAKE EFFECT/UPSLOPE/WRAP AROUND SNOW SHOWERS
OVER THE WESTERN ALLEGHENIES BY CHRISTMAS DAY. A PERIOD OF STRONG
GUSTY WINDS ARE HIGHLY PROBABLE AS THE DYNAMIC SYSTEM INTENSIFIES
SHIFTING NWWD FROM NEW ENGLAND INTO ONTARIO/QUEBEC.

THE TAKE HOME MESSAGE IS THAT A VOLATILE PERIOD OF WEATHER WILL
IMPACT THE AREA THROUGH CHRISTMAS DAY WITH POTENTIAL WIND...RAIN
AND SNOW IMPACTS ALL ON THE TABLE. STAY TUNED.

&&

.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
LLVL NWRLY FLOW AND OROGRAPHIC FORCING OF A SHALLOW MOIST LAYER
WILL CONTINUE TO PRODUCE PLENTY OF CLOUDS ACROSS THE NW 1/2 TO
2/3RDS OF THE STATE WITH MAINLY MVFR BKN-OVC CIGS THROUGH
TONIGHT. KJST AND KBFD MAY TEETER ON THE UPPER END OF IFR FOR A
FEW HOURS LATER TONIGHT /AFTER 06Z/. IN CONTRAST...THE SE PENN
AIRFIELDS SUCH AS KMDT...KTHV AND KLNS WILL SEE MAINLY VFR...WITH
SKY CONDITIONS VARYING SCT-BKN030-040.

NORTHWEST WINDS OF 10-15 KTS WITH HIGHER GUSTS WILL DECREASE TO 8
KTS OR LESS LATER TONIGHT AND SATURDAY.

HIGH PRESSURE BUILDS EAST ACROSS PENN SATURDAY...WITH BKN-OVC CIGS
VARYING BETWEEN MVFR OVER THE HIGHER TERRAIN OF THE NORTH AND
WEST...TO SCT-BKN VFR IN THE VALLEYS.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYINGY INTENSITY...LEADING
TO MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...FITZGERALD/STEINBUGL
AVIATION...LAMBERT




000
FXUS61 KCTP 192007
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
307 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER THE WESTERN GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND...BRINGING DRY WEATHER WITH
LIGHTER WIND. A DEEP UPPER TROUGH AND ASSOCIATED SFC LOW WILL LIFT
NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE OF NEXT WEEK
LIKELY BRINGING US RAIN AND WIND FOR CHRISTMAS EVE...THEN BLUSTERY
AND COLDER CONDITIONS FOR CHRISTMAS DAY WITH SCATTERED SNOW
SHOWERS.

&&

.NEAR TERM /THROUGH TONIGHT/...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK TRAPPED BELOW A
MODERATELY STRONG SUBSIDENCE INVERSION /BASED AT AROUND 2-3KFT
AGL/ WILL PERSIST ACROSS MUCH OF NORTHERN AND WESTERN PENNSYLVANIA
LATE TODAY INTO SATURDAY...WHILE PARTIAL CLEARING OCCURS ACROSS
THE LOWER SUSQ VALLEY AND SURROUNDING AREAS.

TEMPS WILL REMAIN STEADY THROUGH LATE THIS AFTERNOON UNDER THE
10-15 KT NWRLY FLOW. READINGS WILL VARY FROM THE MID TO UPPER 20S
ACROSS THE NORTHERN AND WESTERN MOUNTAINS...TO THE LOWER 40S IN
THE SOUTHEAST.

A WEAK SFC RIDGE WILL MOVE TO NEAR THE PENN/OHIO BORDER BY 12Z
SATURDAY...BUT THE WEAK WESTERLY ISENTROPIC LIFT ALONG THE 285K
THETA SFC...AND SOME SHALLOW MOISTURE BEING ADVECTED SWD INTO THE
NRN MTNS OF PENN FROM LAKE ONTARIO...WILL MAINTAIN MOSTLY CLOUDY
TO CLOUDY SKIES. LITTLE MORE THAN A FEW FLURRIES OR SPOTTY -FZDZ
WILL FALL FROM THIS THIN CLOUD LAYER ACROSS THE HIGHER TERRAIN OF
THE LAURELS AND INVOF KBFD.

AFTER A PTLY CLOUDY LATE AFTERNOON AND EVENING IN THE SE PART OF
THE CWA...A BKN LAYER OF STRATO CU IS EXPECTED TO DRIFT SE /OR
FORM/ ACROSS THE REGION OVERNIGHT.

DUE TO THE NW-SE GRADIENT OF DECREASING CLOUDS...LOW TEMPS AT
DAYBREAK SAT WILL BE IN A RATHER TIGHT RANGE...FROM THE UPPER
TEENS TO LOWER 20S ACROSS THE MOUNTAINS...TO THE LOWER 20S IN THE
SE

&&

.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
A RIDGE OF HIGH PRESSURE...LIGHTER WIND...AND ASSOC DRIER AIR
MASS WILL BUILD EAST ACROSS THE STATE SATURDAY...PROVIDING THE
AREA WITH FAIR WEATHER.

HIGH RES MODEL DATA CONTINUES TO PAINT A MOSTLY CLOUDY PICTURE FOR
MUCH OF THE REGION SATURDAY INTO SATURDAY NIGHT...THOUGH PERIODS
OF SUNSHINE ARE LIKELY THROUGHOUT THE CENTRAL RIDGE AND VALLEY
REGION...AND SUSQUEHANNA RIVER VALLEY.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS OVER THE LOWER/THIN STRATO CU
CLOUD DECK PRESENT ACROSS THE REGION SATURDAY. ALL 12Z OPERATIONAL
MODEL DATA CONTINUES TO SUPPORT A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS NEAR 30 ACROSS THE MTNS...AND MID TO UPPER 30S IN
THE SE.

MOSTLY CLOUDY SKIES WITH LIGHT WIND SAT NIGHT WILL YIELD LOWS IN
THE LOWER 20S ACROSS THE MTNS...AND GENERALLY THE MID 20S
ELSEWHERE.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGH PRESSURE WILL SHIFT SLOWLY EASTWARD FROM THE GREAT LAKES
INTO NORTHERN NEW ENGLAND BY 12Z MONDAY. A MOISTURE-STARVED NRN
STREAM SHORTWAVE SHOULD PRODUCE A PERIOD OF CLOUDINESS SAT
NIGHT...BUT LIKELY NOT PRODUCE ANY PRECIP. LATEST MDL SOUNDINGS
POINT TOWARD A RELATIVELY BRIGHT SUNDAY IN THE WAKE OF THIS
FEATURE WITH NEAR SEASONAL TEMPS. SPLIT FLOW REGIME ACROSS THE
LOWER 48 WILL TRANSITION TO A HIGHLY AMPLIFIED PATTERN BY EARLY
NEXT WEEK ACROSS THE LOWER 48...WITH A DEEP NEGATIVELY TILTED
TROUGH EVOLVING OVER THE EASTERN 1/3RD OF THE CONUS.

THE MODELS SEEM TO BE FORMING A CONSENSUS ON THE PESKY LOW
THAT REFUSES TO BE WELL FORECAST...LIFTING IT SLOWLY FROM FL
PANHANDLE NNEWD JUST OFF THE EAST COAST SUN-MON ALONG A LOW LEVEL
BAROCLINIC ZONE THAT MAY NOT BUDGE PAST THE GULF STREAM AS THE
FLOW ALOFT TURNS SOUTHWESTERLY/PARALLEL TO THE COASTAL FRONT.
INCREASED POPS FOR MONDAY OVER THE SE BASED ON MULTI-MODEL/WPC
BLEND. COMPLEX SFC PATTERN WITH SOME HINTS AT LOW LEVEL CAD ALONG
WITH WAA ALOFT VIA SLY FLOW COULD MAKE FOR A MESSY MIXED PTYPE
TRANSITION.

AN INTENSE TRIPLE POINT SYSTEM DEVELOPING ON DEC 23-24 WILL
LIKELY STEAL THE HEADLINES GIVEN ITS TIMING AND LARGE PORTION OF
REAL ESTATE THAT WILL BE AFFECTED. WHILE THE DETAILS REMAIN
UNCLEAR AT THIS POINT...TEMPERATURES SHOULD BE WARM ENOUGH TO
SUPPORT RAIN ON THE FRONT SIDE OF THE SYSTEM BEFORE BRISK WNW
WINDS DRIVE STRONG CAA EAST OF THE APPALACHIANS. THE TIMING OF THE
COLD/OCCLUDED FRONT WILL BE KEY FOR PRECIPITATION TRANSITION FROM
RAIN TO SNOW SHOWERS. AS THE SYSTEM SPINS UP INTO EASTERN
CANADA...THE STRONG CAA CIRCULATING THROUGH THE GREAT LAKES AND OH
VLY SHOULD LEAD TO LAKE EFFECT/UPSLOPE/WRAP AROUND SNOW SHOWERS
OVER THE WESTERN ALLEGHENIES BY CHRISTMAS DAY. A PERIOD OF STRONG
GUSTY WINDS ARE HIGHLY PROBABLE AS THE DYNAMIC SYSTEM INTENSIFIES
SHIFTING NWWD FROM NEW ENGLAND INTO ONTARIO/QUEBEC.

THE TAKE HOME MESSAGE IS THAT A VOLATILE PERIOD OF WEATHER WILL
IMPACT THE AREA THROUGH CHRISTMAS DAY WITH POTENTIAL WIND...RAIN
AND SNOW IMPACTS ALL ON THE TABLE. STAY TUNED.

&&

.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
LLVL NWRLY FLOW AND OROGRAPHIC FORCING OF A SHALLOW MOIST LAYER
WILL CONTINUE TO PRODUCE PLENTY OF CLOUDS ACROSS THE NW 1/2 TO
2/3RDS OF THE STATE WITH MAINLY MVFR BKN-OVC CIGS THROUGH
TONIGHT. KJST AND KBFD MAY TEETER ON THE UPPER END OF IFR FOR A
FEW HOURS LATER TONIGHT /AFTER 06Z/. IN CONTRAST...THE SE PENN
AIRFIELDS SUCH AS KMDT...KTHV AND KLNS WILL SEE MAINLY VFR...WITH
SKY CONDITIONS VARYING SCT-BKN030-040.

NORTHWEST WINDS OF 10-15 KTS WITH HIGHER GUSTS WILL DECREASE TO 8
KTS OR LESS LATER TONIGHT AND SATURDAY.

HIGH PRESSURE BUILDS EAST ACROSS PENN SATURDAY...WITH BKN-OVC CIGS
VARYING BETWEEN MVFR OVER THE HIGHER TERRAIN OF THE NORTH AND
WEST...TO SCT-BKN VFR IN THE VALLEYS.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYINGY INTENSITY...LEADING
TO MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...FITZGERALD/STEINBUGL
AVIATION...LAMBERT




000
FXUS61 KCTP 192007
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
307 PM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER THE WESTERN GREAT LAKES WILL SLIDE
EAST ACROSS PENNSYLVANIA THIS WEEKEND...BRINGING DRY WEATHER WITH
LIGHTER WIND. A DEEP UPPER TROUGH AND ASSOCIATED SFC LOW WILL LIFT
NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE OF NEXT WEEK
LIKELY BRINGING US RAIN AND WIND FOR CHRISTMAS EVE...THEN BLUSTERY
AND COLDER CONDITIONS FOR CHRISTMAS DAY WITH SCATTERED SNOW
SHOWERS.

&&

.NEAR TERM /THROUGH TONIGHT/...
STUBBORN...ALBEIT SHALLOW STRATO CU CLOUD DECK TRAPPED BELOW A
MODERATELY STRONG SUBSIDENCE INVERSION /BASED AT AROUND 2-3KFT
AGL/ WILL PERSIST ACROSS MUCH OF NORTHERN AND WESTERN PENNSYLVANIA
LATE TODAY INTO SATURDAY...WHILE PARTIAL CLEARING OCCURS ACROSS
THE LOWER SUSQ VALLEY AND SURROUNDING AREAS.

TEMPS WILL REMAIN STEADY THROUGH LATE THIS AFTERNOON UNDER THE
10-15 KT NWRLY FLOW. READINGS WILL VARY FROM THE MID TO UPPER 20S
ACROSS THE NORTHERN AND WESTERN MOUNTAINS...TO THE LOWER 40S IN
THE SOUTHEAST.

A WEAK SFC RIDGE WILL MOVE TO NEAR THE PENN/OHIO BORDER BY 12Z
SATURDAY...BUT THE WEAK WESTERLY ISENTROPIC LIFT ALONG THE 285K
THETA SFC...AND SOME SHALLOW MOISTURE BEING ADVECTED SWD INTO THE
NRN MTNS OF PENN FROM LAKE ONTARIO...WILL MAINTAIN MOSTLY CLOUDY
TO CLOUDY SKIES. LITTLE MORE THAN A FEW FLURRIES OR SPOTTY -FZDZ
WILL FALL FROM THIS THIN CLOUD LAYER ACROSS THE HIGHER TERRAIN OF
THE LAURELS AND INVOF KBFD.

AFTER A PTLY CLOUDY LATE AFTERNOON AND EVENING IN THE SE PART OF
THE CWA...A BKN LAYER OF STRATO CU IS EXPECTED TO DRIFT SE /OR
FORM/ ACROSS THE REGION OVERNIGHT.

DUE TO THE NW-SE GRADIENT OF DECREASING CLOUDS...LOW TEMPS AT
DAYBREAK SAT WILL BE IN A RATHER TIGHT RANGE...FROM THE UPPER
TEENS TO LOWER 20S ACROSS THE MOUNTAINS...TO THE LOWER 20S IN THE
SE

&&

.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
A RIDGE OF HIGH PRESSURE...LIGHTER WIND...AND ASSOC DRIER AIR
MASS WILL BUILD EAST ACROSS THE STATE SATURDAY...PROVIDING THE
AREA WITH FAIR WEATHER.

HIGH RES MODEL DATA CONTINUES TO PAINT A MOSTLY CLOUDY PICTURE FOR
MUCH OF THE REGION SATURDAY INTO SATURDAY NIGHT...THOUGH PERIODS
OF SUNSHINE ARE LIKELY THROUGHOUT THE CENTRAL RIDGE AND VALLEY
REGION...AND SUSQUEHANNA RIVER VALLEY.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS OVER THE LOWER/THIN STRATO CU
CLOUD DECK PRESENT ACROSS THE REGION SATURDAY. ALL 12Z OPERATIONAL
MODEL DATA CONTINUES TO SUPPORT A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS NEAR 30 ACROSS THE MTNS...AND MID TO UPPER 30S IN
THE SE.

MOSTLY CLOUDY SKIES WITH LIGHT WIND SAT NIGHT WILL YIELD LOWS IN
THE LOWER 20S ACROSS THE MTNS...AND GENERALLY THE MID 20S
ELSEWHERE.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGH PRESSURE WILL SHIFT SLOWLY EASTWARD FROM THE GREAT LAKES
INTO NORTHERN NEW ENGLAND BY 12Z MONDAY. A MOISTURE-STARVED NRN
STREAM SHORTWAVE SHOULD PRODUCE A PERIOD OF CLOUDINESS SAT
NIGHT...BUT LIKELY NOT PRODUCE ANY PRECIP. LATEST MDL SOUNDINGS
POINT TOWARD A RELATIVELY BRIGHT SUNDAY IN THE WAKE OF THIS
FEATURE WITH NEAR SEASONAL TEMPS. SPLIT FLOW REGIME ACROSS THE
LOWER 48 WILL TRANSITION TO A HIGHLY AMPLIFIED PATTERN BY EARLY
NEXT WEEK ACROSS THE LOWER 48...WITH A DEEP NEGATIVELY TILTED
TROUGH EVOLVING OVER THE EASTERN 1/3RD OF THE CONUS.

THE MODELS SEEM TO BE FORMING A CONSENSUS ON THE PESKY LOW
THAT REFUSES TO BE WELL FORECAST...LIFTING IT SLOWLY FROM FL
PANHANDLE NNEWD JUST OFF THE EAST COAST SUN-MON ALONG A LOW LEVEL
BAROCLINIC ZONE THAT MAY NOT BUDGE PAST THE GULF STREAM AS THE
FLOW ALOFT TURNS SOUTHWESTERLY/PARALLEL TO THE COASTAL FRONT.
INCREASED POPS FOR MONDAY OVER THE SE BASED ON MULTI-MODEL/WPC
BLEND. COMPLEX SFC PATTERN WITH SOME HINTS AT LOW LEVEL CAD ALONG
WITH WAA ALOFT VIA SLY FLOW COULD MAKE FOR A MESSY MIXED PTYPE
TRANSITION.

AN INTENSE TRIPLE POINT SYSTEM DEVELOPING ON DEC 23-24 WILL
LIKELY STEAL THE HEADLINES GIVEN ITS TIMING AND LARGE PORTION OF
REAL ESTATE THAT WILL BE AFFECTED. WHILE THE DETAILS REMAIN
UNCLEAR AT THIS POINT...TEMPERATURES SHOULD BE WARM ENOUGH TO
SUPPORT RAIN ON THE FRONT SIDE OF THE SYSTEM BEFORE BRISK WNW
WINDS DRIVE STRONG CAA EAST OF THE APPALACHIANS. THE TIMING OF THE
COLD/OCCLUDED FRONT WILL BE KEY FOR PRECIPITATION TRANSITION FROM
RAIN TO SNOW SHOWERS. AS THE SYSTEM SPINS UP INTO EASTERN
CANADA...THE STRONG CAA CIRCULATING THROUGH THE GREAT LAKES AND OH
VLY SHOULD LEAD TO LAKE EFFECT/UPSLOPE/WRAP AROUND SNOW SHOWERS
OVER THE WESTERN ALLEGHENIES BY CHRISTMAS DAY. A PERIOD OF STRONG
GUSTY WINDS ARE HIGHLY PROBABLE AS THE DYNAMIC SYSTEM INTENSIFIES
SHIFTING NWWD FROM NEW ENGLAND INTO ONTARIO/QUEBEC.

THE TAKE HOME MESSAGE IS THAT A VOLATILE PERIOD OF WEATHER WILL
IMPACT THE AREA THROUGH CHRISTMAS DAY WITH POTENTIAL WIND...RAIN
AND SNOW IMPACTS ALL ON THE TABLE. STAY TUNED.

&&

.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
LLVL NWRLY FLOW AND OROGRAPHIC FORCING OF A SHALLOW MOIST LAYER
WILL CONTINUE TO PRODUCE PLENTY OF CLOUDS ACROSS THE NW 1/2 TO
2/3RDS OF THE STATE WITH MAINLY MVFR BKN-OVC CIGS THROUGH
TONIGHT. KJST AND KBFD MAY TEETER ON THE UPPER END OF IFR FOR A
FEW HOURS LATER TONIGHT /AFTER 06Z/. IN CONTRAST...THE SE PENN
AIRFIELDS SUCH AS KMDT...KTHV AND KLNS WILL SEE MAINLY VFR...WITH
SKY CONDITIONS VARYING SCT-BKN030-040.

NORTHWEST WINDS OF 10-15 KTS WITH HIGHER GUSTS WILL DECREASE TO 8
KTS OR LESS LATER TONIGHT AND SATURDAY.

HIGH PRESSURE BUILDS EAST ACROSS PENN SATURDAY...WITH BKN-OVC CIGS
VARYING BETWEEN MVFR OVER THE HIGHER TERRAIN OF THE NORTH AND
WEST...TO SCT-BKN VFR IN THE VALLEYS.

OUTLOOK...

SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

WED...MILD WITH PERIODS OF RAIN OF VARYINGY INTENSITY...LEADING
TO MVFR TO IFR. ALSO...WINDY WITH LLWS.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...FITZGERALD/STEINBUGL
AVIATION...LAMBERT




000
FXUS61 KPBZ 191804
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
104 PM EST FRI DEC 19 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
SCATTERED FLURRIES MAY LAST FOR JUST A FEW MORE HOURS AS WEAKENING
NORTHWEST FLOW MAY PROVIDE FOR SOME LAKE ENHANCED FLURRIES IN THE
LINGERING LOW LEVEL MOISTURE. THE UPPER TROUGH WILL DEPART EAST
AND BE REPLACED BY RIDGING TONIGHT. MODEL PROFILES SUGGEST THAT
SOME MOISTURE WILL REMAIN TRAPPED UNDER THE BUILDING UPPER
RIDGE...PREVENTING US FROM CLEARING OUT THIS EVENING. THIS ISN`T
COMPLETELY CLEAR CUT...BUT WILL OPT TO KEEP MOSTLY CLOUDY WORDING
UNLESS SATELLITE OBSERVATIONS SHOW OTHERWISE. DID DROP TEMPS FOR THE REST OF
THE AFTERNOON AS CLOUD COVER SHOULD KEEP TEMPERATURES FROM WARMING
MUCH ABOVE CURRENT VALUES. LOWS TONIGHT WERE KEPT NEAR MET
GUIDANCE.

&&

.SHORT TERM /SATURDAY THROUGH MONDAY/...
HIGH PRESSURE WILL REIGN OVER THE FORECAST AREA THROUGH THE
WEEKEND. A WEAK OPEN WAVE TRIES TO SKIRT THE SRN EXTENT OF THE SFC
HIGH SAT AFTERNOON...BUT MODELS CONTINUE TO TREND IT FURTHER SOUTH
WELL OUT OF OUR REGION. AFTER LARGELY ZONAL FLOW ALOFT THROUGH
SUNDAY THE UPPER LEVEL PATTERN FAVORS SWRLY FLOW ON THE BACKSIDE
OF THE SFC HIGH. THIS WILL WORK TO DRIVE WARMER TEMPS INTO THE
FORECAST AREA WITH HIGHS DRIVING ABOVE AVERAGE HEADING INTO EARLY
NEXT WEEK.
TAX

&&

.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
WHILE IN GENERAL AGREEMENT ON DEEPENING UPPER LEVEL CLOSED LOW OVER
THE GREAT LAKES TUESDAY THROUGH THURSDAY WITH PERIODS OF RAIN INTO
WEDNESDAY UNTIL COLD FRONT WILL CHANGE PRECIP OVER TO SNOW SHOWERS
LATER WEDNESDAY AND THURSDAY. WINDS WILL BE ON THE INCREASE
THURSDAY AS SURFACE LOW WRAPS UP NORTH OF THE REGION. QPF ON THE
FRONT SIDE OF SYSTEM WILL BE NEAR AN INCH...WHICH SHOULD NOT
PRODUCE ANY SIGNIFICANT PROBLEMS. BACKLASH SNOW WEDNESDAY NIGHT
INTO THURSDAY WILL BE LIGHT WITH ONLY MINOR ACCUMULATIONS
EXPECTED. FLOW BEHIND COLD FRONT LOOKS TO STAY SOUTHWESTERLY WHICH
LOOKS TO LIMIT LAKE ENHANCED AMOUNTS ALONG I-80 AND THE RIDGES.
COLDER TEMPERATURES WILL THEN MODERATE FRIDAY AS MID LEVEL FLOW
QUICKLY BECOMES ZONAL.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
ISOLATED IFR SNOW SHOWERS AND FOG WILL END BY 20Z WITH GENERAL
MVFR EXPECTED THROUGH TONIGHT.


OUTLOOK.../SATURDAY FRIDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY AND WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$













000
FXUS61 KPBZ 191804
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
104 PM EST FRI DEC 19 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
SCATTERED FLURRIES MAY LAST FOR JUST A FEW MORE HOURS AS WEAKENING
NORTHWEST FLOW MAY PROVIDE FOR SOME LAKE ENHANCED FLURRIES IN THE
LINGERING LOW LEVEL MOISTURE. THE UPPER TROUGH WILL DEPART EAST
AND BE REPLACED BY RIDGING TONIGHT. MODEL PROFILES SUGGEST THAT
SOME MOISTURE WILL REMAIN TRAPPED UNDER THE BUILDING UPPER
RIDGE...PREVENTING US FROM CLEARING OUT THIS EVENING. THIS ISN`T
COMPLETELY CLEAR CUT...BUT WILL OPT TO KEEP MOSTLY CLOUDY WORDING
UNLESS SATELLITE OBSERVATIONS SHOW OTHERWISE. DID DROP TEMPS FOR THE REST OF
THE AFTERNOON AS CLOUD COVER SHOULD KEEP TEMPERATURES FROM WARMING
MUCH ABOVE CURRENT VALUES. LOWS TONIGHT WERE KEPT NEAR MET
GUIDANCE.

&&

.SHORT TERM /SATURDAY THROUGH MONDAY/...
HIGH PRESSURE WILL REIGN OVER THE FORECAST AREA THROUGH THE
WEEKEND. A WEAK OPEN WAVE TRIES TO SKIRT THE SRN EXTENT OF THE SFC
HIGH SAT AFTERNOON...BUT MODELS CONTINUE TO TREND IT FURTHER SOUTH
WELL OUT OF OUR REGION. AFTER LARGELY ZONAL FLOW ALOFT THROUGH
SUNDAY THE UPPER LEVEL PATTERN FAVORS SWRLY FLOW ON THE BACKSIDE
OF THE SFC HIGH. THIS WILL WORK TO DRIVE WARMER TEMPS INTO THE
FORECAST AREA WITH HIGHS DRIVING ABOVE AVERAGE HEADING INTO EARLY
NEXT WEEK.
TAX

&&

.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
WHILE IN GENERAL AGREEMENT ON DEEPENING UPPER LEVEL CLOSED LOW OVER
THE GREAT LAKES TUESDAY THROUGH THURSDAY WITH PERIODS OF RAIN INTO
WEDNESDAY UNTIL COLD FRONT WILL CHANGE PRECIP OVER TO SNOW SHOWERS
LATER WEDNESDAY AND THURSDAY. WINDS WILL BE ON THE INCREASE
THURSDAY AS SURFACE LOW WRAPS UP NORTH OF THE REGION. QPF ON THE
FRONT SIDE OF SYSTEM WILL BE NEAR AN INCH...WHICH SHOULD NOT
PRODUCE ANY SIGNIFICANT PROBLEMS. BACKLASH SNOW WEDNESDAY NIGHT
INTO THURSDAY WILL BE LIGHT WITH ONLY MINOR ACCUMULATIONS
EXPECTED. FLOW BEHIND COLD FRONT LOOKS TO STAY SOUTHWESTERLY WHICH
LOOKS TO LIMIT LAKE ENHANCED AMOUNTS ALONG I-80 AND THE RIDGES.
COLDER TEMPERATURES WILL THEN MODERATE FRIDAY AS MID LEVEL FLOW
QUICKLY BECOMES ZONAL.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
ISOLATED IFR SNOW SHOWERS AND FOG WILL END BY 20Z WITH GENERAL
MVFR EXPECTED THROUGH TONIGHT.


OUTLOOK.../SATURDAY FRIDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY AND WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$













000
FXUS61 KPBZ 191804
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
104 PM EST FRI DEC 19 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
SCATTERED FLURRIES MAY LAST FOR JUST A FEW MORE HOURS AS WEAKENING
NORTHWEST FLOW MAY PROVIDE FOR SOME LAKE ENHANCED FLURRIES IN THE
LINGERING LOW LEVEL MOISTURE. THE UPPER TROUGH WILL DEPART EAST
AND BE REPLACED BY RIDGING TONIGHT. MODEL PROFILES SUGGEST THAT
SOME MOISTURE WILL REMAIN TRAPPED UNDER THE BUILDING UPPER
RIDGE...PREVENTING US FROM CLEARING OUT THIS EVENING. THIS ISN`T
COMPLETELY CLEAR CUT...BUT WILL OPT TO KEEP MOSTLY CLOUDY WORDING
UNLESS SATELLITE OBSERVATIONS SHOW OTHERWISE. DID DROP TEMPS FOR THE REST OF
THE AFTERNOON AS CLOUD COVER SHOULD KEEP TEMPERATURES FROM WARMING
MUCH ABOVE CURRENT VALUES. LOWS TONIGHT WERE KEPT NEAR MET
GUIDANCE.

&&

.SHORT TERM /SATURDAY THROUGH MONDAY/...
HIGH PRESSURE WILL REIGN OVER THE FORECAST AREA THROUGH THE
WEEKEND. A WEAK OPEN WAVE TRIES TO SKIRT THE SRN EXTENT OF THE SFC
HIGH SAT AFTERNOON...BUT MODELS CONTINUE TO TREND IT FURTHER SOUTH
WELL OUT OF OUR REGION. AFTER LARGELY ZONAL FLOW ALOFT THROUGH
SUNDAY THE UPPER LEVEL PATTERN FAVORS SWRLY FLOW ON THE BACKSIDE
OF THE SFC HIGH. THIS WILL WORK TO DRIVE WARMER TEMPS INTO THE
FORECAST AREA WITH HIGHS DRIVING ABOVE AVERAGE HEADING INTO EARLY
NEXT WEEK.
TAX

&&

.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
WHILE IN GENERAL AGREEMENT ON DEEPENING UPPER LEVEL CLOSED LOW OVER
THE GREAT LAKES TUESDAY THROUGH THURSDAY WITH PERIODS OF RAIN INTO
WEDNESDAY UNTIL COLD FRONT WILL CHANGE PRECIP OVER TO SNOW SHOWERS
LATER WEDNESDAY AND THURSDAY. WINDS WILL BE ON THE INCREASE
THURSDAY AS SURFACE LOW WRAPS UP NORTH OF THE REGION. QPF ON THE
FRONT SIDE OF SYSTEM WILL BE NEAR AN INCH...WHICH SHOULD NOT
PRODUCE ANY SIGNIFICANT PROBLEMS. BACKLASH SNOW WEDNESDAY NIGHT
INTO THURSDAY WILL BE LIGHT WITH ONLY MINOR ACCUMULATIONS
EXPECTED. FLOW BEHIND COLD FRONT LOOKS TO STAY SOUTHWESTERLY WHICH
LOOKS TO LIMIT LAKE ENHANCED AMOUNTS ALONG I-80 AND THE RIDGES.
COLDER TEMPERATURES WILL THEN MODERATE FRIDAY AS MID LEVEL FLOW
QUICKLY BECOMES ZONAL.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
ISOLATED IFR SNOW SHOWERS AND FOG WILL END BY 20Z WITH GENERAL
MVFR EXPECTED THROUGH TONIGHT.


OUTLOOK.../SATURDAY FRIDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY AND WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$













000
FXUS61 KPBZ 191804
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
104 PM EST FRI DEC 19 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
SCATTERED FLURRIES MAY LAST FOR JUST A FEW MORE HOURS AS WEAKENING
NORTHWEST FLOW MAY PROVIDE FOR SOME LAKE ENHANCED FLURRIES IN THE
LINGERING LOW LEVEL MOISTURE. THE UPPER TROUGH WILL DEPART EAST
AND BE REPLACED BY RIDGING TONIGHT. MODEL PROFILES SUGGEST THAT
SOME MOISTURE WILL REMAIN TRAPPED UNDER THE BUILDING UPPER
RIDGE...PREVENTING US FROM CLEARING OUT THIS EVENING. THIS ISN`T
COMPLETELY CLEAR CUT...BUT WILL OPT TO KEEP MOSTLY CLOUDY WORDING
UNLESS SATELLITE OBSERVATIONS SHOW OTHERWISE. DID DROP TEMPS FOR THE REST OF
THE AFTERNOON AS CLOUD COVER SHOULD KEEP TEMPERATURES FROM WARMING
MUCH ABOVE CURRENT VALUES. LOWS TONIGHT WERE KEPT NEAR MET
GUIDANCE.

&&

.SHORT TERM /SATURDAY THROUGH MONDAY/...
HIGH PRESSURE WILL REIGN OVER THE FORECAST AREA THROUGH THE
WEEKEND. A WEAK OPEN WAVE TRIES TO SKIRT THE SRN EXTENT OF THE SFC
HIGH SAT AFTERNOON...BUT MODELS CONTINUE TO TREND IT FURTHER SOUTH
WELL OUT OF OUR REGION. AFTER LARGELY ZONAL FLOW ALOFT THROUGH
SUNDAY THE UPPER LEVEL PATTERN FAVORS SWRLY FLOW ON THE BACKSIDE
OF THE SFC HIGH. THIS WILL WORK TO DRIVE WARMER TEMPS INTO THE
FORECAST AREA WITH HIGHS DRIVING ABOVE AVERAGE HEADING INTO EARLY
NEXT WEEK.
TAX

&&

.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
WHILE IN GENERAL AGREEMENT ON DEEPENING UPPER LEVEL CLOSED LOW OVER
THE GREAT LAKES TUESDAY THROUGH THURSDAY WITH PERIODS OF RAIN INTO
WEDNESDAY UNTIL COLD FRONT WILL CHANGE PRECIP OVER TO SNOW SHOWERS
LATER WEDNESDAY AND THURSDAY. WINDS WILL BE ON THE INCREASE
THURSDAY AS SURFACE LOW WRAPS UP NORTH OF THE REGION. QPF ON THE
FRONT SIDE OF SYSTEM WILL BE NEAR AN INCH...WHICH SHOULD NOT
PRODUCE ANY SIGNIFICANT PROBLEMS. BACKLASH SNOW WEDNESDAY NIGHT
INTO THURSDAY WILL BE LIGHT WITH ONLY MINOR ACCUMULATIONS
EXPECTED. FLOW BEHIND COLD FRONT LOOKS TO STAY SOUTHWESTERLY WHICH
LOOKS TO LIMIT LAKE ENHANCED AMOUNTS ALONG I-80 AND THE RIDGES.
COLDER TEMPERATURES WILL THEN MODERATE FRIDAY AS MID LEVEL FLOW
QUICKLY BECOMES ZONAL.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
ISOLATED IFR SNOW SHOWERS AND FOG WILL END BY 20Z WITH GENERAL
MVFR EXPECTED THROUGH TONIGHT.


OUTLOOK.../SATURDAY FRIDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY AND WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$













000
FXUS61 KPBZ 191720
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
1220 PM EST FRI DEC 19 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND...THOUGH
CLOUDS WILL REMAIN.

&&

.NEAR TERM /THROUGH TONIGHT/...
FINE LINE ON RADAR IS THE BACK EDGE OF FREEZING DRIZZLE AND
FLURRIES WITH SURFACE TROUGH AND BACK EDGE OF STRETCHED VORT
BEHIND SHORTWAVE EXITING EAST. ALLOWED ADVISORIES TO EXPIRE AS
RADAR TRENDS AND SURFACE OBS SHOW DIMINISHING TREND TO PRECIP AND
HAVE ISSUED SPS TO COVER REMAINING PATCHY PRECIP. FORECAST
SOUNDINGS SHOW CLOUDS MAY HOLD IN THROUGH TONIGHT SO HAVE ADJUSTED
SKY GRIDS UP. NO CHANGE TO PREVIOUS TEMPERATURE.

&&

.SHORT TERM /SATURDAY THROUGH MONDAY/...
HIGH PRESSURE WILL REIGN OVER THE FORECAST AREA THROUGH THE
WEEKEND. A WEAK OPEN WAVE TRIES TO SKIRT THE SRN EXTENT OF THE SFC
HIGH SAT AFTERNOON...BUT MODELS CONTINUE TO TREND IT FURTHER SOUTH
WELL OUT OF OUR REGION. AFTER LARGELY ZONAL FLOW ALOFT THROUGH
SUNDAY THE UPPER LEVEL PATTERN FAVORS SWRLY FLOW ON THE BACKSIDE
OF THE SFC HIGH. THIS WILL WORK TO DRIVE WARMER TEMPS INTO THE
FORECAST AREA WITH HIGHS DRIVING ABOVE AVERAGE HEADING INTO EARLY
NEXT WEEK.
TAX

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
WHILE IN GENERAL AGREEMENT ON DEEPENING UPPER LEVEL CLOSED LOW OVER
THE GREAT LAKES TUESDAY THROUGH THURSDAY WITH PERIODS OF RAIN INTO
WEDNESDAY UNTIL COLD FRONT WILL CHANGE PRECIP OVER TO SNOW SHOWERS
LATER WEDNESDAY AND THURSDAY. WINDS WILL BE ON THE INCREASE
THURSDAY AS SURFACE LOW WRAPS UP NORTH OF THE REGION. QPF ON THE
FRONT SIDE OF SYSTEM WILL BE NEAR AN INCH...WHICH SHOULD NOT
PRODUCE ANY SIGNIFICANT PROBLEMS. BACKLASH SNOW WEDNESDAY NIGHT
INTO THURSDAY WILL BE LIGHT WITH ONLY MINOR ACCUMULATIONS
EXPECTED. FLOW BEHIND COLD FRONT LOOKS TO STAY SOUTHWESTERLY WHICH
LOOKS TO LIMIT LAKE ENHANCED AMOUNTS ALONG I-80 AND THE RIDGES.
COLDER TEMPERATURES WILL THEN MODERATE FRIDAY AS MID LEVEL FLOW
QUICKLY BECOMES ZONAL.

&&

.AVIATION /17Z FRIDAY THROUGH WEDNESDAY/...
ISOLATED IFR SNOW SHOWERS AND FOG WILL END BY 20Z WITH GENERAL
MVFR EXPECTED THROUGH TONIGHT.


OUTLOOK.../SATURDAY FRIDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY AND WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$








000
FXUS61 KPBZ 191720
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
1220 PM EST FRI DEC 19 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND...THOUGH
CLOUDS WILL REMAIN.

&&

.NEAR TERM /THROUGH TONIGHT/...
FINE LINE ON RADAR IS THE BACK EDGE OF FREEZING DRIZZLE AND
FLURRIES WITH SURFACE TROUGH AND BACK EDGE OF STRETCHED VORT
BEHIND SHORTWAVE EXITING EAST. ALLOWED ADVISORIES TO EXPIRE AS
RADAR TRENDS AND SURFACE OBS SHOW DIMINISHING TREND TO PRECIP AND
HAVE ISSUED SPS TO COVER REMAINING PATCHY PRECIP. FORECAST
SOUNDINGS SHOW CLOUDS MAY HOLD IN THROUGH TONIGHT SO HAVE ADJUSTED
SKY GRIDS UP. NO CHANGE TO PREVIOUS TEMPERATURE.

&&

.SHORT TERM /SATURDAY THROUGH MONDAY/...
HIGH PRESSURE WILL REIGN OVER THE FORECAST AREA THROUGH THE
WEEKEND. A WEAK OPEN WAVE TRIES TO SKIRT THE SRN EXTENT OF THE SFC
HIGH SAT AFTERNOON...BUT MODELS CONTINUE TO TREND IT FURTHER SOUTH
WELL OUT OF OUR REGION. AFTER LARGELY ZONAL FLOW ALOFT THROUGH
SUNDAY THE UPPER LEVEL PATTERN FAVORS SWRLY FLOW ON THE BACKSIDE
OF THE SFC HIGH. THIS WILL WORK TO DRIVE WARMER TEMPS INTO THE
FORECAST AREA WITH HIGHS DRIVING ABOVE AVERAGE HEADING INTO EARLY
NEXT WEEK.
TAX

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
WHILE IN GENERAL AGREEMENT ON DEEPENING UPPER LEVEL CLOSED LOW OVER
THE GREAT LAKES TUESDAY THROUGH THURSDAY WITH PERIODS OF RAIN INTO
WEDNESDAY UNTIL COLD FRONT WILL CHANGE PRECIP OVER TO SNOW SHOWERS
LATER WEDNESDAY AND THURSDAY. WINDS WILL BE ON THE INCREASE
THURSDAY AS SURFACE LOW WRAPS UP NORTH OF THE REGION. QPF ON THE
FRONT SIDE OF SYSTEM WILL BE NEAR AN INCH...WHICH SHOULD NOT
PRODUCE ANY SIGNIFICANT PROBLEMS. BACKLASH SNOW WEDNESDAY NIGHT
INTO THURSDAY WILL BE LIGHT WITH ONLY MINOR ACCUMULATIONS
EXPECTED. FLOW BEHIND COLD FRONT LOOKS TO STAY SOUTHWESTERLY WHICH
LOOKS TO LIMIT LAKE ENHANCED AMOUNTS ALONG I-80 AND THE RIDGES.
COLDER TEMPERATURES WILL THEN MODERATE FRIDAY AS MID LEVEL FLOW
QUICKLY BECOMES ZONAL.

&&

.AVIATION /17Z FRIDAY THROUGH WEDNESDAY/...
ISOLATED IFR SNOW SHOWERS AND FOG WILL END BY 20Z WITH GENERAL
MVFR EXPECTED THROUGH TONIGHT.


OUTLOOK.../SATURDAY FRIDAY NIGHT THROUGH WEDNESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY AND WEDNESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$









000
FXUS61 KCTP 191547
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1047 AM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE OVER THE GREAT LAKES WILL SLIDE EAST INTO
PENNSYLVANIA THIS WEEKEND. A DEEP UPPER TROUGH AND ASSOCIATED SFC
LOW WILL LIFT NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE
OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SHALLOW COLD...MOIST AIR TRAPPED BELOW A MODERATELY STRONG
SUBSIDENCE INVERSION /BASED AT AROUND 2-3KFT AGL/ WILL CONTINUE TO
PRODUCE WIDESPREAD STRATUS AND STRATOCU THROUGH THE REST OF TODAY.
THERE/S A CHC FOR SOME BREAKS OF SUNSHINE ACROSS THE SE DURING THE
MID TO LATE AFTERNOON HOURS AS SHALLOW VERTICAL MIXING UNDER THE
LOW LATE DEC SUN ANGLE TRIES TO POKE OF A FEW HOLES IN THE
STRATOCU DECK.

OROGRAPHIC FORCING OF THE SHALLOW LYR OF MOISTURE VIA A WELL-
ALIGNED NWRLY FLOW SHOULD CONTINUE TO PRODUCE A BIT OF VERY LGT
SNOW OR -FZDZ ACROSS CAMBRIA/SOMERSET COUNTIES THRU AT LEAST 18Z.

