000
FXUS61 KCTP 220743
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
343 AM EDT WED MAY 22 2013

.SYNOPSIS...
LOW PRESSURE OVER THE MIDWEST WILL TRACK NORTHEAST THROUGH THE
LOWER GREAT LAKES REGION TODAY AND UP THE ST. LAWRENCE RIVER
VALLEY ON THURSDAY. A COLD FRONT TRAILING THE LOW WILL CROSS THE
REGION ON THURSDAY...FOLLOWED BY A SECONDARY COLD FRONT ON FRIDAY.
BEHIND THE SECOND FRONT...A CANADIAN HIGH PRESSURE SYSTEM WILL
USHER IN COOLER AND DRIER AIR THAT WILL KEEP TEMPERATURES BELOW
NORMAL FOR MEMORIAL DAY WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
REGIONAL RADAR SHOWS ISOLD SHOWERS/TSTMS MOVG ACRS THE NRN MTS IN
ASSOC WITH 35-40KT SWLY LLJ. THERE COULD BE A DIFFUSE SFC BNDRY
OR MSTR CONVERGENCE AXIS EXTENDING SWWD ALONG THE ALLEGHENY FRONT
FROM WEAK LOW OVER UPSTATE NY. SHOWER ACTIVITY INVOF NRN WV HAS
BEEN DISSIPATING OVER THE LAST 2 HOURS. ASIDE FROM A WDLY SCT
SHOWER OR ISOLD TSTM OVER THE N-CNTRL TO NERN ZONES...EXPECT A
MAINLY DRY PERIOD THROUGH THE PRE-DAWN HOURS INTO THE EARLY
MORNING...WITH SOME PATCHY FOG ACRS THE MID-LWR SUSQ VLY. TEMPS
WILL REMAIN VERY MILD WITH MORNING LOWS IN THE MID-UPR 60S.

ALOFT...SUMMER-LIKE UPPER RIDGE OVER THE SE STATES WILL DRIFT EWD
INTO WRN ATLC TDY. MEANWHILE...SHORTWAVES CURRENTLY ROTATING ACRS
HUDSON BAY AND OVER THE N-CNTRL PLAINS INVOF SIOUX CITY SOUTH
DAKOTA WILL MERGE AND FORM AN EXPANSIVE 500MB TROUGH FROM SERN
CANADA TO THE CENTRAL GULF COAST BY 12Z THU. AT THE SFC...A LOW IS
FCST TO TRACK ENEWD FM THE UPPER MIDWEST ACRS LWR MI INTO THE ERN
GRT LKS WITH TRAILING COLD FRONT PROGRESSING EWD THRU THE OH VLY.

MEAN SWLY FLOW ON NW SIDE OF DEPARTING UPPER-LEVEL RIDGE WILL
BRING ANOTHER VERY WARM DAY TO CNTRL PA WITH AFTN TEMPS IN THE
80S OR ABOUT +10F ABOVE NORMAL. DEEP LAYER MSTR WILL ALSO REMAIN
HIGH/ABOVE NORMAL WITH PWATS 1-1.5 INCHES. SENSIBLE WX CONCERNS IN
THE NEAR TERM REMAIN FOCUSED ON DIURNAL CONVECTION WITH THE NW 1/2
OF THE CWA IN SLGT RISK. WHILE DESTABILIZATION/INSTABILITY IS NOT
EXPECTED TO BE AS ROBUST AS YESTERDAY...LG SCALE FORCING SHOULD BE
ON THE UP-TICK AS UPPER- LEVEL TROUGH AND ASSOCD HT FALLS SHIFT
EWD INTO THE UPPER OH VLY BY 00Z. 700MB TEMPS ARE ALSO PROGGED TO
BE ABOUT 2-3F COOLER. THE LLVL FOCUS WILL REMAIN SOMEWHAT NEBULOUS
AS THE MAIN SYNOPTIC COLD FRONT REMAINS WELL TO THE WEST OF THE
AREA. A SUBTLE LEE-TROUGH MAY PROVIDE AN INITIAL FOCUS FOR MULTI-
CELL CLUSTERS ACRS PORTIONS OF CNTRL AND ERN PA. HOWEVER THE MAIN
SVR THREAT WILL BE ACRS WRN SXNS CLOSER TO THE STRONG FLOW ALOFT.
21Z SREF DATA SHOWS SWLY LLJ INCREASING TO +2-3SD ACRS WRN PA
WHICH COULD AID IN UPSCALE GROWTH OF POSSIBLE MCS OVER OH/LWR
MI/LAKE ERIE WITH PEAK INTENSITY BTWN APPROX 21-03Z.

&&

.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
CONTINUED EWD PROGRESSION OF THE EXPANSIVE ERN CONUS TROUGH IS
EXPECTED THIS PERIOD...HOWEVER IT MAY BE AT SLOWER PACE AS SOME
MODEL DATA IS TRENDING SLOWER/SHARPER BY THE END OF THE PERIOD.
THE ATTENDANT COLD FRONT WILL TRAVERSE THE AREA DURING THE AFTN
AND EVENING BEFORE EXITING THE ERN PART OF THE CWA AROUND MIDNIGHT.

GENERALLY WEAK INSTABILITY IS PROGGED IN THE PRE-FRONTAL WARM
SECTOR. HOWEVER...MODERATE FLOW/0-6KM SHEAR AROUND 40 KTS COULD
ALLOW FOR A FEW STRONG STORMS TO ORGANIZE WHERE POCKETS OF GREAT
HEATING/DESTABILIZATION CAN OCCUR. THIS APPEARS MOST LKLY OVER THE
ERN 1/3 OF THE CWA...WHICH IS HIGHLIGHTED BY THE SPC DAY 2 SEE TEXT
CATEGORICAL OUTLOOK.

A LIGHTER...DEFORMATION PCPN AXIS IS PROGGED TO SET UP OVER THE
AREA THURS NIGHT AS A SHORTWAVE EMBEDDED IN THE LARGER-SCALE
TROUGH DIGS FROM THE GRT LKS TWD WV. THERE ARE SOME NOTABLE MODEL
DIFFS HEADING INTO DAY 3 SURROUNDING THE DEPTH AND SPEED OF THE H5
TROUGH CROSSING THE MID-ATLC REGION. MORE ON THIS IN THE LONG TERM
SECTION.

WINDS WILL SHIFT TO THE NNW INTO THE EARLY MORNING HOURS ON
FRIDAY. THIS WILL DIRECT MUCH COOLER AND DRIER AIR MASS TOWARD THE
REGION WHICH SHOULD ARRIVE AROUND DAYBREAK FRIDAY.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
BEHIND THE DEPARTING COLD FRONT...A STG AND LARGE ANTICYCLONE
SHOULD DOMINATE PATTERN IN THE FRI-MON TIMEFRAME...BUILDING SEWD
FROM NUNAVUT CANADA ACROSS THE GRT LKS INTO THE NORTHEAST. AN
UNSEASONABLY COLD/DRY AIRMASS WILL ACCOMPANY THE HIGH RESULTING IN
BELOW NORMAL TEMPS FOR MEMORIAL DAY WEEKEND. ECENS MOS DATA SHOWS
TEMPS ON FRI/SAT STRUGGLING TO CRACK THE 60F MARK LOCALLY...WITH
SEVERAL OPPORTUNITIES FOR A LATE-SEASON FROST OVER THE NRN MTNS
SAT/SUN/MON MORNINGS. HOWEVER CURRENT LOW TEMPS REMAIN ABOVE 40
FOR MOST OF THE REGION WITH THE EXCEPTION BEING ALONG THE NEW YORK
BORDER. WINDS SHOULD REMAIN GUSTY SATURDAY MORNING. THE BETTER
CHANCE FOR FROST WILL BE SUNDAY MORNING...TEMPERATURES WILL BE
SLIGHTLY WARMER BUT THE WINDS SHOULD BE LIGHT TO CALM. THERE
SHOULD BE A MODERATION INTO THE MIDDLE OF NEXT WEEK WITH TEMPS
GETTING BACK TO NEAR NORMAL AROUND 5/28.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
NOT A LOT OF CHANGE. STILL AN ISOLATED STORM POSSIBLE NEAR
THE NY BORDER OVERNIGHT. ALSO MAYBE A BRIEF SHOWER CLOSE
TO JST...LEFT OUT THE FCST FOR NOW.

EARLIER DISCUSSION BELOW.

MAIN FRONT AND ACTION ACROSS NY STATE...TOOK MENTION OF SHOWERS
AND STORMS OUT OF ALL SITES BUT BFD. LEFT VCSH IN BFD UNTIL 03Z.

SOME FOG LATER...BASED MAINLY ON WHAT WENT ON LAST NIGHT.

NOT SEEING MUCH DIFFERENCE FOR WED...VERY SIMILAR TO TODAY...
WILL BE IN THE WARM SECTOR...WITH NOT MUCH GOING ON.