HOWEVER...GIVEN THE VERY LGT NATURE OF THE PRECIP AND THAT SOME
IS FALLING AS SNOW...HAVE OPTED TO CONTINUE COVERING THE MINOR EVENT
WITH AN SPS RATHER THAN A WSW. SFC OBS HAVE BEEN INDICATING BOTH
-SHSN AND -FZDZ AND MDL SOUNDINGS INDICATE BORDERLINE CLOUD TOP
TEMPS OF ARND -10C...SO WILL CONTINUE TO FCST SCT -SHSN AND PATCHY
-FZDZ OVR THE LAUREL HIGHLANDS THIS AM.

MAX TEMPS SHOULD BE SIMILAR TO THURSDAY...WITH U20S OVR THE
HIGHEST TERRAIN OF THE ALLEGHENIES...TO THE U30S ACROSS THE LOWER
SUSQ VALLEY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
HIGH PRESSURE AND ASSOC DRIER AIR MASS WILL BUILD IN FROM THE GRT
LKS TONIGHT...PROVIDING THE AREA WITH FAIR WX. FOR MUCH OF CENTRAL
PA...TONIGHT SHOULD FEATURE MCLEAR SKIES. HOWEVER...LOW LVL
MOISTURE TRAPPED BENEATH INVERSION MAY RESULT IN PERSISTENT
STRATOCU ACROSS THE LAUREL HIGHLANDS THIS EVENING.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS INTO THE REGION ON SATURDAY.
HOWEVER...ALL MDL DATA SUPPORTS A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS IN THE 30S.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE WILL SHIFT SLOWLY EASTWARD FROM THE GREAT LAKES
INTO NORTHERN NEW ENGLAND BY 12Z MONDAY. A MOISTURE-STARVED NRN
STREAM SHORTWAVE SHOULD PRODUCE A PERIOD OF CLOUDINESS SAT
NIGHT...BUT LIKELY NOT PRODUCE ANY PRECIP. LATEST MDL SOUNDINGS
POINT TOWARD A RELATIVELY BRIGHT SUNDAY IN THE WAKE OF THIS
FEATURE WITH NEAR SEASONAL TEMPS. SPLIT FLOW REGIME ACROSS THE
LOWER 48 WILL TRANSITION TO A HIGHLY AMPLIFIED PATTERN BY EARLY
NEXT WEEK ACROSS THE LOWER 48...WITH A DEEP NEGATIVELY TILTED
TROUGH EVOLVING OVER THE EASTERN 1/3RD OF THE CONUS.

THE MODELS SEEM TO BE FORMING A CONSENSUS ON THE PESKY LOW
THAT REFUSES TO BE WELL FORECAST...LIFTING IT SLOWLY FROM FL
PANHANDLE NNEWD JUST OFF THE EAST COAST SUN-MON ALONG A LOW LEVEL
BAROCLINIC ZONE THAT MAY NOT BUDGE PAST THE GULF STREAM AS THE
FLOW ALOFT TURNS SOUTHWESTERLY/PARALLEL TO THE COASTAL FRONT.
INCREASED POPS FOR MONDAY OVER THE SE BASED ON MULTI-MODEL/WPC
BLEND. COMPLEX SFC PATTERN WITH SOME HINTS AT LOW LEVEL CAD ALONG
WITH WAA ALOFT VIA SLY FLOW COULD MAKE FOR A MESSY MIXED PTYPE
TRANSITION.

AN INTENSE TRIPLE POINT SYSTEM DEVELOPING ON DEC 23-24 WILL
LIKELY STEAL THE HEADLINES GIVEN ITS TIMING AND LARGE PORTION OF
REAL ESTATE THAT WILL BE AFFECTED. WHILE THE DETAILS REMAIN
UNCLEAR AT THIS POINT...TEMPERATURES SHOULD BE WARM ENOUGH TO
SUPPORT RAIN ON THE FRONT SIDE OF THE SYSTEM BEFORE BRISK WNW
WINDS DRIVE STRONG CAA EAST OF THE APPALACHIANS. THE TIMING OF THE
COLD/OCCLUDED FRONT WILL BE KEY FOR PRECIPITATION TRANSITION FROM
RAIN TO SNOW SHOWERS. AS THE SYSTEM SPINS UP INTO EASTERN
CANADA...THE STRONG CAA CIRCULATING THROUGH THE GREAT LAKES AND OH
VLY SHOULD LEAD TO LAKE EFFECT/UPSLOPE/WRAP AROUND SNOW SHOWERS
OVER THE WESTERN ALLEGHENIES BY CHRISTMAS DAY. A PERIOD OF STRONG
GUSTY WINDS ARE HIGHLY PROBABLE AS THE DYNAMIC SYSTEM INTENSIFIES
SHIFTING NWWD FROM NEW ENGLAND INTO ONTARIO/QUEBEC.

THE TAKE HOME MESSAGE IS THAT A VOLATILE PERIOD OF WEATHER WILL
IMPACT THE AREA THROUGH CHRISTMAS DAY WITH POTENTIAL WIND...RAIN
AND SNOW IMPACTS ALL ON THE TABLE. STAY TUNED.

&&

.AVIATION /16Z FRIDAY THROUGH TUESDAY/...
SFC TROUGH DROPPING SOUTHWARD THIS MORNING WILL GRADUALLY WASH
OUT. RIBBON OF HIGHER LOW LVL MOISTURE ALONG AND IN ADVANCE OF
THIS FEATURE WILL CONTINUE TO SUPPORT SPOTTY LGT SNOW/FZDZ ACROSS
THE ALLEGHENY MTNS THROUGH AROUND 18Z...BRINGING ICING CONCERNS
FOR AVIATION INTERESTS. IFR CONDITIONS ONGOING MAINLY AT KJST
WITH WIDESPREAD MVFR ELSEWHERE ACROSS THE CENTRAL AND NW MTNS. LOW
END MVFR STRATO CU CLOUD DECK WILL PERSIST ACROSS THE SUSQ VALLEY
THROUGH MUCH OF THE DAY.

OROGRAPHIC FORCING OF SHALLOW LYR OF MOISTURE SHOULD CONTINUE TO
PRODUCE A BIT OF LGT SNOW OR FZDZ AROUND KJST THROUGH LATE MORNING.
OTHERWISE...ARRIVAL OF DRIER AIR IN WAKE OF TROF SHOULD PRODUCE
GRADUALLY LIFTING CIGS WITH PARTIAL CLEARING LATER TODAY...ESP
WHERE WEST WIND DOWNSLOPES THE MTNS ACROSS THE SUSQ VALLEY AND SE
HALF OF CWA. NORTHWEST WINDS WILL BE AROUND 10 KTS WITH HIGHER
GUSTS.

HIGH PRESSURE BUILDS IN TONIGHT...WITH MAINLY VFR CONDITIONS. SOME
MVFR CIGS MAY DEVELOP AGAIN OVER THE NW MTNS AT KBFD. AND LIGHT
WINDS MAY PRODUCE SOME LOCAL FOG RESTRICTIONS IN SPOTS.

OUTLOOK...

SAT-SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD/LAMBERT
NEAR TERM...FITZGERALD/LAMBERT
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/STEINBUGL
AVIATION...LAMBERT/RXR




000
FXUS61 KCTP 191547
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1047 AM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE OVER THE GREAT LAKES WILL SLIDE EAST INTO
PENNSYLVANIA THIS WEEKEND. A DEEP UPPER TROUGH AND ASSOCIATED SFC
LOW WILL LIFT NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE
OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SHALLOW COLD...MOIST AIR TRAPPED BELOW A MODERATELY STRONG
SUBSIDENCE INVERSION /BASED AT AROUND 2-3KFT AGL/ WILL CONTINUE TO
PRODUCE WIDESPREAD STRATUS AND STRATOCU THROUGH THE REST OF TODAY.
THERE/S A CHC FOR SOME BREAKS OF SUNSHINE ACROSS THE SE DURING THE
MID TO LATE AFTERNOON HOURS AS SHALLOW VERTICAL MIXING UNDER THE
LOW LATE DEC SUN ANGLE TRIES TO POKE OF A FEW HOLES IN THE
STRATOCU DECK.

OROGRAPHIC FORCING OF THE SHALLOW LYR OF MOISTURE VIA A WELL-
ALIGNED NWRLY FLOW SHOULD CONTINUE TO PRODUCE A BIT OF VERY LGT
SNOW OR -FZDZ ACROSS CAMBRIA/SOMERSET COUNTIES THRU AT LEAST 18Z.

HOWEVER...GIVEN THE VERY LGT NATURE OF THE PRECIP AND THAT SOME
IS FALLING AS SNOW...HAVE OPTED TO CONTINUE COVERING THE MINOR EVENT
WITH AN SPS RATHER THAN A WSW. SFC OBS HAVE BEEN INDICATING BOTH
-SHSN AND -FZDZ AND MDL SOUNDINGS INDICATE BORDERLINE CLOUD TOP
TEMPS OF ARND -10C...SO WILL CONTINUE TO FCST SCT -SHSN AND PATCHY
-FZDZ OVR THE LAUREL HIGHLANDS THIS AM.

MAX TEMPS SHOULD BE SIMILAR TO THURSDAY...WITH U20S OVR THE
HIGHEST TERRAIN OF THE ALLEGHENIES...TO THE U30S ACROSS THE LOWER
SUSQ VALLEY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
HIGH PRESSURE AND ASSOC DRIER AIR MASS WILL BUILD IN FROM THE GRT
LKS TONIGHT...PROVIDING THE AREA WITH FAIR WX. FOR MUCH OF CENTRAL
PA...TONIGHT SHOULD FEATURE MCLEAR SKIES. HOWEVER...LOW LVL
MOISTURE TRAPPED BENEATH INVERSION MAY RESULT IN PERSISTENT
STRATOCU ACROSS THE LAUREL HIGHLANDS THIS EVENING.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS INTO THE REGION ON SATURDAY.
HOWEVER...ALL MDL DATA SUPPORTS A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS IN THE 30S.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE WILL SHIFT SLOWLY EASTWARD FROM THE GREAT LAKES
INTO NORTHERN NEW ENGLAND BY 12Z MONDAY. A MOISTURE-STARVED NRN
STREAM SHORTWAVE SHOULD PRODUCE A PERIOD OF CLOUDINESS SAT
NIGHT...BUT LIKELY NOT PRODUCE ANY PRECIP. LATEST MDL SOUNDINGS
POINT TOWARD A RELATIVELY BRIGHT SUNDAY IN THE WAKE OF THIS
FEATURE WITH NEAR SEASONAL TEMPS. SPLIT FLOW REGIME ACROSS THE
LOWER 48 WILL TRANSITION TO A HIGHLY AMPLIFIED PATTERN BY EARLY
NEXT WEEK ACROSS THE LOWER 48...WITH A DEEP NEGATIVELY TILTED
TROUGH EVOLVING OVER THE EASTERN 1/3RD OF THE CONUS.

THE MODELS SEEM TO BE FORMING A CONSENSUS ON THE PESKY LOW
THAT REFUSES TO BE WELL FORECAST...LIFTING IT SLOWLY FROM FL
PANHANDLE NNEWD JUST OFF THE EAST COAST SUN-MON ALONG A LOW LEVEL
BAROCLINIC ZONE THAT MAY NOT BUDGE PAST THE GULF STREAM AS THE
FLOW ALOFT TURNS SOUTHWESTERLY/PARALLEL TO THE COASTAL FRONT.
INCREASED POPS FOR MONDAY OVER THE SE BASED ON MULTI-MODEL/WPC
BLEND. COMPLEX SFC PATTERN WITH SOME HINTS AT LOW LEVEL CAD ALONG
WITH WAA ALOFT VIA SLY FLOW COULD MAKE FOR A MESSY MIXED PTYPE
TRANSITION.

AN INTENSE TRIPLE POINT SYSTEM DEVELOPING ON DEC 23-24 WILL
LIKELY STEAL THE HEADLINES GIVEN ITS TIMING AND LARGE PORTION OF
REAL ESTATE THAT WILL BE AFFECTED. WHILE THE DETAILS REMAIN
UNCLEAR AT THIS POINT...TEMPERATURES SHOULD BE WARM ENOUGH TO
SUPPORT RAIN ON THE FRONT SIDE OF THE SYSTEM BEFORE BRISK WNW
WINDS DRIVE STRONG CAA EAST OF THE APPALACHIANS. THE TIMING OF THE
COLD/OCCLUDED FRONT WILL BE KEY FOR PRECIPITATION TRANSITION FROM
RAIN TO SNOW SHOWERS. AS THE SYSTEM SPINS UP INTO EASTERN
CANADA...THE STRONG CAA CIRCULATING THROUGH THE GREAT LAKES AND OH
VLY SHOULD LEAD TO LAKE EFFECT/UPSLOPE/WRAP AROUND SNOW SHOWERS
OVER THE WESTERN ALLEGHENIES BY CHRISTMAS DAY. A PERIOD OF STRONG
GUSTY WINDS ARE HIGHLY PROBABLE AS THE DYNAMIC SYSTEM INTENSIFIES
SHIFTING NWWD FROM NEW ENGLAND INTO ONTARIO/QUEBEC.

THE TAKE HOME MESSAGE IS THAT A VOLATILE PERIOD OF WEATHER WILL
IMPACT THE AREA THROUGH CHRISTMAS DAY WITH POTENTIAL WIND...RAIN
AND SNOW IMPACTS ALL ON THE TABLE. STAY TUNED.

&&

.AVIATION /16Z FRIDAY THROUGH TUESDAY/...
SFC TROUGH DROPPING SOUTHWARD THIS MORNING WILL GRADUALLY WASH
OUT. RIBBON OF HIGHER LOW LVL MOISTURE ALONG AND IN ADVANCE OF
THIS FEATURE WILL CONTINUE TO SUPPORT SPOTTY LGT SNOW/FZDZ ACROSS
THE ALLEGHENY MTNS THROUGH AROUND 18Z...BRINGING ICING CONCERNS
FOR AVIATION INTERESTS. IFR CONDITIONS ONGOING MAINLY AT KJST
WITH WIDESPREAD MVFR ELSEWHERE ACROSS THE CENTRAL AND NW MTNS. LOW
END MVFR STRATO CU CLOUD DECK WILL PERSIST ACROSS THE SUSQ VALLEY
THROUGH MUCH OF THE DAY.

OROGRAPHIC FORCING OF SHALLOW LYR OF MOISTURE SHOULD CONTINUE TO
PRODUCE A BIT OF LGT SNOW OR FZDZ AROUND KJST THROUGH LATE MORNING.
OTHERWISE...ARRIVAL OF DRIER AIR IN WAKE OF TROF SHOULD PRODUCE
GRADUALLY LIFTING CIGS WITH PARTIAL CLEARING LATER TODAY...ESP
WHERE WEST WIND DOWNSLOPES THE MTNS ACROSS THE SUSQ VALLEY AND SE
HALF OF CWA. NORTHWEST WINDS WILL BE AROUND 10 KTS WITH HIGHER
GUSTS.

HIGH PRESSURE BUILDS IN TONIGHT...WITH MAINLY VFR CONDITIONS. SOME
MVFR CIGS MAY DEVELOP AGAIN OVER THE NW MTNS AT KBFD. AND LIGHT
WINDS MAY PRODUCE SOME LOCAL FOG RESTRICTIONS IN SPOTS.

OUTLOOK...

SAT-SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD/LAMBERT
NEAR TERM...FITZGERALD/LAMBERT
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/STEINBUGL
AVIATION...LAMBERT/RXR




000
FXUS61 KCTP 191547
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1047 AM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE OVER THE GREAT LAKES WILL SLIDE EAST INTO
PENNSYLVANIA THIS WEEKEND. A DEEP UPPER TROUGH AND ASSOCIATED SFC
LOW WILL LIFT NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE
OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SHALLOW COLD...MOIST AIR TRAPPED BELOW A MODERATELY STRONG
SUBSIDENCE INVERSION /BASED AT AROUND 2-3KFT AGL/ WILL CONTINUE TO
PRODUCE WIDESPREAD STRATUS AND STRATOCU THROUGH THE REST OF TODAY.
THERE/S A CHC FOR SOME BREAKS OF SUNSHINE ACROSS THE SE DURING THE
MID TO LATE AFTERNOON HOURS AS SHALLOW VERTICAL MIXING UNDER THE
LOW LATE DEC SUN ANGLE TRIES TO POKE OF A FEW HOLES IN THE
STRATOCU DECK.

OROGRAPHIC FORCING OF THE SHALLOW LYR OF MOISTURE VIA A WELL-
ALIGNED NWRLY FLOW SHOULD CONTINUE TO PRODUCE A BIT OF VERY LGT
SNOW OR -FZDZ ACROSS CAMBRIA/SOMERSET COUNTIES THRU AT LEAST 18Z.

HOWEVER...GIVEN THE VERY LGT NATURE OF THE PRECIP AND THAT SOME
IS FALLING AS SNOW...HAVE OPTED TO CONTINUE COVERING THE MINOR EVENT
WITH AN SPS RATHER THAN A WSW. SFC OBS HAVE BEEN INDICATING BOTH
-SHSN AND -FZDZ AND MDL SOUNDINGS INDICATE BORDERLINE CLOUD TOP
TEMPS OF ARND -10C...SO WILL CONTINUE TO FCST SCT -SHSN AND PATCHY
-FZDZ OVR THE LAUREL HIGHLANDS THIS AM.

MAX TEMPS SHOULD BE SIMILAR TO THURSDAY...WITH U20S OVR THE
HIGHEST TERRAIN OF THE ALLEGHENIES...TO THE U30S ACROSS THE LOWER
SUSQ VALLEY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
HIGH PRESSURE AND ASSOC DRIER AIR MASS WILL BUILD IN FROM THE GRT
LKS TONIGHT...PROVIDING THE AREA WITH FAIR WX. FOR MUCH OF CENTRAL
PA...TONIGHT SHOULD FEATURE MCLEAR SKIES. HOWEVER...LOW LVL
MOISTURE TRAPPED BENEATH INVERSION MAY RESULT IN PERSISTENT
STRATOCU ACROSS THE LAUREL HIGHLANDS THIS EVENING.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS INTO THE REGION ON SATURDAY.
HOWEVER...ALL MDL DATA SUPPORTS A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS IN THE 30S.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE WILL SHIFT SLOWLY EASTWARD FROM THE GREAT LAKES
INTO NORTHERN NEW ENGLAND BY 12Z MONDAY. A MOISTURE-STARVED NRN
STREAM SHORTWAVE SHOULD PRODUCE A PERIOD OF CLOUDINESS SAT
NIGHT...BUT LIKELY NOT PRODUCE ANY PRECIP. LATEST MDL SOUNDINGS
POINT TOWARD A RELATIVELY BRIGHT SUNDAY IN THE WAKE OF THIS
FEATURE WITH NEAR SEASONAL TEMPS. SPLIT FLOW REGIME ACROSS THE
LOWER 48 WILL TRANSITION TO A HIGHLY AMPLIFIED PATTERN BY EARLY
NEXT WEEK ACROSS THE LOWER 48...WITH A DEEP NEGATIVELY TILTED
TROUGH EVOLVING OVER THE EASTERN 1/3RD OF THE CONUS.

THE MODELS SEEM TO BE FORMING A CONSENSUS ON THE PESKY LOW
THAT REFUSES TO BE WELL FORECAST...LIFTING IT SLOWLY FROM FL
PANHANDLE NNEWD JUST OFF THE EAST COAST SUN-MON ALONG A LOW LEVEL
BAROCLINIC ZONE THAT MAY NOT BUDGE PAST THE GULF STREAM AS THE
FLOW ALOFT TURNS SOUTHWESTERLY/PARALLEL TO THE COASTAL FRONT.
INCREASED POPS FOR MONDAY OVER THE SE BASED ON MULTI-MODEL/WPC
BLEND. COMPLEX SFC PATTERN WITH SOME HINTS AT LOW LEVEL CAD ALONG
WITH WAA ALOFT VIA SLY FLOW COULD MAKE FOR A MESSY MIXED PTYPE
TRANSITION.

AN INTENSE TRIPLE POINT SYSTEM DEVELOPING ON DEC 23-24 WILL
LIKELY STEAL THE HEADLINES GIVEN ITS TIMING AND LARGE PORTION OF
REAL ESTATE THAT WILL BE AFFECTED. WHILE THE DETAILS REMAIN
UNCLEAR AT THIS POINT...TEMPERATURES SHOULD BE WARM ENOUGH TO
SUPPORT RAIN ON THE FRONT SIDE OF THE SYSTEM BEFORE BRISK WNW
WINDS DRIVE STRONG CAA EAST OF THE APPALACHIANS. THE TIMING OF THE
COLD/OCCLUDED FRONT WILL BE KEY FOR PRECIPITATION TRANSITION FROM
RAIN TO SNOW SHOWERS. AS THE SYSTEM SPINS UP INTO EASTERN
CANADA...THE STRONG CAA CIRCULATING THROUGH THE GREAT LAKES AND OH
VLY SHOULD LEAD TO LAKE EFFECT/UPSLOPE/WRAP AROUND SNOW SHOWERS
OVER THE WESTERN ALLEGHENIES BY CHRISTMAS DAY. A PERIOD OF STRONG
GUSTY WINDS ARE HIGHLY PROBABLE AS THE DYNAMIC SYSTEM INTENSIFIES
SHIFTING NWWD FROM NEW ENGLAND INTO ONTARIO/QUEBEC.

THE TAKE HOME MESSAGE IS THAT A VOLATILE PERIOD OF WEATHER WILL
IMPACT THE AREA THROUGH CHRISTMAS DAY WITH POTENTIAL WIND...RAIN
AND SNOW IMPACTS ALL ON THE TABLE. STAY TUNED.

&&

.AVIATION /16Z FRIDAY THROUGH TUESDAY/...
SFC TROUGH DROPPING SOUTHWARD THIS MORNING WILL GRADUALLY WASH
OUT. RIBBON OF HIGHER LOW LVL MOISTURE ALONG AND IN ADVANCE OF
THIS FEATURE WILL CONTINUE TO SUPPORT SPOTTY LGT SNOW/FZDZ ACROSS
THE ALLEGHENY MTNS THROUGH AROUND 18Z...BRINGING ICING CONCERNS
FOR AVIATION INTERESTS. IFR CONDITIONS ONGOING MAINLY AT KJST
WITH WIDESPREAD MVFR ELSEWHERE ACROSS THE CENTRAL AND NW MTNS. LOW
END MVFR STRATO CU CLOUD DECK WILL PERSIST ACROSS THE SUSQ VALLEY
THROUGH MUCH OF THE DAY.

OROGRAPHIC FORCING OF SHALLOW LYR OF MOISTURE SHOULD CONTINUE TO
PRODUCE A BIT OF LGT SNOW OR FZDZ AROUND KJST THROUGH LATE MORNING.
OTHERWISE...ARRIVAL OF DRIER AIR IN WAKE OF TROF SHOULD PRODUCE
GRADUALLY LIFTING CIGS WITH PARTIAL CLEARING LATER TODAY...ESP
WHERE WEST WIND DOWNSLOPES THE MTNS ACROSS THE SUSQ VALLEY AND SE
HALF OF CWA. NORTHWEST WINDS WILL BE AROUND 10 KTS WITH HIGHER
GUSTS.

HIGH PRESSURE BUILDS IN TONIGHT...WITH MAINLY VFR CONDITIONS. SOME
MVFR CIGS MAY DEVELOP AGAIN OVER THE NW MTNS AT KBFD. AND LIGHT
WINDS MAY PRODUCE SOME LOCAL FOG RESTRICTIONS IN SPOTS.

OUTLOOK...

SAT-SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD/LAMBERT
NEAR TERM...FITZGERALD/LAMBERT
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/STEINBUGL
AVIATION...LAMBERT/RXR




000
FXUS61 KCTP 191547
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1047 AM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE OVER THE GREAT LAKES WILL SLIDE EAST INTO
PENNSYLVANIA THIS WEEKEND. A DEEP UPPER TROUGH AND ASSOCIATED SFC
LOW WILL LIFT NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE
OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SHALLOW COLD...MOIST AIR TRAPPED BELOW A MODERATELY STRONG
SUBSIDENCE INVERSION /BASED AT AROUND 2-3KFT AGL/ WILL CONTINUE TO
PRODUCE WIDESPREAD STRATUS AND STRATOCU THROUGH THE REST OF TODAY.
THERE/S A CHC FOR SOME BREAKS OF SUNSHINE ACROSS THE SE DURING THE
MID TO LATE AFTERNOON HOURS AS SHALLOW VERTICAL MIXING UNDER THE
LOW LATE DEC SUN ANGLE TRIES TO POKE OF A FEW HOLES IN THE
STRATOCU DECK.

OROGRAPHIC FORCING OF THE SHALLOW LYR OF MOISTURE VIA A WELL-
ALIGNED NWRLY FLOW SHOULD CONTINUE TO PRODUCE A BIT OF VERY LGT
SNOW OR -FZDZ ACROSS CAMBRIA/SOMERSET COUNTIES THRU AT LEAST 18Z.

HOWEVER...GIVEN THE VERY LGT NATURE OF THE PRECIP AND THAT SOME
IS FALLING AS SNOW...HAVE OPTED TO CONTINUE COVERING THE MINOR EVENT
WITH AN SPS RATHER THAN A WSW. SFC OBS HAVE BEEN INDICATING BOTH
-SHSN AND -FZDZ AND MDL SOUNDINGS INDICATE BORDERLINE CLOUD TOP
TEMPS OF ARND -10C...SO WILL CONTINUE TO FCST SCT -SHSN AND PATCHY
-FZDZ OVR THE LAUREL HIGHLANDS THIS AM.

MAX TEMPS SHOULD BE SIMILAR TO THURSDAY...WITH U20S OVR THE
HIGHEST TERRAIN OF THE ALLEGHENIES...TO THE U30S ACROSS THE LOWER
SUSQ VALLEY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
HIGH PRESSURE AND ASSOC DRIER AIR MASS WILL BUILD IN FROM THE GRT
LKS TONIGHT...PROVIDING THE AREA WITH FAIR WX. FOR MUCH OF CENTRAL
PA...TONIGHT SHOULD FEATURE MCLEAR SKIES. HOWEVER...LOW LVL
MOISTURE TRAPPED BENEATH INVERSION MAY RESULT IN PERSISTENT
STRATOCU ACROSS THE LAUREL HIGHLANDS THIS EVENING.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS INTO THE REGION ON SATURDAY.
HOWEVER...ALL MDL DATA SUPPORTS A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS IN THE 30S.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE WILL SHIFT SLOWLY EASTWARD FROM THE GREAT LAKES
INTO NORTHERN NEW ENGLAND BY 12Z MONDAY. A MOISTURE-STARVED NRN
STREAM SHORTWAVE SHOULD PRODUCE A PERIOD OF CLOUDINESS SAT
NIGHT...BUT LIKELY NOT PRODUCE ANY PRECIP. LATEST MDL SOUNDINGS
POINT TOWARD A RELATIVELY BRIGHT SUNDAY IN THE WAKE OF THIS
FEATURE WITH NEAR SEASONAL TEMPS. SPLIT FLOW REGIME ACROSS THE
LOWER 48 WILL TRANSITION TO A HIGHLY AMPLIFIED PATTERN BY EARLY
NEXT WEEK ACROSS THE LOWER 48...WITH A DEEP NEGATIVELY TILTED
TROUGH EVOLVING OVER THE EASTERN 1/3RD OF THE CONUS.

THE MODELS SEEM TO BE FORMING A CONSENSUS ON THE PESKY LOW
THAT REFUSES TO BE WELL FORECAST...LIFTING IT SLOWLY FROM FL
PANHANDLE NNEWD JUST OFF THE EAST COAST SUN-MON ALONG A LOW LEVEL
BAROCLINIC ZONE THAT MAY NOT BUDGE PAST THE GULF STREAM AS THE
FLOW ALOFT TURNS SOUTHWESTERLY/PARALLEL TO THE COASTAL FRONT.
INCREASED POPS FOR MONDAY OVER THE SE BASED ON MULTI-MODEL/WPC
BLEND. COMPLEX SFC PATTERN WITH SOME HINTS AT LOW LEVEL CAD ALONG
WITH WAA ALOFT VIA SLY FLOW COULD MAKE FOR A MESSY MIXED PTYPE
TRANSITION.

AN INTENSE TRIPLE POINT SYSTEM DEVELOPING ON DEC 23-24 WILL
LIKELY STEAL THE HEADLINES GIVEN ITS TIMING AND LARGE PORTION OF
REAL ESTATE THAT WILL BE AFFECTED. WHILE THE DETAILS REMAIN
UNCLEAR AT THIS POINT...TEMPERATURES SHOULD BE WARM ENOUGH TO
SUPPORT RAIN ON THE FRONT SIDE OF THE SYSTEM BEFORE BRISK WNW
WINDS DRIVE STRONG CAA EAST OF THE APPALACHIANS. THE TIMING OF THE
COLD/OCCLUDED FRONT WILL BE KEY FOR PRECIPITATION TRANSITION FROM
RAIN TO SNOW SHOWERS. AS THE SYSTEM SPINS UP INTO EASTERN
CANADA...THE STRONG CAA CIRCULATING THROUGH THE GREAT LAKES AND OH
VLY SHOULD LEAD TO LAKE EFFECT/UPSLOPE/WRAP AROUND SNOW SHOWERS
OVER THE WESTERN ALLEGHENIES BY CHRISTMAS DAY. A PERIOD OF STRONG
GUSTY WINDS ARE HIGHLY PROBABLE AS THE DYNAMIC SYSTEM INTENSIFIES
SHIFTING NWWD FROM NEW ENGLAND INTO ONTARIO/QUEBEC.

THE TAKE HOME MESSAGE IS THAT A VOLATILE PERIOD OF WEATHER WILL
IMPACT THE AREA THROUGH CHRISTMAS DAY WITH POTENTIAL WIND...RAIN
AND SNOW IMPACTS ALL ON THE TABLE. STAY TUNED.

&&

.AVIATION /16Z FRIDAY THROUGH TUESDAY/...
SFC TROUGH DROPPING SOUTHWARD THIS MORNING WILL GRADUALLY WASH
OUT. RIBBON OF HIGHER LOW LVL MOISTURE ALONG AND IN ADVANCE OF
THIS FEATURE WILL CONTINUE TO SUPPORT SPOTTY LGT SNOW/FZDZ ACROSS
THE ALLEGHENY MTNS THROUGH AROUND 18Z...BRINGING ICING CONCERNS
FOR AVIATION INTERESTS. IFR CONDITIONS ONGOING MAINLY AT KJST
WITH WIDESPREAD MVFR ELSEWHERE ACROSS THE CENTRAL AND NW MTNS. LOW
END MVFR STRATO CU CLOUD DECK WILL PERSIST ACROSS THE SUSQ VALLEY
THROUGH MUCH OF THE DAY.

OROGRAPHIC FORCING OF SHALLOW LYR OF MOISTURE SHOULD CONTINUE TO
PRODUCE A BIT OF LGT SNOW OR FZDZ AROUND KJST THROUGH LATE MORNING.
OTHERWISE...ARRIVAL OF DRIER AIR IN WAKE OF TROF SHOULD PRODUCE
GRADUALLY LIFTING CIGS WITH PARTIAL CLEARING LATER TODAY...ESP
WHERE WEST WIND DOWNSLOPES THE MTNS ACROSS THE SUSQ VALLEY AND SE
HALF OF CWA. NORTHWEST WINDS WILL BE AROUND 10 KTS WITH HIGHER
GUSTS.

HIGH PRESSURE BUILDS IN TONIGHT...WITH MAINLY VFR CONDITIONS. SOME
MVFR CIGS MAY DEVELOP AGAIN OVER THE NW MTNS AT KBFD. AND LIGHT
WINDS MAY PRODUCE SOME LOCAL FOG RESTRICTIONS IN SPOTS.

OUTLOOK...

SAT-SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD/LAMBERT
NEAR TERM...FITZGERALD/LAMBERT
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/STEINBUGL
AVIATION...LAMBERT/RXR




000
FXUS61 KPHI 191452
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
952 AM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE OVER THE NORTHERN GREAT LAKES WILL MOVE INTO THE OHIO
VALLEY THIS MORNING. LOW PRESSURE IS EXPECTED TO FORM OVER THE GULF
STATES LATE TONIGHT AND TRACK ACROSS GEORGIA SATURDAY. A STRONG LOW
PRESSURE SYSTEM AND COLD FRONT MAY MOVE THROUGH THE EASTERN SEABOARD ON
CHRISTMAS EVE.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MID-MORNING UPDATE...LOW CLOUDS COVER THE ENTIRE FCST AREA FROM NW
NJ AND THE POCONOS TO SRN DE. MORNING SOUNDS SHOW THE SUBSIDENCE
INVERSION BETWEEN 800 AND 850 MB WITH MOISTURE TRAPPED BELOW. THE
CLOUD LAYER IS RATHER THIN ESPECIALLY NEAR THE SRN EDGE OVER
DELVARVA AND SRN NJ. GUIDANCE INDICATES CLEARING TODAY BUT THINK
THIS MAY BE TOO OPTIMISTIC. DEC SUN WILL NOT HAVE MUCH EFFECT. HAVE
INCREASED CLOUD COVER IN THE GRIDS BUT RETAIN PARTIAL CLEARING
SOUTH. MAX TEMPS THIS AFTN WILL BE ONLY A FEW DEGS HIGHER THAN
CURRENT READINGS.

PREVIOUS DISCUSSION BELOW...
SURFACE HIGH CONTINUES TO SLIDE CLOSER TO THE REGION TODAY.
HOWEVER, LIKE LAST WEEK, THERE APPEARS TO BE ABUNDANT MOISTURE
BELOW THE INVERSION, SO DESPITE THE SYNOPTIC SCALE SUBSIDENCE,
SHOULD STILL SEE QUITE A BIT OF CLOUD COVER. WITH LITTLE CHANGE IN
THE AIR MASS, EXPECT HIGHS NEAR MAX TEMPS YESTERDAY WHICH ARE NEAR
OR JUST BELOW NORMALS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
THE BIGGEST CHANGE TONIGHT FROM THE LAST FEW NIGHTS IS THAT WITH THE
HIGH INCHING CLOSER AND THUS THE PRESSURE GRADIENT ACROSS THE REGION
DECREASING, WINDS SHOULD BE LIGHT. THOUGH WE WOULD TYPICALLY EXPECT
TO SEE CLEARING SKIES IN THIS PATTERN, WITH THE LOW LEVEL MOISTURE
LIKELY STILL IN PLACE, COULD STILL SEE QUITE A BIT OF CLOUD COVER,
ESPECIALLY OVER THE NORTHERN HALF OF THE REGION.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
MID-LEVEL FLOW THE NEXT COUPLE OF DAYS IS RATHER FLAT THOUGH A
CHANGE TO THAT PATTERN APPEARS LIKELY BY THE END OF THE WEEKEND. A
DEEP TROUGH EMERGES ACROSS THE CENTRAL U.S. BY TUESDAY AS MULTIPLE
PACIFIC NORTHWEST WAVES ROUND THE BASE OF THE TROUGH AND ACROSS OUR
REGION...WE ARE HEADING FOR A VERY UNSETTLED PERIOD BY EARLY NEXT
WEEK.

SATURDAY - SUNDAY...LOOKS MOSTLY DRY BOTH DAYS WITH HIGH PRESSURE
ANCHORED TO OUR NORTHEAST. THERE IS SOME NORTHERN STREAM ENERGY TO
CONTEND WITH LATE SATURDAY NIGHT WITH THE HELP OF A WEAK INVERTED
TROUGH OFFSHORE. THIS COMBINATION COULD TOUCH OFF A FEW SHOWERS AS
ALONG THE NORTHEASTERN NEW JERSEY COAST BUT WILL BE OF LITTLE
CONSEQUENCE. ONSHORE FLOW WILL HELP TO KEEP AMPLE LOW-LEVEL MOISTURE
STREAMING INTO THE REGION, UNDER THE SUBSIDENCE INVERSION. SATURDAY
COULD BE THE SUNNIER DAY THAN SUNDAY, BUT EACH DAY THE CONVECTIVE
TEMPERATURES LOOK TO BE REACHED SO IT MAY BE SHORT LIVED.

MONDAY - TUESDAY...ONCE THE AFOREMENTIONED SYSTEM ABOVE DEPARTS
ANOTHER, BETTER DEFINED SYSTEM MOVES OFF THE CAROLINA COAST AND OUT
TO SEA ON TUESDAY. WEAK BAROCLINIC ZONE OFF THE MID-ATLANTIC COAST
WILL ALLOW FOR AMPLE MOISTURE TO ADVECT IN FROM THE SOUTH. AS THE
WAVE OF LOW PRESSURE MOVES BY IT WILL TAP INTO THE MOISTURE FEED
ALLOWING FOR BETTER CHANCES OF PRECIPITATION. CONTINUED ONSHORE FLOW
AHEAD OF THE SYSTEM WILL ALLOW FOR A WARMING LOW-LEVEL THERMAL
PROFILE SO ANY PRECIPITATION WILL BE LIQUID WITH SOME MIXING
POSSIBLE IN THE FAR NORTHWESTERN ZONES. IT IS ENTIRELY POSSIBLE THAT
A WEAK CAD SETUP OCCURS LATE MONDAY NIGHT WITH A NORTHERLY BOUNDARY
LAYER AGEOSTROPHIC WIND COMPONENT. MODELS HAVE BEEN KNOWN TO WARM
THE SURFACE LAYER TOO FAST WITH A RATHER LARGE NEW ENGLAND HIGH
PRESSURE IN PLACE, OR THEY PUSH THE HIGH OUT FASTER ALLOWING A
SOUTHEAST RETURN FLOW. EITHER WAY IT COULD BE A MESSY TUESDAY
MORNING COMMUTE ACROSS OUR NORTHWEST ZONES. SYSTEM MOVES OFF TOWARDS
THE NORTHEAST ON TUESDAY, WITH RAIN STILL ONGOING, BUT WE ARE
GEARING UP FOR THE BIGGER EVENT ON CHRISTMAS EVE.

WEDNESDAY...STILL WATCHING A LARGE LOW PRESSURE FORM TO OUR WEST AND
TRACK INTO THE GREAT LAKES REGION ON WEDNESDAY. THIS WOULD KEEP OUR
REGION UNDER A WARMING THERMAL PROFILE WITH A LOT OF MOISTURE TO
WORK WITH...AN ALL LIQUID EVENT IS EXPECTED AT THIS POINT. GUIDANCE
CONTINUES TO SHOW A WEAKER SECONDARY DEVELOPMENT ALONG A TRIPLE
POINT OVER OUR REGION DURING THE DAY. THIS WOULD HELP TO INTENSIFY
RAINFALL AMOUNTS AND ENHANCE THE LOW-LEVEL PRESSURE GRADIENT. HEAVY
RAIN WITH STRONG WINDS ARE EXPECTED SO IT IS ENTIRELY POSSIBLE WE
ARE LOOKING AT ANOTHER MULTIPLE HEADLINE EVENT. COASTAL FLOODING
COULD ALSO BECOME AN ISSUE WITH THE STRONGER ONSHORE WINDS DURING
WEDNESDAY`S HIGH TIDE. HAVE GONE WITH CATEGORICAL POPS FOR THAIS
TIMEFRAME. WE WILL CONTINUE TO HAVE WORDING IN THE HWO FOR THIS
EVENT. LOOKS LIKE RUDOLPH AND THE OTHER REINDEER WILL HAVE THEIR
WORK CUT OUT FOR THEM THIS CHRISTMAS EVE.

&&

.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

LOW-END VFR CIGS CONTINUE AT ALL TAF SITES THIS MORNING. NO
PROBLEMS WITH VSBYS. A FEW NW WINDS GUSTS ARE POSSIBLE TODAY BUT
THIS GUSTINESS IS LOOKING LESS LIKELY WITH TIME.

MOSTLY VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD. THERE
SHOULD BE PERSISTENT CLOUDS BETWEEN 3000 AND 5000 FT AGL FOR MUCH OF
THE DAY, SO COULD SEE LOCALIZED MVFR CEILINGS RIGHT AT 3000 FT, BUT
MOSTLY CEILINGS SHOULD BE BETWEEN 3500 AND 4000 FT. NORTHWESTERLY
WINDS MAY GUST AT TIMES TO 20KT THROUGH EARLY THIS AFTERNOON, BUT BY
TONIGHT SHOULD BE LESS THAN 10KT.

OUTLOOK...
SATURDAY - SUNDAY...VFR. NORTH-NORTHEAST WINDS EXPECTED. CIGS COULD BE
LOWERING THROUGHOUT THE DAY

MONDAY - TUESDAY...SUB-VFR EXPECTED WITH SCATTERED RAIN/SNOW
SHOWERS, BECOMING ALL RAIN BY TUESDAY.

&&

.MARINE...
WINDS AND SEAS SHOULD STAY BELOW SCA CRITERIA. HOWEVER, GUSTS NEAR
OR JUST ABOVE 20KT WILL BE POSSIBLE THROUGH THIS EVENING.

OUTLOOK...
SATURDAY - SUNDAY...SUB-SCA EXPECTED FOR THE MOST PART. SEAS REMAIN
AROUND 3 TO 4 FEET.  CONFIDENCE: AVERAGE TO SLIGHTLY BELOW AVERAGE.