MORE IN THE WAY OF WIDESPREAD SHOWERS AND STORMS LATER THU
INTO THU NIGHT. COULD BY BUSY ACROSS THE FAR SE THU NIGHT...
IF A WAVE FORMS ON THE FRONT.

COOLER AND BREEZY FOR FRIDAY INTO SUNDAY...AS A STRONG COLD
FRONT DROPS SE OF PA.

HO
.OUTLOOK...
THU...SCT THUNDERSTORM IMPACTS POSSIBLE...MAINLY IN THE PM.
FRI-MON...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...CERU/STEINBUGL
AVIATION...LAMBERT/MARTIN

000
FXUS61 KCTP 220342
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1142 PM EDT TUE MAY 21 2013

.SYNOPSIS...
A WARM AND HUMID SUMMERTIME AIR MASS WILL CONTINUE TO BRING WELL
ABOVE NORMAL TEMPERATURES TO CENTRAL PENNSYLVANIA THROUGH
WEDNESDAY. A COLD FRONT WILL CROSS THE REGION ON THURSDAY. A
SECOND FRONT WILL PUSH THROUGH ON FRIDAY AND USHER IN HIGH
PRESSURE FROM CENTRAL CANADA INTO THE NORTHEAST AND MID-ATLANTIC
STATES. THIS HIGH WILL BRING COOLER AND DRIER AIR TO THE AREA FOR
MEMORIAL DAY WEEKEND THAT COULD LAST RIGHT THROUGH MONDAY.

&&

.NEAR TERM /UNTIL 7 AM WEDNESDAY MORNING/...
STORMS ONLY NOW TOUCHING NRN WARREN COUNTY AS BEST MOISTURE
CONVERGENCE STAYS ALONG THE NRN BORDER. TEMPS HAVE DROPPED OFF AT
THE SFC...BUT INSTABILITY STILL HIGH ALOFT. ISOLATED/SCT SHOWERS
AND STORMS MOVING THROUGH PIT AND CRW RIGHT NOW ARE ON TRACK TO
MOVE INTO THE SWRN COS BY MIDNIGHT AND COULD LAST INTO THE MIDDLE
OF THE NIGHT IF THEY HOLD TOGETHER. RUC HOLDS ONTO THE CELLS FOR
ANOTHER HOUR OR TWO...BUT THEN DISSIPATES THEM. THIS SEEMS
PLAUSIBLE SINCE THEY ARE NOT LOOKING VERY HEALTHY RIGHT NOW. THE
CLUSTER FROM WV SEEMS TO HAVE MORE ORGANIZATION AND WILL KEEP ON
WITH LOW CHC POPS FOR THE SW INTO THE WEE HOURS. THE RUC AND HRRR
ARE AT ODDS WITH EACH OTHER WRT THE CONVECTION ALONG THE NY
BORDER. RUC CONTINUES IT THROUGH MUCH OF THE NIGHT...BUT HRRR
BREAKS IT APART. WILL ALSO HOLD THE LINE WITH CHC POPS FOR THE NRN
TIER OF COUNTIES SEEING NO PREPONDERANCE OF GUIDANCE THAT IS
AGAINST SOME MEASURE OF ELEVATED INSTABILITY AND POTENTIAL FOR
CONVECTION THERE. WILL KEEP MENTIONS OF PATCHY FOG AS WELL..WITH
MAINLY CLEAR SKIES RIGHT NOW AND HIGH DEWPOINTS. CLOUDS FROM
UPSTREAM WILL PROBABLY LEVEL TEMPS OFF IN A FEW HOURS...BUT FOG
MAY YET CREEP INTO THE VALLEYS.

&&

.SHORT TERM /7 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
A S/W MOVG EWD ACRS THE UPPER MS VLY INVOF IA WILL PHASE WITH A
CANADIAN UPPER LOW/TROUGH DROPPING SWD ACRS HUDSON/JAMES BAY DURING
THE DAY WEDNESDAY...REACHING THE MIDWEST BY F48. AT THE SFC...A
COLD FRONT PUSHING EWD THRU THE OH VLY WILL BE THE MAIN FOCUS FOR
TSTM DEVELOPMENT/SVR POTENTIAL THIS PERIOD.

AM CLOUDS WITH SOME SPOTTY SHOWERS AND AREAS OF 1-2SM FIG WILL
COMBINE WITH WEAK RIDGING WITHIN THE PREDOMINANT SWRLY FLOW
ALOFT...TO LIMIT DIURNAL HEATING TO SOME EXTENT ACRS THE DAY 2 SPC
SLGT RISK AREA - WHICH COVERS NEARLY ALL OF THE CWA WITH THE
EXCEPTION OF THE FAR SERN ZONES. ALTHOUGH LOW TO MID LEVEL WINDS
WILL BE STRONGEST ACROSS THE NW HALF OF PENN...LATEST SREF AND SHORT
RANGE MODEL GUIDANCE PAINTS THE GREATEST PROBABILITY FOR CAPE
GREATER THAN 1200 J/KG ACROSS THE LOWER SUSQ VALLEY LATE WEDNESDAY
AFTERNOON.

DESPITE THE TEMPERED DESTABILIZATION...EXPECT AN AFTN INCREASE IN
TSTM COVERAGE /WITH LOWER CLOUD BASES COMPARED TO TUESDAY`S/ ALONG
WITH SOME PICK-UP IN INTENSITY AS BELT OF STRONGER FLOW ALOFT SHIFTS
EWD AHEAD OF THE MID-UPPER TROUGH. BANDS OF TSTMS CAPABLE OF
PRODUCING DMGG WNDS/MARGINAL HAIL WILL BE POSSIBLE AND THUS WILL
CONTINUE TO HIGHLIGHT AN ELEVATED SVR WX THREAT IN THE HWO FOR
WEDNESDAY. BETTER FORCING PORTENDS HIGHER POPS RANGING FROM THE
MED-HIGH CHC RANGE IN THE SE TO LOW LKLYS IN THE NW. SHOWERS/TSTMS
MAY PERSIST AFTER DARK INTO WED NGT.

MAX TEMPS WILL LIKELY BE 3-5F LOWER THAN TUESDAY...BUT STILL AROUND
12F ABOVE NORMAL.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
THE UPPER RIDGE WILL BREAK DOWN AS A TROUGH DEEPENS INTO THE GREAT
LAKES REGION BY THURSDAY AFTERNOON. THIS WILL CORRESPOND WITH A
FRONT MOVING THROUGH THE NORTHEAST THURSDAY. TIMING FOR THIS FRONT
IS STILL VARYING BUT CURRENT EC BRINGS THE FRONT THROUGH MIDDAY
THURSDAY. COUPLE THIS FRONT WITH DAYTIME HEATING AND STRONG
SOUTHWEST FLOW...THURSDAY COULD BE THE BEST DAY FOR DAYTIME
CONVECTION THIS WEEK. BOTH THE OPERATIONAL GFS AND THE ECMWF CONTINUE
TO OUTPUT THE POSSIBILITY OF A LOW LEVEL JET THURSDAY
AFTERNOON...WHICH WITH 35-40KTS OF DEEP-LAYER SHEAR WILL ONLY
INCREASE PROBABILITIES FOR PRECIPITATION THURSDAY AFTERNOON. THIS
EASTERN NORTH AMERICA TROUGH AXIS EXTENDING FROM JAMES BAY SWD
THRU THE GRT LKS/MID- SOUTH TO THE CENTRAL GULF COAST WILL PUSH
SLOWLY EWD AND SHOULD REACH THE EAST COAST BY 00Z SAT. THIS WILL
ALLOW FOR PERSISTENT INSTABILITY OVER THE AREA THROUGH THE END OF
THE WEEK...WITH COLD NORTHWESTERLY FLOW BEHIND THE FRONT. THE
GUIDANCE IS SHOWING SOME NOTABLE DIFFS WITH THE H5 SYSTEM. THE
NAM/GFS/GEFS ARE SLOWER AND SHARPER WITH TROUGH AS IT CROSSES THE
OH VLY INTO THE MID- ATLC. THE 00Z GFS EVEN CLOSES OFF THE H5 LOW
OVER NRN VA FRI EVE. THE LAST TWO RUNS OF THE CMC HAVE BEEN TRYING
TO GENERATE A TROPICAL CYCLONE- LIKE SYSTEM NEAR THE OUTER BANKS.
THE KNOWN SLOW/TROPICAL BIASES OF THE NAM/CMC AND STRONG/CLOSED
SOLN OF THE GFS LEADS TO A UKMET/ECMWF PREFERRED SOLN WHICH FAVORS
MORE EWD PROGRESSION WITH THE TROUGH AND ITS ASSOCD COLD FRONT.

BEHIND THE DEPARTING COLD FRONT...A STG AND LARGE ANTICYCLONE
SHOULD DOMINATE PATTERN IN THE FRI-MON TIMEFRAME...BUILDING SEWD
FROM NUNAVUT CANADA ACROSS THE GRT LKS INTO THE NORTHEAST. AN
UNSEASONABLY COLD/DRY AIRMASS WILL ACCOMPANY THE HIGH RESULTING IN
BELOW NORMAL TEMPS FOR MEMORIAL DAY WEEKEND. ECENS MOS DATA SHOWS
TEMPS ON FRI/SAT STRUGGLING TO CRACK THE 60F MARK LOCALLY...WITH
SEVERAL OPPORTUNITIES FOR A LATE-SEASON FROST OVER THE NRN MTNS
SAT/SUN/MON MORNINGS. HOWEVER CURRENT LOW TEMPS REMAIN ABOVE 40
FOR MOST OF THE REGION WITH THE EXCEPTION BEING ALONG THE NEW YORK
BORDER. WINDS SHOULD REMAIN GUSTY SATURDAY MORNING. THE BETTER
CHANCE FOR FROST WILL BE SUNDAY MORNING...TEMPERATURES WILL BE
SLIGHTLY WARMER BUT THE WINDS SHOULD BE LIGHT TO CALM. THERE
SHOULD BE A MODERATION INTO THE MIDDLE OF NEXT WEEK WITH TEMPS
GETTING BACK TO NEAR NORMAL AROUND 5/28.

&&

.AVIATION /04Z WEDNESDAY THROUGH SUNDAY/...
NOT A LOT OF CHANGE. STILL AN ISOLATED STORM POSSIBLE NEAR
THE NY BORDER OVERNIGHT. ALSO MAYBE A BRIEF SHOWER CLOSE
TO JST...LEFT OUT THE FCST FOR NOW.

EARLIER DISCUSSION BELOW.

MAIN FRONT AND ACTION ACROSS NY STATE...TOOK MENTION OF SHOWERS
AND STORMS OUT OF ALL SITES BUT BFD. LEFT VCSH IN BFD UNTIL 03Z.

SOME FOG LATER...BASED MAINLY ON WHAT WENT ON LAST NIGHT.

NOT SEEING MUCH DIFFERENCE FOR WED...VERY SIMILAR TO TODAY...
WILL BE IN THE WARM SECTOR...WITH NOT MUCH GOING ON.

MORE IN THE WAY OF WIDESPREAD SHOWERS AND STORMS LATER THU
INTO THU NIGHT. COULD BY BUSY ACROSS THE FAR SE THU NIGHT...
IF A WAVE FORMS ON THE FRONT.

COOLER AND BREEZY FOR FRIDAY INTO SUNDAY...AS A STRONG COLD
FRONT DROPS SE OF PA.

HO
.OUTLOOK...
THU...SCT THUNDERSTORM IMPACTS POSSIBLE...MAINLY IN THE PM.
FRI-MON...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...LAMBERT/STEINBUGL
NEAR TERM...DANGELO
SHORT TERM...LAMBERT/STEINBUGL
LONG TERM...CERU/STEINBUGL
AVIATION...LAMBERT/MARTIN

000
FXUS61 KCTP 220207
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1007 PM EDT TUE MAY 21 2013

.SYNOPSIS...
A WARM AND HUMID SUMMERTIME AIR MASS WILL CONTINUE TO BRING WELL
ABOVE NORMAL TEMPERATURES TO CENTRAL PENNSYLVANIA THROUGH
WEDNESDAY. A COLD FRONT WILL CROSS THE REGION ON THURSDAY. A
SECOND FRONT WILL PUSH THROUGH ON FRIDAY AND USHER IN HIGH
PRESSURE FROM CENTRAL CANADA INTO THE NORTHEAST AND MID-ATLANTIC
STATES. THIS HIGH WILL BRING COOLER AND DRIER AIR TO THE AREA FOR
MEMORIAL DAY WEEKEND THAT COULD LAST RIGHT THROUGH MONDAY.

&&

.NEAR TERM /UNTIL 7 AM WEDNESDAY MORNING/...
STORMS ONLY NOW TOUCHING NRN WARREN COUNTY AS BEST MOISTURE
CONVERGENCE STAYS ALONG THE NRN BORDER. TEMPS HAVE DROPPED OFF AT
THE SFC...BUT INSTABILITY STILL HIGH ALOFT. ISOLATED/SCT SHOWERS
AND STORMS MOVING THROUGH PIT AND CRW RIGHT NOW ARE ON TRACK TO
MOVE INTO THE SWRN COS BY MIDNIGHT AND COULD LAST INTO THE MIDDLE
OF THE NIGHT IF THEY HOLD TOGETHER. RUC HOLDS ONTO THE CELLS FOR
ANOTHER HOUR OR TWO...BUT THEN DISSIPATES THEM. THIS SEEMS
PLAUSIBLE SINCE THEY ARE NOT LOOKING VERY HEALTHY RIGHT NOW. THE
CLUSTER FROM WV SEEMS TO HAVE MORE ORGANIZATION AND WILL KEEP ON
WITH LOW CHC POPS FOR THE SW INTO THE WEE HOURS. THE RUC AND HRRR
ARE AT ODDS WITH EACH OTHER WRT THE CONVECTION ALONG THE NY
BORDER. RUC CONTINUES IT THROUGH MUCH OF THE NIGHT...BUT HRRR
BREAKS IT APART. WILL ALSO HOLD THE LINE WITH CHC POPS FOR THE NRN
TIER OF COUNTIES SEEING NO PREPONDERANCE OF GUIDANCE THAT IS
AGAINST SOME MEASURE OF ELEVATED INSTABILITY AND POTENTIAL FOR
CONVECTION THERE. WILL KEEP MENTIONS OF PATCHY FOG AS WELL..WITH
MAINLY CLEAR SKIES RIGHT NOW AND HIGH DEWPOINTS. CLOUDS FROM
UPSTREAM WILL PROBABLY LEVEL TEMPS OFF IN A FEW HOURS...BUT FOG
MAY YET CREEP INTO THE VALLEYS.

&&

.SHORT TERM /7 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
A S/W MOVG EWD ACRS THE UPPER MS VLY INVOF IA WILL PHASE WITH A
CANADIAN UPPER LOW/TROUGH DROPPING SWD ACRS HUDSON/JAMES BAY DURING
THE DAY WEDNESDAY...REACHING THE MIDWEST BY F48. AT THE SFC...A
COLD FRONT PUSHING EWD THRU THE OH VLY WILL BE THE MAIN FOCUS FOR
TSTM DEVELOPMENT/SVR POTENTIAL THIS PERIOD.

AM CLOUDS WITH SOME SPOTTY SHOWERS AND AREAS OF 1-2SM FIG WILL
COMBINE WITH WEAK RIDGING WITHIN THE PREDOMINANT SWRLY FLOW
ALOFT...TO LIMIT DIURNAL HEATING TO SOME EXTENT ACRS THE DAY 2 SPC
SLGT RISK AREA - WHICH COVERS NEARLY ALL OF THE CWA WITH THE
EXCEPTION OF THE FAR SERN ZONES. ALTHOUGH LOW TO MID LEVEL WINDS
WILL BE STRONGEST ACROSS THE NW HALF OF PENN...LATEST SREF AND SHORT
RANGE MODEL GUIDANCE PAINTS THE GREATEST PROBABILITY FOR CAPE
GREATER THAN 1200 J/KG ACROSS THE LOWER SUSQ VALLEY LATE WEDNESDAY
AFTERNOON.

DESPITE THE TEMPERED DESTABILIZATION...EXPECT AN AFTN INCREASE IN
TSTM COVERAGE /WITH LOWER CLOUD BASES COMPARED TO TUESDAY`S/ ALONG
WITH SOME PICK-UP IN INTENSITY AS BELT OF STRONGER FLOW ALOFT SHIFTS
EWD AHEAD OF THE MID-UPPER TROUGH. BANDS OF TSTMS CAPABLE OF
PRODUCING DMGG WNDS/MARGINAL HAIL WILL BE POSSIBLE AND THUS WILL
CONTINUE TO HIGHLIGHT AN ELEVATED SVR WX THREAT IN THE HWO FOR
WEDNESDAY. BETTER FORCING PORTENDS HIGHER POPS RANGING FROM THE
MED-HIGH CHC RANGE IN THE SE TO LOW LKLYS IN THE NW. SHOWERS/TSTMS
MAY PERSIST AFTER DARK INTO WED NGT.