MONDAY - TUESDAY...SCA CONDITIONS SHOULD PRESENT THEMSELVES LATER ON MONDAY
UNDER A STRENGTHENING EASTERLY FLOW AND BUILDING SEAS. CONFIDENCE:
AVERAGE.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...GIGI
NEAR TERM...AMC/JOHNSON
SHORT TERM...JOHNSON
LONG TERM...HEAVENER
AVIATION...AMC/HEAVENER/JOHNSON
MARINE...HEAVENER/JOHNSON







000
FXUS61 KPHI 191452
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
952 AM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE OVER THE NORTHERN GREAT LAKES WILL MOVE INTO THE OHIO
VALLEY THIS MORNING. LOW PRESSURE IS EXPECTED TO FORM OVER THE GULF
STATES LATE TONIGHT AND TRACK ACROSS GEORGIA SATURDAY. A STRONG LOW
PRESSURE SYSTEM AND COLD FRONT MAY MOVE THROUGH THE EASTERN SEABOARD ON
CHRISTMAS EVE.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MID-MORNING UPDATE...LOW CLOUDS COVER THE ENTIRE FCST AREA FROM NW
NJ AND THE POCONOS TO SRN DE. MORNING SOUNDS SHOW THE SUBSIDENCE
INVERSION BETWEEN 800 AND 850 MB WITH MOISTURE TRAPPED BELOW. THE
CLOUD LAYER IS RATHER THIN ESPECIALLY NEAR THE SRN EDGE OVER
DELVARVA AND SRN NJ. GUIDANCE INDICATES CLEARING TODAY BUT THINK
THIS MAY BE TOO OPTIMISTIC. DEC SUN WILL NOT HAVE MUCH EFFECT. HAVE
INCREASED CLOUD COVER IN THE GRIDS BUT RETAIN PARTIAL CLEARING
SOUTH. MAX TEMPS THIS AFTN WILL BE ONLY A FEW DEGS HIGHER THAN
CURRENT READINGS.

PREVIOUS DISCUSSION BELOW...
SURFACE HIGH CONTINUES TO SLIDE CLOSER TO THE REGION TODAY.
HOWEVER, LIKE LAST WEEK, THERE APPEARS TO BE ABUNDANT MOISTURE
BELOW THE INVERSION, SO DESPITE THE SYNOPTIC SCALE SUBSIDENCE,
SHOULD STILL SEE QUITE A BIT OF CLOUD COVER. WITH LITTLE CHANGE IN
THE AIR MASS, EXPECT HIGHS NEAR MAX TEMPS YESTERDAY WHICH ARE NEAR
OR JUST BELOW NORMALS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
THE BIGGEST CHANGE TONIGHT FROM THE LAST FEW NIGHTS IS THAT WITH THE
HIGH INCHING CLOSER AND THUS THE PRESSURE GRADIENT ACROSS THE REGION
DECREASING, WINDS SHOULD BE LIGHT. THOUGH WE WOULD TYPICALLY EXPECT
TO SEE CLEARING SKIES IN THIS PATTERN, WITH THE LOW LEVEL MOISTURE
LIKELY STILL IN PLACE, COULD STILL SEE QUITE A BIT OF CLOUD COVER,
ESPECIALLY OVER THE NORTHERN HALF OF THE REGION.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
MID-LEVEL FLOW THE NEXT COUPLE OF DAYS IS RATHER FLAT THOUGH A
CHANGE TO THAT PATTERN APPEARS LIKELY BY THE END OF THE WEEKEND. A
DEEP TROUGH EMERGES ACROSS THE CENTRAL U.S. BY TUESDAY AS MULTIPLE
PACIFIC NORTHWEST WAVES ROUND THE BASE OF THE TROUGH AND ACROSS OUR
REGION...WE ARE HEADING FOR A VERY UNSETTLED PERIOD BY EARLY NEXT
WEEK.

SATURDAY - SUNDAY...LOOKS MOSTLY DRY BOTH DAYS WITH HIGH PRESSURE
ANCHORED TO OUR NORTHEAST. THERE IS SOME NORTHERN STREAM ENERGY TO
CONTEND WITH LATE SATURDAY NIGHT WITH THE HELP OF A WEAK INVERTED
TROUGH OFFSHORE. THIS COMBINATION COULD TOUCH OFF A FEW SHOWERS AS
ALONG THE NORTHEASTERN NEW JERSEY COAST BUT WILL BE OF LITTLE
CONSEQUENCE. ONSHORE FLOW WILL HELP TO KEEP AMPLE LOW-LEVEL MOISTURE
STREAMING INTO THE REGION, UNDER THE SUBSIDENCE INVERSION. SATURDAY
COULD BE THE SUNNIER DAY THAN SUNDAY, BUT EACH DAY THE CONVECTIVE
TEMPERATURES LOOK TO BE REACHED SO IT MAY BE SHORT LIVED.

MONDAY - TUESDAY...ONCE THE AFOREMENTIONED SYSTEM ABOVE DEPARTS
ANOTHER, BETTER DEFINED SYSTEM MOVES OFF THE CAROLINA COAST AND OUT
TO SEA ON TUESDAY. WEAK BAROCLINIC ZONE OFF THE MID-ATLANTIC COAST
WILL ALLOW FOR AMPLE MOISTURE TO ADVECT IN FROM THE SOUTH. AS THE
WAVE OF LOW PRESSURE MOVES BY IT WILL TAP INTO THE MOISTURE FEED
ALLOWING FOR BETTER CHANCES OF PRECIPITATION. CONTINUED ONSHORE FLOW
AHEAD OF THE SYSTEM WILL ALLOW FOR A WARMING LOW-LEVEL THERMAL
PROFILE SO ANY PRECIPITATION WILL BE LIQUID WITH SOME MIXING
POSSIBLE IN THE FAR NORTHWESTERN ZONES. IT IS ENTIRELY POSSIBLE THAT
A WEAK CAD SETUP OCCURS LATE MONDAY NIGHT WITH A NORTHERLY BOUNDARY
LAYER AGEOSTROPHIC WIND COMPONENT. MODELS HAVE BEEN KNOWN TO WARM
THE SURFACE LAYER TOO FAST WITH A RATHER LARGE NEW ENGLAND HIGH
PRESSURE IN PLACE, OR THEY PUSH THE HIGH OUT FASTER ALLOWING A
SOUTHEAST RETURN FLOW. EITHER WAY IT COULD BE A MESSY TUESDAY
MORNING COMMUTE ACROSS OUR NORTHWEST ZONES. SYSTEM MOVES OFF TOWARDS
THE NORTHEAST ON TUESDAY, WITH RAIN STILL ONGOING, BUT WE ARE
GEARING UP FOR THE BIGGER EVENT ON CHRISTMAS EVE.

WEDNESDAY...STILL WATCHING A LARGE LOW PRESSURE FORM TO OUR WEST AND
TRACK INTO THE GREAT LAKES REGION ON WEDNESDAY. THIS WOULD KEEP OUR
REGION UNDER A WARMING THERMAL PROFILE WITH A LOT OF MOISTURE TO
WORK WITH...AN ALL LIQUID EVENT IS EXPECTED AT THIS POINT. GUIDANCE
CONTINUES TO SHOW A WEAKER SECONDARY DEVELOPMENT ALONG A TRIPLE
POINT OVER OUR REGION DURING THE DAY. THIS WOULD HELP TO INTENSIFY
RAINFALL AMOUNTS AND ENHANCE THE LOW-LEVEL PRESSURE GRADIENT. HEAVY
RAIN WITH STRONG WINDS ARE EXPECTED SO IT IS ENTIRELY POSSIBLE WE
ARE LOOKING AT ANOTHER MULTIPLE HEADLINE EVENT. COASTAL FLOODING
COULD ALSO BECOME AN ISSUE WITH THE STRONGER ONSHORE WINDS DURING
WEDNESDAY`S HIGH TIDE. HAVE GONE WITH CATEGORICAL POPS FOR THAIS
TIMEFRAME. WE WILL CONTINUE TO HAVE WORDING IN THE HWO FOR THIS
EVENT. LOOKS LIKE RUDOLPH AND THE OTHER REINDEER WILL HAVE THEIR
WORK CUT OUT FOR THEM THIS CHRISTMAS EVE.

&&

.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

LOW-END VFR CIGS CONTINUE AT ALL TAF SITES THIS MORNING. NO
PROBLEMS WITH VSBYS. A FEW NW WINDS GUSTS ARE POSSIBLE TODAY BUT
THIS GUSTINESS IS LOOKING LESS LIKELY WITH TIME.

MOSTLY VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD. THERE
SHOULD BE PERSISTENT CLOUDS BETWEEN 3000 AND 5000 FT AGL FOR MUCH OF
THE DAY, SO COULD SEE LOCALIZED MVFR CEILINGS RIGHT AT 3000 FT, BUT
MOSTLY CEILINGS SHOULD BE BETWEEN 3500 AND 4000 FT. NORTHWESTERLY
WINDS MAY GUST AT TIMES TO 20KT THROUGH EARLY THIS AFTERNOON, BUT BY
TONIGHT SHOULD BE LESS THAN 10KT.

OUTLOOK...
SATURDAY - SUNDAY...VFR. NORTH-NORTHEAST WINDS EXPECTED. CIGS COULD BE
LOWERING THROUGHOUT THE DAY

MONDAY - TUESDAY...SUB-VFR EXPECTED WITH SCATTERED RAIN/SNOW
SHOWERS, BECOMING ALL RAIN BY TUESDAY.

&&

.MARINE...
WINDS AND SEAS SHOULD STAY BELOW SCA CRITERIA. HOWEVER, GUSTS NEAR
OR JUST ABOVE 20KT WILL BE POSSIBLE THROUGH THIS EVENING.

OUTLOOK...
SATURDAY - SUNDAY...SUB-SCA EXPECTED FOR THE MOST PART. SEAS REMAIN
AROUND 3 TO 4 FEET.  CONFIDENCE: AVERAGE TO SLIGHTLY BELOW AVERAGE.

MONDAY - TUESDAY...SCA CONDITIONS SHOULD PRESENT THEMSELVES LATER ON MONDAY
UNDER A STRENGTHENING EASTERLY FLOW AND BUILDING SEAS. CONFIDENCE:
AVERAGE.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...GIGI
NEAR TERM...AMC/JOHNSON
SHORT TERM...JOHNSON
LONG TERM...HEAVENER
AVIATION...AMC/HEAVENER/JOHNSON
MARINE...HEAVENER/JOHNSON






000
FXUS61 KPBZ 191416
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
916 AM EST FRI DEC 19 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND...THOUGH
CLOUDS WILL REMAIN.

&&

.NEAR TERM /THROUGH TONIGHT/...
FINE LINE ON RADAR IS THE BACK EDGE OF FREEZING DRIZZLE AND
FLURRIES WITH SURFACE TROUGH AND BACK EDGE OF STRETCHED VORT
BEHIND SHORTWAVE EXITING EAST. ALLOWED ADVISORIES TO EXPIRE AS
RADAR TRENDS AND SURFACE OBS SHOW DIMINISHING TREND TO PRECIP AND
HAVE ISSUED SPS TO COVER REMAINING PATCHY PRECIP. FORECAST
SOUNDINGS SHOW CLOUDS MAY HOLD IN THROUGH TONIGHT SO HAVE ADJUSTED
SKY GRIDS UP. NO CHANGE TO PREVIOUS TEMPERATURE.


&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
HIGH PRESSURE WILL REIGN OVER THE FORECAST AREA THROUGH THE
WEEKEND. A WEAK OPEN WAVE TRIES TO SKIRT THE SRN EXTENT OF THE SFC
HIGH SAT AFTERNOON...BUT MODELS CONTINUE TO TREND IT FURTHER SOUTH
WELL OUT OF OUR REGION. AFTER LARGELY ZONAL FLOW ALOFT THROUGH
SUNDAY THE UPPER LEVEL PATTERN FAVORS SWRLY FLOW ON THE BACKSIDE
OF THE SFC HIGH. THIS WILL WORK TO DRIVE WARMER TEMPS INTO THE
FORECAST AREA WITH HIGHS DRIVING ABOVE AVERAGE HEADING INTO EARLY
NEXT WEEK.
TAX

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
WHILE THE MODELS AGREE ON A DEEPENING UPPER LEVEL TROUGH TO CLOSE
OFF OVER THE GREAT LAKES THROUGH THE PERIOD THE DETAILS OF HOW
THIS EXACTLY UNFOLDS WILL BE CRITICAL. BY MONDAY SOUTHERN STREAM
SHORTWAVE AHEAD OF MAIN NORTHERN STREAM UPPER TROUGH DIGGING INTO
THE NORTHERN PLAINS WILL PRODUCE LOW PRESSURE ACROSS THE CAROLINAS
MOVING OFF SHORE OF THE EAST COAST. THE SOUTHEAST RIDGES MAY BE
BRUSHED BY LIGHT RAIN FROM THIS SYSTEM. NEXT UP IS DEEPENING LOW
PRESSURE OVER THE OHIO VALLEY AHEAD OF SHARPLY DIGGING UPPER
TROUGH AND CLOSED LOW MOVING INTO THE WESTERN GREAT LAKES. UPPER
OHIO VALLEY LOOKS TO BE ON THE WARM SIDE OF THE SYSTEM TUESDAY
INTO WEDNESDAY WITH RAIN...FOLLOWED BY STRONG COLD FRONT AND COLD
ADVECTION LATER WEDNESDAY NIGHT AND THURSDAY WITH SNOW SHOWERS.
WITH SUCH A STRONG SYSTEM ALOFT AND FAST DEEPENING LOW PRESSURE AT
THE SURFACE TIMING OF COLD AIR AND EXACT TRACK WILL LIKELY CHANGE
AS WE GET CLOSER TO CHRISTMAS. ALL IN ALL PREVIOUS FORECAST IS
LITTLE CHANGED WITH ONLY MINOR ADJUSTMENTS BASED ON NEWEST WPC
EXTENDED PROGS.

&&

.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
MVFR TO ISOLATED IFR CIGS WILL IMPROVE TO MVFR THIS AFTERNOON AND
CONTINUE TONIGHT.


OUTLOOK.../FRIDAY NIGHT THROUGH TUESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$









000
FXUS61 KPBZ 191416
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
916 AM EST FRI DEC 19 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND...THOUGH
CLOUDS WILL REMAIN.

&&

.NEAR TERM /THROUGH TONIGHT/...
FINE LINE ON RADAR IS THE BACK EDGE OF FREEZING DRIZZLE AND
FLURRIES WITH SURFACE TROUGH AND BACK EDGE OF STRETCHED VORT
BEHIND SHORTWAVE EXITING EAST. ALLOWED ADVISORIES TO EXPIRE AS
RADAR TRENDS AND SURFACE OBS SHOW DIMINISHING TREND TO PRECIP AND
HAVE ISSUED SPS TO COVER REMAINING PATCHY PRECIP. FORECAST
SOUNDINGS SHOW CLOUDS MAY HOLD IN THROUGH TONIGHT SO HAVE ADJUSTED
SKY GRIDS UP. NO CHANGE TO PREVIOUS TEMPERATURE.


&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
HIGH PRESSURE WILL REIGN OVER THE FORECAST AREA THROUGH THE
WEEKEND. A WEAK OPEN WAVE TRIES TO SKIRT THE SRN EXTENT OF THE SFC
HIGH SAT AFTERNOON...BUT MODELS CONTINUE TO TREND IT FURTHER SOUTH
WELL OUT OF OUR REGION. AFTER LARGELY ZONAL FLOW ALOFT THROUGH
SUNDAY THE UPPER LEVEL PATTERN FAVORS SWRLY FLOW ON THE BACKSIDE
OF THE SFC HIGH. THIS WILL WORK TO DRIVE WARMER TEMPS INTO THE
FORECAST AREA WITH HIGHS DRIVING ABOVE AVERAGE HEADING INTO EARLY
NEXT WEEK.
TAX

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
WHILE THE MODELS AGREE ON A DEEPENING UPPER LEVEL TROUGH TO CLOSE
OFF OVER THE GREAT LAKES THROUGH THE PERIOD THE DETAILS OF HOW
THIS EXACTLY UNFOLDS WILL BE CRITICAL. BY MONDAY SOUTHERN STREAM
SHORTWAVE AHEAD OF MAIN NORTHERN STREAM UPPER TROUGH DIGGING INTO
THE NORTHERN PLAINS WILL PRODUCE LOW PRESSURE ACROSS THE CAROLINAS
MOVING OFF SHORE OF THE EAST COAST. THE SOUTHEAST RIDGES MAY BE
BRUSHED BY LIGHT RAIN FROM THIS SYSTEM. NEXT UP IS DEEPENING LOW
PRESSURE OVER THE OHIO VALLEY AHEAD OF SHARPLY DIGGING UPPER
TROUGH AND CLOSED LOW MOVING INTO THE WESTERN GREAT LAKES. UPPER
OHIO VALLEY LOOKS TO BE ON THE WARM SIDE OF THE SYSTEM TUESDAY
INTO WEDNESDAY WITH RAIN...FOLLOWED BY STRONG COLD FRONT AND COLD
ADVECTION LATER WEDNESDAY NIGHT AND THURSDAY WITH SNOW SHOWERS.
WITH SUCH A STRONG SYSTEM ALOFT AND FAST DEEPENING LOW PRESSURE AT
THE SURFACE TIMING OF COLD AIR AND EXACT TRACK WILL LIKELY CHANGE
AS WE GET CLOSER TO CHRISTMAS. ALL IN ALL PREVIOUS FORECAST IS
LITTLE CHANGED WITH ONLY MINOR ADJUSTMENTS BASED ON NEWEST WPC
EXTENDED PROGS.

&&

.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
MVFR TO ISOLATED IFR CIGS WILL IMPROVE TO MVFR THIS AFTERNOON AND
CONTINUE TONIGHT.


OUTLOOK.../FRIDAY NIGHT THROUGH TUESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$









000
FXUS61 KPBZ 191416
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
916 AM EST FRI DEC 19 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND...THOUGH
CLOUDS WILL REMAIN.

&&

.NEAR TERM /THROUGH TONIGHT/...
FINE LINE ON RADAR IS THE BACK EDGE OF FREEZING DRIZZLE AND
FLURRIES WITH SURFACE TROUGH AND BACK EDGE OF STRETCHED VORT
BEHIND SHORTWAVE EXITING EAST. ALLOWED ADVISORIES TO EXPIRE AS
RADAR TRENDS AND SURFACE OBS SHOW DIMINISHING TREND TO PRECIP AND
HAVE ISSUED SPS TO COVER REMAINING PATCHY PRECIP. FORECAST
SOUNDINGS SHOW CLOUDS MAY HOLD IN THROUGH TONIGHT SO HAVE ADJUSTED
SKY GRIDS UP. NO CHANGE TO PREVIOUS TEMPERATURE.


&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
HIGH PRESSURE WILL REIGN OVER THE FORECAST AREA THROUGH THE
WEEKEND. A WEAK OPEN WAVE TRIES TO SKIRT THE SRN EXTENT OF THE SFC
HIGH SAT AFTERNOON...BUT MODELS CONTINUE TO TREND IT FURTHER SOUTH
WELL OUT OF OUR REGION. AFTER LARGELY ZONAL FLOW ALOFT THROUGH
SUNDAY THE UPPER LEVEL PATTERN FAVORS SWRLY FLOW ON THE BACKSIDE
OF THE SFC HIGH. THIS WILL WORK TO DRIVE WARMER TEMPS INTO THE
FORECAST AREA WITH HIGHS DRIVING ABOVE AVERAGE HEADING INTO EARLY
NEXT WEEK.
TAX

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
WHILE THE MODELS AGREE ON A DEEPENING UPPER LEVEL TROUGH TO CLOSE
OFF OVER THE GREAT LAKES THROUGH THE PERIOD THE DETAILS OF HOW
THIS EXACTLY UNFOLDS WILL BE CRITICAL. BY MONDAY SOUTHERN STREAM
SHORTWAVE AHEAD OF MAIN NORTHERN STREAM UPPER TROUGH DIGGING INTO
THE NORTHERN PLAINS WILL PRODUCE LOW PRESSURE ACROSS THE CAROLINAS
MOVING OFF SHORE OF THE EAST COAST. THE SOUTHEAST RIDGES MAY BE
BRUSHED BY LIGHT RAIN FROM THIS SYSTEM. NEXT UP IS DEEPENING LOW
PRESSURE OVER THE OHIO VALLEY AHEAD OF SHARPLY DIGGING UPPER
TROUGH AND CLOSED LOW MOVING INTO THE WESTERN GREAT LAKES. UPPER
OHIO VALLEY LOOKS TO BE ON THE WARM SIDE OF THE SYSTEM TUESDAY
INTO WEDNESDAY WITH RAIN...FOLLOWED BY STRONG COLD FRONT AND COLD
ADVECTION LATER WEDNESDAY NIGHT AND THURSDAY WITH SNOW SHOWERS.
WITH SUCH A STRONG SYSTEM ALOFT AND FAST DEEPENING LOW PRESSURE AT
THE SURFACE TIMING OF COLD AIR AND EXACT TRACK WILL LIKELY CHANGE
AS WE GET CLOSER TO CHRISTMAS. ALL IN ALL PREVIOUS FORECAST IS
LITTLE CHANGED WITH ONLY MINOR ADJUSTMENTS BASED ON NEWEST WPC
EXTENDED PROGS.

&&

.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
MVFR TO ISOLATED IFR CIGS WILL IMPROVE TO MVFR THIS AFTERNOON AND
CONTINUE TONIGHT.


OUTLOOK.../FRIDAY NIGHT THROUGH TUESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$









000
FXUS61 KPBZ 191416
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
916 AM EST FRI DEC 19 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND...THOUGH
CLOUDS WILL REMAIN.

&&

.NEAR TERM /THROUGH TONIGHT/...
FINE LINE ON RADAR IS THE BACK EDGE OF FREEZING DRIZZLE AND
FLURRIES WITH SURFACE TROUGH AND BACK EDGE OF STRETCHED VORT
BEHIND SHORTWAVE EXITING EAST. ALLOWED ADVISORIES TO EXPIRE AS
RADAR TRENDS AND SURFACE OBS SHOW DIMINISHING TREND TO PRECIP AND
HAVE ISSUED SPS TO COVER REMAINING PATCHY PRECIP. FORECAST
SOUNDINGS SHOW CLOUDS MAY HOLD IN THROUGH TONIGHT SO HAVE ADJUSTED
SKY GRIDS UP. NO CHANGE TO PREVIOUS TEMPERATURE.


&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
HIGH PRESSURE WILL REIGN OVER THE FORECAST AREA THROUGH THE
WEEKEND. A WEAK OPEN WAVE TRIES TO SKIRT THE SRN EXTENT OF THE SFC
HIGH SAT AFTERNOON...BUT MODELS CONTINUE TO TREND IT FURTHER SOUTH
WELL OUT OF OUR REGION. AFTER LARGELY ZONAL FLOW ALOFT THROUGH
SUNDAY THE UPPER LEVEL PATTERN FAVORS SWRLY FLOW ON THE BACKSIDE
OF THE SFC HIGH. THIS WILL WORK TO DRIVE WARMER TEMPS INTO THE
FORECAST AREA WITH HIGHS DRIVING ABOVE AVERAGE HEADING INTO EARLY
NEXT WEEK.
TAX

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
WHILE THE MODELS AGREE ON A DEEPENING UPPER LEVEL TROUGH TO CLOSE
OFF OVER THE GREAT LAKES THROUGH THE PERIOD THE DETAILS OF HOW
THIS EXACTLY UNFOLDS WILL BE CRITICAL. BY MONDAY SOUTHERN STREAM
SHORTWAVE AHEAD OF MAIN NORTHERN STREAM UPPER TROUGH DIGGING INTO
THE NORTHERN PLAINS WILL PRODUCE LOW PRESSURE ACROSS THE CAROLINAS
MOVING OFF SHORE OF THE EAST COAST. THE SOUTHEAST RIDGES MAY BE
BRUSHED BY LIGHT RAIN FROM THIS SYSTEM. NEXT UP IS DEEPENING LOW
PRESSURE OVER THE OHIO VALLEY AHEAD OF SHARPLY DIGGING UPPER
TROUGH AND CLOSED LOW MOVING INTO THE WESTERN GREAT LAKES. UPPER
OHIO VALLEY LOOKS TO BE ON THE WARM SIDE OF THE SYSTEM TUESDAY
INTO WEDNESDAY WITH RAIN...FOLLOWED BY STRONG COLD FRONT AND COLD
ADVECTION LATER WEDNESDAY NIGHT AND THURSDAY WITH SNOW SHOWERS.
WITH SUCH A STRONG SYSTEM ALOFT AND FAST DEEPENING LOW PRESSURE AT
THE SURFACE TIMING OF COLD AIR AND EXACT TRACK WILL LIKELY CHANGE
AS WE GET CLOSER TO CHRISTMAS. ALL IN ALL PREVIOUS FORECAST IS
LITTLE CHANGED WITH ONLY MINOR ADJUSTMENTS BASED ON NEWEST WPC
EXTENDED PROGS.

&&

.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
MVFR TO ISOLATED IFR CIGS WILL IMPROVE TO MVFR THIS AFTERNOON AND
CONTINUE TONIGHT.


OUTLOOK.../FRIDAY NIGHT THROUGH TUESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$









000
FXUS61 KCTP 191252
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
752 AM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE OVER THE GREAT LAKES WILL SLIDE EAST INTO
PENNSYLVANIA THIS WEEKEND. A DEEP UPPER TROUGH AND ASSOCIATED SFC
LOW WILL LIFT NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE
OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LINEAR FEATURE ON RADAR LOOP RUNNING FROM KYNG TO KDUJ AT 11Z
APPEARS TO BE SFC TROUGH...WHICH IS PROGGED BY NR TERM MDLS TO
WASH OUT AS IT PRESSES SOUTH THIS MORNING. RIBBON OF HIGHER LOW
LVL MOISTURE ALONG AND IN ADVANCE OF THIS FEATURE HAS BEEN
SUPPORTING SPOTTY LGT SNOW/FZDZ ACROSS THE ALLEGHENY MTNS THIS
MORNING. WINT WX ADV...WHICH HAS BEEN IN EFFECT ACROSS THE N
MTNS...WILL EXPIRE AT 12Z AS FOCUS OF FREEZING PRECIP SHIFTS
SOUTH INTO THE LAUREL HIGHLANDS.

OROGRAPHIC FORCING OF SHALLOW LYR OF MOISTURE SHOULD CONTINUE TO
PRODUCE A BIT OF LGT SNOW OR FZDZ ACROSS CAMBRIA/SOMERSET
COUNTIES THRU ARND MIDDAY. HOWEVER...GIVEN THE VERY LGT NATURE OF
THE PRECIP AND THAT SOME IS FALLING AS SNOW...HAVE OPTED TO COVER
WITH AN SPS RATHER THAN A WSW. SFC OBS HAVE BEEN INDICATING BOTH
-SHSN AND -FZDZ AND MDL SOUNDINGS INDICATE BORDERLINE CLOUD TOP
TEMPS OF ARND -10C...SO WILL CONTINUE TO FCST SCT -SHSN AND PATCHY
-FZDZ OVR THE LAUREL HIGHLANDS THIS AM.

OTHERWISE...ARRIVAL OF DRIER AIR IN WAKE OF TROF SHOULD PRODUCE
PARTIAL CLEARING LATER TODAY...ESP WHERE WEST WIND DOWNSLOPES THE
MTNS ACROSS THE SUSQ VALLEY.

MAX TEMPS SHOULD BE SIMILAR TO THURSDAY...WITH U20S OVR THE
HIGHEST TERRAIN OF THE ALLEGHENIES...TO THE U30S ACROSS THE LOWER
SUSQ VALLEY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
HIGH PRESSURE AND ASSOC DRIER AIR MASS WILL BUILD IN FROM THE GRT
LKS TONIGHT...PROVIDING THE AREA WITH FAIR WX. FOR MUCH OF CENTRAL
PA...TONIGHT SHOULD FEATURE MCLEAR SKIES. HOWEVER...LOW LVL
MOISTURE TRAPPED BENEATH INVERSION MAY RESULT IN PERSISTENT
STRATOCU ACROSS THE LAUREL HIGHLANDS THIS EVENING.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS INTO THE REGION ON SATURDAY.
HOWEVER...ALL MDL DATA SUPPORTS A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS IN THE 30S.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE WILL SHIFT SLOWLY EASTWARD FROM THE GREAT LAKES
INTO NORTHERN NEW ENGLAND BY 12Z MONDAY. A MOISTURE-STARVED NRN
STREAM SHORTWAVE SHOULD PRODUCE A PERIOD OF CLOUDINESS SAT
NIGHT...BUT LIKELY NOT PRODUCE ANY PRECIP. LATEST MDL SOUNDINGS
POINT TOWARD A RELATIVELY BRIGHT SUNDAY IN THE WAKE OF THIS
FEATURE WITH NEAR SEASONAL TEMPS. SPLIT FLOW REGIME ACROSS THE
LOWER 48 WILL TRANSITION TO A HIGHLY AMPLIFIED PATTERN BY EARLY
NEXT WEEK ACROSS THE LOWER 48...WITH A DEEP NEGATIVELY TILTED
TROUGH EVOLVING OVER THE EASTERN 1/3RD OF THE CONUS.

THE MODELS SEEM TO BE FORMING A CONSENSUS ON THE PESKY LOW
THAT REFUSES TO BE WELL FORECAST...LIFTING IT SLOWLY FROM FL
PANHANDLE NNEWD JUST OFF THE EAST COAST SUN-MON ALONG A LOW LEVEL
BAROCLINIC ZONE THAT MAY NOT BUDGE PAST THE GULF STREAM AS THE
FLOW ALOFT TURNS SOUTHWESTERLY/PARALLEL TO THE COASTAL FRONT.
INCREASED POPS FOR MONDAY OVER THE SE BASED ON MULTI-MODEL/WPC
BLEND. COMPLEX SFC PATTERN WITH SOME HINTS AT LOW LEVEL CAD ALONG
WITH WAA ALOFT VIA SLY FLOW COULD MAKE FOR A MESSY MIXED PTYPE
TRANSITION.

AN INTENSE TRIPLE POINT SYSTEM DEVELOPING ON DEC 23-24 WILL
LIKELY STEAL THE HEADLINES GIVEN ITS TIMING AND LARGE PORTION OF
REAL ESTATE THAT WILL BE AFFECTED. WHILE THE DETAILS REMAIN
UNCLEAR AT THIS POINT...TEMPERATURES SHOULD BE WARM ENOUGH TO
SUPPORT RAIN ON THE FRONT SIDE OF THE SYSTEM BEFORE BRISK WNW
WINDS DRIVE STRONG CAA EAST OF THE APPALACHIANS. THE TIMING OF THE
COLD/OCCLUDED FRONT WILL BE KEY FOR PRECIPITATION TRANSITION FROM
RAIN TO SNOW SHOWERS. AS THE SYSTEM SPINS UP INTO EASTERN
CANADA...THE STRONG CAA CIRCULATING THROUGH THE GREAT LAKES AND OH
VLY SHOULD LEAD TO LAKE EFFECT/UPSLOPE/WRAP AROUND SNOW SHOWERS
OVER THE WESTERN ALLEGHENIES BY CHRISTMAS DAY. A PERIOD OF STRONG
GUSTY WINDS ARE HIGHLY PROBABLE AS THE DYNAMIC SYSTEM INTENSIFIES
SHIFTING NWWD FROM NEW ENGLAND INTO ONTARIO/QUEBEC.

THE TAKE HOME MESSAGE IS THAT A VOLATILE PERIOD OF WEATHER WILL
IMPACT THE AREA THROUGH CHRISTMAS DAY WITH POTENTIAL WIND...RAIN
AND SNOW IMPACTS ALL ON THE TABLE. STAY TUNED.

&&

.AVIATION /13Z FRIDAY THROUGH TUESDAY/...
SFC TROUGH DROPPING SOUTHWARD THIS MORNING WILL GRADUALLY WASH
OUT. RIBBON OF HIGHER LOW LVL MOISTURE ALONG AND IN ADVANCE OF
THIS FEATURE HAS BEEN SUPPORTING SPOTTY LGT SNOW/FZDZ ACROSS THE
ALLEGHENY MTNS THIS MORNING...BRINGING ICING CONCERNS FOR
AVIATION INTERESTS. IFR CONDITIONS ONGOING AT KBFD-KJST WITH
WIDESPREAD MVFR ELSEWHERE.

OROGRAPHIC FORCING OF SHALLOW LYR OF MOISTURE SHOULD CONTINUE TO
PRODUCE A BIT OF LGT SNOW OR FZDZ AROUND KJST THROUGH LATE MORNING.
OTHERWISE...ARRIVAL OF DRIER AIR IN WAKE OF TROF SHOULD PRODUCE
GRADUALLY LIFTING CIGS WITH PARTIAL CLEARING LATER TODAY...ESP
WHERE WEST WIND DOWNSLOPES THE MTNS ACROSS THE SUSQ VALLEY AND SE
HALF OF CWA. NORTHWEST WINDS WILL BE AROUND 10 KTS WITH HIGHER
GUSTS.

HIGH PRESSURE BUILDS IN TONIGHT...WITH MAINLY VFR CONDITIONS. SOME
MVFR CIGS MAY DEVELOP AGAIN OVER THE NW MTNS AT KBFD. AND LIGHT
WINDS MAY PRODUCE SOME LOCAL FOG RESTRICTIONS IN SPOTS.

OUTLOOK...

SAT-SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE. BECOMING BREEZY.

TUE...LOW CIGS WITH RAIN LIKELY. BREEZY.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/STEINBUGL
AVIATION...RXR




000
FXUS61 KCTP 191130
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
630 AM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE OVER THE GREAT LAKES WILL SLIDE EAST INTO
PENNSYLVANIA THIS WEEKEND. A DEEP UPPER TROUGH AND ASSOCIATED SFC
LOW WILL LIFT NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE
OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LINEAR FEATURE ON RADAR LOOP RUNNING FROM KYNG TO KDUJ AT 11Z
APPEARS TO BE SFC TROUGH...WHICH IS PROGGED BY NR TERM MDLS TO
WASH OUT AS IT PRESSES SOUTH THIS MORNING. RIBBON OF HIGHER LOW
LVL MOISTURE ALONG AND IN ADVANCE OF THIS FEATURE HAS BEEN
SUPPORTING SPOTTY LGT SNOW/FZDZ ACROSS THE ALLEGHENY MTNS THIS
MORNING. WINT WX ADV...WHICH HAS BEEN IN EFFECT ACROSS THE N
MTNS...WILL EXPIRE AT 12Z AS FOCUS OF FREEZING PRECIP SHIFTS
SOUTH INTO THE LAUREL HIGHLANDS.

OROGRAPHIC FORCING OF SHALLOW LYR OF MOISTURE SHOULD CONTINUE TO
PRODUCE A BIT OF LGT SNOW OR FZDZ ACROSS CAMBRIA/SOMERSET
COUNTIES THRU ARND MIDDAY. HOWEVER...GIVEN THE VERY LGT NATURE OF
THE PRECIP AND THAT SOME IS FALLING AS SNOW...HAVE OPTED TO COVER
WITH AN SPS RATHER THAN A WSW. SFC OBS HAVE BEEN INDICATING BOTH
-SHSN AND -FZDZ AND MDL SOUNDINGS INDICATE BORDERLINE CLOUD TOP
TEMPS OF ARND -10C...SO WILL CONTINUE TO FCST SCT -SHSN AND PATCHY
-FZDZ OVR THE LAUREL HIGHLANDS THIS AM.

OTHERWISE...ARRIVAL OF DRIER AIR IN WAKE OF TROF SHOULD PRODUCE
PARTIAL CLEARING LATER TODAY...ESP WHERE WEST WIND DOWNSLOPES THE
MTNS ACROSS THE SUSQ VALLEY.

MAX TEMPS SHOULD BE SIMILAR TO THURSDAY...WITH U20S OVR THE
HIGHEST TERRAIN OF THE ALLEGHENIES...TO THE U30S ACROSS THE LOWER
SUSQ VALLEY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
HIGH PRESSURE AND ASSOC DRIER AIR MASS WILL BUILD IN FROM THE GRT
LKS TONIGHT...PROVIDING THE AREA WITH FAIR WX. FOR MUCH OF CENTRAL
PA...TONIGHT SHOULD FEATURE MCLEAR SKIES. HOWEVER...LOW LVL
MOISTURE TRAPPED BENEATH INVERSION MAY RESULT IN PERSISTENT
STRATOCU ACROSS THE LAUREL HIGHLANDS THIS EVENING.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS INTO THE REGION ON SATURDAY.
HOWEVER...ALL MDL DATA SUPPORTS A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS IN THE 30S.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE WILL SHIFT SLOWLY EASTWARD FROM THE GREAT LAKES
INTO NORTHERN NEW ENGLAND BY 12Z MONDAY. A MOISTURE-STARVED NRN
STREAM SHORTWAVE SHOULD PRODUCE A PERIOD OF CLOUDINESS SAT
NIGHT...BUT LIKELY NOT PRODUCE ANY PRECIP. LATEST MDL SOUNDINGS
POINT TOWARD A RELATIVELY BRIGHT SUNDAY IN THE WAKE OF THIS
FEATURE WITH NEAR SEASONAL TEMPS. SPLIT FLOW REGIME ACROSS THE
LOWER 48 WILL TRANSITION TO A HIGHLY AMPLIFIED PATTERN BY EARLY
NEXT WEEK ACROSS THE LOWER 48...WITH A DEEP NEGATIVELY TILTED
TROUGH EVOLVING OVER THE EASTERN 1/3RD OF THE CONUS.

THE MODELS SEEM TO BE FORMING A CONSENSUS ON THE PESKY LOW
THAT REFUSES TO BE WELL FORECAST...LIFTING IT SLOWLY FROM FL
PANHANDLE NNEWD JUST OFF THE EAST COAST SUN-MON ALONG A LOW LEVEL
BAROCLINIC ZONE THAT MAY NOT BUDGE PAST THE GULF STREAM AS THE
FLOW ALOFT TURNS SOUTHWESTERLY/PARALLEL TO THE COASTAL FRONT.
INCREASED POPS FOR MONDAY OVER THE SE BASED ON MULTI-MODEL/WPC
BLEND. COMPLEX SFC PATTERN WITH SOME HINTS AT LOW LEVEL CAD ALONG
WITH WAA ALOFT VIA SLY FLOW COULD MAKE FOR A MESSY MIXED PTYPE
TRANSITION.

AN INTENSE TRIPLE POINT SYSTEM DEVELOPING ON DEC 23-24 WILL
LIKELY STEAL THE HEADLINES GIVEN ITS TIMING AND LARGE PORTION OF
REAL ESTATE THAT WILL BE AFFECTED. WHILE THE DETAILS REMAIN
UNCLEAR AT THIS POINT...TEMPERATURES SHOULD BE WARM ENOUGH TO
SUPPORT RAIN ON THE FRONT SIDE OF THE SYSTEM BEFORE BRISK WNW
WINDS DRIVE STRONG CAA EAST OF THE APPALACHIANS. THE TIMING OF THE
COLD/OCCLUDED FRONT WILL BE KEY FOR PRECIPITATION TRANSITION FROM
RAIN TO SNOW SHOWERS. AS THE SYSTEM SPINS UP INTO EASTERN
CANADA...THE STRONG CAA CIRCULATING THROUGH THE GREAT LAKES AND OH
VLY SHOULD LEAD TO LAKE EFFECT/UPSLOPE/WRAP AROUND SNOW SHOWERS
OVER THE WESTERN ALLEGHENIES BY CHRISTMAS DAY. A PERIOD OF STRONG
GUSTY WINDS ARE HIGHLY PROBABLE AS THE DYNAMIC SYSTEM INTENSIFIES
SHIFTING NWWD FROM NEW ENGLAND INTO ONTARIO/QUEBEC.

THE TAKE HOME MESSAGE IS THAT A VOLATILE PERIOD OF WEATHER WILL
IMPACT THE AREA THROUGH CHRISTMAS DAY WITH POTENTIAL WIND...RAIN
AND SNOW IMPACTS ALL ON THE TABLE. STAY TUNED.

&&

.AVIATION /11Z FRIDAY THROUGH TUESDAY/...
LOW LVL MOISTURE TRAPPED BENEATH INVERSION AND NORTHWEST FLOW
OVER THE EASTERN GLAKS WILL KEEP STRATO CU IN PLACE ACROSS MOST
OF CENTRAL PA THROUGH THE OVERNIGHT. LATEST MDL SOUNDINGS POINT
TOWARD PREDOMINANTLY IFR CIGS/VSBYS AT KBFD AND KJST. THE MODELS
SHOW SOME VARIATION BUT MVFR CIGS AT ALL OTHER TAF SITES EITHER
ARE CURRENTLY OCCURRING OR WILL OCCUR BETWEEN 06Z TO 12Z.

A TROUGH OF LOW PRESSURE WILL PUSH THRU THE REGION OVERNIGHT...
PERHAPS PRODUCING A PERIOD OF STEADIER LGT SNOW AT KBFD AND KJST
BTWN 06Z-12Z FRIDAY WITH VSBYS IN THE 2 TO 4SM RANGE. SKIES WILL
STEADILY IMPROVE AS THE DAY CONTINUES WITH VFR CIGS BY 15Z AT ALL
TAF SITES. EXPECT REDUCING CONDITIONS FRI EVENING AT ONLY BFD AND
POSSIBLY JST.


OUTLOOK...

FRI...EARLY AM -SHSN/REDUCED VSBYS POSS AT KJST.

SAT-SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE.

TUE...LOW CIGS WITH RAIN LIKELY.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR
PAZ004>006-010-011-037.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/STEINBUGL
AVIATION...CERU/RXR



000
FXUS61 KCTP 191130
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
630 AM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE OVER THE GREAT LAKES WILL SLIDE EAST INTO
PENNSYLVANIA THIS WEEKEND. A DEEP UPPER TROUGH AND ASSOCIATED SFC
LOW WILL LIFT NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE
OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LINEAR FEATURE ON RADAR LOOP RUNNING FROM KYNG TO KDUJ AT 11Z
APPEARS TO BE SFC TROUGH...WHICH IS PROGGED BY NR TERM MDLS TO
WASH OUT AS IT PRESSES SOUTH THIS MORNING. RIBBON OF HIGHER LOW
LVL MOISTURE ALONG AND IN ADVANCE OF THIS FEATURE HAS BEEN
SUPPORTING SPOTTY LGT SNOW/FZDZ ACROSS THE ALLEGHENY MTNS THIS
MORNING. WINT WX ADV...WHICH HAS BEEN IN EFFECT ACROSS THE N
MTNS...WILL EXPIRE AT 12Z AS FOCUS OF FREEZING PRECIP SHIFTS
SOUTH INTO THE LAUREL HIGHLANDS.