MAX TEMPS WILL LIKELY BE 3-5F LOWER THAN TUESDAY...BUT STILL AROUND
12F ABOVE NORMAL.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
THE UPPER RIDGE WILL BREAK DOWN AS A TROUGH DEEPENS INTO THE GREAT
LAKES REGION BY THURSDAY AFTERNOON. THIS WILL CORRESPOND WITH A
FRONT MOVING THROUGH THE NORTHEAST THURSDAY. TIMING FOR THIS FRONT
IS STILL VARYING BUT CURRENT EC BRINGS THE FRONT THROUGH MIDDAY
THURSDAY. COUPLE THIS FRONT WITH DAYTIME HEATING AND STRONG
SOUTHWEST FLOW...THURSDAY COULD BE THE BEST DAY FOR DAYTIME
CONVECTION THIS WEEK. BOTH THE OPERATIONAL GFS AND THE ECMWF CONTINUE
TO OUTPUT THE POSSIBILITY OF A LOW LEVEL JET THURSDAY
AFTERNOON...WHICH WITH 35-40KTS OF DEEP-LAYER SHEAR WILL ONLY
INCREASE PROBABILITIES FOR PRECIPITATION THURSDAY AFTERNOON. THIS
EASTERN NORTH AMERICA TROUGH AXIS EXTENDING FROM JAMES BAY SWD
THRU THE GRT LKS/MID- SOUTH TO THE CENTRAL GULF COAST WILL PUSH
SLOWLY EWD AND SHOULD REACH THE EAST COAST BY 00Z SAT. THIS WILL
ALLOW FOR PERSISTENT INSTABILITY OVER THE AREA THROUGH THE END OF
THE WEEK...WITH COLD NORTHWESTERLY FLOW BEHIND THE FRONT. THE
GUIDANCE IS SHOWING SOME NOTABLE DIFFS WITH THE H5 SYSTEM. THE
NAM/GFS/GEFS ARE SLOWER AND SHARPER WITH TROUGH AS IT CROSSES THE
OH VLY INTO THE MID- ATLC. THE 00Z GFS EVEN CLOSES OFF THE H5 LOW
OVER NRN VA FRI EVE. THE LAST TWO RUNS OF THE CMC HAVE BEEN TRYING
TO GENERATE A TROPICAL CYCLONE- LIKE SYSTEM NEAR THE OUTER BANKS.
THE KNOWN SLOW/TROPICAL BIASES OF THE NAM/CMC AND STRONG/CLOSED
SOLN OF THE GFS LEADS TO A UKMET/ECMWF PREFERRED SOLN WHICH FAVORS
MORE EWD PROGRESSION WITH THE TROUGH AND ITS ASSOCD COLD FRONT.

BEHIND THE DEPARTING COLD FRONT...A STG AND LARGE ANTICYCLONE
SHOULD DOMINATE PATTERN IN THE FRI-MON TIMEFRAME...BUILDING SEWD
FROM NUNAVUT CANADA ACROSS THE GRT LKS INTO THE NORTHEAST. AN
UNSEASONABLY COLD/DRY AIRMASS WILL ACCOMPANY THE HIGH RESULTING IN
BELOW NORMAL TEMPS FOR MEMORIAL DAY WEEKEND. ECENS MOS DATA SHOWS
TEMPS ON FRI/SAT STRUGGLING TO CRACK THE 60F MARK LOCALLY...WITH
SEVERAL OPPORTUNITIES FOR A LATE-SEASON FROST OVER THE NRN MTNS
SAT/SUN/MON MORNINGS. HOWEVER CURRENT LOW TEMPS REMAIN ABOVE 40
FOR MOST OF THE REGION WITH THE EXCEPTION BEING ALONG THE NEW YORK
BORDER. WINDS SHOULD REMAIN GUSTY SATURDAY MORNING. THE BETTER
CHANCE FOR FROST WILL BE SUNDAY MORNING...TEMPERATURES WILL BE
SLIGHTLY WARMER BUT THE WINDS SHOULD BE LIGHT TO CALM. THERE
SHOULD BE A MODERATION INTO THE MIDDLE OF NEXT WEEK WITH TEMPS
GETTING BACK TO NEAR NORMAL AROUND 5/28.

&&

.AVIATION /02Z WEDNESDAY THROUGH SUNDAY/...
MAIN FRONT AND ACTION ACROSS NY STATE...TOOK MENTION OF SHOWERS
AND STORMS OUT OF ALL SITES BUT BFD. LEFT VCSH IN BFD UNTIL 03Z.

SOME FOG LATER...BASED MAINLY ON WHAT WENT ON LAST NIGHT.

NOT SEEING MUCH DIFFERENCE FOR WED...VERY SIMILAR TO TODAY...
WILL BE IN THE WARM SECTOR...WITH NOT MUCH GOING ON.

MORE IN THE WAY OF WIDESPREAD SHOWERS AND STORMS LATER THU
INTO THU NIGHT. COULD BY BUSY ACROSS THE FAR SE THU NIGHT...
IF A WAVE FORMS ON THE FRONT.

COOLER AND BREEZY FOR FRIDAY INTO SUNDAY...AS A STRONG COLD
FRONT DROPS SE OF PA.

HO
.OUTLOOK...
THU...SCT THUNDERSTORM IMPACTS POSSIBLE...MAINLY IN THE PM.
FRI-MON...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...LAMBERT/STEINBUGL
NEAR TERM...DANGELO
SHORT TERM...LAMBERT/STEINBUGL
LONG TERM...CERU/STEINBUGL
AVIATION...LAMBERT/MARTIN

000
FXUS61 KCTP 212352
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
752 PM EDT TUE MAY 21 2013

.SYNOPSIS...
A WARM AND HUMID...SUMMERTIME AIRMASS WILL CONTINUE TO BRING WELL
ABOVE NORMAL TEMPERATURES TO CENTRAL PENNSYLVANIA LATE TODAY THROUGH
WEDNESDAY. A COLD FRONT WILL CROSS THE REGION ON THURSDAY. A LARGE
AREA OF HIGH PRESSURE WILL BUILD SOUTHEAST FROM CENTRAL CANADA INTO
THE NORTHEAST AND MID-ATLANTIC STATES. THIS HIGH WILL BRING COOLER
AND DRIER AIR TO THE AREA FOR MEMORIAL DAY WEEKEND...THAT COULD
LAST RIGHT THROUGH MONDAY.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
LOTS OF CONVECTION TO THE NORTH ALONG THE WARM FRONT AND ALONG THE
LAKE ERIE SHORE LINE. ANOTHER CLUSTER OF STORMS OVER ERN OH
NEARING KPIT IS ALONG A WEAK SFC TROUGH PROGRESSING STEADILY
EASTWARD. HOWEVER...THE CAP HAS KEPT CONVECTION LOCALLY DOWN TO
ONE OR TWO CELLS WHICH HAVE SINCE DIED AS THEY MOVED QUICKLY OUT
OF THE NERN MTS. IN FACT...MOST OF THE CU HAVE JUST ABOUT
DISAPPEARED FROM THE CWA. THE CONGESTED CU OVER THE NW MTS ARE
THE ONLY LLVL CLOUDS. ABOVE THE SFC TROUGH IS A WEAK SHORT WAVE
MOVING EASTWARD. THE MSTR FLOWING INTO THIS FEATURE FROM THE SW IS
THUS FAR POTENT ENOUGH TO MAINTAIN DECENT INSTABILITY EVEN WITH
THE LOSS OF HEATING. AS THE TROUGH PASSES SLOWLY TONIGHT...IT
SHOULD CONTINUE TO MAKE ISOLD/SCT SHOWERS/TSTORMS. NO REAL SPEED
MAX SEEN IN THE WIND FIELDS SO THREAT FOR SEVERE SEEMS TO BE
DIMINISHING BUT CERTAINLY NOT OVER.

CONVECTION WILL GRADUALLY DIMINISH LATE TONIGHT WITH WIND BECOMING
LIGHT IN THE MUGGY AIRMASS. PATCHY FOG WILL FORM AFTER 07Z...AND
COULD BE LOCALLY DENSE IN THE VALLEYS WHERE RAINFALL DOES OCCUR.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
A S/W MOVG EWD ACRS THE UPPER MS VLY INVOF IA WILL PHASE WITH A
CANADIAN UPPER LOW/TROUGH DROPPING SWD ACRS HUDSON/JAMES BAY DURING
THE DAY WEDNESDAY...REACHING THE MIDWEST BY F48. AT THE SFC...A
COLD FRONT PUSHING EWD THRU THE OH VLY WILL BE THE MAIN FOCUS FOR
TSTM DEVELOPMENT/SVR POTENTIAL THIS PERIOD.

AM CLOUDS WITH SOME SPOTTY SHOWERS AND AREAS OF 1-2SM FIG WILL
COMBINE WITH WEAK RIDGING WITHIN THE PREDOMINANT SWRLY FLOW
ALOFT...TO LIMIT DIURNAL HEATING TO SOME EXTENT ACRS THE DAY 2 SPC
SLGT RISK AREA - WHICH COVERS NEARLY ALL OF THE CWA WITH THE
EXCEPTION OF THE FAR SERN ZONES. ALTHOUGH LOW TO MID LEVEL WINDS
WILL BE STRONGEST ACROSS THE NW HALF OF PENN...LATEST SREF AND SHORT
RANGE MODEL GUIDANCE PAINTS THE GREATEST PROBABILITY FOR CAPE
GREATER THAN 1200 J/KG ACROSS THE LOWER SUSQ VALLEY LATE WEDNESDAY
AFTERNOON.