OROGRAPHIC FORCING OF SHALLOW LYR OF MOISTURE SHOULD CONTINUE TO
PRODUCE A BIT OF LGT SNOW OR FZDZ ACROSS CAMBRIA/SOMERSET
COUNTIES THRU ARND MIDDAY. HOWEVER...GIVEN THE VERY LGT NATURE OF
THE PRECIP AND THAT SOME IS FALLING AS SNOW...HAVE OPTED TO COVER
WITH AN SPS RATHER THAN A WSW. SFC OBS HAVE BEEN INDICATING BOTH
-SHSN AND -FZDZ AND MDL SOUNDINGS INDICATE BORDERLINE CLOUD TOP
TEMPS OF ARND -10C...SO WILL CONTINUE TO FCST SCT -SHSN AND PATCHY
-FZDZ OVR THE LAUREL HIGHLANDS THIS AM.

OTHERWISE...ARRIVAL OF DRIER AIR IN WAKE OF TROF SHOULD PRODUCE
PARTIAL CLEARING LATER TODAY...ESP WHERE WEST WIND DOWNSLOPES THE
MTNS ACROSS THE SUSQ VALLEY.

MAX TEMPS SHOULD BE SIMILAR TO THURSDAY...WITH U20S OVR THE
HIGHEST TERRAIN OF THE ALLEGHENIES...TO THE U30S ACROSS THE LOWER
SUSQ VALLEY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
HIGH PRESSURE AND ASSOC DRIER AIR MASS WILL BUILD IN FROM THE GRT
LKS TONIGHT...PROVIDING THE AREA WITH FAIR WX. FOR MUCH OF CENTRAL
PA...TONIGHT SHOULD FEATURE MCLEAR SKIES. HOWEVER...LOW LVL
MOISTURE TRAPPED BENEATH INVERSION MAY RESULT IN PERSISTENT
STRATOCU ACROSS THE LAUREL HIGHLANDS THIS EVENING.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS INTO THE REGION ON SATURDAY.
HOWEVER...ALL MDL DATA SUPPORTS A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS IN THE 30S.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE WILL SHIFT SLOWLY EASTWARD FROM THE GREAT LAKES
INTO NORTHERN NEW ENGLAND BY 12Z MONDAY. A MOISTURE-STARVED NRN
STREAM SHORTWAVE SHOULD PRODUCE A PERIOD OF CLOUDINESS SAT
NIGHT...BUT LIKELY NOT PRODUCE ANY PRECIP. LATEST MDL SOUNDINGS
POINT TOWARD A RELATIVELY BRIGHT SUNDAY IN THE WAKE OF THIS
FEATURE WITH NEAR SEASONAL TEMPS. SPLIT FLOW REGIME ACROSS THE
LOWER 48 WILL TRANSITION TO A HIGHLY AMPLIFIED PATTERN BY EARLY
NEXT WEEK ACROSS THE LOWER 48...WITH A DEEP NEGATIVELY TILTED
TROUGH EVOLVING OVER THE EASTERN 1/3RD OF THE CONUS.

THE MODELS SEEM TO BE FORMING A CONSENSUS ON THE PESKY LOW
THAT REFUSES TO BE WELL FORECAST...LIFTING IT SLOWLY FROM FL
PANHANDLE NNEWD JUST OFF THE EAST COAST SUN-MON ALONG A LOW LEVEL
BAROCLINIC ZONE THAT MAY NOT BUDGE PAST THE GULF STREAM AS THE
FLOW ALOFT TURNS SOUTHWESTERLY/PARALLEL TO THE COASTAL FRONT.
INCREASED POPS FOR MONDAY OVER THE SE BASED ON MULTI-MODEL/WPC
BLEND. COMPLEX SFC PATTERN WITH SOME HINTS AT LOW LEVEL CAD ALONG
WITH WAA ALOFT VIA SLY FLOW COULD MAKE FOR A MESSY MIXED PTYPE
TRANSITION.

AN INTENSE TRIPLE POINT SYSTEM DEVELOPING ON DEC 23-24 WILL
LIKELY STEAL THE HEADLINES GIVEN ITS TIMING AND LARGE PORTION OF
REAL ESTATE THAT WILL BE AFFECTED. WHILE THE DETAILS REMAIN
UNCLEAR AT THIS POINT...TEMPERATURES SHOULD BE WARM ENOUGH TO
SUPPORT RAIN ON THE FRONT SIDE OF THE SYSTEM BEFORE BRISK WNW
WINDS DRIVE STRONG CAA EAST OF THE APPALACHIANS. THE TIMING OF THE
COLD/OCCLUDED FRONT WILL BE KEY FOR PRECIPITATION TRANSITION FROM
RAIN TO SNOW SHOWERS. AS THE SYSTEM SPINS UP INTO EASTERN
CANADA...THE STRONG CAA CIRCULATING THROUGH THE GREAT LAKES AND OH
VLY SHOULD LEAD TO LAKE EFFECT/UPSLOPE/WRAP AROUND SNOW SHOWERS
OVER THE WESTERN ALLEGHENIES BY CHRISTMAS DAY. A PERIOD OF STRONG
GUSTY WINDS ARE HIGHLY PROBABLE AS THE DYNAMIC SYSTEM INTENSIFIES
SHIFTING NWWD FROM NEW ENGLAND INTO ONTARIO/QUEBEC.

THE TAKE HOME MESSAGE IS THAT A VOLATILE PERIOD OF WEATHER WILL
IMPACT THE AREA THROUGH CHRISTMAS DAY WITH POTENTIAL WIND...RAIN
AND SNOW IMPACTS ALL ON THE TABLE. STAY TUNED.

&&

.AVIATION /11Z FRIDAY THROUGH TUESDAY/...
LOW LVL MOISTURE TRAPPED BENEATH INVERSION AND NORTHWEST FLOW
OVER THE EASTERN GLAKS WILL KEEP STRATO CU IN PLACE ACROSS MOST
OF CENTRAL PA THROUGH THE OVERNIGHT. LATEST MDL SOUNDINGS POINT
TOWARD PREDOMINANTLY IFR CIGS/VSBYS AT KBFD AND KJST. THE MODELS
SHOW SOME VARIATION BUT MVFR CIGS AT ALL OTHER TAF SITES EITHER
ARE CURRENTLY OCCURRING OR WILL OCCUR BETWEEN 06Z TO 12Z.

A TROUGH OF LOW PRESSURE WILL PUSH THRU THE REGION OVERNIGHT...
PERHAPS PRODUCING A PERIOD OF STEADIER LGT SNOW AT KBFD AND KJST
BTWN 06Z-12Z FRIDAY WITH VSBYS IN THE 2 TO 4SM RANGE. SKIES WILL
STEADILY IMPROVE AS THE DAY CONTINUES WITH VFR CIGS BY 15Z AT ALL
TAF SITES. EXPECT REDUCING CONDITIONS FRI EVENING AT ONLY BFD AND
POSSIBLY JST.


OUTLOOK...

FRI...EARLY AM -SHSN/REDUCED VSBYS POSS AT KJST.

SAT-SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE.

TUE...LOW CIGS WITH RAIN LIKELY.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR
PAZ004>006-010-011-037.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/STEINBUGL
AVIATION...CERU/RXR




000
FXUS61 KPBZ 191050
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
550 AM EST FRI DEC 19 2014

.SYNOPSIS...
BUILDING HIGH PRESSURE IS EXPECTED THROUGH THE WEEKEND...THOUGH
CLOUDS WILL REMAIN.

&&

.NEAR TERM /THROUGH TONIGHT/...
MOISTURE TRAPPED UNDER THE INVERSION NEAR H85 CONTINUES TO FALL OUT
AS FREEZING DRIZZLE MIXING AT TIMES WITH LIGHT SNOW. BEGINNING TO
SEE SOME REPORTS IN THE PITTSBURGH METRO AREA...AND FURTHER SOUTH
AND WEST INTO ERN OHIO. HAVE EXPANDED THE WINTER WEATHER ADVISORY TO
INCLUDE THIS AREA. THE BULK OF THIS ACTIVITY REMAINS JUST WEST OF
THE CWA BOUNDARY WHERE MOISTURE AVAILABILITY IS A LITTLE BETTER DUE
TO THE PROXIMITY TO LAKE ERIE.

RECENT RADAR TRENDS SHOW A LAKE-ENHANCED BAND NEAR CLE DISLODGE ITSELF
FROM THE SRN SHORELINE OF LAKE ERIE. THIS IS IN RESPONSE TO THE
WINDS VEERING TO NEARLY NORTHERLY AS THE LLVL SW TROF AXIS SWINGS
SOUTHWARD. WHILE THE INDIVIDUAL BAND IS NOT EXPECTED TO IMPACT OUR
AREA DIRECTLY...IT CAN BE USED AS A GOOD PROXY FOR WHERE THE
DOWNSTREAM MOISTURE IS ENTERING OUR FORECAST AREA. AS THIS BAND
CONTINUES TO PIVOT SOUTHWARD...EXPECT TO SEE LIGHT SNOW AND FREEZING
DRIZZLE REPORTS IN OUR AREA TO FOLLOW SUIT.

THE HI-RES MODELS DID A GREAT JOB HANDLING THE LLVL MOISTURE AND
PROGRESSION OF THE TROF...KEYING IN ON THE ATTENDANT MID-LEVEL
DEFORMATION ZONE TO GENERATE SHOWER ACTIVITY. AS IT CONTINUES IT
TREK SOUTH OF LAKE ERIE...THE MOISTURE BEGINS TO ERODE ALONG WITH
THE DEFORMATION ZONE GETTING WASHED OUT. WITH STILL ABUNDANT LLVL
MOISTURE AVAILABLE...WOULD EXPECT REPORTS OF DZ TO CONTINUE THROUGH
SUNRISE...BUT NOT MUCH BEYOND THAT. HAVE EXTENDED THE ADVISORY
THROUGH 9AM.

CLOUDS WILL CONTINUE TO PLAGUE THE CWA FOR YET ANOTHER DAY KEEPING
DAYTIME HIGHS IN CHECK. INCREASING SUBSIDENCE UNDER HIGH PRESSURE
WILL GRADUALLY LOWER INVERSION HEIGHTS THROUGH THE DAY FRIDAY
SQUASHING REMAINING PRECIPITATION CHANCES.
TAX

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
HIGH PRESSURE WILL REIGN OVER THE FORECAST AREA THROUGH THE
WEEKEND. A WEAK OPEN WAVE TRIES TO SKIRT THE SRN EXTENT OF THE SFC
HIGH SAT AFTERNOON...BUT MODELS CONTINUE TO TREND IT FURTHER SOUTH
WELL OUT OF OUR REGION. AFTER LARGELY ZONAL FLOW ALOFT THROUGH
SUNDAY THE UPPER LEVEL PATTERN FAVORS SWRLY FLOW ON THE BACKSIDE
OF THE SFC HIGH. THIS WILL WORK TO DRIVE WARMER TEMPS INTO THE
FORECAST AREA WITH HIGHS DRIVING ABOVE AVERAGE HEADING INTO EARLY
NEXT WEEK.
TAX

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
WHILE THE MODELS AGREE ON A DEEPENING UPPER LEVEL TROUGH TO CLOSE
OFF OVER THE GREAT LAKES THROUGH THE PERIOD THE DETAILS OF HOW
THIS EXACTLY UNFOLDS WILL BE CRITICAL. BY MONDAY SOUTHERN STREAM
SHORTWAVE AHEAD OF MAIN NORTHERN STREAM UPPER TROUGH DIGGING INTO
THE NORTHERN PLAINS WILL PRODUCE LOW PRESSURE ACROSS THE CAROLINAS
MOVING OFF SHORE OF THE EAST COAST. THE SOUTHEAST RIDGES MAY BE
BRUSHED BY LIGHT RAIN FROM THIS SYSTEM. NEXT UP IS DEEPENING LOW
PRESSURE OVER THE OHIO VALLEY AHEAD OF SHARPLY DIGGING UPPER
TROUGH AND CLOSED LOW MOVING INTO THE WESTERN GREAT LAKES. UPPER
OHIO VALLEY LOOKS TO BE ON THE WARM SIDE OF THE SYSTEM TUESDAY
INTO WEDNESDAY WITH RAIN...FOLLOWED BY STRONG COLD FRONT AND COLD
ADVECTION LATER WEDNESDAY NIGHT AND THURSDAY WITH SNOW SHOWERS.
WITH SUCH A STRONG SYSTEM ALOFT AND FAST DEEPENING LOW PRESSURE AT
THE SURFACE TIMING OF COLD AIR AND EXACT TRACK WILL LIKELY CHANGE
AS WE GET CLOSER TO CHRISTMAS. ALL IN ALL PREVIOUS FORECAST IS
LITTLE CHANGED WITH ONLY MINOR ADJUSTMENTS BASED ON NEWEST WPC
EXTENDED PROGS.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
UPDATED TAFS TO INCLUDE MENTION OF FREEZING DRIZZLE FOR SITES
NORTH OF INTERSTATE 70 THROUGH EARLY THIS MORNING BASED ON LATEST
OBS AND LATEST HI RES AND RAPID REFRESH GUIDANCE SHOWING
INDICATING MOISTURE IN THE COLUMN LIMITED TO LOWER LEVELS NOT COLD
ENOUGH FOR ICE CRYSTAL FORMATION...THUS...FINE MIST AND LIGHT
DRIZZLE EXPECTED THROUGH 9AM WILL REMAIN LIQUID AND FREEZE ON
CONTACT. DO NOT EXPECT ANY PERIODS OF RAPID ICE DEVELOPMENT BUT
WILL LIKELY FOR A LIGHT GLAZE OVER THE NEXT SEVERAL HOURS.
ICE POTENTIAL WILL LIKELY BE OVER BY MID MORNING AS MOISTURE POOL
BECOMES TOO SHALLOW...WITH CIG RESTRICTIONS LARGELY MVFR THROUGH
MUCH OF THE DAY...IMPROVING TO VFR STARTING LATE THIS AFTERNOON.


OUTLOOK.../FRIDAY NIGHT THROUGH TUESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR
     OHZ039>041-048>050.
PA...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR
     PAZ007>009-013>016-020>022.
WV...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR WVZ001.

&&

$$






000
FXUS61 KCTP 190931
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
431 AM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE OVER THE GREAT LAKES WILL SLIDE EAST INTO
PENNSYLVANIA THIS WEEKEND. A DEEP UPPER TROUGH AND ASSOCIATED SFC
LOW WILL LIFT NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE
OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MAIN FCST ISSUE THIS MORNING WILL BE THE LIKELIHOOD OF VERY LGT
WINTRY PRECIP OVR THE W MTNS...THE RESULT OF OROGRAPHIC FORCING
AND SHALLOW LYR OF MOISTURE. HI-RES MDL DATA SHOWS A PLUME OF
HIGHER LOW LVL MOISTURE IN ASSOC WITH SFC TROUGH MOVING INTO THE
NW MTNS EARLY THIS AM. THIS BOUNDARY IS EVIDENT AS A THIN LINE OF
HIGHER RADAR RETURNS RUNNING FROM CLE INTO NW PA AT 09Z. SFC OBS
INDICATE PTYPES OF BOTH -SHSN AND -FZDZ IN THE REGION AND MDL
SOUNDINGS INDICATE BORDERLINE CLOUD TOP TEMPS OF ARND -10C...SO
WILL CONTINUE TO FCST SCT -SHSN AND PATCHY -FZDZ OVR THE W MTNS
THIS AM. ADVISORY WAS COLLABORATED WITH ADJ OFFICES OVR THE N
MTNS...WHERE MDLS INDICATE A GREATER LIKELIHOOD OF MEASURABLE
FZDZ. HOWEVER...SOME FZDZ IS ALSO LIKELY FURTHER SOUTH OVR THE
LAUREL HIGHLANDS. 09Z OBSERVATION AT KJST INDICATED NO MEASURABLE
PRECIP BUT 0.01 ICE ACCRETION FROM FREEZING FOG.

SFC TROUGH AND RIBBON OF HIGHER LOW LVL MOISTURE WILL SLIDE SOUTH
ACROSS THE REGION LATER TODAY. OROGRAPHIC LIFTING OF THIS SHALLOW
MOIST LYR MAY CONTINUE TO PRODUCE A BIT OF -SHSN/-FZDZ ACROSS THE
LAUREL HIGHLANDS THRU EARLY AFTN. OTHERWISE...ARRIVAL OF DRIER
AIR IN WAKE OF TROF SHOULD PRODUCE PARTIAL CLEARING LATER TODAY...ESP
WHERE WEST WIND DOWNSLOPES THE MTNS ACROSS THE SUSQ VALLEY.

MAX TEMPS SHOULD BE SIMILAR TO THURSDAY...WITH U20S OVR THE
HIGHEST TERRAIN OF THE ALLEGHENIES...TO THE U30S ACROSS THE LOWER
SUSQ VALLEY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
HIGH PRESSURE AND ASSOC DRIER AIR MASS WILL BUILD IN FROM THE GRT
LKS TONIGHT...PROVIDING THE AREA WITH FAIR WX. FOR MUCH OF CENTRAL
PA...TONIGHT SHOULD FEATURE MCLEAR SKIES. HOWEVER...LOW LVL
MOISTURE TRAPPED BENEATH INVERSION MAY RESULT IN PERSISTENT
STRATOCU ACROSS THE LAUREL HIGHLANDS THIS EVENING.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS INTO THE REGION ON SATURDAY.
HOWEVER...ALL MDL DATA SUPPORTS A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS IN THE 30S.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE WILL SHIFT SLOWLY EASTWARD FROM THE GREAT LAKES
INTO NORTHERN NEW ENGLAND BY 12Z MONDAY. A MOISTURE-STARVED NRN
STREAM SHORTWAVE SHOULD PRODUCE A PERIOD OF CLOUDINESS SAT
NIGHT...BUT LIKELY NOT PRODUCE ANY PRECIP. LATEST MDL SOUNDINGS
POINT TOWARD A RELATIVELY BRIGHT SUNDAY IN THE WAKE OF THIS
FEATURE WITH NEAR SEASONAL TEMPS. SPLIT FLOW REGIME ACROSS THE
LOWER 48 WILL TRANSITION TO A HIGHLY AMPLIFIED PATTERN BY EARLY
NEXT WEEK ACROSS THE LOWER 48...WITH A DEEP NEGATIVELY TILTED
TROUGH EVOLVING OVER THE EASTERN 1/3RD OF THE CONUS.

THE MODELS SEEM TO BE FORMING A CONSENSUS ON THE PESKY LOW
THAT REFUSES TO BE WELL FORECAST...LIFTING IT SLOWLY FROM FL
PANHANDLE NNEWD JUST OFF THE EAST COAST SUN-MON ALONG A LOW LEVEL
BAROCLINIC ZONE THAT MAY NOT BUDGE PAST THE GULF STREAM AS THE
FLOW ALOFT TURNS SOUTHWESTERLY/PARALLEL TO THE COASTAL FRONT.
INCREASED POPS FOR MONDAY OVER THE SE BASED ON MULTI-MODEL/WPC
BLEND. COMPLEX SFC PATTERN WITH SOME HINTS AT LOW LEVEL CAD ALONG
WITH WAA ALOFT VIA SLY FLOW COULD MAKE FOR A MESSY MIXED PTYPE
TRANSITION.

AN INTENSE TRIPLE POINT SYSTEM DEVELOPING ON DEC 23-24 WILL
LIKELY STEAL THE HEADLINES GIVEN ITS TIMING AND LARGE PORTION OF
REAL ESTATE THAT WILL BE AFFECTED. WHILE THE DETAILS REMAIN
UNCLEAR AT THIS POINT...TEMPERATURES SHOULD BE WARM ENOUGH TO
SUPPORT RAIN ON THE FRONT SIDE OF THE SYSTEM BEFORE BRISK WNW
WINDS DRIVE STRONG CAA EAST OF THE APPALACHIANS. THE TIMING OF THE
COLD/OCCLUDED FRONT WILL BE KEY FOR PRECIPITATION TRANSITION FROM
RAIN TO SNOW SHOWERS. AS THE SYSTEM SPINS UP INTO EASTERN
CANADA...THE STRONG CAA CIRCULATING THROUGH THE GREAT LAKES AND OH
VLY SHOULD LEAD TO LAKE EFFECT/UPSLOPE/WRAP AROUND SNOW SHOWERS
OVER THE WESTERN ALLEGHENIES BY CHRISTMAS DAY. A PERIOD OF STRONG
GUSTY WINDS ARE HIGHLY PROBABLE AS THE DYNAMIC SYSTEM INTENSIFIES
SHIFTING NWWD FROM NEW ENGLAND INTO ONTARIO/QUEBEC.

THE TAKE HOME MESSAGE IS THAT A VOLATILE PERIOD OF WEATHER WILL
IMPACT THE AREA THROUGH CHRISTMAS DAY WITH POTENTIAL WIND...RAIN
AND SNOW IMPACTS ALL ON THE TABLE. STAY TUNED.

&&

.AVIATION /09Z FRIDAY THROUGH TUESDAY/...
LOW LVL MOISTURE TRAPPED BENEATH INVERSION AND NORTHWEST FLOW
OVER THE EASTERN GLAKS WILL KEEP STRATO CU IN PLACE ACROSS MOST
OF CENTRAL PA THROUGH THE OVERNIGHT. LATEST MDL SOUNDINGS POINT
TOWARD PREDOMINANTLY IFR CIGS/VSBYS AT KBFD AND KJST. THE MODELS
SHOW SOME VARIATION BUT MVFR CIGS AT ALL OTHER TAF SITES EITHER
ARE CURRENTLY OCCURRING OR WILL OCCUR BETWEEN 06Z TO 12Z.

A TROUGH OF LOW PRESSURE WILL PUSH THRU THE REGION OVERNIGHT...
PERHAPS PRODUCING A PERIOD OF STEADIER LGT SNOW AT KBFD AND KJST
BTWN 06Z-12Z FRIDAY WITH VSBYS IN THE 2 TO 4SM RANGE. SKIES WILL
STEADILY IMPROVE AS THE DAY CONTINUES WITH VFR CIGS BY 15Z AT ALL
TAF SITES. EXPECT REDUCING CONDITIONS FRI EVENING AT ONLY BFD AND
POSSIBLY JST.


OUTLOOK...

FRI...EARLY AM -SHSN/REDUCED VSBYS POSS AT KJST.

SAT-SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE.

TUE...LOW CIGS WITH RAIN LIKELY.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR
PAZ004>006-010-011-037.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/STEINBUGL
AVIATION...CERU/RXR




000
FXUS61 KCTP 190931
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
431 AM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE OVER THE GREAT LAKES WILL SLIDE EAST INTO
PENNSYLVANIA THIS WEEKEND. A DEEP UPPER TROUGH AND ASSOCIATED SFC
LOW WILL LIFT NORTHEAST THROUGH THE GREAT LAKES DURING THE MIDDLE
OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MAIN FCST ISSUE THIS MORNING WILL BE THE LIKELIHOOD OF VERY LGT
WINTRY PRECIP OVR THE W MTNS...THE RESULT OF OROGRAPHIC FORCING
AND SHALLOW LYR OF MOISTURE. HI-RES MDL DATA SHOWS A PLUME OF
HIGHER LOW LVL MOISTURE IN ASSOC WITH SFC TROUGH MOVING INTO THE
NW MTNS EARLY THIS AM. THIS BOUNDARY IS EVIDENT AS A THIN LINE OF
HIGHER RADAR RETURNS RUNNING FROM CLE INTO NW PA AT 09Z. SFC OBS
INDICATE PTYPES OF BOTH -SHSN AND -FZDZ IN THE REGION AND MDL
SOUNDINGS INDICATE BORDERLINE CLOUD TOP TEMPS OF ARND -10C...SO
WILL CONTINUE TO FCST SCT -SHSN AND PATCHY -FZDZ OVR THE W MTNS
THIS AM. ADVISORY WAS COLLABORATED WITH ADJ OFFICES OVR THE N
MTNS...WHERE MDLS INDICATE A GREATER LIKELIHOOD OF MEASURABLE
FZDZ. HOWEVER...SOME FZDZ IS ALSO LIKELY FURTHER SOUTH OVR THE
LAUREL HIGHLANDS. 09Z OBSERVATION AT KJST INDICATED NO MEASURABLE
PRECIP BUT 0.01 ICE ACCRETION FROM FREEZING FOG.

SFC TROUGH AND RIBBON OF HIGHER LOW LVL MOISTURE WILL SLIDE SOUTH
ACROSS THE REGION LATER TODAY. OROGRAPHIC LIFTING OF THIS SHALLOW
MOIST LYR MAY CONTINUE TO PRODUCE A BIT OF -SHSN/-FZDZ ACROSS THE
LAUREL HIGHLANDS THRU EARLY AFTN. OTHERWISE...ARRIVAL OF DRIER
AIR IN WAKE OF TROF SHOULD PRODUCE PARTIAL CLEARING LATER TODAY...ESP
WHERE WEST WIND DOWNSLOPES THE MTNS ACROSS THE SUSQ VALLEY.

MAX TEMPS SHOULD BE SIMILAR TO THURSDAY...WITH U20S OVR THE
HIGHEST TERRAIN OF THE ALLEGHENIES...TO THE U30S ACROSS THE LOWER
SUSQ VALLEY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
HIGH PRESSURE AND ASSOC DRIER AIR MASS WILL BUILD IN FROM THE GRT
LKS TONIGHT...PROVIDING THE AREA WITH FAIR WX. FOR MUCH OF CENTRAL
PA...TONIGHT SHOULD FEATURE MCLEAR SKIES. HOWEVER...LOW LVL
MOISTURE TRAPPED BENEATH INVERSION MAY RESULT IN PERSISTENT
STRATOCU ACROSS THE LAUREL HIGHLANDS THIS EVENING.

WAA ALOFT IN ADVANCE OF SHORTWAVE LIFTING OUT OF THE MISS VALLEY
WILL LIKELY SPREAD SOME THIN CIRRUS INTO THE REGION ON SATURDAY.
HOWEVER...ALL MDL DATA SUPPORTS A DRY DAY WITH SFC RIDGE AND LOW
PWAT AIRMASS OVR THE STATE. MAX TEMPS SHOULD BE FAIRLY CLOSE TO
SEASONAL NORMS IN THE 30S.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE WILL SHIFT SLOWLY EASTWARD FROM THE GREAT LAKES
INTO NORTHERN NEW ENGLAND BY 12Z MONDAY. A MOISTURE-STARVED NRN
STREAM SHORTWAVE SHOULD PRODUCE A PERIOD OF CLOUDINESS SAT
NIGHT...BUT LIKELY NOT PRODUCE ANY PRECIP. LATEST MDL SOUNDINGS
POINT TOWARD A RELATIVELY BRIGHT SUNDAY IN THE WAKE OF THIS
FEATURE WITH NEAR SEASONAL TEMPS. SPLIT FLOW REGIME ACROSS THE
LOWER 48 WILL TRANSITION TO A HIGHLY AMPLIFIED PATTERN BY EARLY
NEXT WEEK ACROSS THE LOWER 48...WITH A DEEP NEGATIVELY TILTED
TROUGH EVOLVING OVER THE EASTERN 1/3RD OF THE CONUS.

THE MODELS SEEM TO BE FORMING A CONSENSUS ON THE PESKY LOW
THAT REFUSES TO BE WELL FORECAST...LIFTING IT SLOWLY FROM FL
PANHANDLE NNEWD JUST OFF THE EAST COAST SUN-MON ALONG A LOW LEVEL
BAROCLINIC ZONE THAT MAY NOT BUDGE PAST THE GULF STREAM AS THE
FLOW ALOFT TURNS SOUTHWESTERLY/PARALLEL TO THE COASTAL FRONT.
INCREASED POPS FOR MONDAY OVER THE SE BASED ON MULTI-MODEL/WPC
BLEND. COMPLEX SFC PATTERN WITH SOME HINTS AT LOW LEVEL CAD ALONG
WITH WAA ALOFT VIA SLY FLOW COULD MAKE FOR A MESSY MIXED PTYPE
TRANSITION.

AN INTENSE TRIPLE POINT SYSTEM DEVELOPING ON DEC 23-24 WILL
LIKELY STEAL THE HEADLINES GIVEN ITS TIMING AND LARGE PORTION OF
REAL ESTATE THAT WILL BE AFFECTED. WHILE THE DETAILS REMAIN
UNCLEAR AT THIS POINT...TEMPERATURES SHOULD BE WARM ENOUGH TO
SUPPORT RAIN ON THE FRONT SIDE OF THE SYSTEM BEFORE BRISK WNW
WINDS DRIVE STRONG CAA EAST OF THE APPALACHIANS. THE TIMING OF THE
COLD/OCCLUDED FRONT WILL BE KEY FOR PRECIPITATION TRANSITION FROM
RAIN TO SNOW SHOWERS. AS THE SYSTEM SPINS UP INTO EASTERN
CANADA...THE STRONG CAA CIRCULATING THROUGH THE GREAT LAKES AND OH
VLY SHOULD LEAD TO LAKE EFFECT/UPSLOPE/WRAP AROUND SNOW SHOWERS
OVER THE WESTERN ALLEGHENIES BY CHRISTMAS DAY. A PERIOD OF STRONG
GUSTY WINDS ARE HIGHLY PROBABLE AS THE DYNAMIC SYSTEM INTENSIFIES
SHIFTING NWWD FROM NEW ENGLAND INTO ONTARIO/QUEBEC.

THE TAKE HOME MESSAGE IS THAT A VOLATILE PERIOD OF WEATHER WILL
IMPACT THE AREA THROUGH CHRISTMAS DAY WITH POTENTIAL WIND...RAIN
AND SNOW IMPACTS ALL ON THE TABLE. STAY TUNED.

&&

.AVIATION /09Z FRIDAY THROUGH TUESDAY/...
LOW LVL MOISTURE TRAPPED BENEATH INVERSION AND NORTHWEST FLOW
OVER THE EASTERN GLAKS WILL KEEP STRATO CU IN PLACE ACROSS MOST
OF CENTRAL PA THROUGH THE OVERNIGHT. LATEST MDL SOUNDINGS POINT
TOWARD PREDOMINANTLY IFR CIGS/VSBYS AT KBFD AND KJST. THE MODELS
SHOW SOME VARIATION BUT MVFR CIGS AT ALL OTHER TAF SITES EITHER
ARE CURRENTLY OCCURRING OR WILL OCCUR BETWEEN 06Z TO 12Z.

A TROUGH OF LOW PRESSURE WILL PUSH THRU THE REGION OVERNIGHT...
PERHAPS PRODUCING A PERIOD OF STEADIER LGT SNOW AT KBFD AND KJST
BTWN 06Z-12Z FRIDAY WITH VSBYS IN THE 2 TO 4SM RANGE. SKIES WILL
STEADILY IMPROVE AS THE DAY CONTINUES WITH VFR CIGS BY 15Z AT ALL
TAF SITES. EXPECT REDUCING CONDITIONS FRI EVENING AT ONLY BFD AND
POSSIBLY JST.


OUTLOOK...

FRI...EARLY AM -SHSN/REDUCED VSBYS POSS AT KJST.

SAT-SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE.

TUE...LOW CIGS WITH RAIN LIKELY.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR
PAZ004>006-010-011-037.

&&

$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD/STEINBUGL
AVIATION...CERU/RXR



000
FXUS61 KPHI 190924
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
424 AM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE OVER THE NORTHERN GREAT LAKES WILL MOVE INTO THE OHIO
VALLEY THIS MORNING. LOW PRESSURE IS EXPECTED TO FORM OVER THE GULF
STATES LATE TONIGHT AND TRACK ACROSS GEORGIA SATURDAY. A STRONG LOW
PRESSURE SYSTEM AND COLD FRONT MAY MOVE THROUGH THE EASTERN SEABOARD ON
CHRISTMAS EVE.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SURFACE HIGH CONTINUES TO SLIDE CLOSER TO THE REGION TODAY. HOWEVER,
LIKE LAST WEEK, THERE APPEARS TO BE ABUNDANT MOISTURE BELOW THE
INVERSION, SO DESPITE THE SYNOPTIC SCALE SUBSIDENCE, SHOULD STILL
SEE QUITE A BIT OF CLOUD COVER. WITH LITTLE CHANGE IN THE AIR MASS,
EXPECT HIGHS NEAR MAX TEMPS YESTERDAY WHICH ARE NEAR OR JUST BELOW
NORMALS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
THE BIGGEST CHANGE TONIGHT FROM THE LAST FEW NIGHTS IS THAT WITH THE
HIGH INCHING CLOSER AND THUS THE PRESSURE GRADIENT ACROSS THE REGION
DECREASING, WINDS SHOULD BE LIGHT. THOUGH WE WOULD TYPICALLY EXPECT
TO SEE CLEARING SKIES IN THIS PATTERN, WITH THE LOW LEVEL MOISTURE
LIKELY STILL IN PLACE, COULD STILL SEE QUITE A BIT OF CLOUD COVER,
ESPECIALLY OVER THE NORTHERN HALF OF THE REGION.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
MID-LEVEL FLOW THE NEXT COUPLE OF DAYS IS RATHER FLAT THOUGH A
CHANGE TO THAT PATTERN APPEARS LIKELY BY THE END OF THE WEEKEND. A
DEEP TROUGH EMERGES ACROSS THE CENTRAL U.S. BY TUESDAY AS MULTIPLE
PACIFIC NORTHWEST WAVES ROUND THE BASE OF THE TROUGH AND ACROSS OUR
REGION...WE ARE HEADING FOR A VERY UNSETTLED PERIOD BY EARLY NEXT
WEEK.

SATURDAY - SUNDAY...LOOKS MOSTLY DRY BOTH DAYS WITH HIGH PRESSURE
ANCHORED TO OUR NORTHEAST. THERE IS SOME NORTHERN STREAM ENERGY TO
CONTEND WITH LATE SATURDAY NIGHT WITH THE HELP OF A WEAK INVERTED
TROUGH OFFSHORE. THIS COMBINATION COULD TOUCH OFF A FEW SHOWERS AS
ALONG THE NORTHEASTERN NEW JERSEY COAST BUT WILL BE OF LITTLE
CONSEQUENCE. ONSHORE FLOW WILL HELP TO KEEP AMPLE LOW-LEVEL MOISTURE
STREAMING INTO THE REGION, UNDER THE SUBSIDENCE INVERSION. SATURDAY
COULD BE THE SUNNIER DAY THAN SUNDAY, BUT EACH DAY THE CONVECTIVE
TEMPERATURES LOOK TO BE REACHED SO IT MAY BE SHORT LIVED.

MONDAY - TUESDAY...ONCE THE AFOREMENTIONED SYSTEM ABOVE DEPARTS
ANOTHER, BETTER DEFINED SYSTEM MOVES OFF THE CAROLINA COAST AND OUT
TO SEA ON TUESDAY. WEAK BAROCLINIC ZONE OFF THE MID-ATLANTIC COAST
WILL ALLOW FOR AMPLE MOISTURE TO ADVECT IN FROM THE SOUTH. AS THE
WAVE OF LOW PRESSURE MOVES BY IT WILL TAP INTO THE MOISTURE FEED
ALLOWING FOR BETTER CHANCES OF PRECIPITATION. CONTINUED ONSHORE FLOW
AHEAD OF THE SYSTEM WILL ALLOW FOR A WARMING LOW-LEVEL THERMAL
PROFILE SO ANY PRECIPITATION WILL BE LIQUID WITH SOME MIXING
POSSIBLE IN THE FAR NORTHWESTERN ZONES. IT IS ENTIRELY POSSIBLE THAT
A WEAK CAD SETUP OCCURS LATE MONDAY NIGHT WITH A NORTHERLY BOUNDARY
LAYER AGEOSTROPHIC WIND COMPONENT. MODELS HAVE BEEN KNOWN TO WARM
THE SURFACE LAYER TOO FAST WITH A RATHER LARGE NEW ENGLAND HIGH
PRESSURE IN PLACE, OR THEY PUSH THE HIGH OUT FASTER ALLOWING A
SOUTHEAST RETURN FLOW. EITHER WAY IT COULD BE A MESSY TUESDAY
MORNING COMMUTE ACROSS OUR NORTHWEST ZONES. SYSTEM MOVES OFF TOWARDS
THE NORTHEAST ON TUESDAY, WITH RAIN STILL ONGOING, BUT WE ARE
GEARING UP FOR THE BIGGER EVENT ON CHRISTMAS EVE.

WEDNESDAY...STILL WATCHING A LARGE LOW PRESSURE FORM TO OUR WEST AND
TRACK INTO THE GREAT LAKES REGION ON WEDNESDAY. THIS WOULD KEEP OUR
REGION UNDER A WARMING THERMAL PROFILE WITH A LOT OF MOISTURE TO
WORK WITH...AN ALL LIQUID EVENT IS EXPECTED AT THIS POINT. GUIDANCE
CONTINUES TO SHOW A WEAKER SECONDARY DEVELOPMENT ALONG A TRIPLE
POINT OVER OUR REGION DURING THE DAY. THIS WOULD HELP TO INTENSIFY
RAINFALL AMOUNTS AND ENHANCE THE LOW-LEVEL PRESSURE GRADIENT. HEAVY
RAIN WITH STRONG WINDS ARE EXPECTED SO IT IS ENTIRELY POSSIBLE WE
ARE LOOKING AT ANOTHER MULTIPLE HEADLINE EVENT. COASTAL FLOODING
COULD ALSO BECOME AN ISSUE WITH THE STRONGER ONSHORE WINDS DURING
WEDNESDAY`S HIGH TIDE. HAVE GONE WITH CATEGORICAL POPS FOR THAIS
TIMEFRAME. WE WILL CONTINUE TO HAVE WORDING IN THE HWO FOR THIS
EVENT. LOOKS LIKE RUDOLPH AND THE OTHER REINDEER WILL HAVE THEIR
WORK CUT OUT FOR THEM THIS CHRISTMAS EVE.

&&

.AVIATION /09Z FRIDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

MOSTLY VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD. THERE
SHOULD BE PERSISTENT CLOUDS BETWEEN 3000 AND 5000 FT AGL FOR MUCH OF
THE DAY, SO COULD SEE LOCALIZED MVFR CEILINGS RIGHT AT 3000 FT, BUT
MOSTLY CEILINGS SHOULD BE BETWEEN 3500 AND 4000 FT. NORTHWESTERLY
WINDS MAY GUST AT TIMES TO 20KT THROUGH EARLY THIS AFTERNOON, BUT BY
TONIGHT SHOULD BE LESS THAN 10KT.

OUTLOOK...
SATURDAY - SUNDAY...VFR. NORTH-NORTHEAST WINDS EXPECTED. CIGS COULD BE
LOWERING THROUGHOUT THE DAY

MONDAY - TUESDAY...SUB-VFR EXPECTED WITH SCATTERED RAIN/SNOW
SHOWERS, BECOMING ALL RAIN BY TUESDAY.

&&

.MARINE...
WINDS AND SEAS SHOULD STAY BELOW SCA CRITERIA. HOWEVER, GUSTS NEAR
OR JUST ABOVE 20KT WILL BE POSSIBLE THROUGH THIS EVENING.

OUTLOOK...
SATURDAY - SUNDAY...SUB-SCA EXPECTED FOR THE MOST PART. SEAS REMAIN
AROUND 3 TO 4 FEET.  CONFIDENCE: AVERAGE TO SLIGHTLY BELOW AVERAGE.

MONDAY - TUESDAY...SCA CONDITIONS SHOULD PRESENT THEMSELVES LATER ON MONDAY
UNDER A STRENGTHENING EASTERLY FLOW AND BUILDING SEAS. CONFIDENCE:
AVERAGE.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...GIGI
NEAR TERM...JOHNSON
SHORT TERM...JOHNSON
LONG TERM...HEAVENER
AVIATION...HEAVENER/JOHNSON
MARINE...HEAVENER/JOHNSON







000
FXUS61 KPHI 190924
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
424 AM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE OVER THE NORTHERN GREAT LAKES WILL MOVE INTO THE OHIO
VALLEY THIS MORNING. LOW PRESSURE IS EXPECTED TO FORM OVER THE GULF
STATES LATE TONIGHT AND TRACK ACROSS GEORGIA SATURDAY. A STRONG LOW
PRESSURE SYSTEM AND COLD FRONT MAY MOVE THROUGH THE EASTERN SEABOARD ON
CHRISTMAS EVE.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SURFACE HIGH CONTINUES TO SLIDE CLOSER TO THE REGION TODAY. HOWEVER,
LIKE LAST WEEK, THERE APPEARS TO BE ABUNDANT MOISTURE BELOW THE
INVERSION, SO DESPITE THE SYNOPTIC SCALE SUBSIDENCE, SHOULD STILL
SEE QUITE A BIT OF CLOUD COVER. WITH LITTLE CHANGE IN THE AIR MASS,
EXPECT HIGHS NEAR MAX TEMPS YESTERDAY WHICH ARE NEAR OR JUST BELOW
NORMALS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
THE BIGGEST CHANGE TONIGHT FROM THE LAST FEW NIGHTS IS THAT WITH THE
HIGH INCHING CLOSER AND THUS THE PRESSURE GRADIENT ACROSS THE REGION
DECREASING, WINDS SHOULD BE LIGHT. THOUGH WE WOULD TYPICALLY EXPECT
TO SEE CLEARING SKIES IN THIS PATTERN, WITH THE LOW LEVEL MOISTURE
LIKELY STILL IN PLACE, COULD STILL SEE QUITE A BIT OF CLOUD COVER,
ESPECIALLY OVER THE NORTHERN HALF OF THE REGION.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
MID-LEVEL FLOW THE NEXT COUPLE OF DAYS IS RATHER FLAT THOUGH A
CHANGE TO THAT PATTERN APPEARS LIKELY BY THE END OF THE WEEKEND. A
DEEP TROUGH EMERGES ACROSS THE CENTRAL U.S. BY TUESDAY AS MULTIPLE
PACIFIC NORTHWEST WAVES ROUND THE BASE OF THE TROUGH AND ACROSS OUR
REGION...WE ARE HEADING FOR A VERY UNSETTLED PERIOD BY EARLY NEXT
WEEK.