DESPITE THE TEMPERED DESTABILIZATION...EXPECT AN AFTN INCREASE IN
TSTM COVERAGE /WITH LOWER CLOUD BASES COMPARED TO TUESDAY`S/ ALONG
WITH SOME PICK-UP IN INTENSITY AS BELT OF STRONGER FLOW ALOFT SHIFTS
EWD AHEAD OF THE MID-UPPER TROUGH. BANDS OF TSTMS CAPABLE OF
PRODUCING DMGG WNDS/MARGINAL HAIL WILL BE POSSIBLE AND THUS WILL
CONTINUE TO HIGHLIGHT AN ELEVATED SVR WX THREAT IN THE HWO FOR
WEDNESDAY. BETTER FORCING PORTENDS HIGHER POPS RANGING FROM THE
MED-HIGH CHC RANGE IN THE SE TO LOW LKLYS IN THE NW. SHOWERS/TSTMS
MAY PERSIST AFTER DARK INTO WED NGT.

MAX TEMPS WILL LIKELY BE 3-5F LOWER THAN TUESDAY...BUT STILL AROUND
12F ABOVE NORMAL.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
THE UPPER RIDGE WILL BREAK DOWN AS A TROUGH DEEPENS INTO THE GREAT
LAKES REGION BY THURSDAY AFTERNOON. THIS WILL CORRESPOND WITH A
FRONT MOVING THROUGH THE NORTHEAST THURSDAY. TIMING FOR THIS FRONT
IS STILL VARYING BUT CURRENT EC BRINGS THE FRONT THROUGH MIDDAY
THURSDAY. COUPLE THIS FRONT WITH DAYTIME HEATING AND STRONG
SOUTHWEST FLOW...THURSDAY COULD BE THE BEST DAY FOR DAYTIME
CONVECTION THIS WEEK. BOTH THE OPERATIONAL GFS AND THE ECMWF CONTINUE
TO OUTPUT THE POSSIBILITY OF A LOW LEVEL JET THURSDAY
AFTERNOON...WHICH WITH 35-40KTS OF DEEP-LAYER SHEAR WILL ONLY
INCREASE PROBABILITIES FOR PRECIPITATION THURSDAY AFTERNOON. THIS
EASTERN NORTH AMERICA TROUGH AXIS EXTENDING FROM JAMES BAY SWD
THRU THE GRT LKS/MID- SOUTH TO THE CENTRAL GULF COAST WILL PUSH
SLOWLY EWD AND SHOULD REACH THE EAST COAST BY 00Z SAT. THIS WILL
ALLOW FOR PERSISTENT INSTABILITY OVER THE AREA THROUGH THE END OF
THE WEEK...WITH COLD NORTHWESTERLY FLOW BEHIND THE FRONT. THE
GUIDANCE IS SHOWING SOME NOTABLE DIFFS WITH THE H5 SYSTEM. THE
NAM/GFS/GEFS ARE SLOWER AND SHARPER WITH TROUGH AS IT CROSSES THE
OH VLY INTO THE MID- ATLC. THE 00Z GFS EVEN CLOSES OFF THE H5 LOW
OVER NRN VA FRI EVE. THE LAST TWO RUNS OF THE CMC HAVE BEEN TRYING
TO GENERATE A TROPICAL CYCLONE- LIKE SYSTEM NEAR THE OUTER BANKS.
THE KNOWN SLOW/TROPICAL BIASES OF THE NAM/CMC AND STRONG/CLOSED
SOLN OF THE GFS LEADS TO A UKMET/ECMWF PREFERRED SOLN WHICH FAVORS
MORE EWD PROGRESSION WITH THE TROUGH AND ITS ASSOCD COLD FRONT.

BEHIND THE DEPARTING COLD FRONT...A STG AND LARGE ANTICYCLONE
SHOULD DOMINATE PATTERN IN THE FRI-MON TIMEFRAME...BUILDING SEWD
FROM NUNAVUT CANADA ACROSS THE GRT LKS INTO THE NORTHEAST. AN
UNSEASONABLY COLD/DRY AIRMASS WILL ACCOMPANY THE HIGH RESULTING IN
BELOW NORMAL TEMPS FOR MEMORIAL DAY WEEKEND. ECENS MOS DATA SHOWS
TEMPS ON FRI/SAT STRUGGLING TO CRACK THE 60F MARK LOCALLY...WITH
SEVERAL OPPORTUNITIES FOR A LATE-SEASON FROST OVER THE NRN MTNS
SAT/SUN/MON MORNINGS. HOWEVER CURRENT LOW TEMPS REMAIN ABOVE 40
FOR MOST OF THE REGION WITH THE EXCEPTION BEING ALONG THE NEW YORK
BORDER. WINDS SHOULD REMAIN GUSTY SATURDAY MORNING. THE BETTER
CHANCE FOR FROST WILL BE SUNDAY MORNING...TEMPERATURES WILL BE
SLIGHTLY WARMER BUT THE WINDS SHOULD BE LIGHT TO CALM. THERE
SHOULD BE A MODERATION INTO THE MIDDLE OF NEXT WEEK WITH TEMPS
GETTING BACK TO NEAR NORMAL AROUND 5/28.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
MAIN FRONT AND ACTION ACROSS NY STATE...TOOK MENTION OF SHOWERS
AND STORMS OUT OF ALL SITES BUT BFD. LEFT VCSH IN BFD UNTIL 03Z.

SOME FOG LATER...BASED MAINLY ON WHAT WENT ON LAST NIGHT.

NOT SEEING MUCH DIFFERENCE FOR WED...VERY SIMILAR TO TODAY...
WILL BE IN THE WARM SECTOR...WITH NOT MUCH GOING ON.

MORE IN THE WAY OF WIDESPREAD SHOWERS AND STORMS LATER THU
INTO THU NIGHT. COULD BY BUSY ACROSS THE FAR SE THU NIGHT...
IF A WAVE FORMS ON THE FRONT.

COOLER AND BREEZY FOR FRIDAY INTO SUNDAY...AS A STRONG COLD
FRONT DROPS SE OF PA.

HO
.OUTLOOK...
THU...SCT THUNDERSTORM IMPACTS POSSIBLE...MAINLY IN THE PM.
FRI-MON...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...LAMBERT/STEINBUGL
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...LAMBERT/STEINBUGL
LONG TERM...CERU/STEINBUGL
AVIATION...LAMBERT/MARTIN

000
FXUS61 KCTP 212325
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
725 PM EDT TUE MAY 21 2013

.SYNOPSIS...
A WARM AND HUMID...SUMMERTIME AIRMASS WILL CONTINUE TO BRING WELL
ABOVE NORMAL TEMPERATURES TO CENTRAL PENNSYLVANIA LATE TODAY THROUGH
WEDNESDAY. A COLD FRONT WILL CROSS THE REGION ON THURSDAY. A LARGE
AREA OF HIGH PRESSURE WILL BUILD SOUTHEAST FROM CENTRAL CANADA INTO
THE NORTHEAST AND MID-ATLANTIC STATES. THIS HIGH WILL BRING COOLER
AND DRIER AIR TO THE AREA FOR MEMORIAL DAY WEEKEND...THAT COULD
LAST RIGHT THROUGH MONDAY.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
EARLY AFTERNOON VISIBLE SATELLITE LOOP SHOWS CU FIELD GRADUALLY
EXPANDING EAST FROM THE ALLEGHENY PLATEAU OF NORTHERN AND WRN PENN
AND BEGINNING TO GROW A BIT VERTICALLY.

THE LIMITING FACTORS TO EXPLOSIVE TSRA DEVELOPMENT SO FAR IN THE
HIGHLY UNSTABLE AIRMASS AT LLVLS HAS BEEN THE WSWRLY AND BROADLY
DIFFLUENT FLOW WITHIN THE 925-850 MB LAYER...BENEATH A LARGE POOL OF
QUITE WARM AIR /+7-8C AT 700 MB/...AND WEAK RIDGING ALOFT. THIS WILL
SERVE TO LIMIT CONVECTION ACROSS THE CWA THROUGH 20-21Z.