SATURDAY - SUNDAY...LOOKS MOSTLY DRY BOTH DAYS WITH HIGH PRESSURE
ANCHORED TO OUR NORTHEAST. THERE IS SOME NORTHERN STREAM ENERGY TO
CONTEND WITH LATE SATURDAY NIGHT WITH THE HELP OF A WEAK INVERTED
TROUGH OFFSHORE. THIS COMBINATION COULD TOUCH OFF A FEW SHOWERS AS
ALONG THE NORTHEASTERN NEW JERSEY COAST BUT WILL BE OF LITTLE
CONSEQUENCE. ONSHORE FLOW WILL HELP TO KEEP AMPLE LOW-LEVEL MOISTURE
STREAMING INTO THE REGION, UNDER THE SUBSIDENCE INVERSION. SATURDAY
COULD BE THE SUNNIER DAY THAN SUNDAY, BUT EACH DAY THE CONVECTIVE
TEMPERATURES LOOK TO BE REACHED SO IT MAY BE SHORT LIVED.

MONDAY - TUESDAY...ONCE THE AFOREMENTIONED SYSTEM ABOVE DEPARTS
ANOTHER, BETTER DEFINED SYSTEM MOVES OFF THE CAROLINA COAST AND OUT
TO SEA ON TUESDAY. WEAK BAROCLINIC ZONE OFF THE MID-ATLANTIC COAST
WILL ALLOW FOR AMPLE MOISTURE TO ADVECT IN FROM THE SOUTH. AS THE
WAVE OF LOW PRESSURE MOVES BY IT WILL TAP INTO THE MOISTURE FEED
ALLOWING FOR BETTER CHANCES OF PRECIPITATION. CONTINUED ONSHORE FLOW
AHEAD OF THE SYSTEM WILL ALLOW FOR A WARMING LOW-LEVEL THERMAL
PROFILE SO ANY PRECIPITATION WILL BE LIQUID WITH SOME MIXING
POSSIBLE IN THE FAR NORTHWESTERN ZONES. IT IS ENTIRELY POSSIBLE THAT
A WEAK CAD SETUP OCCURS LATE MONDAY NIGHT WITH A NORTHERLY BOUNDARY
LAYER AGEOSTROPHIC WIND COMPONENT. MODELS HAVE BEEN KNOWN TO WARM
THE SURFACE LAYER TOO FAST WITH A RATHER LARGE NEW ENGLAND HIGH
PRESSURE IN PLACE, OR THEY PUSH THE HIGH OUT FASTER ALLOWING A
SOUTHEAST RETURN FLOW. EITHER WAY IT COULD BE A MESSY TUESDAY
MORNING COMMUTE ACROSS OUR NORTHWEST ZONES. SYSTEM MOVES OFF TOWARDS
THE NORTHEAST ON TUESDAY, WITH RAIN STILL ONGOING, BUT WE ARE
GEARING UP FOR THE BIGGER EVENT ON CHRISTMAS EVE.

WEDNESDAY...STILL WATCHING A LARGE LOW PRESSURE FORM TO OUR WEST AND
TRACK INTO THE GREAT LAKES REGION ON WEDNESDAY. THIS WOULD KEEP OUR
REGION UNDER A WARMING THERMAL PROFILE WITH A LOT OF MOISTURE TO
WORK WITH...AN ALL LIQUID EVENT IS EXPECTED AT THIS POINT. GUIDANCE
CONTINUES TO SHOW A WEAKER SECONDARY DEVELOPMENT ALONG A TRIPLE
POINT OVER OUR REGION DURING THE DAY. THIS WOULD HELP TO INTENSIFY
RAINFALL AMOUNTS AND ENHANCE THE LOW-LEVEL PRESSURE GRADIENT. HEAVY
RAIN WITH STRONG WINDS ARE EXPECTED SO IT IS ENTIRELY POSSIBLE WE
ARE LOOKING AT ANOTHER MULTIPLE HEADLINE EVENT. COASTAL FLOODING
COULD ALSO BECOME AN ISSUE WITH THE STRONGER ONSHORE WINDS DURING
WEDNESDAY`S HIGH TIDE. HAVE GONE WITH CATEGORICAL POPS FOR THAIS
TIMEFRAME. WE WILL CONTINUE TO HAVE WORDING IN THE HWO FOR THIS
EVENT. LOOKS LIKE RUDOLPH AND THE OTHER REINDEER WILL HAVE THEIR
WORK CUT OUT FOR THEM THIS CHRISTMAS EVE.

&&

.AVIATION /09Z FRIDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

MOSTLY VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD. THERE
SHOULD BE PERSISTENT CLOUDS BETWEEN 3000 AND 5000 FT AGL FOR MUCH OF
THE DAY, SO COULD SEE LOCALIZED MVFR CEILINGS RIGHT AT 3000 FT, BUT
MOSTLY CEILINGS SHOULD BE BETWEEN 3500 AND 4000 FT. NORTHWESTERLY
WINDS MAY GUST AT TIMES TO 20KT THROUGH EARLY THIS AFTERNOON, BUT BY
TONIGHT SHOULD BE LESS THAN 10KT.

OUTLOOK...
SATURDAY - SUNDAY...VFR. NORTH-NORTHEAST WINDS EXPECTED. CIGS COULD BE
LOWERING THROUGHOUT THE DAY

MONDAY - TUESDAY...SUB-VFR EXPECTED WITH SCATTERED RAIN/SNOW
SHOWERS, BECOMING ALL RAIN BY TUESDAY.

&&

.MARINE...
WINDS AND SEAS SHOULD STAY BELOW SCA CRITERIA. HOWEVER, GUSTS NEAR
OR JUST ABOVE 20KT WILL BE POSSIBLE THROUGH THIS EVENING.

OUTLOOK...
SATURDAY - SUNDAY...SUB-SCA EXPECTED FOR THE MOST PART. SEAS REMAIN
AROUND 3 TO 4 FEET.  CONFIDENCE: AVERAGE TO SLIGHTLY BELOW AVERAGE.

MONDAY - TUESDAY...SCA CONDITIONS SHOULD PRESENT THEMSELVES LATER ON MONDAY
UNDER A STRENGTHENING EASTERLY FLOW AND BUILDING SEAS. CONFIDENCE:
AVERAGE.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...GIGI
NEAR TERM...JOHNSON
SHORT TERM...JOHNSON
LONG TERM...HEAVENER
AVIATION...HEAVENER/JOHNSON
MARINE...HEAVENER/JOHNSON






000
FXUS61 KPBZ 190839
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
339 AM EST FRI DEC 19 2014

.SYNOPSIS...
A WEAK DISTURBANCE WILL CROSS THE REGION TONIGHT. BUILDING HIGH
PRESSURE IS EXPECTED THROUGH THE WEEKEND...THOUGH CLOUDS WILL
REMAIN.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CURRENTLY TWO DIFFERENT TYPES OF PRECIPITATION BEING GENERATED
PRODUCED BY TWO DIFFERENT MODES OF GENERATION. LIGHT SNOW SHOWERS
EXIST ACROSS THE SOUTH AND HIGHER ELEVATIONS OF THE SOUTHEAST
PRODUCED BY SEEDER-FEEDER METHODS WITH MOISTURE FROM ABOUT
500MB-600MB SEEDING THE MOISTURE TRAPPED BELOW THE INVERSION AT
850MB. THE 00Z UPPER AIR SOUNDING SAMPLED THIS ENVIRONMENT RATHER
NICELY AND THE HI-RES MODELS HAVE PICKED UP ON THIS...EVEN
GENERATING QPF. AS THE SW TROF AXIS SWINGS THROUGH N TO S THE UPPER
LEVEL MOISTURE MOVES QUICKLY OUT WHILE DRYING UP. THIS SHOULD
EFFECTIVELY SQUASH ANY REMAINING SEEDER-FEEDER GENERATED SNOW
SHOWERS ACROSS OUR SOUTH.

ELSEWHERE...ACROSS THE NORTHERN TIER OF THE CWA THE BL MOISTURE
DEPTH HAS BEEN ENHANCED BY AN INJECTION OF UPSTREAM LAKE MOISTURE
THAT HAS RAISED INVERSION HEIGHTS. LAST NIGHT MODELS WERE INDICATING
A BL TOP TEMP IN THE -10C TO -11C RANGE WHICH WOULD BE COLD ENOUGH
TO PRODUCE ICE CRYSTALS AND GENERATE LIGHT SNOW. THE 00Z SOUNDING
VERIFIED THIS OCCURRENCE WITH 850MB TEMPS RIGHT AT -10C...WHICH WOULD
LEAD ONE TO BELIEVE THAT SNOW WOULD RESULT. HOWEVER...LOOKING AT RAP
BUFR SOUNDINGS...THE -10C ISOTHERM LAYER IS RATHER SMALL SPATIALLY
AT 850MB AND THE SAMPLE TAKE SEEMS MORE LIKE THE EXCEPTION THAN THE
RULE. IN ACTUALITY THE BL TOP TEMP IS CLOSER TO -8C WHICH KEEPS
SUPERCOOLED LIQUID INTO PLAY...THUS THE REPORTS OF FZDZ MIXING IN
WITH LIGHT SNOW. AN ADVISORY IS OUT FOR THE AREA DIRECTLY IMPACTED
BY THE FZDZ...AND DEPENDING ON THE DRIFT OF THE DOWN-LAKE
MOISTURE...AN EXPANSION SOUTHWARD MAY BE NECESSARY.

HI-RES MODELS INDICATING A FEED OF ENHANCED LLVL MOISTURE WILL SAG
SOUTHWARD THROUGH THE EARLY MORNING HOURS...REACHING THE PITTSBURGH
METRO AREA NEAR SUNRISE. THIS IS IN RESPONSE TO THE MI-LEVEL TROF
AXIS AND ATTENDANT MID-LEVEL DEFORMATION ZONE. AS IT CONTINUES IT
TREK SOUTH OF LAKE ERIE...THE MOISTURE BEGINS TO ERODE ALONG WITH
THE DEFORMATION ZONE GETTING WASHED OUT. ATTM...HAVE INCLUDED LIGHT
SNOW SHOWERS INTO THE METRO AND AREAS NW TO SE SURROUNDING. WILL SHY
AWAY FROM FZDZ MENTION FOR NOW...AS CONFIDENCE IS NOT HIGH IN THE
POTENTIAL FURTHER SOUTH. CLOUDS WILL CONTINUE TO PLAGUE THE CWA FOR
YET ANOTHER DAY.
TAX

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
SFC HIGH PRES IS PROGGED TO BLD IN UNDER UPR TROFG OVR THE GT LKS
FRI...ENDING ANY LINGERING MRNG SNW SHWRS. THE SFC HIGH IS EXPD TO
BRING DRY WEA THRU THE WKEND...THOUGH PERSISTENT MSTR BLO AN
INVERSION MAY KEEP SKIES MCLDY. A SHRTWV MOVG ACRS THE SERN CONUS
LT SAT/SAT NGT IS NOW PROGGED TO STAY FAR ENOUGH S TO REMOVE ALL
PCPN FM THE FCST FOR AREAS S OF PIT. A WK SHRTWV IS PROGGED FOR
ERLY SUN ACRS THE GT LKS...BUT WITH A LACK OF DEEP MSTR AND THE
SFC HIGH OVERHEAD KEPT THE FCST DRY.

SLGTLY BLO AVG TEMPS SHOULD RTN TO NR SEASONAL LVLS BY SUN.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
WHILE THE MODELS AGREE ON A DEEPENING UPPER LEVEL TROUGH TO CLOSE
OFF OVER THE GREAT LAKES THROUGH THE PERIOD THE DETAILS OF HOW
THIS EXACTLY UNFOLDS WILL BE CRITICAL. BY MONDAY SOUTHERN STREAM
SHORTWAVE AHEAD OF MAIN NORTHERN STREAM UPPER TROUGH DIGGING INTO
THE NORTHERN PLAINS WILL PRODUCE LOW PRESSURE ACROSS THE CAROLINAS
MOVING OFF SHORE OF THE EAST COAST. THE SOUTHEAST RIDGES MAY BE
BRUSHED BY LIGHT RAIN FROM THIS SYSTEM. NEXT UP IS DEEPENING LOW
PRESSURE OVER THE OHIO VALLEY AHEAD OF SHARPLY DIGGING UPPER
TROUGH AND CLOSED LOW MOVING INTO THE WESTERN GREAT LAKES. UPPER
OHIO VALLEY LOOKS TO BE ON THE WARM SIDE OF THE SYSTEM TUESDAY
INTO WEDNESDAY WITH RAIN...FOLLOWED BY STRONG COLD FRONT AND COLD
ADVECTION LATER WEDNESDAY NIGHT AND THURSDAY WITH SNOW SHOWERS.
WITH SUCH A STRONG SYSTEM ALOFT AND FAST DEEPENING LOW PRESSURE AT
THE SURFACE TIMING OF COLD AIR AND EXACT TRACK WILL LIKELY CHANGE
AS WE GET CLOSER TO CHRISTMAS. ALL IN ALL PREVIOUS FORECAST IS
LITTLE CHANGED WITH ONLY MINOR ADJUSTMENTS BASED ON NEWEST WPC
EXTENDED PROGS.

&&

.AVIATION /09Z FRIDAY THROUGH TUESDAY/...
UPDATED TAFS TO INCLUDE MENTION OF FREEZING DRIZZLE FOR SITES
NORTH OF INTERSTATE 70 THROUGH EARLY THIS MORNING BASED ON LATEST
OBS AND LATEST HI RES AND RAPID REFRESH GUIDANCE SHOWING
INDICATING MOISTURE IN THE COLUMN LIMITED TO LOWER LEVELS NOT COLD
ENOUGH FOR ICE CRYSTAL FORMATION...THUS...FINE MIST AND LIGHT
DRIZZLE EXPECTED THROUGH 9AM WILL REMAIN LIQUID AND FREEZE ON
CONTACT. DO NOT EXPECT ANY PERIODS OF RAPID ICE DEVELOPMENT BUT
WILL LIKELY FOR A LIGHT GLAZE OVER THE NEXT SEVERAL HOURS.
ICE POTENTIAL WILL LIKELY BE OVER BY MID MORNING AS MOISTURE POOL
BECOMES TOO SHALLOW...WITH CIG RESTRICTIONS LARGELY MVFR THROUGH
MUCH OF THE DAY...IMPROVING TO VFR STARTING LATE THIS AFTERNOON.


OUTLOOK.../FRIDAY NIGHT THROUGH TUESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR
     OHZ039>041-048>050.
PA...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR
     PAZ007>009-013>016-020>022.
WV...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR WVZ001.

&&

$$






000
FXUS61 KPBZ 190839
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
339 AM EST FRI DEC 19 2014

.SYNOPSIS...
A WEAK DISTURBANCE WILL CROSS THE REGION TONIGHT. BUILDING HIGH
PRESSURE IS EXPECTED THROUGH THE WEEKEND...THOUGH CLOUDS WILL
REMAIN.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CURRENTLY TWO DIFFERENT TYPES OF PRECIPITATION BEING GENERATED
PRODUCED BY TWO DIFFERENT MODES OF GENERATION. LIGHT SNOW SHOWERS
EXIST ACROSS THE SOUTH AND HIGHER ELEVATIONS OF THE SOUTHEAST
PRODUCED BY SEEDER-FEEDER METHODS WITH MOISTURE FROM ABOUT
500MB-600MB SEEDING THE MOISTURE TRAPPED BELOW THE INVERSION AT
850MB. THE 00Z UPPER AIR SOUNDING SAMPLED THIS ENVIRONMENT RATHER
NICELY AND THE HI-RES MODELS HAVE PICKED UP ON THIS...EVEN
GENERATING QPF. AS THE SW TROF AXIS SWINGS THROUGH N TO S THE UPPER
LEVEL MOISTURE MOVES QUICKLY OUT WHILE DRYING UP. THIS SHOULD
EFFECTIVELY SQUASH ANY REMAINING SEEDER-FEEDER GENERATED SNOW
SHOWERS ACROSS OUR SOUTH.

ELSEWHERE...ACROSS THE NORTHERN TIER OF THE CWA THE BL MOISTURE
DEPTH HAS BEEN ENHANCED BY AN INJECTION OF UPSTREAM LAKE MOISTURE
THAT HAS RAISED INVERSION HEIGHTS. LAST NIGHT MODELS WERE INDICATING
A BL TOP TEMP IN THE -10C TO -11C RANGE WHICH WOULD BE COLD ENOUGH
TO PRODUCE ICE CRYSTALS AND GENERATE LIGHT SNOW. THE 00Z SOUNDING
VERIFIED THIS OCCURRENCE WITH 850MB TEMPS RIGHT AT -10C...WHICH WOULD
LEAD ONE TO BELIEVE THAT SNOW WOULD RESULT. HOWEVER...LOOKING AT RAP
BUFR SOUNDINGS...THE -10C ISOTHERM LAYER IS RATHER SMALL SPATIALLY
AT 850MB AND THE SAMPLE TAKE SEEMS MORE LIKE THE EXCEPTION THAN THE
RULE. IN ACTUALITY THE BL TOP TEMP IS CLOSER TO -8C WHICH KEEPS
SUPERCOOLED LIQUID INTO PLAY...THUS THE REPORTS OF FZDZ MIXING IN
WITH LIGHT SNOW. AN ADVISORY IS OUT FOR THE AREA DIRECTLY IMPACTED
BY THE FZDZ...AND DEPENDING ON THE DRIFT OF THE DOWN-LAKE
MOISTURE...AN EXPANSION SOUTHWARD MAY BE NECESSARY.

HI-RES MODELS INDICATING A FEED OF ENHANCED LLVL MOISTURE WILL SAG
SOUTHWARD THROUGH THE EARLY MORNING HOURS...REACHING THE PITTSBURGH
METRO AREA NEAR SUNRISE. THIS IS IN RESPONSE TO THE MI-LEVEL TROF
AXIS AND ATTENDANT MID-LEVEL DEFORMATION ZONE. AS IT CONTINUES IT
TREK SOUTH OF LAKE ERIE...THE MOISTURE BEGINS TO ERODE ALONG WITH
THE DEFORMATION ZONE GETTING WASHED OUT. ATTM...HAVE INCLUDED LIGHT
SNOW SHOWERS INTO THE METRO AND AREAS NW TO SE SURROUNDING. WILL SHY
AWAY FROM FZDZ MENTION FOR NOW...AS CONFIDENCE IS NOT HIGH IN THE
POTENTIAL FURTHER SOUTH. CLOUDS WILL CONTINUE TO PLAGUE THE CWA FOR
YET ANOTHER DAY.
TAX

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
SFC HIGH PRES IS PROGGED TO BLD IN UNDER UPR TROFG OVR THE GT LKS
FRI...ENDING ANY LINGERING MRNG SNW SHWRS. THE SFC HIGH IS EXPD TO
BRING DRY WEA THRU THE WKEND...THOUGH PERSISTENT MSTR BLO AN
INVERSION MAY KEEP SKIES MCLDY. A SHRTWV MOVG ACRS THE SERN CONUS
LT SAT/SAT NGT IS NOW PROGGED TO STAY FAR ENOUGH S TO REMOVE ALL
PCPN FM THE FCST FOR AREAS S OF PIT. A WK SHRTWV IS PROGGED FOR
ERLY SUN ACRS THE GT LKS...BUT WITH A LACK OF DEEP MSTR AND THE
SFC HIGH OVERHEAD KEPT THE FCST DRY.

SLGTLY BLO AVG TEMPS SHOULD RTN TO NR SEASONAL LVLS BY SUN.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
WHILE THE MODELS AGREE ON A DEEPENING UPPER LEVEL TROUGH TO CLOSE
OFF OVER THE GREAT LAKES THROUGH THE PERIOD THE DETAILS OF HOW
THIS EXACTLY UNFOLDS WILL BE CRITICAL. BY MONDAY SOUTHERN STREAM
SHORTWAVE AHEAD OF MAIN NORTHERN STREAM UPPER TROUGH DIGGING INTO
THE NORTHERN PLAINS WILL PRODUCE LOW PRESSURE ACROSS THE CAROLINAS
MOVING OFF SHORE OF THE EAST COAST. THE SOUTHEAST RIDGES MAY BE
BRUSHED BY LIGHT RAIN FROM THIS SYSTEM. NEXT UP IS DEEPENING LOW
PRESSURE OVER THE OHIO VALLEY AHEAD OF SHARPLY DIGGING UPPER
TROUGH AND CLOSED LOW MOVING INTO THE WESTERN GREAT LAKES. UPPER
OHIO VALLEY LOOKS TO BE ON THE WARM SIDE OF THE SYSTEM TUESDAY
INTO WEDNESDAY WITH RAIN...FOLLOWED BY STRONG COLD FRONT AND COLD
ADVECTION LATER WEDNESDAY NIGHT AND THURSDAY WITH SNOW SHOWERS.
WITH SUCH A STRONG SYSTEM ALOFT AND FAST DEEPENING LOW PRESSURE AT
THE SURFACE TIMING OF COLD AIR AND EXACT TRACK WILL LIKELY CHANGE
AS WE GET CLOSER TO CHRISTMAS. ALL IN ALL PREVIOUS FORECAST IS
LITTLE CHANGED WITH ONLY MINOR ADJUSTMENTS BASED ON NEWEST WPC
EXTENDED PROGS.

&&

.AVIATION /09Z FRIDAY THROUGH TUESDAY/...
UPDATED TAFS TO INCLUDE MENTION OF FREEZING DRIZZLE FOR SITES
NORTH OF INTERSTATE 70 THROUGH EARLY THIS MORNING BASED ON LATEST
OBS AND LATEST HI RES AND RAPID REFRESH GUIDANCE SHOWING
INDICATING MOISTURE IN THE COLUMN LIMITED TO LOWER LEVELS NOT COLD
ENOUGH FOR ICE CRYSTAL FORMATION...THUS...FINE MIST AND LIGHT
DRIZZLE EXPECTED THROUGH 9AM WILL REMAIN LIQUID AND FREEZE ON
CONTACT. DO NOT EXPECT ANY PERIODS OF RAPID ICE DEVELOPMENT BUT
WILL LIKELY FOR A LIGHT GLAZE OVER THE NEXT SEVERAL HOURS.
ICE POTENTIAL WILL LIKELY BE OVER BY MID MORNING AS MOISTURE POOL
BECOMES TOO SHALLOW...WITH CIG RESTRICTIONS LARGELY MVFR THROUGH
MUCH OF THE DAY...IMPROVING TO VFR STARTING LATE THIS AFTERNOON.


OUTLOOK.../FRIDAY NIGHT THROUGH TUESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR
     OHZ039>041-048>050.
PA...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR
     PAZ007>009-013>016-020>022.
WV...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR WVZ001.

&&

$$







000
FXUS61 KPBZ 190743
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
243 AM EST FRI DEC 19 2014

.SYNOPSIS...
A WEAK DISTURBANCE WILL CROSS THE REGION TONIGHT. BUILDING HIGH
PRESSURE IS EXPECTED THROUGH THE WEEKEND...THOUGH CLOUDS WILL
REMAIN.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CURRENTLY TWO DIFFERENT TYPES OF PRECIPITATION BEING GENERATED
PRODUCED BY TWO DIFFERENT MODES OF GENERATION. LIGHT SNOW SHOWERS
EXIST ACROSS THE SOUTH AND HIGHER ELEVATIONS OF THE SOUTHEAST
PRODUCED BY SEEDER-FEEDER METHODS WITH MOISTURE FROM ABOUT
500MB-600MB SEEDING THE MOISTURE TRAPPED BELOW THE INVERSION AT
850MB. THE 00Z UPPER AIR SOUNDING SAMPLED THIS ENVIRONMENT RATHER
NICELY AND THE HI-RES MODELS HAVE PICKED UP ON THIS...EVEN
GENERATING QPF. AS THE SW TROF AXIS SWINGS THROUGH N TO S THE UPPER
LEVEL MOISTURE MOVES QUICKLY OUT WHILE DRYING UP. THIS SHOULD
EFFECTIVELY SQUASH ANY REMAINING SEEDER-FEEDER GENERATED SNOW
SHOWERS ACROSS OUR SOUTH.

ELSEWHERE...ACROSS THE NORTHERN TIER OF THE CWA THE BL MOISTURE
DEPTH HAS BEEN ENHANCED BY AN INJECTION OF UPSTREAM LAKE MOISTURE
THAT HAS RAISED INVERSION HEIGHTS. LAST NIGHT MODELS WERE INDICATING
A BL TOP TEMP IN THE -10C TO -11C RANGE WHICH WOULD BE COLD ENOUGH
TO PRODUCE ICE CRYSTALS AND GENERATE LIGHT SNOW. THE 00Z SOUNDING
VERIFIED THIS OCCURRENCE WITH 850MB TEMPS RIGHT AT -10C...WHICH WOULD
LEAD ONE TO BELIEVE THAT SNOW WOULD RESULT. HOWEVER...LOOKING AT RAP
BUFR SOUNDINGS...THE -10C ISOTHERM LAYER IS RATHER SMALL SPATIALLY
AT 850MB AND THE SAMPLE TAKE SEEMS MORE LIKE THE EXCEPTION THAN THE
RULE. IN ACTUALITY THE BL TOP TEMP IS CLOSER TO -8C WHICH KEEPS
SUPERCOOLED LIQUID INTO PLAY...THUS THE REPORTS OF FZDZ MIXING IN
WITH LIGHT SNOW. AN ADVISORY IS OUT FOR THE AREA DIRECTLY IMPACTED
BY THE FZDZ...AND DEPENDING ON THE DRIFT OF THE DOWN-LAKE
MOISTURE...AN EXPANSION SOUTHWARD MAY BE NECESSARY.

HI-RES MODELS INDICATING A FEED OF ENHANCED LLVL MOISTURE WILL SAG
SOUTHWARD THROUGH THE EARLY MORNING HOURS...REACHING THE PITTSBURGH
METRO AREA NEAR SUNRISE. THIS IS IN RESPONSE TO THE MI-LEVEL TROF
AXIS AND ATTENDANT MID-LEVEL DEFORMATION ZONE. AS IT CONTINUES IT
TREK SOUTH OF LAKE ERIE...THE MOISTURE BEGINS TO ERODE ALONG WITH
THE DEFORMATION ZONE GETTING WASHED OUT. ATTM...HAVE INCLUDED LIGHT
SNOW SHOWERS INTO THE METRO AND AREAS NW TO SE SURROUNDING. WILL SHY
AWAY FROM FZDZ MENTION FOR NOW...AS CONFIDENCE IS NOT HIGH IN THE
POTENTIAL FURTHER SOUTH. CLOUDS WILL CONTINUE TO PLAGUE THE CWA FOR
YET ANOTHER DAY.
TAX

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
SFC HIGH PRES IS PROGGED TO BLD IN UNDER UPR TROFG OVR THE GT LKS
FRI...ENDING ANY LINGERING MRNG SNW SHWRS. THE SFC HIGH IS EXPD TO
BRING DRY WEA THRU THE WKEND...THOUGH PERSISTENT MSTR BLO AN
INVERSION MAY KEEP SKIES MCLDY. A SHRTWV MOVG ACRS THE SERN CONUS
LT SAT/SAT NGT IS NOW PROGGED TO STAY FAR ENOUGH S TO REMOVE ALL
PCPN FM THE FCST FOR AREAS S OF PIT. A WK SHRTWV IS PROGGED FOR
ERLY SUN ACRS THE GT LKS...BUT WITH A LACK OF DEEP MSTR AND THE
SFC HIGH OVERHEAD KEPT THE FCST DRY.

SLGTLY BLO AVG TEMPS SHOULD RTN TO NR SEASONAL LVLS BY SUN.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
WHILE THE MODELS AGREE ON A DEEPENING UPPER LEVEL TROUGH TO CLOSE
OFF OVER THE GREAT LAKES THROUGH THE PERIOD THE DETAILS OF HOW
THIS EXACTLY UNFOLDS WILL BE CRITICAL. BY MONDAY SOUTHERN STREAM
SHORTWAVE AHEAD OF MAIN NORTHERN STREAM UPPER TROUGH DIGGING INTO
THE NORTHERN PLAINS WILL PRODUCE LOW PRESSURE ACROSS THE CAROLINAS
MOVING OFF SHORE OF THE EAST COAST. THE SOUTHEAST RIDGES MAY BE
BRUSHED BY LIGHT RAIN FROM THIS SYSTEM. NEXT UP IS DEEPENING LOW
PRESSURE OVER THE OHIO VALLEY AHEAD OF SHARPLY DIGGING UPPER
TROUGH AND CLOSED LOW MOVING INTO THE WESTERN GREAT LAKES. UPPER
OHIO VALLEY LOOKS TO BE ON THE WARM SIDE OF THE SYSTEM TUESDAY
INTO WEDNESDAY WITH RAIN...FOLLOWED BY STRONG COLD FRONT AND COLD
ADVECTION LATER WEDNESDAY NIGHT AND THURSDAY WITH SNOW SHOWERS.
WITH SUCH A STRONG SYSTEM ALOFT AND FAST DEEPENING LOW PRESSURE AT
THE SURFACE TIMING OF COLD AIR AND EXACT TRACK WILL LIKELY CHANGE
AS WE GET CLOSER TO CHRISTMAS. ALL IN ALL PREVIOUS FORECAST IS
LITTLE CHANGED WITH ONLY MINOR ADJUSTMENTS BASED ON NEWEST WPC
EXTENDED PROGS.

&&

.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
MVFR CIGS EXPECTED OVERNIGHT WITH SITES ALONG AND NORTH OF
INTERSTATE 80 POTENTIALLY SEEING IFR CIGS DEVELOP DURING PERIODS
OF LIGHT SNOW. THERE IS A SLIGHT CHANCE THAT LIGHT FREEZING
DRIZZLE MAY OCCUR AND SPREAD FROM NORTH TO SOUTH OVERNIGHT AS
MOISTURE DECREASES ALOFT LEAVING ONLY LOW LEVEL MOISTURE IN PLACE
TRAPPED UNDER THE INVERSION IN TEMPERATURES NOT SUFFICIENTLY COLD
FOR ICE CRYSTALS TO DEVELOP...BUT CONFIDENCE IS NOT HIGH ENOUGH
TO INCLUDE IN TAFS AT THIS TIME. POTENTIAL FOR FREEZING DRIZZLE
WILL LIKELY BE OVER BY MID MORNING AS MOISTURE POOL BECOMES TOO
SHALLOW.


OUTLOOK.../FRIDAY NIGHT THROUGH TUESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR
     OHZ039>041-048>050.
PA...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR
     PAZ007>009-013>016-020>022.
WV...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR WVZ001.

&&

$$






000
FXUS61 KPBZ 190743
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
243 AM EST FRI DEC 19 2014

.SYNOPSIS...
A WEAK DISTURBANCE WILL CROSS THE REGION TONIGHT. BUILDING HIGH
PRESSURE IS EXPECTED THROUGH THE WEEKEND...THOUGH CLOUDS WILL
REMAIN.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CURRENTLY TWO DIFFERENT TYPES OF PRECIPITATION BEING GENERATED
PRODUCED BY TWO DIFFERENT MODES OF GENERATION. LIGHT SNOW SHOWERS
EXIST ACROSS THE SOUTH AND HIGHER ELEVATIONS OF THE SOUTHEAST
PRODUCED BY SEEDER-FEEDER METHODS WITH MOISTURE FROM ABOUT
500MB-600MB SEEDING THE MOISTURE TRAPPED BELOW THE INVERSION AT
850MB. THE 00Z UPPER AIR SOUNDING SAMPLED THIS ENVIRONMENT RATHER
NICELY AND THE HI-RES MODELS HAVE PICKED UP ON THIS...EVEN
GENERATING QPF. AS THE SW TROF AXIS SWINGS THROUGH N TO S THE UPPER
LEVEL MOISTURE MOVES QUICKLY OUT WHILE DRYING UP. THIS SHOULD
EFFECTIVELY SQUASH ANY REMAINING SEEDER-FEEDER GENERATED SNOW
SHOWERS ACROSS OUR SOUTH.

ELSEWHERE...ACROSS THE NORTHERN TIER OF THE CWA THE BL MOISTURE
DEPTH HAS BEEN ENHANCED BY AN INJECTION OF UPSTREAM LAKE MOISTURE
THAT HAS RAISED INVERSION HEIGHTS. LAST NIGHT MODELS WERE INDICATING
A BL TOP TEMP IN THE -10C TO -11C RANGE WHICH WOULD BE COLD ENOUGH
TO PRODUCE ICE CRYSTALS AND GENERATE LIGHT SNOW. THE 00Z SOUNDING
VERIFIED THIS OCCURRENCE WITH 850MB TEMPS RIGHT AT -10C...WHICH WOULD
LEAD ONE TO BELIEVE THAT SNOW WOULD RESULT. HOWEVER...LOOKING AT RAP
BUFR SOUNDINGS...THE -10C ISOTHERM LAYER IS RATHER SMALL SPATIALLY
AT 850MB AND THE SAMPLE TAKE SEEMS MORE LIKE THE EXCEPTION THAN THE
RULE. IN ACTUALITY THE BL TOP TEMP IS CLOSER TO -8C WHICH KEEPS
SUPERCOOLED LIQUID INTO PLAY...THUS THE REPORTS OF FZDZ MIXING IN
WITH LIGHT SNOW. AN ADVISORY IS OUT FOR THE AREA DIRECTLY IMPACTED
BY THE FZDZ...AND DEPENDING ON THE DRIFT OF THE DOWN-LAKE
MOISTURE...AN EXPANSION SOUTHWARD MAY BE NECESSARY.

HI-RES MODELS INDICATING A FEED OF ENHANCED LLVL MOISTURE WILL SAG
SOUTHWARD THROUGH THE EARLY MORNING HOURS...REACHING THE PITTSBURGH
METRO AREA NEAR SUNRISE. THIS IS IN RESPONSE TO THE MI-LEVEL TROF
AXIS AND ATTENDANT MID-LEVEL DEFORMATION ZONE. AS IT CONTINUES IT
TREK SOUTH OF LAKE ERIE...THE MOISTURE BEGINS TO ERODE ALONG WITH
THE DEFORMATION ZONE GETTING WASHED OUT. ATTM...HAVE INCLUDED LIGHT
SNOW SHOWERS INTO THE METRO AND AREAS NW TO SE SURROUNDING. WILL SHY
AWAY FROM FZDZ MENTION FOR NOW...AS CONFIDENCE IS NOT HIGH IN THE
POTENTIAL FURTHER SOUTH. CLOUDS WILL CONTINUE TO PLAGUE THE CWA FOR
YET ANOTHER DAY.
TAX

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
SFC HIGH PRES IS PROGGED TO BLD IN UNDER UPR TROFG OVR THE GT LKS
FRI...ENDING ANY LINGERING MRNG SNW SHWRS. THE SFC HIGH IS EXPD TO
BRING DRY WEA THRU THE WKEND...THOUGH PERSISTENT MSTR BLO AN
INVERSION MAY KEEP SKIES MCLDY. A SHRTWV MOVG ACRS THE SERN CONUS
LT SAT/SAT NGT IS NOW PROGGED TO STAY FAR ENOUGH S TO REMOVE ALL
PCPN FM THE FCST FOR AREAS S OF PIT. A WK SHRTWV IS PROGGED FOR
ERLY SUN ACRS THE GT LKS...BUT WITH A LACK OF DEEP MSTR AND THE
SFC HIGH OVERHEAD KEPT THE FCST DRY.

SLGTLY BLO AVG TEMPS SHOULD RTN TO NR SEASONAL LVLS BY SUN.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
WHILE THE MODELS AGREE ON A DEEPENING UPPER LEVEL TROUGH TO CLOSE
OFF OVER THE GREAT LAKES THROUGH THE PERIOD THE DETAILS OF HOW
THIS EXACTLY UNFOLDS WILL BE CRITICAL. BY MONDAY SOUTHERN STREAM
SHORTWAVE AHEAD OF MAIN NORTHERN STREAM UPPER TROUGH DIGGING INTO
THE NORTHERN PLAINS WILL PRODUCE LOW PRESSURE ACROSS THE CAROLINAS
MOVING OFF SHORE OF THE EAST COAST. THE SOUTHEAST RIDGES MAY BE
BRUSHED BY LIGHT RAIN FROM THIS SYSTEM. NEXT UP IS DEEPENING LOW
PRESSURE OVER THE OHIO VALLEY AHEAD OF SHARPLY DIGGING UPPER
TROUGH AND CLOSED LOW MOVING INTO THE WESTERN GREAT LAKES. UPPER
OHIO VALLEY LOOKS TO BE ON THE WARM SIDE OF THE SYSTEM TUESDAY
INTO WEDNESDAY WITH RAIN...FOLLOWED BY STRONG COLD FRONT AND COLD
ADVECTION LATER WEDNESDAY NIGHT AND THURSDAY WITH SNOW SHOWERS.
WITH SUCH A STRONG SYSTEM ALOFT AND FAST DEEPENING LOW PRESSURE AT
THE SURFACE TIMING OF COLD AIR AND EXACT TRACK WILL LIKELY CHANGE
AS WE GET CLOSER TO CHRISTMAS. ALL IN ALL PREVIOUS FORECAST IS
LITTLE CHANGED WITH ONLY MINOR ADJUSTMENTS BASED ON NEWEST WPC
EXTENDED PROGS.

&&

.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
MVFR CIGS EXPECTED OVERNIGHT WITH SITES ALONG AND NORTH OF
INTERSTATE 80 POTENTIALLY SEEING IFR CIGS DEVELOP DURING PERIODS
OF LIGHT SNOW. THERE IS A SLIGHT CHANCE THAT LIGHT FREEZING
DRIZZLE MAY OCCUR AND SPREAD FROM NORTH TO SOUTH OVERNIGHT AS
MOISTURE DECREASES ALOFT LEAVING ONLY LOW LEVEL MOISTURE IN PLACE
TRAPPED UNDER THE INVERSION IN TEMPERATURES NOT SUFFICIENTLY COLD
FOR ICE CRYSTALS TO DEVELOP...BUT CONFIDENCE IS NOT HIGH ENOUGH
TO INCLUDE IN TAFS AT THIS TIME. POTENTIAL FOR FREEZING DRIZZLE
WILL LIKELY BE OVER BY MID MORNING AS MOISTURE POOL BECOMES TOO
SHALLOW.


OUTLOOK.../FRIDAY NIGHT THROUGH TUESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR
     OHZ039>041-048>050.
PA...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR
     PAZ007>009-013>016-020>022.
WV...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR WVZ001.

&&

$$







000
FXUS61 KCTP 190641
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
141 AM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE OVER THE GREAT LAKES WILL SLIDE EAST INTO
PENNSYLVANIA THIS WEEKEND. AN UNSETTLED PATTERN WILL SET UP IN
THE FIRST PART OF THE NEW WEEK. A WEAK LOW PRESSURE AREA COULD
AFFECT THE AREA MONDAY. THEN A MORE SIGNIFICANT STORM IS EXPECTED
MOVE INTO THE REGION FOR CHRISTMAS EVE...FOLLOWED BY STRONG WINDS
AND SCATTERED SNOW SHOWERS FOR CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
MAIN FCST ISSUE THIS MORNING WILL BE THE LIKELIHOOD OF VERY LGT
WINTRY PRECIP OVR THE W MTNS...THE RESULT OF OROGRAPHIC FORCING
AND SHALLOW LYR OF MOISTURE. LATEST MDL DATA SHOWS A PLUME OF
HIGHER LOW LVL MOISTURE IN ASSOC WITH SFC TROUGH ALONG THE PA/NY
BORDER. SFC OBS INDICATE PTYPES OF BOTH -SHSN AND -FZDZ IN THE
REGION AND MDL SOUNDINGS INDICATE BORDERLINE TEMPS AT CLOUD TOP
OF ARND -10C...SO WILL CONTINUE TO FCST SCT -SHSN AND PATCHY -FZDZ
OVR THE W MTNS THIS AM. ADVISORY WAS COLLABORATED WITH ADJ
OFFICES OVR THE N MTNS...WHERE MDLS INDICATE A GREATER LIKELIHOOD
OF MEASURABLE FZDZ. HOWEVER...SOME FZDZ IS ALSO POSSIBLE FURTHER
SOUTH OVR THE LAUREL HIGHLANDS.

ELSEWHERE...WEAK CAA AND PERSISTENT STRATO CU SHOULD TRANSLATE TO
SLOWLY FALLING TEMPS EARLY THIS AM WITH LOWS IN THE 20S OVER MUCH
OF CENTRAL PA AND THE L30S IN THE SUSQ VALLEY.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SATURDAY/...
SFC TROUGH AND RIBBON OF HIGHER LOW LVL MOISTURE WILL SLIDE SOUTH
ACROSS THE REGION LATER TODAY. OROGRAPHIC LIFTING OF THIS SHALLOW
MOIST LYR MAY CONTINUE TO PRODUCE A BIT OF -SHSN/-FZDZ ACROSS THE
LAUREL HIGHLANDS THRU EARLY AFTN. OTHERWISE...ARRIVAL OF DRIER
AIR IN WAKE OF TROF SHOULD PRODUCE PARTIAL CLEARING...ESP WHERE
WEST WIND DOWNSLOPES THE MTNS ACROSS THE SUSQ VALLEY.