HIGH RESOLUTION 12-17Z MODEL GUIDANCE CONTINUES TO DEVELOP VERY
ROBUST...LATE DAY ML CAPE OF OVER 2000 J/KG WITHIN THE AREA OF MOST
ABUNDANT SUNSHINE SO FAR THIS AFTERNOON. AS THE RATHER FLAT RIDGING
SLIDES JUST EAST OF THE AREA LATER TODAY...A FAIRLY WELL-DEFINED LEE
TROUGH SHOULD FORM EAST OF THE ALLEGHENY FRONT AND PROVIDE ENOUGH
LLVL CONVERGENCE /IN CONCERT WITH SLIGHT COOLING ALOFT ARRIVING FROM
THE WEST/ TO SPARK ISOLATED TO SCATTERED STRONG TO POTENTIALLY
TSRA. SINCE THE LAST AFD...SPC HAS GREATLY EXPANDED THEIR DY1 SLIGHT
RISK AREA TO ENCOMPASS ABOUT THE NWRN TWO-THIRDS OF PENN...WITH SVR
TSRA WATCH 203 RECENTLY POSTED ISSUED FOR MUCH OF NEW YORK...RIGHT
AGAINST THE ENTIRE PA/NY BORDER.

SREF PROP OF CAPE EXCEEDING 1200 J/KG IS PEGGED BETWEEN AT 100
PERCENT FOR ALL BUT THE EXTREME SERN ZONES BETWEEN 20-23Z TODAY.

NAM HAS BEEN WOBBLING EAST AND WEST A BIT WITH IT/S DEPICTION OF THE
AXIS OF RELATIVELY HIGH EHI. 00-06Z RUNS WERE A BIT FURTHER EAST
ACROSS THE SUSQ VALLEY WITH VALUES AROUND 1.5 M2/S2...WHILE THE
FRESH 12Z RUN IS PAINTING A WIDE STRIPE OF MORE OMINOUS 2-2.5 MS/S2
EHI CENTERED ON A LINE FROM NEAR KELM...TO KUNV AND KAOO BY 00Z WED.

THIS TYPE OF EHI...WITH PRECEDING ABUNDANT INSOLATION IS QUITE
INFREQUENT IN THIS NECK OF THE WOODS. TYPICALLY...MORE PRONOUNCED
SHEAR AND FORCING HERE IN CENTRAL PENN USUALLY RESULTS IN MORE EARLY
DAY CONVECTION /OR STRATIFORM PRECIP/ WHICH LATER LIMITS THE DEGREE
OF LLVL-BASED INSTABILITY.

THE STRENGTHENING SWRLY FLOW AT 850 MB /TO AROUND 30 KTS LATE TODAY/
IS THE MOST CONCERNING FOR THE SEVERE THREAT ACROSS THE CENTRAL
RIDGE AND VALLEY REGION. IF WE CAN GET CONVECTION TO INITIATE WITHIN
THIS HIGHLY PRIMED/UNSTABLE ATMOS...STORMS COULD EASILY BECOME VERY
TALL AND LOCALLY SEVERE.

WEAK HT FALLS WILL DEVELOP IN ASSOCIATION WITH A S/W CRESTING THE
UPPER RIDGE OVER THE UPPER GRT LKS...AND NOSE OF STG LLJ WILL MOVE
NE INTO THE THE UPPER OH VLY/NW PA BY 00Z WED. THE MODELS SHOW A
MCS WITH THIS FEATURE MOVG EWD ACRS THE ERN GRT LKS/ST. LAWRENCE VLY
INTO NRN NEW ENGLAND. HIGHEST POPS OVERNIGHT ARE ACRS THE NRN
TIER...WITH NWD DISPLACEMENT MDL BIAS ARGUING FOR A MORE SRN MCS
TRACK. IN ADDITION...A LINGERING...NEARLY NORTH/SOUTH RIBBON OF HIGH
ML CAPE ACROSS THE SUSQ VALLEY COULD SUPPORT CONTINUED SCATTERED
SHRA/TSRA THERE THROUGH ABOUT 06Z WED.

THE SOUTHWEST LLVL FLOW WILL CONTINUE TO ADVECT VERY WARM AND MOIST
AIR INTO THE REGION WITH MID TO LATE AFTERNOON TEMPS TOPPING OUT
WELL INTO THE 80S ACROSS THE VALLEYS OF CENTRAL AND SRN PENN...AND
SFC DEWPOINTS IN THE LOWER TO MID 60S. MAX TEMPS ACROSS THE MTNS
WILL BE 80-84F.

CONVECTION WILL GRADUALLY DIMINISH LATE TONIGHT WITH WIND BECOMING
LIGHT IN THE MUGGY AIRMASS. PATCHY 1-2SM FOG WILL FORM AFTER
07Z...AND COULD BE LOCALLY DENSE IN THE VALLEYS WHERE RAINFALL
OCCURS.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
A S/W MOVG EWD ACRS THE UPPER MS VLY INVOF IA WILL PHASE WITH A
CANADIAN UPPER LOW/TROUGH DROPPING SWD ACRS HUDSON/JAMES BAY DURING
THE DAY WEDNESDAY...REACHING THE MIDWEST BY F48. AT THE SFC...A
COLD FRONT PUSHING EWD THRU THE OH VLY WILL BE THE MAIN FOCUS FOR
TSTM DEVELOPMENT/SVR POTENTIAL THIS PERIOD.

AM CLOUDS WITH SOME SPOTTY SHOWERS AND AREAS OF 1-2SM FIG WILL
COMBINE WITH WEAK RIDGING WITHIN THE PREDOMINANT SWRLY FLOW
ALOFT...TO LIMIT DIURNAL HEATING TO SOME EXTENT ACRS THE DAY 2 SPC
SLGT RISK AREA - WHICH COVERS NEARLY ALL OF THE CWA WITH THE
EXCEPTION OF THE FAR SERN ZONES. ALTHOUGH LOW TO MID LEVEL WINDS
WILL BE STRONGEST ACROSS THE NW HALF OF PENN...LATEST SREF AND SHORT
RANGE MODEL GUIDANCE PAINTS THE GREATEST PROBABILITY FOR CAPE
GREATER THAN 1200 J/KG ACROSS THE LOWER SUSQ VALLEY LATE WEDNESDAY
AFTERNOON.

DESPITE THE TEMPERED DESTABILIZATION...EXPECT AN AFTN INCREASE IN
TSTM COVERAGE /WITH LOWER CLOUD BASES COMPARED TO TUESDAY`S/ ALONG
WITH SOME PICK-UP IN INTENSITY AS BELT OF STRONGER FLOW ALOFT SHIFTS
EWD AHEAD OF THE MID-UPPER TROUGH. BANDS OF TSTMS CAPABLE OF
PRODUCING DMGG WNDS/MARGINAL HAIL WILL BE POSSIBLE AND THUS WILL
CONTINUE TO HIGHLIGHT AN ELEVATED SVR WX THREAT IN THE HWO FOR
WEDNESDAY. BETTER FORCING PORTENDS HIGHER POPS RANGING FROM THE
MED-HIGH CHC RANGE IN THE SE TO LOW LKLYS IN THE NW. SHOWERS/TSTMS
MAY PERSIST AFTER DARK INTO WED NGT.

MAX TEMPS WILL LIKELY BE 3-5F LOWER THAN TUESDAY...BUT STILL AROUND
12F ABOVE NORMAL.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
THE UPPER RIDGE WILL BREAK DOWN AS A TROUGH DEEPENS INTO THE GREAT
LAKES REGION BY THURSDAY AFTERNOON. THIS WILL CORRESPOND WITH A
FRONT MOVING THROUGH THE NORTHEAST THURSDAY. TIMING FOR THIS FRONT
IS STILL VARYING BUT CURRENT EC BRINGS THE FRONT THROUGH MIDDAY
THURSDAY. COUPLE THIS FRONT WITH DAYTIME HEATING AND STRONG
SOUTHWEST FLOW...THURSDAY COULD BE THE BEST DAY FOR DAYTIME
CONVECTION THIS WEEK. BOTH THE OPERATIONAL GFS AND THE ECMWF CONTINUE
TO OUTPUT THE POSSIBILITY OF A LOW LEVEL JET THURSDAY
AFTERNOON...WHICH WITH 35-40KTS OF DEEP-LAYER SHEAR WILL ONLY
INCREASE PROBABILITIES FOR PRECIPITATION THURSDAY AFTERNOON. THIS
EASTERN NORTH AMERICA TROUGH AXIS EXTENDING FROM JAMES BAY SWD
THRU THE GRT LKS/MID- SOUTH TO THE CENTRAL GULF COAST WILL PUSH
SLOWLY EWD AND SHOULD REACH THE EAST COAST BY 00Z SAT. THIS WILL
ALLOW FOR PERSISTENT INSTABILITY OVER THE AREA THROUGH THE END OF
THE WEEK...WITH COLD NORTHWESTERLY FLOW BEHIND THE FRONT. THE
GUIDANCE IS SHOWING SOME NOTABLE DIFFS WITH THE H5 SYSTEM. THE
NAM/GFS/GEFS ARE SLOWER AND SHARPER WITH TROUGH AS IT CROSSES THE
OH VLY INTO THE MID- ATLC. THE 00Z GFS EVEN CLOSES OFF THE H5 LOW
OVER NRN VA FRI EVE. THE LAST TWO RUNS OF THE CMC HAVE BEEN TRYING
TO GENERATE A TROPICAL CYCLONE- LIKE SYSTEM NEAR THE OUTER BANKS.
THE KNOWN SLOW/TROPICAL BIASES OF THE NAM/CMC AND STRONG/CLOSED
SOLN OF THE GFS LEADS TO A UKMET/ECMWF PREFERRED SOLN WHICH FAVORS
MORE EWD PROGRESSION WITH THE TROUGH AND ITS ASSOCD COLD FRONT.

BEHIND THE DEPARTING COLD FRONT...A STG AND LARGE ANTICYCLONE
SHOULD DOMINATE PATTERN IN THE FRI-MON TIMEFRAME...BUILDING SEWD
FROM NUNAVUT CANADA ACROSS THE GRT LKS INTO THE NORTHEAST. AN
UNSEASONABLY COLD/DRY AIRMASS WILL ACCOMPANY THE HIGH RESULTING IN
BELOW NORMAL TEMPS FOR MEMORIAL DAY WEEKEND. ECENS MOS DATA SHOWS
TEMPS ON FRI/SAT STRUGGLING TO CRACK THE 60F MARK LOCALLY...WITH
SEVERAL OPPORTUNITIES FOR A LATE-SEASON FROST OVER THE NRN MTNS
SAT/SUN/MON MORNINGS. HOWEVER CURRENT LOW TEMPS REMAIN ABOVE 40
FOR MOST OF THE REGION WITH THE EXCEPTION BEING ALONG THE NEW YORK
BORDER. WINDS SHOULD REMAIN GUSTY SATURDAY MORNING. THE BETTER
CHANCE FOR FROST WILL BE SUNDAY MORNING...TEMPERATURES WILL BE
SLIGHTLY WARMER BUT THE WINDS SHOULD BE LIGHT TO CALM. THERE
SHOULD BE A MODERATION INTO THE MIDDLE OF NEXT WEEK WITH TEMPS
GETTING BACK TO NEAR NORMAL AROUND 5/28.

&&

.AVIATION /23Z TUESDAY THROUGH SUNDAY/...
MAIN FRONT AND ACTION ACROSS NY STATE...TOOK MENTION OF SHOWERS
AND STORMS OUT OF ALL SITES BUT BFD. LEFT VCSH IN BFD UNTIL 03Z.

SOME FOG LATER...BASED MAINLY ON WHAT WENT ON LAST NIGHT.

NOT SEEING MUCH DIFFERENCE FOR WED...VERY SIMILAR TO TODAY...
WILL BE IN THE WARM SECTOR...WITH NOT MUCH GOING ON.

MORE IN THE WAY OF WIDESPREAD SHOWERS AND STORMS LATER THU
INTO THU NIGHT. COULD BY BUSY ACROSS THE FAR SE THU NIGHT...
IF A WAVE FORMS ON THE FRONT.

COOLER AND BREEZY FOR FRIDAY INTO SUNDAY...AS A STRONG COLD
FRONT DROPS SE OF PA.

HO
.OUTLOOK...
THU...SCT THUNDERSTORM IMPACTS POSSIBLE...MAINLY IN THE PM.
FRI-MON...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...LAMBERT/STEINBUGL
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT/STEINBUGL
LONG TERM...CERU/STEINBUGL
AVIATION...LAMBERT/MARTIN

000
FXUS61 KCTP 212130
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
530 PM EDT TUE MAY 21 2013

.SYNOPSIS...
A WARM AND HUMID...SUMMERTIME AIRMASS WILL CONTINUE TO BRING WELL
ABOVE NORMAL TEMPERATURES TO CENTRAL PENNSYLVANIA LATE TODAY THROUGH
WEDNESDAY. A COLD FRONT WILL CROSS THE REGION ON THURSDAY. A LARGE
AREA OF HIGH PRESSURE WILL BUILD SOUTHEAST FROM CENTRAL CANADA INTO
THE NORTHEAST AND MID-ATLANTIC STATES. THIS HIGH WILL BRING COOLER
AND DRIER AIR TO THE AREA FOR MEMORIAL DAY WEEKEND...THAT COULD
LAST RIGHT THROUGH MONDAY.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
EARLY AFTERNOON VISIBLE SATELLITE LOOP SHOWS CU FIELD GRADUALLY
EXPANDING EAST FROM THE ALLEGHENY PLATEAU OF NORTHERN AND WRN PENN
AND BEGINNING TO GROW A BIT VERTICALLY.

THE LIMITING FACTORS TO EXPLOSIVE TSRA DEVELOPMENT SO FAR IN THE
HIGHLY UNSTABLE AIRMASS AT LLVLS HAS BEEN THE WSWRLY AND BROADLY
DIFFLUENT FLOW WITHIN THE 925-850 MB LAYER...BENEATH A LARGE POOL OF
QUITE WARM AIR /+7-8C AT 700 MB/...AND WEAK RIDGING ALOFT. THIS WILL
SERVE TO LIMIT CONVECTION ACROSS THE CWA THROUGH 20-21Z.

HIGH RESOLUTION 12-17Z MODEL GUIDANCE CONTINUES TO DEVELOP VERY
ROBUST...LATE DAY ML CAPE OF OVER 2000 J/KG WITHIN THE AREA OF MOST
ABUNDANT SUNSHINE SO FAR THIS AFTERNOON. AS THE RATHER FLAT RIDGING
SLIDES JUST EAST OF THE AREA LATER TODAY...A FAIRLY WELL-DEFINED LEE
TROUGH SHOULD FORM EAST OF THE ALLEGHENY FRONT AND PROVIDE ENOUGH
LLVL CONVERGENCE /IN CONCERT WITH SLIGHT COOLING ALOFT ARRIVING FROM
THE WEST/ TO SPARK ISOLATED TO SCATTERED STRONG TO POTENTIALLY
TSRA. SINCE THE LAST AFD...SPC HAS GREATLY EXPANDED THEIR DY1 SLIGHT
RISK AREA TO ENCOMPASS ABOUT THE NWRN TWO-THIRDS OF PENN...WITH SVR
TSRA WATCH 203 RECENTLY POSTED ISSUED FOR MUCH OF NEW YORK...RIGHT
AGAINST THE ENTIRE PA/NY BORDER.

SREF PROP OF CAPE EXCEEDING 1200 J/KG IS PEGGED BETWEEN AT 100
PERCENT FOR ALL BUT THE EXTREME SERN ZONES BETWEEN 20-23Z TODAY.

NAM HAS BEEN WOBBLING EAST AND WEST A BIT WITH IT/S DEPICTION OF THE
AXIS OF RELATIVELY HIGH EHI. 00-06Z RUNS WERE A BIT FURTHER EAST
ACROSS THE SUSQ VALLEY WITH VALUES AROUND 1.5 M2/S2...WHILE THE
FRESH 12Z RUN IS PAINTING A WIDE STRIPE OF MORE OMINOUS 2-2.5 MS/S2
EHI CENTERED ON A LINE FROM NEAR KELM...TO KUNV AND KAOO BY 00Z WED.

THIS TYPE OF EHI...WITH PRECEDING ABUNDANT INSOLATION IS QUITE
INFREQUENT IN THIS NECK OF THE WOODS. TYPICALLY...MORE PRONOUNCED
SHEAR AND FORCING HERE IN CENTRAL PENN USUALLY RESULTS IN MORE EARLY
DAY CONVECTION /OR STRATIFORM PRECIP/ WHICH LATER LIMITS THE DEGREE
OF LLVL-BASED INSTABILITY.

THE STRENGTHENING SWRLY FLOW AT 850 MB /TO AROUND 30 KTS LATE TODAY/
IS THE MOST CONCERNING FOR THE SEVERE THREAT ACROSS THE CENTRAL
RIDGE AND VALLEY REGION. IF WE CAN GET CONVECTION TO INITIATE WITHIN
THIS HIGHLY PRIMED/UNSTABLE ATMOS...STORMS COULD EASILY BECOME VERY
TALL AND LOCALLY SEVERE.

WEAK HT FALLS WILL DEVELOP IN ASSOCIATION WITH A S/W CRESTING THE
UPPER RIDGE OVER THE UPPER GRT LKS...AND NOSE OF STG LLJ WILL MOVE
NE INTO THE THE UPPER OH VLY/NW PA BY 00Z WED. THE MODELS SHOW A
MCS WITH THIS FEATURE MOVG EWD ACRS THE ERN GRT LKS/ST. LAWRENCE VLY
INTO NRN NEW ENGLAND. HIGHEST POPS OVERNIGHT ARE ACRS THE NRN
TIER...WITH NWD DISPLACEMENT MDL BIAS ARGUING FOR A MORE SRN MCS
TRACK. IN ADDITION...A LINGERING...NEARLY NORTH/SOUTH RIBBON OF HIGH
ML CAPE ACROSS THE SUSQ VALLEY COULD SUPPORT CONTINUED SCATTERED
SHRA/TSRA THERE THROUGH ABOUT 06Z WED.