MAX TEMPS SHOULD BE SIMILAR TO THURSDAY...WITH U20S OVR THE
HIGHEST TERRAIN OF THE ALLEGHENIES...TO THE U30S ACROSS THE LOWER
SUSQ VALLEY.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE WILL SHIFT SLOWLY EASTWARD FROM THE GREAT LAKES
INTO NORTHERN NEW ENGLAND BY 12Z MONDAY. RESIDUAL LOW LEVEL
MOISTURE ALONG WITH NRN STREAM SHORTWAVE ENERGY ATTEMPTING TO
UNDERCUT AN UPPER RIDGE/HIGH HEIGHTS MIGRATING OVER SOUTHEASTERN
CANADA SHOULD LIMIT SUN INTERVALS---HOWEVER THE SUN SHOULD AT
LEAST MAKE A BRIEF APPEARANCE THIS WEEKEND. SPLIT FLOW REGIME
ACROSS THE LOWER 48 WILL TRANSITION TO A HIGHLY AMPLIFIED PATTERN
BY EARLY NEXT WEEK ACROSS THE LOWER 48...WITH A DEEP NEGATIVELY
TILTED TROUGH EVOLVING OVER THE EASTERN 1/3RD OF THE CONUS.

THE MODELS SEEM TO BE FORMING A CONSENSUS ON THE PESKY LOW
THAT REFUSES TO BE WELL FORECAST...LIFTING IT SLOWLY FROM FL
PANHANDLE NNEWD JUST OFF THE EAST COAST SUN-MON ALONG A LOW LEVEL
BAROCLINIC ZONE THAT MAY NOT BUDGE PAST THE GULF STREAM AS THE
FLOW ALOFT TURNS SOUTHWESTERLY/PARALLEL TO THE COASTAL FRONT.
INCREASED POPS FOR MONDAY OVER THE SE BASED ON MULTI-MODEL/WPC
BLEND. COMPLEX SFC PATTERN WITH SOME HINTS AT LOW LEVEL CAD ALONG
WITH WAA ALOFT VIA SLY FLOW COULD MAKE FOR A MESSY MIXED PTYPE
TRANSITION.

AN INTENSE TRIPLE POINT SYSTEM DEVELOPING ON DEC 23-24 WILL
LIKELY STEAL THE HEADLINES GIVEN ITS TIMING AND LARGE PORTION OF
REAL ESTATE THAT WILL BE AFFECTED. WHILE THE DETAILS REMAIN
UNCLEAR AT THIS POINT...TEMPERATURES SHOULD BE WARM ENOUGH TO
SUPPORT RAIN ON THE FRONT SIDE OF THE SYSTEM BEFORE BRISK WNW
WINDS DRIVE STRONG CAA EAST OF THE APPALACHIANS. THE TIMING OF THE
COLD/OCCLUDED FRONT WILL BE KEY FOR PRECIPITATION TRANSITION FROM
RAIN TO SNOW SHOWERS. AS THE SYSTEM SPINS UP INTO EASTERN
CANADA...THE STRONG CAA CIRCULATING THROUGH THE GREAT LAKES AND OH
VLY SHOULD LEAD TO LAKE EFFECT/UPSLOPE/WRAP AROUND SNOW SHOWERS
OVER THE WESTERN ALLEGHENIES BY CHRISTMAS DAY. A PERIOD OF STRONG
GUSTY WINDS ARE HIGHLY PROBABLE AS THE DYNAMIC SYSTEM INTENSIFIES
SHIFTING NWWD FROM NEW ENGLAND INTO ONTARIO/QUEBEC.

THE TAKE HOME MESSAGE IS THAT A VOLATILE PERIOD OF WEATHER WILL
IMPACT THE AREA THROUGH CHRISTMAS DAY WITH POTENTIAL WIND...RAIN
AND SNOW IMPACTS ALL ON THE TABLE. STAY TUNED.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
LOW LVL MOISTURE TRAPPED BENEATH INVERSION AND NORTHWEST FLOW
OVER THE EASTERN GLAKS WILL KEEP STRATO CU IN PLACE ACROSS MOST
OF CENTRAL PA THROUGH THE OVERNIGHT. LATEST MDL SOUNDINGS POINT
TOWARD PREDOMINANTLY IFR CIGS/VSBYS AT KBFD AND KJST. THE MODELS
SHOW SOME VARIATION BUT MVFR CIGS AT ALL OTHER TAF SITES EITHER
ARE CURRENTLY OCCURRING OR WILL OCCUR BETWEEN 06Z TO 12Z.

A TROUGH OF LOW PRESSURE WILL PUSH THRU THE REGION OVERNIGHT...
PERHAPS PRODUCING A PERIOD OF STEADIER LGT SNOW AT KBFD AND KJST
BTWN 06Z-12Z FRIDAY WITH VSBYS IN THE 2 TO 4SM RANGE. SKIES WILL
STEADILY IMPROVE AS THE DAY CONTINUES WITH VFR CIGS BY 15Z AT ALL
TAF SITES. EXPECT REDUCING CONDITIONS FRI EVENING AT ONLY BFD AND
POSSIBLY JST.


OUTLOOK...

FRI...EARLY AM -SHSN/REDUCED VSBYS POSS AT KJST.

SAT-SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE.

TUE...LOW CIGS WITH RAIN LIKELY.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR
PAZ004>006-010-011-037.

&&

$$
SYNOPSIS...LA CORTE
NEAR TERM...FITZGERALD
SHORT TERM...DEVOIR/FITZGERALD
LONG TERM...STEINBUGL
AVIATION...CERU/RXR




000
FXUS61 KCTP 190641
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
141 AM EST FRI DEC 19 2014

.SYNOPSIS...
HIGH PRESSURE OVER THE GREAT LAKES WILL SLIDE EAST INTO
PENNSYLVANIA THIS WEEKEND. AN UNSETTLED PATTERN WILL SET UP IN
THE FIRST PART OF THE NEW WEEK. A WEAK LOW PRESSURE AREA COULD
AFFECT THE AREA MONDAY. THEN A MORE SIGNIFICANT STORM IS EXPECTED
MOVE INTO THE REGION FOR CHRISTMAS EVE...FOLLOWED BY STRONG WINDS
AND SCATTERED SNOW SHOWERS FOR CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
MAIN FCST ISSUE THIS MORNING WILL BE THE LIKELIHOOD OF VERY LGT
WINTRY PRECIP OVR THE W MTNS...THE RESULT OF OROGRAPHIC FORCING
AND SHALLOW LYR OF MOISTURE. LATEST MDL DATA SHOWS A PLUME OF
HIGHER LOW LVL MOISTURE IN ASSOC WITH SFC TROUGH ALONG THE PA/NY
BORDER. SFC OBS INDICATE PTYPES OF BOTH -SHSN AND -FZDZ IN THE
REGION AND MDL SOUNDINGS INDICATE BORDERLINE TEMPS AT CLOUD TOP
OF ARND -10C...SO WILL CONTINUE TO FCST SCT -SHSN AND PATCHY -FZDZ
OVR THE W MTNS THIS AM. ADVISORY WAS COLLABORATED WITH ADJ
OFFICES OVR THE N MTNS...WHERE MDLS INDICATE A GREATER LIKELIHOOD
OF MEASURABLE FZDZ. HOWEVER...SOME FZDZ IS ALSO POSSIBLE FURTHER
SOUTH OVR THE LAUREL HIGHLANDS.

ELSEWHERE...WEAK CAA AND PERSISTENT STRATO CU SHOULD TRANSLATE TO
SLOWLY FALLING TEMPS EARLY THIS AM WITH LOWS IN THE 20S OVER MUCH
OF CENTRAL PA AND THE L30S IN THE SUSQ VALLEY.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SATURDAY/...
SFC TROUGH AND RIBBON OF HIGHER LOW LVL MOISTURE WILL SLIDE SOUTH
ACROSS THE REGION LATER TODAY. OROGRAPHIC LIFTING OF THIS SHALLOW
MOIST LYR MAY CONTINUE TO PRODUCE A BIT OF -SHSN/-FZDZ ACROSS THE
LAUREL HIGHLANDS THRU EARLY AFTN. OTHERWISE...ARRIVAL OF DRIER
AIR IN WAKE OF TROF SHOULD PRODUCE PARTIAL CLEARING...ESP WHERE
WEST WIND DOWNSLOPES THE MTNS ACROSS THE SUSQ VALLEY.

MAX TEMPS SHOULD BE SIMILAR TO THURSDAY...WITH U20S OVR THE
HIGHEST TERRAIN OF THE ALLEGHENIES...TO THE U30S ACROSS THE LOWER
SUSQ VALLEY.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE WILL SHIFT SLOWLY EASTWARD FROM THE GREAT LAKES
INTO NORTHERN NEW ENGLAND BY 12Z MONDAY. RESIDUAL LOW LEVEL
MOISTURE ALONG WITH NRN STREAM SHORTWAVE ENERGY ATTEMPTING TO
UNDERCUT AN UPPER RIDGE/HIGH HEIGHTS MIGRATING OVER SOUTHEASTERN
CANADA SHOULD LIMIT SUN INTERVALS---HOWEVER THE SUN SHOULD AT
LEAST MAKE A BRIEF APPEARANCE THIS WEEKEND. SPLIT FLOW REGIME
ACROSS THE LOWER 48 WILL TRANSITION TO A HIGHLY AMPLIFIED PATTERN
BY EARLY NEXT WEEK ACROSS THE LOWER 48...WITH A DEEP NEGATIVELY
TILTED TROUGH EVOLVING OVER THE EASTERN 1/3RD OF THE CONUS.

THE MODELS SEEM TO BE FORMING A CONSENSUS ON THE PESKY LOW
THAT REFUSES TO BE WELL FORECAST...LIFTING IT SLOWLY FROM FL
PANHANDLE NNEWD JUST OFF THE EAST COAST SUN-MON ALONG A LOW LEVEL
BAROCLINIC ZONE THAT MAY NOT BUDGE PAST THE GULF STREAM AS THE
FLOW ALOFT TURNS SOUTHWESTERLY/PARALLEL TO THE COASTAL FRONT.
INCREASED POPS FOR MONDAY OVER THE SE BASED ON MULTI-MODEL/WPC
BLEND. COMPLEX SFC PATTERN WITH SOME HINTS AT LOW LEVEL CAD ALONG
WITH WAA ALOFT VIA SLY FLOW COULD MAKE FOR A MESSY MIXED PTYPE
TRANSITION.

AN INTENSE TRIPLE POINT SYSTEM DEVELOPING ON DEC 23-24 WILL
LIKELY STEAL THE HEADLINES GIVEN ITS TIMING AND LARGE PORTION OF
REAL ESTATE THAT WILL BE AFFECTED. WHILE THE DETAILS REMAIN
UNCLEAR AT THIS POINT...TEMPERATURES SHOULD BE WARM ENOUGH TO
SUPPORT RAIN ON THE FRONT SIDE OF THE SYSTEM BEFORE BRISK WNW
WINDS DRIVE STRONG CAA EAST OF THE APPALACHIANS. THE TIMING OF THE
COLD/OCCLUDED FRONT WILL BE KEY FOR PRECIPITATION TRANSITION FROM
RAIN TO SNOW SHOWERS. AS THE SYSTEM SPINS UP INTO EASTERN
CANADA...THE STRONG CAA CIRCULATING THROUGH THE GREAT LAKES AND OH
VLY SHOULD LEAD TO LAKE EFFECT/UPSLOPE/WRAP AROUND SNOW SHOWERS
OVER THE WESTERN ALLEGHENIES BY CHRISTMAS DAY. A PERIOD OF STRONG
GUSTY WINDS ARE HIGHLY PROBABLE AS THE DYNAMIC SYSTEM INTENSIFIES
SHIFTING NWWD FROM NEW ENGLAND INTO ONTARIO/QUEBEC.

THE TAKE HOME MESSAGE IS THAT A VOLATILE PERIOD OF WEATHER WILL
IMPACT THE AREA THROUGH CHRISTMAS DAY WITH POTENTIAL WIND...RAIN
AND SNOW IMPACTS ALL ON THE TABLE. STAY TUNED.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
LOW LVL MOISTURE TRAPPED BENEATH INVERSION AND NORTHWEST FLOW
OVER THE EASTERN GLAKS WILL KEEP STRATO CU IN PLACE ACROSS MOST
OF CENTRAL PA THROUGH THE OVERNIGHT. LATEST MDL SOUNDINGS POINT
TOWARD PREDOMINANTLY IFR CIGS/VSBYS AT KBFD AND KJST. THE MODELS
SHOW SOME VARIATION BUT MVFR CIGS AT ALL OTHER TAF SITES EITHER
ARE CURRENTLY OCCURRING OR WILL OCCUR BETWEEN 06Z TO 12Z.

A TROUGH OF LOW PRESSURE WILL PUSH THRU THE REGION OVERNIGHT...
PERHAPS PRODUCING A PERIOD OF STEADIER LGT SNOW AT KBFD AND KJST
BTWN 06Z-12Z FRIDAY WITH VSBYS IN THE 2 TO 4SM RANGE. SKIES WILL
STEADILY IMPROVE AS THE DAY CONTINUES WITH VFR CIGS BY 15Z AT ALL
TAF SITES. EXPECT REDUCING CONDITIONS FRI EVENING AT ONLY BFD AND
POSSIBLY JST.


OUTLOOK...

FRI...EARLY AM -SHSN/REDUCED VSBYS POSS AT KJST.

SAT-SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE.

TUE...LOW CIGS WITH RAIN LIKELY.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR
PAZ004>006-010-011-037.

&&

$$
SYNOPSIS...LA CORTE
NEAR TERM...FITZGERALD
SHORT TERM...DEVOIR/FITZGERALD
LONG TERM...STEINBUGL
AVIATION...CERU/RXR



000
FXUS61 KPBZ 190626
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
126 AM EST FRI DEC 19 2014

.SYNOPSIS...
A WEAK DISTURBANCE WILL CROSS THE REGION TONIGHT. BUILDING HIGH
PRESSURE IS EXPECTED THROUGH THE WEEKEND...THOUGH CLOUDS WILL
REMAIN.

&&

.NEAR TERM /THROUGH TODAY/...
CURRENTLY TWO DIFFERENT TYPES OF PRECIPITATION BEING GENERATED
PRODUCED BY TWO DIFFERENT MODES OF GENERATION. LIGHT SNOW SHOWERS
EXIST ACROSS THE SOUTH AND HIGHER ELEVATIONS OF THE SOUTHEAST
PRODUCED BY SEEDER-FEEDER METHODS WITH MOISTURE FROM ABOUT
500MB-600MB SEEDING THE MOISTURE TRAPPED BELOW THE INVERSION AT
850MB. THE 00Z UPPER AIR SOUNDING SAMPLED THIS ENVIRONMENT RATHER
NICELY AND THE HI-RES MODELS HAVE PICKED UP ON THIS...EVEN
GENERATING QPF. AS THE SW TROF AXIS SWINGS THROUGH N TO S THE UPPER
LEVEL MOISTURE MOVES QUICKLY OUT WHILE DRYING UP. THIS SHOULD
EFFECTIVELY SQUASH ANY REMAINING SEEDER-FEEDER GENERATED SNOW
SHOWERS ACROSS OUR SOUTH.

ELSEWHERE...ACROSS THE NORTHERN TIER OF THE CWA THE BL MOISTURE
DEPTH HAS BEEN ENHANCED BY AN INJECTION OF UPSTREAM LAKE MOISTURE
THAT HAS RAISED INVERSION HEIGHTS. LAST NIGHT MODELS WERE INDICATING
A BL TOP TEMP IN THE -10C TO -11C RANGE WHICH WOULD BE COLD ENOUGH
TO PRODUCE ICE CRYSTALS AND GENERATE LIGHT SNOW. THE 00Z SOUNDING
VERIFIED THIS OCCURRENCE WITH 850MB TEMPS RIGHT AT -10C...WHICH WOULD
LEAD ONE TO BELIEVE THAT SNOW WOULD RESULT. HOWEVER...LOOKING AT RAP
BUFR SOUNDINGS...THE -10C ISOTHERM LAYER IS RATHER SMALL SPATIALLY
AT 850MB AND THE SAMPLE TAKE SEEMS MORE LIKE THE EXCEPTION THAN THE
RULE. IN ACTUALITY THE BL TOP TEMP IS CLOSER TO -8C WHICH KEEPS
SUPERCOOLED LIQUID INTO PLAY...THUS THE REPORTS OF FZDZ MIXING IN
WITH LIGHT SNOW. AN ADVISORY IS OUT FOR THE AREA DIRECTLY IMPACTED
BY THE FZDZ...AND DEPENDING ON THE DRIFT OF THE DOWN-LAKE
MOISTURE...AN EXPANSION SOUTHWARD MAY BE NECESSARY.

HI-RES MODELS INDICATING A FEED OF ENHANCED LLVL MOISTURE WILL SAG
SOUTHWARD THROUGH THE EARLY MORNING HOURS...REACHING THE PITTSBURGH
METRO AREA NEAR SUNRISE. THIS IS IN RESPONSE TO THE MI-LEVEL TROF
AXIS AND ATTENDANT MID-LEVEL DEFORMATION ZONE. AS IT CONTINUES IT
TREK SOUTH OF LAKE ERIE...THE MOISTURE BEGINS TO ERODE ALONG WITH
THE DEFORMATION ZONE GETTING WASHED OUT. ATTM...HAVE INCLUDED LIGHT
SNOW SHOWERS INTO THE METRO AND AREAS NW TO SE SURROUNDING. WILL SHY
AWAY FROM FZDZ MENTION FOR NOW...AS CONFIDENCE IS NOT HIGH IN THE
POTENTIAL FURTHER SOUTH. CLOUDS WILL CONTINUE TO PLAGUE THE CWA FOR
YET ANOTHER DAY.
TAX

&&

.SHORT TERM /TONIGHT THROUGH SUNDAY/...
SFC HIGH PRES IS PROGGED TO BLD IN UNDER UPR TROFG OVR THE GT LKS
FRI...ENDING ANY LINGERING MRNG SNW SHWRS. THE SFC HIGH IS EXPD TO
BRING DRY WEA THRU THE WKEND...THOUGH PERSISTENT MSTR BLO AN
INVERSION MAY KEEP SKIES MCLDY. A SHRTWV MOVG ACRS THE SERN CONUS
LT SAT/SAT NGT IS NOW PROGGED TO STAY FAR ENOUGH S TO REMOVE ALL
PCPN FM THE FCST FOR AREAS S OF PIT. A WK SHRTWV IS PROGGED FOR
ERLY SUN ACRS THE GT LKS...BUT WITH A LACK OF DEEP MSTR AND THE
SFC HIGH OVERHEAD KEPT THE FCST DRY.

SLGTLY BLO AVG TEMPS SHOULD RTN TO NR SEASONAL LVLS BY SUN.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
WHILE THE MODELS AGREE ON A DEEPENING UPPER LEVEL TROUGH TO CLOSE
OFF OVER THE GREAT LAKES THROUGH THE PERIOD THE DETAILS OF HOW
THIS EXACTLY UNFOLDS WILL BE CRITICAL. BY MONDAY SOUTHERN STREAM
SHORTWAVE AHEAD OF MAIN NORTHERN STREAM UPPER TROUGH DIGGING INTO
THE NORTHERN PLAINS WILL PRODUCE LOW PRESSURE ACROSS THE CAROLINAS
MOVING OFF SHORE OF THE EAST COAST. THE SOUTHEAST RIDGES MAY BE
BRUSHED BY LIGHT RAIN FROM THIS SYSTEM. NEXT UP IS DEEPENING LOW
PRESSURE OVER THE OHIO VALLEY AHEAD OF SHARPLY DIGGING UPPER
TROUGH AND CLOSED LOW MOVING INTO THE WESTERN GREAT LAKES. UPPER
OHIO VALLEY LOOKS TO BE ON THE WARM SIDE OF THE SYSTEM TUESDAY
INTO WEDNESDAY WITH RAIN...FOLLOWED BY STRONG COLD FRONT AND COLD
ADVECTION LATER WEDNESDAY NIGHT AND THURSDAY WITH SNOW SHOWERS.
WITH SUCH A STRONG SYSTEM ALOFT AND FAST DEEPENING LOW PRESSURE AT
THE SURFACE TIMING OF COLD AIR AND EXACT TRACK WILL LIKELY CHANGE
AS WE GET CLOSER TO CHRISTMAS. ALL IN ALL PREVIOUS FORECAST IS
LITTLE CHANGED WITH ONLY MINOR ADJUSTMENTS BASED ON NEWEST WPC
EXTENDED PROGS.

&&

.AVIATION /07Z FRIDAY THROUGH TUESDAY/...
MVFR CIGS EXPECTED OVERNIGHT WITH SITES ALONG AND NORTH OF
INTERSTATE 80 POTENTIALLY SEEING IFR CIGS DEVELOP DURING PERIODS
OF LIGHT SNOW. THERE IS A SLIGHT CHANCE THAT LIGHT FREEZING
DRIZZLE MAY OCCUR AND SPREAD FROM NORTH TO SOUTH OVERNIGHT AS
MOISTURE DECREASES ALOFT LEAVING ONLY LOW LEVEL MOISTURE IN PLACE
TRAPPED UNDER THE INVERSION IN TEMPERATURES NOT SUFFICIENTLY COLD
FOR ICE CRYSTALS TO DEVELOP...BUT CONFIDENCE IS NOT HIGH ENOUGH
TO INCLUDE IN TAFS AT THIS TIME. POTENTIAL FOR FREEZING DRIZZLE
WILL LIKELY BE OVER BY MID MORNING AS MOISTURE POOL BECOMES TOO
SHALLOW.


OUTLOOK.../FRIDAY NIGHT THROUGH TUESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...WINTER WEATHER ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
     PAZ007>009-013>016-022.
WV...NONE.

&&

$$







000
FXUS61 KPBZ 190626
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
126 AM EST FRI DEC 19 2014

.SYNOPSIS...
A WEAK DISTURBANCE WILL CROSS THE REGION TONIGHT. BUILDING HIGH
PRESSURE IS EXPECTED THROUGH THE WEEKEND...THOUGH CLOUDS WILL
REMAIN.

&&

.NEAR TERM /THROUGH TODAY/...
CURRENTLY TWO DIFFERENT TYPES OF PRECIPITATION BEING GENERATED
PRODUCED BY TWO DIFFERENT MODES OF GENERATION. LIGHT SNOW SHOWERS
EXIST ACROSS THE SOUTH AND HIGHER ELEVATIONS OF THE SOUTHEAST
PRODUCED BY SEEDER-FEEDER METHODS WITH MOISTURE FROM ABOUT
500MB-600MB SEEDING THE MOISTURE TRAPPED BELOW THE INVERSION AT
850MB. THE 00Z UPPER AIR SOUNDING SAMPLED THIS ENVIRONMENT RATHER
NICELY AND THE HI-RES MODELS HAVE PICKED UP ON THIS...EVEN
GENERATING QPF. AS THE SW TROF AXIS SWINGS THROUGH N TO S THE UPPER
LEVEL MOISTURE MOVES QUICKLY OUT WHILE DRYING UP. THIS SHOULD
EFFECTIVELY SQUASH ANY REMAINING SEEDER-FEEDER GENERATED SNOW
SHOWERS ACROSS OUR SOUTH.

ELSEWHERE...ACROSS THE NORTHERN TIER OF THE CWA THE BL MOISTURE
DEPTH HAS BEEN ENHANCED BY AN INJECTION OF UPSTREAM LAKE MOISTURE
THAT HAS RAISED INVERSION HEIGHTS. LAST NIGHT MODELS WERE INDICATING
A BL TOP TEMP IN THE -10C TO -11C RANGE WHICH WOULD BE COLD ENOUGH
TO PRODUCE ICE CRYSTALS AND GENERATE LIGHT SNOW. THE 00Z SOUNDING
VERIFIED THIS OCCURRENCE WITH 850MB TEMPS RIGHT AT -10C...WHICH WOULD
LEAD ONE TO BELIEVE THAT SNOW WOULD RESULT. HOWEVER...LOOKING AT RAP
BUFR SOUNDINGS...THE -10C ISOTHERM LAYER IS RATHER SMALL SPATIALLY
AT 850MB AND THE SAMPLE TAKE SEEMS MORE LIKE THE EXCEPTION THAN THE
RULE. IN ACTUALITY THE BL TOP TEMP IS CLOSER TO -8C WHICH KEEPS
SUPERCOOLED LIQUID INTO PLAY...THUS THE REPORTS OF FZDZ MIXING IN
WITH LIGHT SNOW. AN ADVISORY IS OUT FOR THE AREA DIRECTLY IMPACTED
BY THE FZDZ...AND DEPENDING ON THE DRIFT OF THE DOWN-LAKE
MOISTURE...AN EXPANSION SOUTHWARD MAY BE NECESSARY.

HI-RES MODELS INDICATING A FEED OF ENHANCED LLVL MOISTURE WILL SAG
SOUTHWARD THROUGH THE EARLY MORNING HOURS...REACHING THE PITTSBURGH
METRO AREA NEAR SUNRISE. THIS IS IN RESPONSE TO THE MI-LEVEL TROF
AXIS AND ATTENDANT MID-LEVEL DEFORMATION ZONE. AS IT CONTINUES IT
TREK SOUTH OF LAKE ERIE...THE MOISTURE BEGINS TO ERODE ALONG WITH
THE DEFORMATION ZONE GETTING WASHED OUT. ATTM...HAVE INCLUDED LIGHT
SNOW SHOWERS INTO THE METRO AND AREAS NW TO SE SURROUNDING. WILL SHY
AWAY FROM FZDZ MENTION FOR NOW...AS CONFIDENCE IS NOT HIGH IN THE
POTENTIAL FURTHER SOUTH. CLOUDS WILL CONTINUE TO PLAGUE THE CWA FOR
YET ANOTHER DAY.
TAX

&&

.SHORT TERM /TONIGHT THROUGH SUNDAY/...
SFC HIGH PRES IS PROGGED TO BLD IN UNDER UPR TROFG OVR THE GT LKS
FRI...ENDING ANY LINGERING MRNG SNW SHWRS. THE SFC HIGH IS EXPD TO
BRING DRY WEA THRU THE WKEND...THOUGH PERSISTENT MSTR BLO AN
INVERSION MAY KEEP SKIES MCLDY. A SHRTWV MOVG ACRS THE SERN CONUS
LT SAT/SAT NGT IS NOW PROGGED TO STAY FAR ENOUGH S TO REMOVE ALL
PCPN FM THE FCST FOR AREAS S OF PIT. A WK SHRTWV IS PROGGED FOR
ERLY SUN ACRS THE GT LKS...BUT WITH A LACK OF DEEP MSTR AND THE
SFC HIGH OVERHEAD KEPT THE FCST DRY.

SLGTLY BLO AVG TEMPS SHOULD RTN TO NR SEASONAL LVLS BY SUN.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
WHILE THE MODELS AGREE ON A DEEPENING UPPER LEVEL TROUGH TO CLOSE
OFF OVER THE GREAT LAKES THROUGH THE PERIOD THE DETAILS OF HOW
THIS EXACTLY UNFOLDS WILL BE CRITICAL. BY MONDAY SOUTHERN STREAM
SHORTWAVE AHEAD OF MAIN NORTHERN STREAM UPPER TROUGH DIGGING INTO
THE NORTHERN PLAINS WILL PRODUCE LOW PRESSURE ACROSS THE CAROLINAS
MOVING OFF SHORE OF THE EAST COAST. THE SOUTHEAST RIDGES MAY BE
BRUSHED BY LIGHT RAIN FROM THIS SYSTEM. NEXT UP IS DEEPENING LOW
PRESSURE OVER THE OHIO VALLEY AHEAD OF SHARPLY DIGGING UPPER
TROUGH AND CLOSED LOW MOVING INTO THE WESTERN GREAT LAKES. UPPER
OHIO VALLEY LOOKS TO BE ON THE WARM SIDE OF THE SYSTEM TUESDAY
INTO WEDNESDAY WITH RAIN...FOLLOWED BY STRONG COLD FRONT AND COLD
ADVECTION LATER WEDNESDAY NIGHT AND THURSDAY WITH SNOW SHOWERS.
WITH SUCH A STRONG SYSTEM ALOFT AND FAST DEEPENING LOW PRESSURE AT
THE SURFACE TIMING OF COLD AIR AND EXACT TRACK WILL LIKELY CHANGE
AS WE GET CLOSER TO CHRISTMAS. ALL IN ALL PREVIOUS FORECAST IS
LITTLE CHANGED WITH ONLY MINOR ADJUSTMENTS BASED ON NEWEST WPC
EXTENDED PROGS.

&&

.AVIATION /07Z FRIDAY THROUGH TUESDAY/...
MVFR CIGS EXPECTED OVERNIGHT WITH SITES ALONG AND NORTH OF
INTERSTATE 80 POTENTIALLY SEEING IFR CIGS DEVELOP DURING PERIODS
OF LIGHT SNOW. THERE IS A SLIGHT CHANCE THAT LIGHT FREEZING
DRIZZLE MAY OCCUR AND SPREAD FROM NORTH TO SOUTH OVERNIGHT AS
MOISTURE DECREASES ALOFT LEAVING ONLY LOW LEVEL MOISTURE IN PLACE
TRAPPED UNDER THE INVERSION IN TEMPERATURES NOT SUFFICIENTLY COLD
FOR ICE CRYSTALS TO DEVELOP...BUT CONFIDENCE IS NOT HIGH ENOUGH
TO INCLUDE IN TAFS AT THIS TIME. POTENTIAL FOR FREEZING DRIZZLE
WILL LIKELY BE OVER BY MID MORNING AS MOISTURE POOL BECOMES TOO
SHALLOW.


OUTLOOK.../FRIDAY NIGHT THROUGH TUESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...WINTER WEATHER ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
     PAZ007>009-013>016-022.
WV...NONE.

&&

$$






000
FXUS61 KCTP 190612
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
112 AM EST FRI DEC 19 2014

.SYNOPSIS...
COLD NORTHWEST WINDS WILL KEEP FLURRIES AND SCATTERED LIGHT SNOW
SHOWERS OVER THE NORTH AND WEST INTO FRIDAY MORNING. HIGH
PRESSURE WILL SLIDE DOWN FROM THE UPPER GREAT LAKES AND PROVIDE A
GENERALLY FAIR PERIOD FOR MOST OF THE WEEKEND.

AN UNSETTLED PATTERN WILL SET UP IN THE FIRST PART OF THE NEW
WEEK. A WEAK LOW PRESSURE AREA COULD AFFECT THE AREA MONDAY. THEN
A MORE SIGNIFICANT STORM IS EXPECTED MOVE INTO THE REGION FOR
CHRISTMAS EVE...FOLLOWED BY STRONG WINDS AND SCATTERED SNOW
SHOWERS FOR CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AFTER COORDINATING WITH SURROUNDING OFFICES..HAVE OPTED FOR AN
ADVISORY FOR FREEZING DRIZZLE OVER MY NORTHERN COUNTIES. STILL NOT
EXPECTING MUCH...BUT TRAVEL COULD BE IMPACTED SO WE HAVE THE
HEADLINE OUT THROUGH 7 AM.

NO OTHER CHANGES MADE TO THE NEAR TERM FORECAST.

HAVE TINKERED WITH THE NEAR TERM POPS AS MAINLY LIGHT SNOW
SHOWERS OR FLURRIES SEEM THE MOST LIKELY OUTCOME THIS EVENING AND
OVERNIGHT FOR MUCH OF MY WESTERN AND NORTHERN FORECAST AREA. WEST
FACING SLOPES OF THE WEST CENTRAL MOUNTAINS AND LAUREL HIGHLANDS
MAY SEE A LOCALIZED COATING OF SNOW LATE TONIGHT INTO FRI MORNING.

OTHERWISE EXPECT WIDESPREAD STRATUS TO PERSIST ACROSS MOST OF
CENTRAL PA. THE SOUTHEAST WILL LIKELY SEE SOME DISSIPATION BY
FRIDAY MORNING. SURFACE HIGH CENTERED OVER THE NORTHERN GREAT
LAKES AND EASTERN QUEBEC WILL KEEP NORTH/NORTHWEST BOUNDARY LAYER
FLOW GOING THROUGH FRI MORNING...TRANSLATING TO SFC WINDS IN THE 7
TO 11 MPH RANGE.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SATURDAY/...
UPPER FORCING SLIDES EAST OF THE REGION EARLY FRIDAY MORNING...
WITH EXPANSIVE SURFACE HIGH PRESSURE BUILDING OVER THE AREA IN THE
AFTERNOON. THUS...THE AMOUNT/COVERAGE OF THE SNOW SHOWERS AND
FLURRIES SHOULD DIMINISH COMPLETELY ON FRIDAY. MINS WILL STAY A
LITTLE MILDER THAN CLIMO WITH CLOUDS AROUND. MAXES ON FRIDAY VERY
SIMILAR TO TODAY...WITH 30S FOR THE MOUNTAINS AND NEAR 40 IN THE
LOW LANDS WITH THE HELP OF SOME DOWNSLOPE WARMING.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE WILL SHIFT SLOWLY EASTWARD FROM THE GREAT LAKES
INTO NORTHERN NEW ENGLAND BY 12Z MONDAY. RESIDUAL LOW LEVEL
MOISTURE ALONG WITH NRN STREAM SHORTWAVE ENERGY ATTEMPTING TO
UNDERCUT AN UPPER RIDGE/HIGH HEIGHTS MIGRATING OVER SOUTHEASTERN
CANADA SHOULD LIMIT SUN INTERVALS---HOWEVER THE SUN SHOULD AT
LEAST MAKE A BRIEF APPEARANCE THIS WEEKEND. SPLIT FLOW REGIME
ACROSS THE LOWER 48 WILL TRANSITION TO A HIGHLY AMPLIFIED PATTERN
BY EARLY NEXT WEEK ACROSS THE LOWER 48...WITH A DEEP NEGATIVELY
TILTED TROUGH EVOLVING OVER THE EASTERN 1/3RD OF THE CONUS.

THE MODELS SEEM TO BE FORMING A CONSENSUS ON THE PESKY LOW
THAT REFUSES TO BE WELL FORECAST...LIFTING IT SLOWLY FROM FL
PANHANDLE NNEWD JUST OFF THE EAST COAST SUN-MON ALONG A LOW LEVEL
BAROCLINIC ZONE THAT MAY NOT BUDGE PAST THE GULF STREAM AS THE
FLOW ALOFT TURNS SOUTHWESTERLY/PARALLEL TO THE COASTAL FRONT.
INCREASED POPS FOR MONDAY OVER THE SE BASED ON MULTI-MODEL/WPC
BLEND. COMPLEX SFC PATTERN WITH SOME HINTS AT LOW LEVEL CAD ALONG
WITH WAA ALOFT VIA SLY FLOW COULD MAKE FOR A MESSY MIXED PTYPE
TRANSITION.

AN INTENSE TRIPLE POINT SYSTEM DEVELOPING ON DEC 23-24 WILL
LIKELY STEAL THE HEADLINES GIVEN ITS TIMING AND LARGE PORTION OF
REAL ESTATE THAT WILL BE AFFECTED. WHILE THE DETAILS REMAIN
UNCLEAR AT THIS POINT...TEMPERATURES SHOULD BE WARM ENOUGH TO
SUPPORT RAIN ON THE FRONT SIDE OF THE SYSTEM BEFORE BRISK WNW
WINDS DRIVE STRONG CAA EAST OF THE APPALACHIANS. THE TIMING OF THE
COLD/OCCLUDED FRONT WILL BE KEY FOR PRECIPITATION TRANSITION FROM
RAIN TO SNOW SHOWERS. AS THE SYSTEM SPINS UP INTO EASTERN
CANADA...THE STRONG CAA CIRCULATING THROUGH THE GREAT LAKES AND OH
VLY SHOULD LEAD TO LAKE EFFECT/UPSLOPE/WRAP AROUND SNOW SHOWERS
OVER THE WESTERN ALLEGHENIES BY CHRISTMAS DAY. A PERIOD OF STRONG
GUSTY WINDS ARE HIGHLY PROBABLE AS THE DYNAMIC SYSTEM INTENSIFIES
SHIFTING NWWD FROM NEW ENGLAND INTO ONTARIO/QUEBEC.

THE TAKE HOME MESSAGE IS THAT A VOLATILE PERIOD OF WEATHER WILL
IMPACT THE AREA THROUGH CHRISTMAS DAY WITH POTENTIAL WIND...RAIN
AND SNOW IMPACTS ALL ON THE TABLE. STAY TUNED.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
LOW LVL MOISTURE TRAPPED BENEATH INVERSION AND NORTHWEST FLOW
OVER THE EASTERN GLAKS WILL KEEP STRATO CU IN PLACE ACROSS MOST
OF CENTRAL PA THROUGH THE OVERNIGHT. LATEST MDL SOUNDINGS POINT
TOWARD PREDOMINANTLY IFR CIGS/VSBYS AT KBFD AND KJST. THE MODELS
SHOW SOME VARIATION BUT MVFR CIGS AT ALL OTHER TAF SITES EITHER
ARE CURRENTLY OCCURRING OR WILL OCCUR BETWEEN 06Z TO 12Z.

A TROUGH OF LOW PRESSURE WILL PUSH THRU THE REGION OVERNIGHT...
PERHAPS PRODUCING A PERIOD OF STEADIER LGT SNOW AT KBFD AND KJST
BTWN 06Z-12Z FRIDAY WITH VSBYS IN THE 2 TO 4SM RANGE. SKIES WILL
STEADILY IMPROVE AS THE DAY CONTINUES WITH VFR CIGS BY 15Z AT ALL
TAF SITES. EXPECT REDUCING CONDITIONS FRI EVENING AT ONLY BFD AND
POSSIBLY JST.


OUTLOOK...

FRI...EARLY AM -SHSN/REDUCED VSBYS POSS AT KJST.

SAT-SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE.

TUE...LOW CIGS WITH RAIN LIKELY.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR
PAZ004>006-010-011-037.

&&

$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...DEVOIR
LONG TERM...STEINBUGL
AVIATION...CERU/RXR



000
FXUS61 KCTP 190612
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
112 AM EST FRI DEC 19 2014

.SYNOPSIS...
COLD NORTHWEST WINDS WILL KEEP FLURRIES AND SCATTERED LIGHT SNOW
SHOWERS OVER THE NORTH AND WEST INTO FRIDAY MORNING. HIGH
PRESSURE WILL SLIDE DOWN FROM THE UPPER GREAT LAKES AND PROVIDE A
GENERALLY FAIR PERIOD FOR MOST OF THE WEEKEND.

AN UNSETTLED PATTERN WILL SET UP IN THE FIRST PART OF THE NEW
WEEK. A WEAK LOW PRESSURE AREA COULD AFFECT THE AREA MONDAY. THEN
A MORE SIGNIFICANT STORM IS EXPECTED MOVE INTO THE REGION FOR
CHRISTMAS EVE...FOLLOWED BY STRONG WINDS AND SCATTERED SNOW
SHOWERS FOR CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AFTER COORDINATING WITH SURROUNDING OFFICES..HAVE OPTED FOR AN
ADVISORY FOR FREEZING DRIZZLE OVER MY NORTHERN COUNTIES. STILL NOT
EXPECTING MUCH...BUT TRAVEL COULD BE IMPACTED SO WE HAVE THE
HEADLINE OUT THROUGH 7 AM.

NO OTHER CHANGES MADE TO THE NEAR TERM FORECAST.

HAVE TINKERED WITH THE NEAR TERM POPS AS MAINLY LIGHT SNOW
SHOWERS OR FLURRIES SEEM THE MOST LIKELY OUTCOME THIS EVENING AND
OVERNIGHT FOR MUCH OF MY WESTERN AND NORTHERN FORECAST AREA. WEST
FACING SLOPES OF THE WEST CENTRAL MOUNTAINS AND LAUREL HIGHLANDS
MAY SEE A LOCALIZED COATING OF SNOW LATE TONIGHT INTO FRI MORNING.

OTHERWISE EXPECT WIDESPREAD STRATUS TO PERSIST ACROSS MOST OF
CENTRAL PA. THE SOUTHEAST WILL LIKELY SEE SOME DISSIPATION BY
FRIDAY MORNING. SURFACE HIGH CENTERED OVER THE NORTHERN GREAT
LAKES AND EASTERN QUEBEC WILL KEEP NORTH/NORTHWEST BOUNDARY LAYER
FLOW GOING THROUGH FRI MORNING...TRANSLATING TO SFC WINDS IN THE 7
TO 11 MPH RANGE.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SATURDAY/...
UPPER FORCING SLIDES EAST OF THE REGION EARLY FRIDAY MORNING...
WITH EXPANSIVE SURFACE HIGH PRESSURE BUILDING OVER THE AREA IN THE
AFTERNOON. THUS...THE AMOUNT/COVERAGE OF THE SNOW SHOWERS AND
FLURRIES SHOULD DIMINISH COMPLETELY ON FRIDAY. MINS WILL STAY A
LITTLE MILDER THAN CLIMO WITH CLOUDS AROUND. MAXES ON FRIDAY VERY
SIMILAR TO TODAY...WITH 30S FOR THE MOUNTAINS AND NEAR 40 IN THE
LOW LANDS WITH THE HELP OF SOME DOWNSLOPE WARMING.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE WILL SHIFT SLOWLY EASTWARD FROM THE GREAT LAKES
INTO NORTHERN NEW ENGLAND BY 12Z MONDAY. RESIDUAL LOW LEVEL
MOISTURE ALONG WITH NRN STREAM SHORTWAVE ENERGY ATTEMPTING TO
UNDERCUT AN UPPER RIDGE/HIGH HEIGHTS MIGRATING OVER SOUTHEASTERN
CANADA SHOULD LIMIT SUN INTERVALS---HOWEVER THE SUN SHOULD AT
LEAST MAKE A BRIEF APPEARANCE THIS WEEKEND. SPLIT FLOW REGIME
ACROSS THE LOWER 48 WILL TRANSITION TO A HIGHLY AMPLIFIED PATTERN
BY EARLY NEXT WEEK ACROSS THE LOWER 48...WITH A DEEP NEGATIVELY
TILTED TROUGH EVOLVING OVER THE EASTERN 1/3RD OF THE CONUS.

THE MODELS SEEM TO BE FORMING A CONSENSUS ON THE PESKY LOW
THAT REFUSES TO BE WELL FORECAST...LIFTING IT SLOWLY FROM FL
PANHANDLE NNEWD JUST OFF THE EAST COAST SUN-MON ALONG A LOW LEVEL
BAROCLINIC ZONE THAT MAY NOT BUDGE PAST THE GULF STREAM AS THE
FLOW ALOFT TURNS SOUTHWESTERLY/PARALLEL TO THE COASTAL FRONT.
INCREASED POPS FOR MONDAY OVER THE SE BASED ON MULTI-MODEL/WPC
BLEND. COMPLEX SFC PATTERN WITH SOME HINTS AT LOW LEVEL CAD ALONG
WITH WAA ALOFT VIA SLY FLOW COULD MAKE FOR A MESSY MIXED PTYPE
TRANSITION.

AN INTENSE TRIPLE POINT SYSTEM DEVELOPING ON DEC 23-24 WILL
LIKELY STEAL THE HEADLINES GIVEN ITS TIMING AND LARGE PORTION OF
REAL ESTATE THAT WILL BE AFFECTED. WHILE THE DETAILS REMAIN
UNCLEAR AT THIS POINT...TEMPERATURES SHOULD BE WARM ENOUGH TO
SUPPORT RAIN ON THE FRONT SIDE OF THE SYSTEM BEFORE BRISK WNW
WINDS DRIVE STRONG CAA EAST OF THE APPALACHIANS. THE TIMING OF THE
COLD/OCCLUDED FRONT WILL BE KEY FOR PRECIPITATION TRANSITION FROM
RAIN TO SNOW SHOWERS. AS THE SYSTEM SPINS UP INTO EASTERN
CANADA...THE STRONG CAA CIRCULATING THROUGH THE GREAT LAKES AND OH
VLY SHOULD LEAD TO LAKE EFFECT/UPSLOPE/WRAP AROUND SNOW SHOWERS
OVER THE WESTERN ALLEGHENIES BY CHRISTMAS DAY. A PERIOD OF STRONG
GUSTY WINDS ARE HIGHLY PROBABLE AS THE DYNAMIC SYSTEM INTENSIFIES
SHIFTING NWWD FROM NEW ENGLAND INTO ONTARIO/QUEBEC.

THE TAKE HOME MESSAGE IS THAT A VOLATILE PERIOD OF WEATHER WILL
IMPACT THE AREA THROUGH CHRISTMAS DAY WITH POTENTIAL WIND...RAIN
AND SNOW IMPACTS ALL ON THE TABLE. STAY TUNED.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
LOW LVL MOISTURE TRAPPED BENEATH INVERSION AND NORTHWEST FLOW
OVER THE EASTERN GLAKS WILL KEEP STRATO CU IN PLACE ACROSS MOST
OF CENTRAL PA THROUGH THE OVERNIGHT. LATEST MDL SOUNDINGS POINT
TOWARD PREDOMINANTLY IFR CIGS/VSBYS AT KBFD AND KJST. THE MODELS
SHOW SOME VARIATION BUT MVFR CIGS AT ALL OTHER TAF SITES EITHER
ARE CURRENTLY OCCURRING OR WILL OCCUR BETWEEN 06Z TO 12Z.

A TROUGH OF LOW PRESSURE WILL PUSH THRU THE REGION OVERNIGHT...
PERHAPS PRODUCING A PERIOD OF STEADIER LGT SNOW AT KBFD AND KJST
BTWN 06Z-12Z FRIDAY WITH VSBYS IN THE 2 TO 4SM RANGE. SKIES WILL
STEADILY IMPROVE AS THE DAY CONTINUES WITH VFR CIGS BY 15Z AT ALL
TAF SITES. EXPECT REDUCING CONDITIONS FRI EVENING AT ONLY BFD AND
POSSIBLY JST.


OUTLOOK...

FRI...EARLY AM -SHSN/REDUCED VSBYS POSS AT KJST.

SAT-SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE.

TUE...LOW CIGS WITH RAIN LIKELY.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR
PAZ004>006-010-011-037.

&&

$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...DEVOIR
LONG TERM...STEINBUGL
AVIATION...CERU/RXR



000
FXUS61 KCTP 190612
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
112 AM EST FRI DEC 19 2014

.SYNOPSIS...
COLD NORTHWEST WINDS WILL KEEP FLURRIES AND SCATTERED LIGHT SNOW
SHOWERS OVER THE NORTH AND WEST INTO FRIDAY MORNING. HIGH
PRESSURE WILL SLIDE DOWN FROM THE UPPER GREAT LAKES AND PROVIDE A
GENERALLY FAIR PERIOD FOR MOST OF THE WEEKEND.

AN UNSETTLED PATTERN WILL SET UP IN THE FIRST PART OF THE NEW
WEEK. A WEAK LOW PRESSURE AREA COULD AFFECT THE AREA MONDAY. THEN
A MORE SIGNIFICANT STORM IS EXPECTED MOVE INTO THE REGION FOR
CHRISTMAS EVE...FOLLOWED BY STRONG WINDS AND SCATTERED SNOW
SHOWERS FOR CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AFTER COORDINATING WITH SURROUNDING OFFICES..HAVE OPTED FOR AN
ADVISORY FOR FREEZING DRIZZLE OVER MY NORTHERN COUNTIES. STILL NOT
EXPECTING MUCH...BUT TRAVEL COULD BE IMPACTED SO WE HAVE THE
HEADLINE OUT THROUGH 7 AM.

NO OTHER CHANGES MADE TO THE NEAR TERM FORECAST.

HAVE TINKERED WITH THE NEAR TERM POPS AS MAINLY LIGHT SNOW
SHOWERS OR FLURRIES SEEM THE MOST LIKELY OUTCOME THIS EVENING AND
OVERNIGHT FOR MUCH OF MY WESTERN AND NORTHERN FORECAST AREA. WEST
FACING SLOPES OF THE WEST CENTRAL MOUNTAINS AND LAUREL HIGHLANDS
MAY SEE A LOCALIZED COATING OF SNOW LATE TONIGHT INTO FRI MORNING.

OTHERWISE EXPECT WIDESPREAD STRATUS TO PERSIST ACROSS MOST OF
CENTRAL PA. THE SOUTHEAST WILL LIKELY SEE SOME DISSIPATION BY
FRIDAY MORNING. SURFACE HIGH CENTERED OVER THE NORTHERN GREAT
LAKES AND EASTERN QUEBEC WILL KEEP NORTH/NORTHWEST BOUNDARY LAYER
FLOW GOING THROUGH FRI MORNING...TRANSLATING TO SFC WINDS IN THE 7
TO 11 MPH RANGE.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SATURDAY/...
UPPER FORCING SLIDES EAST OF THE REGION EARLY FRIDAY MORNING...
WITH EXPANSIVE SURFACE HIGH PRESSURE BUILDING OVER THE AREA IN THE
AFTERNOON. THUS...THE AMOUNT/COVERAGE OF THE SNOW SHOWERS AND
FLURRIES SHOULD DIMINISH COMPLETELY ON FRIDAY. MINS WILL STAY A
LITTLE MILDER THAN CLIMO WITH CLOUDS AROUND. MAXES ON FRIDAY VERY
SIMILAR TO TODAY...WITH 30S FOR THE MOUNTAINS AND NEAR 40 IN THE
LOW LANDS WITH THE HELP OF SOME DOWNSLOPE WARMING.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE WILL SHIFT SLOWLY EASTWARD FROM THE GREAT LAKES
INTO NORTHERN NEW ENGLAND BY 12Z MONDAY. RESIDUAL LOW LEVEL
MOISTURE ALONG WITH NRN STREAM SHORTWAVE ENERGY ATTEMPTING TO
UNDERCUT AN UPPER RIDGE/HIGH HEIGHTS MIGRATING OVER SOUTHEASTERN
CANADA SHOULD LIMIT SUN INTERVALS---HOWEVER THE SUN SHOULD AT
LEAST MAKE A BRIEF APPEARANCE THIS WEEKEND. SPLIT FLOW REGIME
ACROSS THE LOWER 48 WILL TRANSITION TO A HIGHLY AMPLIFIED PATTERN
BY EARLY NEXT WEEK ACROSS THE LOWER 48...WITH A DEEP NEGATIVELY
TILTED TROUGH EVOLVING OVER THE EASTERN 1/3RD OF THE CONUS.

THE MODELS SEEM TO BE FORMING A CONSENSUS ON THE PESKY LOW
THAT REFUSES TO BE WELL FORECAST...LIFTING IT SLOWLY FROM FL
PANHANDLE NNEWD JUST OFF THE EAST COAST SUN-MON ALONG A LOW LEVEL
BAROCLINIC ZONE THAT MAY NOT BUDGE PAST THE GULF STREAM AS THE
FLOW ALOFT TURNS SOUTHWESTERLY/PARALLEL TO THE COASTAL FRONT.
INCREASED POPS FOR MONDAY OVER THE SE BASED ON MULTI-MODEL/WPC
BLEND. COMPLEX SFC PATTERN WITH SOME HINTS AT LOW LEVEL CAD ALONG
WITH WAA ALOFT VIA SLY FLOW COULD MAKE FOR A MESSY MIXED PTYPE
TRANSITION.

AN INTENSE TRIPLE POINT SYSTEM DEVELOPING ON DEC 23-24 WILL
LIKELY STEAL THE HEADLINES GIVEN ITS TIMING AND LARGE PORTION OF
REAL ESTATE THAT WILL BE AFFECTED. WHILE THE DETAILS REMAIN
UNCLEAR AT THIS POINT...TEMPERATURES SHOULD BE WARM ENOUGH TO
SUPPORT RAIN ON THE FRONT SIDE OF THE SYSTEM BEFORE BRISK WNW
WINDS DRIVE STRONG CAA EAST OF THE APPALACHIANS. THE TIMING OF THE
COLD/OCCLUDED FRONT WILL BE KEY FOR PRECIPITATION TRANSITION FROM
RAIN TO SNOW SHOWERS. AS THE SYSTEM SPINS UP INTO EASTERN
CANADA...THE STRONG CAA CIRCULATING THROUGH THE GREAT LAKES AND OH
VLY SHOULD LEAD TO LAKE EFFECT/UPSLOPE/WRAP AROUND SNOW SHOWERS
OVER THE WESTERN ALLEGHENIES BY CHRISTMAS DAY. A PERIOD OF STRONG
GUSTY WINDS ARE HIGHLY PROBABLE AS THE DYNAMIC SYSTEM INTENSIFIES
SHIFTING NWWD FROM NEW ENGLAND INTO ONTARIO/QUEBEC.

THE TAKE HOME MESSAGE IS THAT A VOLATILE PERIOD OF WEATHER WILL
IMPACT THE AREA THROUGH CHRISTMAS DAY WITH POTENTIAL WIND...RAIN
AND SNOW IMPACTS ALL ON THE TABLE. STAY TUNED.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
LOW LVL MOISTURE TRAPPED BENEATH INVERSION AND NORTHWEST FLOW
OVER THE EASTERN GLAKS WILL KEEP STRATO CU IN PLACE ACROSS MOST
OF CENTRAL PA THROUGH THE OVERNIGHT. LATEST MDL SOUNDINGS POINT
TOWARD PREDOMINANTLY IFR CIGS/VSBYS AT KBFD AND KJST. THE MODELS
SHOW SOME VARIATION BUT MVFR CIGS AT ALL OTHER TAF SITES EITHER
ARE CURRENTLY OCCURRING OR WILL OCCUR BETWEEN 06Z TO 12Z.

A TROUGH OF LOW PRESSURE WILL PUSH THRU THE REGION OVERNIGHT...
PERHAPS PRODUCING A PERIOD OF STEADIER LGT SNOW AT KBFD AND KJST
BTWN 06Z-12Z FRIDAY WITH VSBYS IN THE 2 TO 4SM RANGE. SKIES WILL
STEADILY IMPROVE AS THE DAY CONTINUES WITH VFR CIGS BY 15Z AT ALL
TAF SITES. EXPECT REDUCING CONDITIONS FRI EVENING AT ONLY BFD AND
POSSIBLY JST.


OUTLOOK...

FRI...EARLY AM -SHSN/REDUCED VSBYS POSS AT KJST.

SAT-SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE.

TUE...LOW CIGS WITH RAIN LIKELY.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR
PAZ004>006-010-011-037.

&&

$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...DEVOIR
LONG TERM...STEINBUGL
AVIATION...CERU/RXR



000
FXUS61 KCTP 190612
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
112 AM EST FRI DEC 19 2014

.SYNOPSIS...
COLD NORTHWEST WINDS WILL KEEP FLURRIES AND SCATTERED LIGHT SNOW
SHOWERS OVER THE NORTH AND WEST INTO FRIDAY MORNING. HIGH
PRESSURE WILL SLIDE DOWN FROM THE UPPER GREAT LAKES AND PROVIDE A
GENERALLY FAIR PERIOD FOR MOST OF THE WEEKEND.

AN UNSETTLED PATTERN WILL SET UP IN THE FIRST PART OF THE NEW
WEEK. A WEAK LOW PRESSURE AREA COULD AFFECT THE AREA MONDAY. THEN
A MORE SIGNIFICANT STORM IS EXPECTED MOVE INTO THE REGION FOR
CHRISTMAS EVE...FOLLOWED BY STRONG WINDS AND SCATTERED SNOW
SHOWERS FOR CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AFTER COORDINATING WITH SURROUNDING OFFICES..HAVE OPTED FOR AN
ADVISORY FOR FREEZING DRIZZLE OVER MY NORTHERN COUNTIES. STILL NOT
EXPECTING MUCH...BUT TRAVEL COULD BE IMPACTED SO WE HAVE THE
HEADLINE OUT THROUGH 7 AM.

NO OTHER CHANGES MADE TO THE NEAR TERM FORECAST.

HAVE TINKERED WITH THE NEAR TERM POPS AS MAINLY LIGHT SNOW
SHOWERS OR FLURRIES SEEM THE MOST LIKELY OUTCOME THIS EVENING AND
OVERNIGHT FOR MUCH OF MY WESTERN AND NORTHERN FORECAST AREA. WEST
FACING SLOPES OF THE WEST CENTRAL MOUNTAINS AND LAUREL HIGHLANDS
MAY SEE A LOCALIZED COATING OF SNOW LATE TONIGHT INTO FRI MORNING.

OTHERWISE EXPECT WIDESPREAD STRATUS TO PERSIST ACROSS MOST OF
CENTRAL PA. THE SOUTHEAST WILL LIKELY SEE SOME DISSIPATION BY
FRIDAY MORNING. SURFACE HIGH CENTERED OVER THE NORTHERN GREAT
LAKES AND EASTERN QUEBEC WILL KEEP NORTH/NORTHWEST BOUNDARY LAYER
FLOW GOING THROUGH FRI MORNING...TRANSLATING TO SFC WINDS IN THE 7
TO 11 MPH RANGE.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SATURDAY/...
UPPER FORCING SLIDES EAST OF THE REGION EARLY FRIDAY MORNING...
WITH EXPANSIVE SURFACE HIGH PRESSURE BUILDING OVER THE AREA IN THE
AFTERNOON. THUS...THE AMOUNT/COVERAGE OF THE SNOW SHOWERS AND
FLURRIES SHOULD DIMINISH COMPLETELY ON FRIDAY. MINS WILL STAY A
LITTLE MILDER THAN CLIMO WITH CLOUDS AROUND. MAXES ON FRIDAY VERY
SIMILAR TO TODAY...WITH 30S FOR THE MOUNTAINS AND NEAR 40 IN THE
LOW LANDS WITH THE HELP OF SOME DOWNSLOPE WARMING.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE WILL SHIFT SLOWLY EASTWARD FROM THE GREAT LAKES
INTO NORTHERN NEW ENGLAND BY 12Z MONDAY. RESIDUAL LOW LEVEL
MOISTURE ALONG WITH NRN STREAM SHORTWAVE ENERGY ATTEMPTING TO
UNDERCUT AN UPPER RIDGE/HIGH HEIGHTS MIGRATING OVER SOUTHEASTERN
CANADA SHOULD LIMIT SUN INTERVALS---HOWEVER THE SUN SHOULD AT
LEAST MAKE A BRIEF APPEARANCE THIS WEEKEND. SPLIT FLOW REGIME
ACROSS THE LOWER 48 WILL TRANSITION TO A HIGHLY AMPLIFIED PATTERN
BY EARLY NEXT WEEK ACROSS THE LOWER 48...WITH A DEEP NEGATIVELY
TILTED TROUGH EVOLVING OVER THE EASTERN 1/3RD OF THE CONUS.

THE MODELS SEEM TO BE FORMING A CONSENSUS ON THE PESKY LOW
THAT REFUSES TO BE WELL FORECAST...LIFTING IT SLOWLY FROM FL
PANHANDLE NNEWD JUST OFF THE EAST COAST SUN-MON ALONG A LOW LEVEL
BAROCLINIC ZONE THAT MAY NOT BUDGE PAST THE GULF STREAM AS THE
FLOW ALOFT TURNS SOUTHWESTERLY/PARALLEL TO THE COASTAL FRONT.
INCREASED POPS FOR MONDAY OVER THE SE BASED ON MULTI-MODEL/WPC
BLEND. COMPLEX SFC PATTERN WITH SOME HINTS AT LOW LEVEL CAD ALONG
WITH WAA ALOFT VIA SLY FLOW COULD MAKE FOR A MESSY MIXED PTYPE
TRANSITION.

AN INTENSE TRIPLE POINT SYSTEM DEVELOPING ON DEC 23-24 WILL
LIKELY STEAL THE HEADLINES GIVEN ITS TIMING AND LARGE PORTION OF
REAL ESTATE THAT WILL BE AFFECTED. WHILE THE DETAILS REMAIN
UNCLEAR AT THIS POINT...TEMPERATURES SHOULD BE WARM ENOUGH TO
SUPPORT RAIN ON THE FRONT SIDE OF THE SYSTEM BEFORE BRISK WNW
WINDS DRIVE STRONG CAA EAST OF THE APPALACHIANS. THE TIMING OF THE
COLD/OCCLUDED FRONT WILL BE KEY FOR PRECIPITATION TRANSITION FROM
RAIN TO SNOW SHOWERS. AS THE SYSTEM SPINS UP INTO EASTERN
CANADA...THE STRONG CAA CIRCULATING THROUGH THE GREAT LAKES AND OH
VLY SHOULD LEAD TO LAKE EFFECT/UPSLOPE/WRAP AROUND SNOW SHOWERS
OVER THE WESTERN ALLEGHENIES BY CHRISTMAS DAY. A PERIOD OF STRONG
GUSTY WINDS ARE HIGHLY PROBABLE AS THE DYNAMIC SYSTEM INTENSIFIES
SHIFTING NWWD FROM NEW ENGLAND INTO ONTARIO/QUEBEC.

THE TAKE HOME MESSAGE IS THAT A VOLATILE PERIOD OF WEATHER WILL
IMPACT THE AREA THROUGH CHRISTMAS DAY WITH POTENTIAL WIND...RAIN
AND SNOW IMPACTS ALL ON THE TABLE. STAY TUNED.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
LOW LVL MOISTURE TRAPPED BENEATH INVERSION AND NORTHWEST FLOW
OVER THE EASTERN GLAKS WILL KEEP STRATO CU IN PLACE ACROSS MOST
OF CENTRAL PA THROUGH THE OVERNIGHT. LATEST MDL SOUNDINGS POINT
TOWARD PREDOMINANTLY IFR CIGS/VSBYS AT KBFD AND KJST. THE MODELS
SHOW SOME VARIATION BUT MVFR CIGS AT ALL OTHER TAF SITES EITHER
ARE CURRENTLY OCCURRING OR WILL OCCUR BETWEEN 06Z TO 12Z.

A TROUGH OF LOW PRESSURE WILL PUSH THRU THE REGION OVERNIGHT...
PERHAPS PRODUCING A PERIOD OF STEADIER LGT SNOW AT KBFD AND KJST
BTWN 06Z-12Z FRIDAY WITH VSBYS IN THE 2 TO 4SM RANGE. SKIES WILL
STEADILY IMPROVE AS THE DAY CONTINUES WITH VFR CIGS BY 15Z AT ALL
TAF SITES. EXPECT REDUCING CONDITIONS FRI EVENING AT ONLY BFD AND
POSSIBLY JST.


OUTLOOK...

FRI...EARLY AM -SHSN/REDUCED VSBYS POSS AT KJST.

SAT-SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE.

TUE...LOW CIGS WITH RAIN LIKELY.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR
PAZ004>006-010-011-037.

&&

$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...DEVOIR
LONG TERM...STEINBUGL
AVIATION...CERU/RXR



000
FXUS61 KPBZ 190603
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
103 AM EST FRI DEC 19 2014

.SYNOPSIS...
A WEAK DISTURBANCE WILL CROSS THE REGION TONIGHT. BUILDING HIGH
PRESSURE IS EXPECTED THROUGH THE WEEKEND...THOUGH CLOUDS WILL
REMAIN.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AN UTTERLY POOR SNOW CRYSTAL GROWTH HABIT EXISTS OVER THE CWA THIS
EVENING...AS EVIDENCED BY THE PINHEAD SIZED SNOWFLAKES/GRAINS THAT
HAVE BEEN SCATTERED ACROSS THE AREA IN THE FORM OF "FLURRIES." IN
ADDITION...AREAS JUST TO THE NORTH AND NORTHWEST OF OUR CWA HAVE
STARTED TO REPORT FREEZING DRIZZLE. THIS SEEMS LIKELY TO CONTINUE
TO FILTER INTO AT LEAST THE NORTHERN REACHES OF THE CWA AS
MOISTURE INCREASES...BUT STILL LITTLE MOISTURE EXISTS ABOVE ABOUT
THE -8C ISOTHERM. AS SUCH...WHILE DEEPER MOISTURE MAY ALLOW SOME
TREND TOWARD SNOW SHOWER ACTIVITY...IT SEEMS INSUFFICIENT TO
PRECLUDE FREEZING DRIZZLE FROM CONTINUING TO DEVELOP IN THE
NORTHERN PORTIONS OF THE CWA.

ADDITIONALLY...WITH AN INCOMING SHORT WAVE TROUGH AND A BIT OF
ELEVATED MOISTURE...SOME SEEDER-FEEDER TYPE OF SNOW FLURRY ACTION
DOES SEEM POSSIBLE FOR A SHORT WINDOW AS THE WAVE TRACKS
THROUGH...HOWEVER MODEL CROSS SECTIONS...TIME HEIGHT
SECTIONS...AND PLAN DEPICTIONS ALL GENERALLY REVEAL A QUICK TREND
TOWARD ZERO MICROBARS/SEC OF LAYER NEGATIVE OMEGA VALUES BETWEEN
00Z AND 06Z THIS EVENING. AS A RESULT...WITH DRY AIR BETWEEN THE
TWO MOIST LAYERS...WEAKENING LIFT ALOFT...AND POOR CRYSTAL GROWTH
BELOW...IT WOULD SEEM JUST A GENERAL EXPANSION IN THE FLURRIES FOR
A FEW HOURS AS THE WAVE TRACKS THROUGH SHOULD BE THE MAIN PROBLEM
FOR THE NIGHT OVER THE REST OF THE CWA. UNFORTUNATELY...ROAD
TEMPERATURES HAVE TRENDED NEAR FREEZING THROUGH THE EVENING...SO
REPORTS OF NUMEROUS ACCIDENTS HAVE COME IN ACROSS THE I-70 AND
SOUTH CORRIDOR AS LIGHT SNOW INITIALLY MELTED THEN REFROZE ON
ROADWAYS. LUCKILY ENOUGH...THIS WAVE IS TRACKING THROUGH RATHER
QUICKLY...AND AFTER ITS PASSAGE...EVEN BOUNDARY LAYER RH VALUES
START TO FALL OFF A BIT...SO IT WOULD SEEM EVEN THE POOR GROWTH
HABIT MAY DETERIORATE BY MORNING. FRIES

&&

.SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY/...
SFC HIGH PRES IS PROGGED TO BLD IN UNDER UPR TROFG OVR THE GT LKS
FRI...ENDING ANY LINGERING MRNG SNW SHWRS. THE SFC HIGH IS EXPD TO
BRING DRY WEA THRU THE WKEND...THOUGH PERSISTENT MSTR BLO AN
INVERSION MAY KEEP SKIES MCLDY. A SHRTWV MOVG ACRS THE SERN CONUS
LT SAT/SAT NGT IS NOW PROGGED TO STAY FAR ENOUGH S TO REMOVE ALL
PCPN FM THE FCST FOR AREAS S OF PIT. A WK SHRTWV IS PROGGED FOR
ERLY SUN ACRS THE GT LKS...BUT WITH A LACK OF DEEP MSTR AND THE
SFC HIGH OVERHEAD KEPT THE FCST DRY.

SLGTLY BLO AVG TEMPS SHOULD RTN TO NR SEASONAL LVLS BY SUN.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
WHILE THE MODELS AGREE ON A DEEPENING UPPER LEVEL TROUGH TO CLOSE
OFF OVER THE GREAT LAKES THROUGH THE PERIOD THE DETAILS OF HOW
THIS EXACTLY UNFOLDS WILL BE CRITICAL. BY MONDAY SOUTHERN STREAM
SHORTWAVE AHEAD OF MAIN NORTHERN STREAM UPPER TROUGH DIGGING INTO
THE NORTHERN PLAINS WILL PRODUCE LOW PRESSURE ACROSS THE CAROLINAS
MOVING OFF SHORE OF THE EAST COAST. THE SOUTHEAST RIDGES MAY BE
BRUSHED BY LIGHT RAIN FROM THIS SYSTEM. NEXT UP IS DEEPENING LOW
PRESSURE OVER THE OHIO VALLEY AHEAD OF SHARPLY DIGGING UPPER
TROUGH AND CLOSED LOW MOVING INTO THE WESTERN GREAT LAKES. UPPER
OHIO VALLEY LOOKS TO BE ON THE WARM SIDE OF THE SYSTEM TUESDAY
INTO WEDNESDAY WITH RAIN...FOLLOWED BY STRONG COLD FRONT AND COLD
ADVECTION LATER WEDNESDAY NIGHT AND THURSDAY WITH SNOW SHOWERS.
WITH SUCH A STRONG SYSTEM ALOFT AND FAST DEEPENING LOW PRESSURE AT
THE SURFACE TIMING OF COLD AIR AND EXACT TRACK WILL LIKELY CHANGE
AS WE GET CLOSER TO CHRISTMAS. ALL IN ALL PREVIOUS FORECAST IS
LITTLE CHANGED WITH ONLY MINOR ADJUSTMENTS BASED ON NEWEST WPC
EXTENDED PROGS.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
MVFR CIGS EXPECTED OVERNIGHT WITH SITES ALONG AND NORTH OF
INTERSTATE 80 POTENTIALLY SEEING IFR CIGS DEVELOP DURING PERIODS
OF LIGHT SNOW. THERE IS A SLIGHT CHANCE THAT LIGHT FREEZING
DRIZZLE MAY OCCUR AND SPREAD FROM NORTH TO SOUTH OVERNIGHT AS
MOISTURE DECREASES ALOFT LEAVING ONLY LOW LEVEL MOISTURE IN PLACE
TRAPPED UNDER THE INVERSION IN TEMPERATURES NOT SUFFICIENTLY COLD
FOR ICE CRYSTALS TO DEVELOP...BUT CONFIDENCE IS NOT HIGH ENOUGH
TO INCLUDE IN TAFS AT THIS TIME. POTENTIAL FOR FREEZING DRIZZLE
WILL LIKELY BE OVER BY MID MORNING AS MOISTURE POOL BECOMES TOO
SHALLOW.


OUTLOOK.../FRIDAY NIGHT THROUGH TUESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...WINTER WEATHER ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
     PAZ007>009-013>016-022.
WV...NONE.

&&

$$






000
FXUS61 KPBZ 190603
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
103 AM EST FRI DEC 19 2014

.SYNOPSIS...
A WEAK DISTURBANCE WILL CROSS THE REGION TONIGHT. BUILDING HIGH
PRESSURE IS EXPECTED THROUGH THE WEEKEND...THOUGH CLOUDS WILL
REMAIN.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AN UTTERLY POOR SNOW CRYSTAL GROWTH HABIT EXISTS OVER THE CWA THIS
EVENING...AS EVIDENCED BY THE PINHEAD SIZED SNOWFLAKES/GRAINS THAT
HAVE BEEN SCATTERED ACROSS THE AREA IN THE FORM OF "FLURRIES." IN
ADDITION...AREAS JUST TO THE NORTH AND NORTHWEST OF OUR CWA HAVE
STARTED TO REPORT FREEZING DRIZZLE. THIS SEEMS LIKELY TO CONTINUE
TO FILTER INTO AT LEAST THE NORTHERN REACHES OF THE CWA AS
MOISTURE INCREASES...BUT STILL LITTLE MOISTURE EXISTS ABOVE ABOUT
THE -8C ISOTHERM. AS SUCH...WHILE DEEPER MOISTURE MAY ALLOW SOME
TREND TOWARD SNOW SHOWER ACTIVITY...IT SEEMS INSUFFICIENT TO
PRECLUDE FREEZING DRIZZLE FROM CONTINUING TO DEVELOP IN THE
NORTHERN PORTIONS OF THE CWA.

ADDITIONALLY...WITH AN INCOMING SHORT WAVE TROUGH AND A BIT OF
ELEVATED MOISTURE...SOME SEEDER-FEEDER TYPE OF SNOW FLURRY ACTION
DOES SEEM POSSIBLE FOR A SHORT WINDOW AS THE WAVE TRACKS
THROUGH...HOWEVER MODEL CROSS SECTIONS...TIME HEIGHT
SECTIONS...AND PLAN DEPICTIONS ALL GENERALLY REVEAL A QUICK TREND
TOWARD ZERO MICROBARS/SEC OF LAYER NEGATIVE OMEGA VALUES BETWEEN
00Z AND 06Z THIS EVENING. AS A RESULT...WITH DRY AIR BETWEEN THE
TWO MOIST LAYERS...WEAKENING LIFT ALOFT...AND POOR CRYSTAL GROWTH
BELOW...IT WOULD SEEM JUST A GENERAL EXPANSION IN THE FLURRIES FOR
A FEW HOURS AS THE WAVE TRACKS THROUGH SHOULD BE THE MAIN PROBLEM
FOR THE NIGHT OVER THE REST OF THE CWA. UNFORTUNATELY...ROAD
TEMPERATURES HAVE TRENDED NEAR FREEZING THROUGH THE EVENING...SO
REPORTS OF NUMEROUS ACCIDENTS HAVE COME IN ACROSS THE I-70 AND
SOUTH CORRIDOR AS LIGHT SNOW INITIALLY MELTED THEN REFROZE ON
ROADWAYS. LUCKILY ENOUGH...THIS WAVE IS TRACKING THROUGH RATHER
QUICKLY...AND AFTER ITS PASSAGE...EVEN BOUNDARY LAYER RH VALUES
START TO FALL OFF A BIT...SO IT WOULD SEEM EVEN THE POOR GROWTH
HABIT MAY DETERIORATE BY MORNING. FRIES

&&

.SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY/...
SFC HIGH PRES IS PROGGED TO BLD IN UNDER UPR TROFG OVR THE GT LKS
FRI...ENDING ANY LINGERING MRNG SNW SHWRS. THE SFC HIGH IS EXPD TO
BRING DRY WEA THRU THE WKEND...THOUGH PERSISTENT MSTR BLO AN
INVERSION MAY KEEP SKIES MCLDY. A SHRTWV MOVG ACRS THE SERN CONUS
LT SAT/SAT NGT IS NOW PROGGED TO STAY FAR ENOUGH S TO REMOVE ALL
PCPN FM THE FCST FOR AREAS S OF PIT. A WK SHRTWV IS PROGGED FOR
ERLY SUN ACRS THE GT LKS...BUT WITH A LACK OF DEEP MSTR AND THE
SFC HIGH OVERHEAD KEPT THE FCST DRY.

SLGTLY BLO AVG TEMPS SHOULD RTN TO NR SEASONAL LVLS BY SUN.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
WHILE THE MODELS AGREE ON A DEEPENING UPPER LEVEL TROUGH TO CLOSE
OFF OVER THE GREAT LAKES THROUGH THE PERIOD THE DETAILS OF HOW
THIS EXACTLY UNFOLDS WILL BE CRITICAL. BY MONDAY SOUTHERN STREAM
SHORTWAVE AHEAD OF MAIN NORTHERN STREAM UPPER TROUGH DIGGING INTO
THE NORTHERN PLAINS WILL PRODUCE LOW PRESSURE ACROSS THE CAROLINAS
MOVING OFF SHORE OF THE EAST COAST. THE SOUTHEAST RIDGES MAY BE
BRUSHED BY LIGHT RAIN FROM THIS SYSTEM. NEXT UP IS DEEPENING LOW
PRESSURE OVER THE OHIO VALLEY AHEAD OF SHARPLY DIGGING UPPER
TROUGH AND CLOSED LOW MOVING INTO THE WESTERN GREAT LAKES. UPPER
OHIO VALLEY LOOKS TO BE ON THE WARM SIDE OF THE SYSTEM TUESDAY
INTO WEDNESDAY WITH RAIN...FOLLOWED BY STRONG COLD FRONT AND COLD
ADVECTION LATER WEDNESDAY NIGHT AND THURSDAY WITH SNOW SHOWERS.
WITH SUCH A STRONG SYSTEM ALOFT AND FAST DEEPENING LOW PRESSURE AT
THE SURFACE TIMING OF COLD AIR AND EXACT TRACK WILL LIKELY CHANGE
AS WE GET CLOSER TO CHRISTMAS. ALL IN ALL PREVIOUS FORECAST IS
LITTLE CHANGED WITH ONLY MINOR ADJUSTMENTS BASED ON NEWEST WPC
EXTENDED PROGS.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
MVFR CIGS EXPECTED OVERNIGHT WITH SITES ALONG AND NORTH OF
INTERSTATE 80 POTENTIALLY SEEING IFR CIGS DEVELOP DURING PERIODS
OF LIGHT SNOW. THERE IS A SLIGHT CHANCE THAT LIGHT FREEZING
DRIZZLE MAY OCCUR AND SPREAD FROM NORTH TO SOUTH OVERNIGHT AS
MOISTURE DECREASES ALOFT LEAVING ONLY LOW LEVEL MOISTURE IN PLACE
TRAPPED UNDER THE INVERSION IN TEMPERATURES NOT SUFFICIENTLY COLD
FOR ICE CRYSTALS TO DEVELOP...BUT CONFIDENCE IS NOT HIGH ENOUGH
TO INCLUDE IN TAFS AT THIS TIME. POTENTIAL FOR FREEZING DRIZZLE
WILL LIKELY BE OVER BY MID MORNING AS MOISTURE POOL BECOMES TOO
SHALLOW.


OUTLOOK.../FRIDAY NIGHT THROUGH TUESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...WINTER WEATHER ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
     PAZ007>009-013>016-022.
WV...NONE.

&&

$$






000
FXUS61 KPBZ 190603
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
103 AM EST FRI DEC 19 2014

.SYNOPSIS...
A WEAK DISTURBANCE WILL CROSS THE REGION TONIGHT. BUILDING HIGH
PRESSURE IS EXPECTED THROUGH THE WEEKEND...THOUGH CLOUDS WILL
REMAIN.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AN UTTERLY POOR SNOW CRYSTAL GROWTH HABIT EXISTS OVER THE CWA THIS
EVENING...AS EVIDENCED BY THE PINHEAD SIZED SNOWFLAKES/GRAINS THAT
HAVE BEEN SCATTERED ACROSS THE AREA IN THE FORM OF "FLURRIES." IN
ADDITION...AREAS JUST TO THE NORTH AND NORTHWEST OF OUR CWA HAVE
STARTED TO REPORT FREEZING DRIZZLE. THIS SEEMS LIKELY TO CONTINUE
TO FILTER INTO AT LEAST THE NORTHERN REACHES OF THE CWA AS
MOISTURE INCREASES...BUT STILL LITTLE MOISTURE EXISTS ABOVE ABOUT
THE -8C ISOTHERM. AS SUCH...WHILE DEEPER MOISTURE MAY ALLOW SOME
TREND TOWARD SNOW SHOWER ACTIVITY...IT SEEMS INSUFFICIENT TO
PRECLUDE FREEZING DRIZZLE FROM CONTINUING TO DEVELOP IN THE
NORTHERN PORTIONS OF THE CWA.

ADDITIONALLY...WITH AN INCOMING SHORT WAVE TROUGH AND A BIT OF
ELEVATED MOISTURE...SOME SEEDER-FEEDER TYPE OF SNOW FLURRY ACTION
DOES SEEM POSSIBLE FOR A SHORT WINDOW AS THE WAVE TRACKS
THROUGH...HOWEVER MODEL CROSS SECTIONS...TIME HEIGHT
SECTIONS...AND PLAN DEPICTIONS ALL GENERALLY REVEAL A QUICK TREND
TOWARD ZERO MICROBARS/SEC OF LAYER NEGATIVE OMEGA VALUES BETWEEN
00Z AND 06Z THIS EVENING. AS A RESULT...WITH DRY AIR BETWEEN THE
TWO MOIST LAYERS...WEAKENING LIFT ALOFT...AND POOR CRYSTAL GROWTH
BELOW...IT WOULD SEEM JUST A GENERAL EXPANSION IN THE FLURRIES FOR
A FEW HOURS AS THE WAVE TRACKS THROUGH SHOULD BE THE MAIN PROBLEM
FOR THE NIGHT OVER THE REST OF THE CWA. UNFORTUNATELY...ROAD
TEMPERATURES HAVE TRENDED NEAR FREEZING THROUGH THE EVENING...SO
REPORTS OF NUMEROUS ACCIDENTS HAVE COME IN ACROSS THE I-70 AND
SOUTH CORRIDOR AS LIGHT SNOW INITIALLY MELTED THEN REFROZE ON
ROADWAYS. LUCKILY ENOUGH...THIS WAVE IS TRACKING THROUGH RATHER
QUICKLY...AND AFTER ITS PASSAGE...EVEN BOUNDARY LAYER RH VALUES
START TO FALL OFF A BIT...SO IT WOULD SEEM EVEN THE POOR GROWTH
HABIT MAY DETERIORATE BY MORNING. FRIES

&&

.SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY/...
SFC HIGH PRES IS PROGGED TO BLD IN UNDER UPR TROFG OVR THE GT LKS
FRI...ENDING ANY LINGERING MRNG SNW SHWRS. THE SFC HIGH IS EXPD TO
BRING DRY WEA THRU THE WKEND...THOUGH PERSISTENT MSTR BLO AN
INVERSION MAY KEEP SKIES MCLDY. A SHRTWV MOVG ACRS THE SERN CONUS
LT SAT/SAT NGT IS NOW PROGGED TO STAY FAR ENOUGH S TO REMOVE ALL
PCPN FM THE FCST FOR AREAS S OF PIT. A WK SHRTWV IS PROGGED FOR
ERLY SUN ACRS THE GT LKS...BUT WITH A LACK OF DEEP MSTR AND THE
SFC HIGH OVERHEAD KEPT THE FCST DRY.

SLGTLY BLO AVG TEMPS SHOULD RTN TO NR SEASONAL LVLS BY SUN.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
WHILE THE MODELS AGREE ON A DEEPENING UPPER LEVEL TROUGH TO CLOSE
OFF OVER THE GREAT LAKES THROUGH THE PERIOD THE DETAILS OF HOW
THIS EXACTLY UNFOLDS WILL BE CRITICAL. BY MONDAY SOUTHERN STREAM
SHORTWAVE AHEAD OF MAIN NORTHERN STREAM UPPER TROUGH DIGGING INTO
THE NORTHERN PLAINS WILL PRODUCE LOW PRESSURE ACROSS THE CAROLINAS
MOVING OFF SHORE OF THE EAST COAST. THE SOUTHEAST RIDGES MAY BE
BRUSHED BY LIGHT RAIN FROM THIS SYSTEM. NEXT UP IS DEEPENING LOW
PRESSURE OVER THE OHIO VALLEY AHEAD OF SHARPLY DIGGING UPPER
TROUGH AND CLOSED LOW MOVING INTO THE WESTERN GREAT LAKES. UPPER
OHIO VALLEY LOOKS TO BE ON THE WARM SIDE OF THE SYSTEM TUESDAY
INTO WEDNESDAY WITH RAIN...FOLLOWED BY STRONG COLD FRONT AND COLD
ADVECTION LATER WEDNESDAY NIGHT AND THURSDAY WITH SNOW SHOWERS.
WITH SUCH A STRONG SYSTEM ALOFT AND FAST DEEPENING LOW PRESSURE AT
THE SURFACE TIMING OF COLD AIR AND EXACT TRACK WILL LIKELY CHANGE
AS WE GET CLOSER TO CHRISTMAS. ALL IN ALL PREVIOUS FORECAST IS
LITTLE CHANGED WITH ONLY MINOR ADJUSTMENTS BASED ON NEWEST WPC
EXTENDED PROGS.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
MVFR CIGS EXPECTED OVERNIGHT WITH SITES ALONG AND NORTH OF
INTERSTATE 80 POTENTIALLY SEEING IFR CIGS DEVELOP DURING PERIODS
OF LIGHT SNOW. THERE IS A SLIGHT CHANCE THAT LIGHT FREEZING
DRIZZLE MAY OCCUR AND SPREAD FROM NORTH TO SOUTH OVERNIGHT AS
MOISTURE DECREASES ALOFT LEAVING ONLY LOW LEVEL MOISTURE IN PLACE
TRAPPED UNDER THE INVERSION IN TEMPERATURES NOT SUFFICIENTLY COLD
FOR ICE CRYSTALS TO DEVELOP...BUT CONFIDENCE IS NOT HIGH ENOUGH
TO INCLUDE IN TAFS AT THIS TIME. POTENTIAL FOR FREEZING DRIZZLE
WILL LIKELY BE OVER BY MID MORNING AS MOISTURE POOL BECOMES TOO
SHALLOW.


OUTLOOK.../FRIDAY NIGHT THROUGH TUESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...WINTER WEATHER ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
     PAZ007>009-013>016-022.
WV...NONE.

&&

$$






000
FXUS61 KPBZ 190603
AFDPBZ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
103 AM EST FRI DEC 19 2014

.SYNOPSIS...
A WEAK DISTURBANCE WILL CROSS THE REGION TONIGHT. BUILDING HIGH
PRESSURE IS EXPECTED THROUGH THE WEEKEND...THOUGH CLOUDS WILL
REMAIN.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AN UTTERLY POOR SNOW CRYSTAL GROWTH HABIT EXISTS OVER THE CWA THIS
EVENING...AS EVIDENCED BY THE PINHEAD SIZED SNOWFLAKES/GRAINS THAT
HAVE BEEN SCATTERED ACROSS THE AREA IN THE FORM OF "FLURRIES." IN
ADDITION...AREAS JUST TO THE NORTH AND NORTHWEST OF OUR CWA HAVE
STARTED TO REPORT FREEZING DRIZZLE. THIS SEEMS LIKELY TO CONTINUE
TO FILTER INTO AT LEAST THE NORTHERN REACHES OF THE CWA AS
MOISTURE INCREASES...BUT STILL LITTLE MOISTURE EXISTS ABOVE ABOUT
THE -8C ISOTHERM. AS SUCH...WHILE DEEPER MOISTURE MAY ALLOW SOME
TREND TOWARD SNOW SHOWER ACTIVITY...IT SEEMS INSUFFICIENT TO
PRECLUDE FREEZING DRIZZLE FROM CONTINUING TO DEVELOP IN THE
NORTHERN PORTIONS OF THE CWA.

ADDITIONALLY...WITH AN INCOMING SHORT WAVE TROUGH AND A BIT OF
ELEVATED MOISTURE...SOME SEEDER-FEEDER TYPE OF SNOW FLURRY ACTION
DOES SEEM POSSIBLE FOR A SHORT WINDOW AS THE WAVE TRACKS
THROUGH...HOWEVER MODEL CROSS SECTIONS...TIME HEIGHT
SECTIONS...AND PLAN DEPICTIONS ALL GENERALLY REVEAL A QUICK TREND
TOWARD ZERO MICROBARS/SEC OF LAYER NEGATIVE OMEGA VALUES BETWEEN
00Z AND 06Z THIS EVENING. AS A RESULT...WITH DRY AIR BETWEEN THE
TWO MOIST LAYERS...WEAKENING LIFT ALOFT...AND POOR CRYSTAL GROWTH
BELOW...IT WOULD SEEM JUST A GENERAL EXPANSION IN THE FLURRIES FOR
A FEW HOURS AS THE WAVE TRACKS THROUGH SHOULD BE THE MAIN PROBLEM
FOR THE NIGHT OVER THE REST OF THE CWA. UNFORTUNATELY...ROAD
TEMPERATURES HAVE TRENDED NEAR FREEZING THROUGH THE EVENING...SO
REPORTS OF NUMEROUS ACCIDENTS HAVE COME IN ACROSS THE I-70 AND
SOUTH CORRIDOR AS LIGHT SNOW INITIALLY MELTED THEN REFROZE ON
ROADWAYS. LUCKILY ENOUGH...THIS WAVE IS TRACKING THROUGH RATHER
QUICKLY...AND AFTER ITS PASSAGE...EVEN BOUNDARY LAYER RH VALUES
START TO FALL OFF A BIT...SO IT WOULD SEEM EVEN THE POOR GROWTH
HABIT MAY DETERIORATE BY MORNING. FRIES

&&

.SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY/...
SFC HIGH PRES IS PROGGED TO BLD IN UNDER UPR TROFG OVR THE GT LKS
FRI...ENDING ANY LINGERING MRNG SNW SHWRS. THE SFC HIGH IS EXPD TO
BRING DRY WEA THRU THE WKEND...THOUGH PERSISTENT MSTR BLO AN
INVERSION MAY KEEP SKIES MCLDY. A SHRTWV MOVG ACRS THE SERN CONUS
LT SAT/SAT NGT IS NOW PROGGED TO STAY FAR ENOUGH S TO REMOVE ALL
PCPN FM THE FCST FOR AREAS S OF PIT. A WK SHRTWV IS PROGGED FOR
ERLY SUN ACRS THE GT LKS...BUT WITH A LACK OF DEEP MSTR AND THE
SFC HIGH OVERHEAD KEPT THE FCST DRY.

SLGTLY BLO AVG TEMPS SHOULD RTN TO NR SEASONAL LVLS BY SUN.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
WHILE THE MODELS AGREE ON A DEEPENING UPPER LEVEL TROUGH TO CLOSE
OFF OVER THE GREAT LAKES THROUGH THE PERIOD THE DETAILS OF HOW
THIS EXACTLY UNFOLDS WILL BE CRITICAL. BY MONDAY SOUTHERN STREAM
SHORTWAVE AHEAD OF MAIN NORTHERN STREAM UPPER TROUGH DIGGING INTO
THE NORTHERN PLAINS WILL PRODUCE LOW PRESSURE ACROSS THE CAROLINAS
MOVING OFF SHORE OF THE EAST COAST. THE SOUTHEAST RIDGES MAY BE
BRUSHED BY LIGHT RAIN FROM THIS SYSTEM. NEXT UP IS DEEPENING LOW
PRESSURE OVER THE OHIO VALLEY AHEAD OF SHARPLY DIGGING UPPER
TROUGH AND CLOSED LOW MOVING INTO THE WESTERN GREAT LAKES. UPPER
OHIO VALLEY LOOKS TO BE ON THE WARM SIDE OF THE SYSTEM TUESDAY
INTO WEDNESDAY WITH RAIN...FOLLOWED BY STRONG COLD FRONT AND COLD
ADVECTION LATER WEDNESDAY NIGHT AND THURSDAY WITH SNOW SHOWERS.
WITH SUCH A STRONG SYSTEM ALOFT AND FAST DEEPENING LOW PRESSURE AT
THE SURFACE TIMING OF COLD AIR AND EXACT TRACK WILL LIKELY CHANGE
AS WE GET CLOSER TO CHRISTMAS. ALL IN ALL PREVIOUS FORECAST IS
LITTLE CHANGED WITH ONLY MINOR ADJUSTMENTS BASED ON NEWEST WPC
EXTENDED PROGS.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
MVFR CIGS EXPECTED OVERNIGHT WITH SITES ALONG AND NORTH OF
INTERSTATE 80 POTENTIALLY SEEING IFR CIGS DEVELOP DURING PERIODS
OF LIGHT SNOW. THERE IS A SLIGHT CHANCE THAT LIGHT FREEZING
DRIZZLE MAY OCCUR AND SPREAD FROM NORTH TO SOUTH OVERNIGHT AS
MOISTURE DECREASES ALOFT LEAVING ONLY LOW LEVEL MOISTURE IN PLACE
TRAPPED UNDER THE INVERSION IN TEMPERATURES NOT SUFFICIENTLY COLD
FOR ICE CRYSTALS TO DEVELOP...BUT CONFIDENCE IS NOT HIGH ENOUGH
TO INCLUDE IN TAFS AT THIS TIME. POTENTIAL FOR FREEZING DRIZZLE
WILL LIKELY BE OVER BY MID MORNING AS MOISTURE POOL BECOMES TOO
SHALLOW.


OUTLOOK.../FRIDAY NIGHT THROUGH TUESDAY/...
STRATUS AND RESTRICTIONS MAY PERSIST INTO THE WEEKEND. NEXT STORM
SYSTEM WILL BRING RESTRICTIONS TUESDAY.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...WINTER WEATHER ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
     PAZ007>009-013>016-022.
WV...NONE.

&&

$$






000
FXUS61 KCTP 190455
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1155 PM EST THU DEC 18 2014

.SYNOPSIS...
COLD NORTHWEST WINDS WILL KEEP FLURRIES AND SCATTERED LIGHT SNOW
SHOWERS OVER THE NORTH AND WEST INTO FRIDAY MORNING. HIGH
PRESSURE WILL SLIDE DOWN FROM THE UPPER GREAT LAKES AND PROVIDE A
GENERALLY FAIR PERIOD FOR MOST OF THE WEEKEND.

AN UNSETTLED PATTERN WILL SET UP IN THE FIRST PART OF THE NEW
WEEK. A WEAK LOW PRESSURE AREA COULD AFFECT THE AREA MONDAY. THEN
A MORE SIGNIFICANT STORM IS EXPECTED MOVE INTO THE REGION FOR
CHRISTMAS EVE...FOLLOWED BY STRONG WINDS AND SCATTERED SNOW
SHOWERS FOR CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
AFTER COORDINATING WITH SURROUNDING OFFICES..HAVE OPTED FOR AN
ADVISORY FOR FREEZING DRIZZLE OVER MY NORTHERN COUNTIES. STILL NOT
EXPECTING MUCH...BUT TRAVEL COULD BE IMPACTED SO WE HAVE THE
HEADLINE OUT THROUGH 7 AM.

NO OTHER CHANGES MADE TO THE NEAR TERM FORECAST.

HAVE TINKERED WITH THE NEAR TERM POPS AS MAINLY LIGHT SNOW
SHOWERS OR FLURRIES SEEM THE MOST LIKELY OUTCOME THIS EVENING AND
OVERNIGHT FOR MUCH OF MY WESTERN AND NORTHERN FORECAST AREA. WEST
FACING SLOPES OF THE WEST CENTRAL MOUNTAINS AND LAUREL HIGHLANDS
MAY SEE A LOCALIZED COATING OF SNOW LATE TONIGHT INTO FRI MORNING.

OTHERWISE EXPECT WIDESPREAD STRATUS TO PERSIST ACROSS MOST OF
CENTRAL PA. THE SOUTHEAST WILL LIKELY SEE SOME DISSIPATION BY
FRIDAY MORNING. SURFACE HIGH CENTERED OVER THE NORTHERN GREAT
LAKES AND EASTERN QUEBEC WILL KEEP NORTH/NORTHWEST BOUNDARY LAYER
FLOW GOING THROUGH FRI MORNING...TRANSLATING TO SFC WINDS IN THE 7
TO 11 MPH RANGE.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
UPPER FORCING SLIDES EAST OF THE REGION EARLY FRIDAY MORNING...
WITH EXPANSIVE SURFACE HIGH PRESSURE BUILDING OVER THE AREA IN THE
AFTERNOON. THUS...THE AMOUNT/COVERAGE OF THE SNOW SHOWERS AND
FLURRIES SHOULD DIMINISH COMPLETELY ON FRIDAY. MINS WILL STAY A
LITTLE MILDER THAN CLIMO WITH CLOUDS AROUND. MAXES ON FRIDAY VERY
SIMILAR TO TODAY...WITH 30S FOR THE MOUNTAINS AND NEAR 40 IN THE
LOW LANDS WITH THE HELP OF SOME DOWNSLOPE WARMING.

&&

.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE WILL SHIFT SLOWLY EASTWARD FROM THE GREAT LAKES
INTO NORTHERN NEW ENGLAND BY 12Z MONDAY. RESIDUAL LOW LEVEL
MOISTURE ALONG WITH NRN STREAM SHORTWAVE ENERGY ATTEMPTING TO
UNDERCUT AN UPPER RIDGE/HIGH HEIGHTS MIGRATING OVER SOUTHEASTERN
CANADA SHOULD LIMIT SUN INTERVALS---HOWEVER THE SUN SHOULD AT
LEAST MAKE A BRIEF APPEARANCE THIS WEEKEND. SPLIT FLOW REGIME
ACROSS THE LOWER 48 WILL TRANSITION TO A HIGHLY AMPLIFIED PATTERN
BY EARLY NEXT WEEK ACROSS THE LOWER 48...WITH A DEEP NEGATIVELY
TILTED TROUGH EVOLVING OVER THE EASTERN 1/3RD OF THE CONUS.

THE MODELS SEEM TO BE FORMING A CONSENSUS ON THE PESKY LOW
THAT REFUSES TO BE WELL FORECAST...LIFTING IT SLOWLY FROM FL
PANHANDLE NNEWD JUST OFF THE EAST COAST SUN-MON ALONG A LOW LEVEL
BAROCLINIC ZONE THAT MAY NOT BUDGE PAST THE GULF STREAM AS THE
FLOW ALOFT TURNS SOUTHWESTERLY/PARALLEL TO THE COASTAL FRONT.
INCREASED POPS FOR MONDAY OVER THE SE BASED ON MULTI-MODEL/WPC
BLEND. COMPLEX SFC PATTERN WITH SOME HINTS AT LOW LEVEL CAD ALONG
WITH WAA ALOFT VIA SLY FLOW COULD MAKE FOR A MESSY MIXED PTYPE
TRANSITION.

AN INTENSE TRIPLE POINT SYSTEM DEVELOPING ON DEC 23-24 WILL
LIKELY STEAL THE HEADLINES GIVEN ITS TIMING AND LARGE PORTION OF
REAL ESTATE THAT WILL BE AFFECTED. WHILE THE DETAILS REMAIN
UNCLEAR AT THIS POINT...TEMPERATURES SHOULD BE WARM ENOUGH TO
SUPPORT RAIN ON THE FRONT SIDE OF THE SYSTEM BEFORE BRISK WNW
WINDS DRIVE STRONG CAA EAST OF THE APPALACHIANS. THE TIMING OF THE
COLD/OCCLUDED FRONT WILL BE KEY FOR PRECIPITATION TRANSITION FROM
RAIN TO SNOW SHOWERS. AS THE SYSTEM SPINS UP INTO EASTERN
CANADA...THE STRONG CAA CIRCULATING THROUGH THE GREAT LAKES AND OH
VLY SHOULD LEAD TO LAKE EFFECT/UPSLOPE/WRAP AROUND SNOW SHOWERS
OVER THE WESTERN ALLEGHENIES BY CHRISTMAS DAY. A PERIOD OF STRONG
GUSTY WINDS ARE HIGHLY PROBABLE AS THE DYNAMIC SYSTEM INTENSIFIES
SHIFTING NWWD FROM NEW ENGLAND INTO ONTARIO/QUEBEC.

THE TAKE HOME MESSAGE IS THAT A VOLATILE PERIOD OF WEATHER WILL
IMPACT THE AREA THROUGH CHRISTMAS DAY WITH POTENTIAL WIND...RAIN
AND SNOW IMPACTS ALL ON THE TABLE. STAY TUNED.

&&

.AVIATION /05Z FRIDAY THROUGH TUESDAY/... LOW LVL MOISTURE
TRAPPED BENEATH INVERSION AND NORTHWEST FLOW OVER THE EASTERN
GLAKS WILL KEEP STRATO CU IN PLACE ACROSS MOST OF CENTRAL PA
THROUGH TONIGHT. LATEST MDL SOUNDINGS POINT TOWARD PREDOMINANTLY
IFR CIGS/VSBYS AT KBFD AND KJST. THE MODELS SHOW SOME VARIATION
BUT MVFR CIGS AT ALL OTHER TAF SITES EITHER ARE CURRENTLY
OCCURRINGOR WILL OCCUR BETWEEN 06Z TO 12Z. IPT SHOULD DEVELOP
BETWEEN 09Z TO 12Z.

A TROUGH OF LOW PRESSURE WILL PUSH THRU THE REGION OVERNIGHT...PERHAPS
PRODUCING A PERIOD OF STEADIER LGT SNOW AT KBFD AND KJST BTWN 06Z-
12Z FRIDAY WITH VSBYS IN THE 2 TO 4SM RANGE. SKIES WILL STEADILY
IMPROVE AS THE DAY CONTINUES WITH VFR CIGS BY 15Z AT ALL TAF
SITES. EXPECT REDUCING CONDITIONS TOMORROW EVENING AT ONLY BFD
AND POSSIBLY JST.


OUTLOOK...

FRI...EARLY AM -SHSN/REDUCED VSBYS POSS AT KJST.

SAT-SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 AM EST FRIDAY FOR PAZ004>006-
010-011-037.

&&

$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...DEVOIR
LONG TERM...STEINBUGL
AVIATION...DEVOIR/CERU




000
FXUS61 KCTP 190455
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1155 PM EST THU DEC 18 2014

.SYNOPSIS...
COLD NORTHWEST WINDS WILL KEEP FLURRIES AND SCATTERED LIGHT SNOW
SHOWERS OVER THE NORTH AND WEST INTO FRIDAY MORNING. HIGH
PRESSURE WILL SLIDE DOWN FROM THE UPPER GREAT LAKES AND PROVIDE A
GENERALLY FAIR PERIOD FOR MOST OF THE WEEKEND.

AN UNSETTLED PATTERN WILL SET UP IN THE FIRST PART OF THE NEW
WEEK. A WEAK LOW PRESSURE AREA COULD AFFECT THE AREA MONDAY. THEN
A MORE SIGNIFICANT STORM IS EXPECTED MOVE INTO THE REGION FOR
CHRISTMAS EVE...FOLLOWED BY STRONG WINDS AND SCATTERED SNOW
SHOWERS FOR CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
AFTER COORDINATING WITH SURROUNDING OFFICES..HAVE OPTED FOR AN
ADVISORY FOR FREEZING DRIZZLE OVER MY NORTHERN COUNTIES. STILL NOT
EXPECTING MUCH...BUT TRAVEL COULD BE IMPACTED SO WE HAVE THE
HEADLINE OUT THROUGH 7 AM.

NO OTHER CHANGES MADE TO THE NEAR TERM FORECAST.

HAVE TINKERED WITH THE NEAR TERM POPS AS MAINLY LIGHT SNOW
SHOWERS OR FLURRIES SEEM THE MOST LIKELY OUTCOME THIS EVENING AND
OVERNIGHT FOR MUCH OF MY WESTERN AND NORTHERN FORECAST AREA. WEST
FACING SLOPES OF THE WEST CENTRAL MOUNTAINS AND LAUREL HIGHLANDS
MAY SEE A LOCALIZED COATING OF SNOW LATE TONIGHT INTO FRI MORNING.

OTHERWISE EXPECT WIDESPREAD STRATUS TO PERSIST ACROSS MOST OF
CENTRAL PA. THE SOUTHEAST WILL LIKELY SEE SOME DISSIPATION BY
FRIDAY MORNING. SURFACE HIGH CENTERED OVER THE NORTHERN GREAT
LAKES AND EASTERN QUEBEC WILL KEEP NORTH/NORTHWEST BOUNDARY LAYER
FLOW GOING THROUGH FRI MORNING...TRANSLATING TO SFC WINDS IN THE 7
TO 11 MPH RANGE.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
UPPER FORCING SLIDES EAST OF THE REGION EARLY FRIDAY MORNING...
WITH EXPANSIVE SURFACE HIGH PRESSURE BUILDING OVER THE AREA IN THE
AFTERNOON. THUS...THE AMOUNT/COVERAGE OF THE SNOW SHOWERS AND
FLURRIES SHOULD DIMINISH COMPLETELY ON FRIDAY. MINS WILL STAY A
LITTLE MILDER THAN CLIMO WITH CLOUDS AROUND. MAXES ON FRIDAY VERY
SIMILAR TO TODAY...WITH 30S FOR THE MOUNTAINS AND NEAR 40 IN THE
LOW LANDS WITH THE HELP OF SOME DOWNSLOPE WARMING.

&&

.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE WILL SHIFT SLOWLY EASTWARD FROM THE GREAT LAKES
INTO NORTHERN NEW ENGLAND BY 12Z MONDAY. RESIDUAL LOW LEVEL
MOISTURE ALONG WITH NRN STREAM SHORTWAVE ENERGY ATTEMPTING TO
UNDERCUT AN UPPER RIDGE/HIGH HEIGHTS MIGRATING OVER SOUTHEASTERN
CANADA SHOULD LIMIT SUN INTERVALS---HOWEVER THE SUN SHOULD AT
LEAST MAKE A BRIEF APPEARANCE THIS WEEKEND. SPLIT FLOW REGIME
ACROSS THE LOWER 48 WILL TRANSITION TO A HIGHLY AMPLIFIED PATTERN
BY EARLY NEXT WEEK ACROSS THE LOWER 48...WITH A DEEP NEGATIVELY
TILTED TROUGH EVOLVING OVER THE EASTERN 1/3RD OF THE CONUS.

THE MODELS SEEM TO BE FORMING A CONSENSUS ON THE PESKY LOW
THAT REFUSES TO BE WELL FORECAST...LIFTING IT SLOWLY FROM FL
PANHANDLE NNEWD JUST OFF THE EAST COAST SUN-MON ALONG A LOW LEVEL
BAROCLINIC ZONE THAT MAY NOT BUDGE PAST THE GULF STREAM AS THE
FLOW ALOFT TURNS SOUTHWESTERLY/PARALLEL TO THE COASTAL FRONT.
INCREASED POPS FOR MONDAY OVER THE SE BASED ON MULTI-MODEL/WPC
BLEND. COMPLEX SFC PATTERN WITH SOME HINTS AT LOW LEVEL CAD ALONG
WITH WAA ALOFT VIA SLY FLOW COULD MAKE FOR A MESSY MIXED PTYPE
TRANSITION.

AN INTENSE TRIPLE POINT SYSTEM DEVELOPING ON DEC 23-24 WILL
LIKELY STEAL THE HEADLINES GIVEN ITS TIMING AND LARGE PORTION OF
REAL ESTATE THAT WILL BE AFFECTED. WHILE THE DETAILS REMAIN
UNCLEAR AT THIS POINT...TEMPERATURES SHOULD BE WARM ENOUGH TO
SUPPORT RAIN ON THE FRONT SIDE OF THE SYSTEM BEFORE BRISK WNW
WINDS DRIVE STRONG CAA EAST OF THE APPALACHIANS. THE TIMING OF THE
COLD/OCCLUDED FRONT WILL BE KEY FOR PRECIPITATION TRANSITION FROM
RAIN TO SNOW SHOWERS. AS THE SYSTEM SPINS UP INTO EASTERN
CANADA...THE STRONG CAA CIRCULATING THROUGH THE GREAT LAKES AND OH
VLY SHOULD LEAD TO LAKE EFFECT/UPSLOPE/WRAP AROUND SNOW SHOWERS
OVER THE WESTERN ALLEGHENIES BY CHRISTMAS DAY. A PERIOD OF STRONG
GUSTY WINDS ARE HIGHLY PROBABLE AS THE DYNAMIC SYSTEM INTENSIFIES
SHIFTING NWWD FROM NEW ENGLAND INTO ONTARIO/QUEBEC.

THE TAKE HOME MESSAGE IS THAT A VOLATILE PERIOD OF WEATHER WILL
IMPACT THE AREA THROUGH CHRISTMAS DAY WITH POTENTIAL WIND...RAIN
AND SNOW IMPACTS ALL ON THE TABLE. STAY TUNED.

&&

.AVIATION /05Z FRIDAY THROUGH TUESDAY/... LOW LVL MOISTURE
TRAPPED BENEATH INVERSION AND NORTHWEST FLOW OVER THE EASTERN
GLAKS WILL KEEP STRATO CU IN PLACE ACROSS MOST OF CENTRAL PA
THROUGH TONIGHT. LATEST MDL SOUNDINGS POINT TOWARD PREDOMINANTLY
IFR CIGS/VSBYS AT KBFD AND KJST. THE MODELS SHOW SOME VARIATION
BUT MVFR CIGS AT ALL OTHER TAF SITES EITHER ARE CURRENTLY
OCCURRINGOR WILL OCCUR BETWEEN 06Z TO 12Z. IPT SHOULD DEVELOP
BETWEEN 09Z TO 12Z.

A TROUGH OF LOW PRESSURE WILL PUSH THRU THE REGION OVERNIGHT...PERHAPS
PRODUCING A PERIOD OF STEADIER LGT SNOW AT KBFD AND KJST BTWN 06Z-
12Z FRIDAY WITH VSBYS IN THE 2 TO 4SM RANGE. SKIES WILL STEADILY
IMPROVE AS THE DAY CONTINUES WITH VFR CIGS BY 15Z AT ALL TAF
SITES. EXPECT REDUCING CONDITIONS TOMORROW EVENING AT ONLY BFD
AND POSSIBLY JST.


OUTLOOK...

FRI...EARLY AM -SHSN/REDUCED VSBYS POSS AT KJST.

SAT-SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 AM EST FRIDAY FOR PAZ004>006-
010-011-037.

&&

$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...DEVOIR
LONG TERM...STEINBUGL
AVIATION...DEVOIR/CERU




000
FXUS61 KCTP 190455
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1155 PM EST THU DEC 18 2014

.SYNOPSIS...
COLD NORTHWEST WINDS WILL KEEP FLURRIES AND SCATTERED LIGHT SNOW
SHOWERS OVER THE NORTH AND WEST INTO FRIDAY MORNING. HIGH
PRESSURE WILL SLIDE DOWN FROM THE UPPER GREAT LAKES AND PROVIDE A
GENERALLY FAIR PERIOD FOR MOST OF THE WEEKEND.

AN UNSETTLED PATTERN WILL SET UP IN THE FIRST PART OF THE NEW
WEEK. A WEAK LOW PRESSURE AREA COULD AFFECT THE AREA MONDAY. THEN
A MORE SIGNIFICANT STORM IS EXPECTED MOVE INTO THE REGION FOR
CHRISTMAS EVE...FOLLOWED BY STRONG WINDS AND SCATTERED SNOW
SHOWERS FOR CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
AFTER COORDINATING WITH SURROUNDING OFFICES..HAVE OPTED FOR AN
ADVISORY FOR FREEZING DRIZZLE OVER MY NORTHERN COUNTIES. STILL NOT
EXPECTING MUCH...BUT TRAVEL COULD BE IMPACTED SO WE HAVE THE
HEADLINE OUT THROUGH 7 AM.

NO OTHER CHANGES MADE TO THE NEAR TERM FORECAST.

HAVE TINKERED WITH THE NEAR TERM POPS AS MAINLY LIGHT SNOW
SHOWERS OR FLURRIES SEEM THE MOST LIKELY OUTCOME THIS EVENING AND
OVERNIGHT FOR MUCH OF MY WESTERN AND NORTHERN FORECAST AREA. WEST
FACING SLOPES OF THE WEST CENTRAL MOUNTAINS AND LAUREL HIGHLANDS
MAY SEE A LOCALIZED COATING OF SNOW LATE TONIGHT INTO FRI MORNING.

OTHERWISE EXPECT WIDESPREAD STRATUS TO PERSIST ACROSS MOST OF
CENTRAL PA. THE SOUTHEAST WILL LIKELY SEE SOME DISSIPATION BY
FRIDAY MORNING. SURFACE HIGH CENTERED OVER THE NORTHERN GREAT
LAKES AND EASTERN QUEBEC WILL KEEP NORTH/NORTHWEST BOUNDARY LAYER
FLOW GOING THROUGH FRI MORNING...TRANSLATING TO SFC WINDS IN THE 7
TO 11 MPH RANGE.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
UPPER FORCING SLIDES EAST OF THE REGION EARLY FRIDAY MORNING...
WITH EXPANSIVE SURFACE HIGH PRESSURE BUILDING OVER THE AREA IN THE
AFTERNOON. THUS...THE AMOUNT/COVERAGE OF THE SNOW SHOWERS AND
FLURRIES SHOULD DIMINISH COMPLETELY ON FRIDAY. MINS WILL STAY A
LITTLE MILDER THAN CLIMO WITH CLOUDS AROUND. MAXES ON FRIDAY VERY
SIMILAR TO TODAY...WITH 30S FOR THE MOUNTAINS AND NEAR 40 IN THE
LOW LANDS WITH THE HELP OF SOME DOWNSLOPE WARMING.

&&

.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE WILL SHIFT SLOWLY EASTWARD FROM THE GREAT LAKES
INTO NORTHERN NEW ENGLAND BY 12Z MONDAY. RESIDUAL LOW LEVEL
MOISTURE ALONG WITH NRN STREAM SHORTWAVE ENERGY ATTEMPTING TO
UNDERCUT AN UPPER RIDGE/HIGH HEIGHTS MIGRATING OVER SOUTHEASTERN
CANADA SHOULD LIMIT SUN INTERVALS---HOWEVER THE SUN SHOULD AT
LEAST MAKE A BRIEF APPEARANCE THIS WEEKEND. SPLIT FLOW REGIME
ACROSS THE LOWER 48 WILL TRANSITION TO A HIGHLY AMPLIFIED PATTERN
BY EARLY NEXT WEEK ACROSS THE LOWER 48...WITH A DEEP NEGATIVELY
TILTED TROUGH EVOLVING OVER THE EASTERN 1/3RD OF THE CONUS.

THE MODELS SEEM TO BE FORMING A CONSENSUS ON THE PESKY LOW
THAT REFUSES TO BE WELL FORECAST...LIFTING IT SLOWLY FROM FL
PANHANDLE NNEWD JUST OFF THE EAST COAST SUN-MON ALONG A LOW LEVEL
BAROCLINIC ZONE THAT MAY NOT BUDGE PAST THE GULF STREAM AS THE
FLOW ALOFT TURNS SOUTHWESTERLY/PARALLEL TO THE COASTAL FRONT.
INCREASED POPS FOR MONDAY OVER THE SE BASED ON MULTI-MODEL/WPC
BLEND. COMPLEX SFC PATTERN WITH SOME HINTS AT LOW LEVEL CAD ALONG
WITH WAA ALOFT VIA SLY FLOW COULD MAKE FOR A MESSY MIXED PTYPE
TRANSITION.

AN INTENSE TRIPLE POINT SYSTEM DEVELOPING ON DEC 23-24 WILL
LIKELY STEAL THE HEADLINES GIVEN ITS TIMING AND LARGE PORTION OF
REAL ESTATE THAT WILL BE AFFECTED. WHILE THE DETAILS REMAIN
UNCLEAR AT THIS POINT...TEMPERATURES SHOULD BE WARM ENOUGH TO
SUPPORT RAIN ON THE FRONT SIDE OF THE SYSTEM BEFORE BRISK WNW
WINDS DRIVE STRONG CAA EAST OF THE APPALACHIANS. THE TIMING OF THE
COLD/OCCLUDED FRONT WILL BE KEY FOR PRECIPITATION TRANSITION FROM
RAIN TO SNOW SHOWERS. AS THE SYSTEM SPINS UP INTO EASTERN
CANADA...THE STRONG CAA CIRCULATING THROUGH THE GREAT LAKES AND OH
VLY SHOULD LEAD TO LAKE EFFECT/UPSLOPE/WRAP AROUND SNOW SHOWERS
OVER THE WESTERN ALLEGHENIES BY CHRISTMAS DAY. A PERIOD OF STRONG
GUSTY WINDS ARE HIGHLY PROBABLE AS THE DYNAMIC SYSTEM INTENSIFIES
SHIFTING NWWD FROM NEW ENGLAND INTO ONTARIO/QUEBEC.

THE TAKE HOME MESSAGE IS THAT A VOLATILE PERIOD OF WEATHER WILL
IMPACT THE AREA THROUGH CHRISTMAS DAY WITH POTENTIAL WIND...RAIN
AND SNOW IMPACTS ALL ON THE TABLE. STAY TUNED.

&&

.AVIATION /05Z FRIDAY THROUGH TUESDAY/... LOW LVL MOISTURE
TRAPPED BENEATH INVERSION AND NORTHWEST FLOW OVER THE EASTERN
GLAKS WILL KEEP STRATO CU IN PLACE ACROSS MOST OF CENTRAL PA
THROUGH TONIGHT. LATEST MDL SOUNDINGS POINT TOWARD PREDOMINANTLY
IFR CIGS/VSBYS AT KBFD AND KJST. THE MODELS SHOW SOME VARIATION
BUT MVFR CIGS AT ALL OTHER TAF SITES EITHER ARE CURRENTLY
OCCURRINGOR WILL OCCUR BETWEEN 06Z TO 12Z. IPT SHOULD DEVELOP
BETWEEN 09Z TO 12Z.

A TROUGH OF LOW PRESSURE WILL PUSH THRU THE REGION OVERNIGHT...PERHAPS
PRODUCING A PERIOD OF STEADIER LGT SNOW AT KBFD AND KJST BTWN 06Z-
12Z FRIDAY WITH VSBYS IN THE 2 TO 4SM RANGE. SKIES WILL STEADILY
IMPROVE AS THE DAY CONTINUES WITH VFR CIGS BY 15Z AT ALL TAF
SITES. EXPECT REDUCING CONDITIONS TOMORROW EVENING AT ONLY BFD
AND POSSIBLY JST.


OUTLOOK...

FRI...EARLY AM -SHSN/REDUCED VSBYS POSS AT KJST.

SAT-SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 AM EST FRIDAY FOR PAZ004>006-
010-011-037.

&&

$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...DEVOIR
LONG TERM...STEINBUGL
AVIATION...DEVOIR/CERU




000
FXUS61 KCTP 190455
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1155 PM EST THU DEC 18 2014

.SYNOPSIS...
COLD NORTHWEST WINDS WILL KEEP FLURRIES AND SCATTERED LIGHT SNOW
SHOWERS OVER THE NORTH AND WEST INTO FRIDAY MORNING. HIGH
PRESSURE WILL SLIDE DOWN FROM THE UPPER GREAT LAKES AND PROVIDE A
GENERALLY FAIR PERIOD FOR MOST OF THE WEEKEND.

AN UNSETTLED PATTERN WILL SET UP IN THE FIRST PART OF THE NEW
WEEK. A WEAK LOW PRESSURE AREA COULD AFFECT THE AREA MONDAY. THEN
A MORE SIGNIFICANT STORM IS EXPECTED MOVE INTO THE REGION FOR
CHRISTMAS EVE...FOLLOWED BY STRONG WINDS AND SCATTERED SNOW
SHOWERS FOR CHRISTMAS DAY.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
AFTER COORDINATING WITH SURROUNDING OFFICES..HAVE OPTED FOR AN
ADVISORY FOR FREEZING DRIZZLE OVER MY NORTHERN COUNTIES. STILL NOT
EXPECTING MUCH...BUT TRAVEL COULD BE IMPACTED SO WE HAVE THE
HEADLINE OUT THROUGH 7 AM.

NO OTHER CHANGES MADE TO THE NEAR TERM FORECAST.

HAVE TINKERED WITH THE NEAR TERM POPS AS MAINLY LIGHT SNOW
SHOWERS OR FLURRIES SEEM THE MOST LIKELY OUTCOME THIS EVENING AND
OVERNIGHT FOR MUCH OF MY WESTERN AND NORTHERN FORECAST AREA. WEST
FACING SLOPES OF THE WEST CENTRAL MOUNTAINS AND LAUREL HIGHLANDS
MAY SEE A LOCALIZED COATING OF SNOW LATE TONIGHT INTO FRI MORNING.

OTHERWISE EXPECT WIDESPREAD STRATUS TO PERSIST ACROSS MOST OF
CENTRAL PA. THE SOUTHEAST WILL LIKELY SEE SOME DISSIPATION BY
FRIDAY MORNING. SURFACE HIGH CENTERED OVER THE NORTHERN GREAT
LAKES AND EASTERN QUEBEC WILL KEEP NORTH/NORTHWEST BOUNDARY LAYER
FLOW GOING THROUGH FRI MORNING...TRANSLATING TO SFC WINDS IN THE 7
TO 11 MPH RANGE.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
UPPER FORCING SLIDES EAST OF THE REGION EARLY FRIDAY MORNING...
WITH EXPANSIVE SURFACE HIGH PRESSURE BUILDING OVER THE AREA IN THE
AFTERNOON. THUS...THE AMOUNT/COVERAGE OF THE SNOW SHOWERS AND
FLURRIES SHOULD DIMINISH COMPLETELY ON FRIDAY. MINS WILL STAY A
LITTLE MILDER THAN CLIMO WITH CLOUDS AROUND. MAXES ON FRIDAY VERY
SIMILAR TO TODAY...WITH 30S FOR THE MOUNTAINS AND NEAR 40 IN THE
LOW LANDS WITH THE HELP OF SOME DOWNSLOPE WARMING.

&&

.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE WILL SHIFT SLOWLY EASTWARD FROM THE GREAT LAKES
INTO NORTHERN NEW ENGLAND BY 12Z MONDAY. RESIDUAL LOW LEVEL
MOISTURE ALONG WITH NRN STREAM SHORTWAVE ENERGY ATTEMPTING TO
UNDERCUT AN UPPER RIDGE/HIGH HEIGHTS MIGRATING OVER SOUTHEASTERN
CANADA SHOULD LIMIT SUN INTERVALS---HOWEVER THE SUN SHOULD AT
LEAST MAKE A BRIEF APPEARANCE THIS WEEKEND. SPLIT FLOW REGIME
ACROSS THE LOWER 48 WILL TRANSITION TO A HIGHLY AMPLIFIED PATTERN
BY EARLY NEXT WEEK ACROSS THE LOWER 48...WITH A DEEP NEGATIVELY
TILTED TROUGH EVOLVING OVER THE EASTERN 1/3RD OF THE CONUS.

THE MODELS SEEM TO BE FORMING A CONSENSUS ON THE PESKY LOW
THAT REFUSES TO BE WELL FORECAST...LIFTING IT SLOWLY FROM FL
PANHANDLE NNEWD JUST OFF THE EAST COAST SUN-MON ALONG A LOW LEVEL
BAROCLINIC ZONE THAT MAY NOT BUDGE PAST THE GULF STREAM AS THE
FLOW ALOFT TURNS SOUTHWESTERLY/PARALLEL TO THE COASTAL FRONT.
INCREASED POPS FOR MONDAY OVER THE SE BASED ON MULTI-MODEL/WPC
BLEND. COMPLEX SFC PATTERN WITH SOME HINTS AT LOW LEVEL CAD ALONG
WITH WAA ALOFT VIA SLY FLOW COULD MAKE FOR A MESSY MIXED PTYPE
TRANSITION.

AN INTENSE TRIPLE POINT SYSTEM DEVELOPING ON DEC 23-24 WILL
LIKELY STEAL THE HEADLINES GIVEN ITS TIMING AND LARGE PORTION OF
REAL ESTATE THAT WILL BE AFFECTED. WHILE THE DETAILS REMAIN
UNCLEAR AT THIS POINT...TEMPERATURES SHOULD BE WARM ENOUGH TO
SUPPORT RAIN ON THE FRONT SIDE OF THE SYSTEM BEFORE BRISK WNW
WINDS DRIVE STRONG CAA EAST OF THE APPALACHIANS. THE TIMING OF THE
COLD/OCCLUDED FRONT WILL BE KEY FOR PRECIPITATION TRANSITION FROM
RAIN TO SNOW SHOWERS. AS THE SYSTEM SPINS UP INTO EASTERN
CANADA...THE STRONG CAA CIRCULATING THROUGH THE GREAT LAKES AND OH
VLY SHOULD LEAD TO LAKE EFFECT/UPSLOPE/WRAP AROUND SNOW SHOWERS
OVER THE WESTERN ALLEGHENIES BY CHRISTMAS DAY. A PERIOD OF STRONG
GUSTY WINDS ARE HIGHLY PROBABLE AS THE DYNAMIC SYSTEM INTENSIFIES
SHIFTING NWWD FROM NEW ENGLAND INTO ONTARIO/QUEBEC.

THE TAKE HOME MESSAGE IS THAT A VOLATILE PERIOD OF WEATHER WILL
IMPACT THE AREA THROUGH CHRISTMAS DAY WITH POTENTIAL WIND...RAIN
AND SNOW IMPACTS ALL ON THE TABLE. STAY TUNED.

&&

.AVIATION /05Z FRIDAY THROUGH TUESDAY/... LOW LVL MOISTURE
TRAPPED BENEATH INVERSION AND NORTHWEST FLOW OVER THE EASTERN
GLAKS WILL KEEP STRATO CU IN PLACE ACROSS MOST OF CENTRAL PA
THROUGH TONIGHT. LATEST MDL SOUNDINGS POINT TOWARD PREDOMINANTLY
IFR CIGS/VSBYS AT KBFD AND KJST. THE MODELS SHOW SOME VARIATION
BUT MVFR CIGS AT ALL OTHER TAF SITES EITHER ARE CURRENTLY
OCCURRINGOR WILL OCCUR BETWEEN 06Z TO 12Z. IPT SHOULD DEVELOP
BETWEEN 09Z TO 12Z.

A TROUGH OF LOW PRESSURE WILL PUSH THRU THE REGION OVERNIGHT...PERHAPS
PRODUCING A PERIOD OF STEADIER LGT SNOW AT KBFD AND KJST BTWN 06Z-
12Z FRIDAY WITH VSBYS IN THE 2 TO 4SM RANGE. SKIES WILL STEADILY
IMPROVE AS THE DAY CONTINUES WITH VFR CIGS BY 15Z AT ALL TAF
SITES. EXPECT REDUCING CONDITIONS TOMORROW EVENING AT ONLY BFD
AND POSSIBLY JST.


OUTLOOK...

FRI...EARLY AM -SHSN/REDUCED VSBYS POSS AT KJST.

SAT-SUN...NO SIG WX EXPECTED.

MON...LOW CIGS WITH LGT RAIN/SNOW POSSIBLE.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 AM EST FRIDAY FOR PAZ004>006-
010-011-037.

&&

$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...DEVOIR
LONG TERM...STEINBUGL
AVIATION...DEVOIR/CERU




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