THE SOUTHWEST LLVL FLOW WILL CONTINUE TO ADVECT VERY WARM AND MOIST
AIR INTO THE REGION WITH MID TO LATE AFTERNOON TEMPS TOPPING OUT
WELL INTO THE 80S ACROSS THE VALLEYS OF CENTRAL AND SRN PENN...AND
SFC DEWPOINTS IN THE LOWER TO MID 60S. MAX TEMPS ACROSS THE MTNS
WILL BE 80-84F.

CONVECTION WILL GRADUALLY DIMINISH LATE TONIGHT WITH WIND BECOMING
LIGHT IN THE MUGGY AIRMASS. PATCHY 1-2SM FOG WILL FORM AFTER
07Z...AND COULD BE LOCALLY DENSE IN THE VALLEYS WHERE RAINFALL
OCCURS.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
A S/W MOVG EWD ACRS THE UPPER MS VLY INVOF IA WILL PHASE WITH A
CANADIAN UPPER LOW/TROUGH DROPPING SWD ACRS HUDSON/JAMES BAY DURING
THE DAY WEDNESDAY...REACHING THE MIDWEST BY F48. AT THE SFC...A
COLD FRONT PUSHING EWD THRU THE OH VLY WILL BE THE MAIN FOCUS FOR
TSTM DEVELOPMENT/SVR POTENTIAL THIS PERIOD.

AM CLOUDS WITH SOME SPOTTY SHOWERS AND AREAS OF 1-2SM FIG WILL
COMBINE WITH WEAK RIDGING WITHIN THE PREDOMINANT SWRLY FLOW
ALOFT...TO LIMIT DIURNAL HEATING TO SOME EXTENT ACRS THE DAY 2 SPC
SLGT RISK AREA - WHICH COVERS NEARLY ALL OF THE CWA WITH THE
EXCEPTION OF THE FAR SERN ZONES. ALTHOUGH LOW TO MID LEVEL WINDS
WILL BE STRONGEST ACROSS THE NW HALF OF PENN...LATEST SREF AND SHORT
RANGE MODEL GUIDANCE PAINTS THE GREATEST PROBABILITY FOR CAPE
GREATER THAN 1200 J/KG ACROSS THE LOWER SUSQ VALLEY LATE WEDNESDAY
AFTERNOON.

DESPITE THE TEMPERED DESTABILIZATION...EXPECT AN AFTN INCREASE IN
TSTM COVERAGE /WITH LOWER CLOUD BASES COMPARED TO TUESDAY`S/ ALONG
WITH SOME PICK-UP IN INTENSITY AS BELT OF STRONGER FLOW ALOFT SHIFTS
EWD AHEAD OF THE MID-UPPER TROUGH. BANDS OF TSTMS CAPABLE OF
PRODUCING DMGG WNDS/MARGINAL HAIL WILL BE POSSIBLE AND THUS WILL
CONTINUE TO HIGHLIGHT AN ELEVATED SVR WX THREAT IN THE HWO FOR
WEDNESDAY. BETTER FORCING PORTENDS HIGHER POPS RANGING FROM THE
MED-HIGH CHC RANGE IN THE SE TO LOW LKLYS IN THE NW. SHOWERS/TSTMS
MAY PERSIST AFTER DARK INTO WED NGT.

MAX TEMPS WILL LIKELY BE 3-5F LOWER THAN TUESDAY...BUT STILL AROUND
12F ABOVE NORMAL.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
THE UPPER RIDGE WILL BREAK DOWN AS A TROUGH DEEPENS INTO THE GREAT
LAKES REGION BY THURSDAY AFTERNOON. THIS WILL CORRESPOND WITH A
FRONT MOVING THROUGH THE NORTHEAST THURSDAY. TIMING FOR THIS FRONT
IS STILL VARYING BUT CURRENT EC BRINGS THE FRONT THROUGH MIDDAY
THURSDAY. COUPLE THIS FRONT WITH DAYTIME HEATING AND STRONG
SOUTHWEST FLOW...THURSDAY COULD BE THE BEST DAY FOR DAYTIME
CONVECTION THIS WEEK. BOTH THE OPERATIONAL GFS AND THE ECMWF CONTINUE
TO OUTPUT THE POSSIBILITY OF A LOW LEVEL JET THURSDAY
AFTERNOON...WHICH WITH 35-40KTS OF DEEP-LAYER SHEAR WILL ONLY
INCREASE PROBABILITIES FOR PRECIPITATION THURSDAY AFTERNOON. THIS
EASTERN NORTH AMERICA TROUGH AXIS EXTENDING FROM JAMES BAY SWD
THRU THE GRT LKS/MID- SOUTH TO THE CENTRAL GULF COAST WILL PUSH
SLOWLY EWD AND SHOULD REACH THE EAST COAST BY 00Z SAT. THIS WILL
ALLOW FOR PERSISTENT INSTABILITY OVER THE AREA THROUGH THE END OF
THE WEEK...WITH COLD NORTHWESTERLY FLOW BEHIND THE FRONT. THE
GUIDANCE IS SHOWING SOME NOTABLE DIFFS WITH THE H5 SYSTEM. THE
NAM/GFS/GEFS ARE SLOWER AND SHARPER WITH TROUGH AS IT CROSSES THE
OH VLY INTO THE MID- ATLC. THE 00Z GFS EVEN CLOSES OFF THE H5 LOW
OVER NRN VA FRI EVE. THE LAST TWO RUNS OF THE CMC HAVE BEEN TRYING
TO GENERATE A TROPICAL CYCLONE- LIKE SYSTEM NEAR THE OUTER BANKS.
THE KNOWN SLOW/TROPICAL BIASES OF THE NAM/CMC AND STRONG/CLOSED
SOLN OF THE GFS LEADS TO A UKMET/ECMWF PREFERRED SOLN WHICH FAVORS
MORE EWD PROGRESSION WITH THE TROUGH AND ITS ASSOCD COLD FRONT.

BEHIND THE DEPARTING COLD FRONT...A STG AND LARGE ANTICYCLONE
SHOULD DOMINATE PATTERN IN THE FRI-MON TIMEFRAME...BUILDING SEWD
FROM NUNAVUT CANADA ACROSS THE GRT LKS INTO THE NORTHEAST. AN
UNSEASONABLY COLD/DRY AIRMASS WILL ACCOMPANY THE HIGH RESULTING IN
BELOW NORMAL TEMPS FOR MEMORIAL DAY WEEKEND. ECENS MOS DATA SHOWS
TEMPS ON FRI/SAT STRUGGLING TO CRACK THE 60F MARK LOCALLY...WITH
SEVERAL OPPORTUNITIES FOR A LATE-SEASON FROST OVER THE NRN MTNS
SAT/SUN/MON MORNINGS. HOWEVER CURRENT LOW TEMPS REMAIN ABOVE 40
FOR MOST OF THE REGION WITH THE EXCEPTION BEING ALONG THE NEW YORK
BORDER. WINDS SHOULD REMAIN GUSTY SATURDAY MORNING. THE BETTER
CHANCE FOR FROST WILL BE SUNDAY MORNING...TEMPERATURES WILL BE
SLIGHTLY WARMER BUT THE WINDS SHOULD BE LIGHT TO CALM. THERE
SHOULD BE A MODERATION INTO THE MIDDLE OF NEXT WEEK WITH TEMPS
GETTING BACK TO NEAR NORMAL AROUND 5/28.

&&

.AVIATION /22Z TUESDAY THROUGH SUNDAY/...
DID ADJUST 21Z TAF PACKAGE SOME TO CUT BACK THE MENTION OF
THUNDER. MAIN CHANCE WILL BE NEAR THE NY BORDER THIS EVENING...
FURTHER SOUTH IT IS WARMER ALOFT WITH LOWER DEWPOINTS.

WILL CONTINUE TO ADJUST THIS EVENING AS NEEDED.

EARLIER DISCUSSION BELOW.

ALL CENTRAL PA TAF SITES WILL STAY PRIMARILY VFR THROUGH AT LEAST
EARLY THIS EVENING.

HOWEVER...SCT LATE PM TSRA WILL BE AN AVIATION CONCERN. THE BEST CHC
OF TSRA AND ACCOMPANYING BRIEF VSBY REDUCTION/GUSTY WINDS WILL BE
ACROSS THE CENTRAL RIDGE AND VALLEY REGION AND POINTS NORTH TWD THE
NEW YORK BORDER. LATEST MDL DATA CONTINUES TO INDICATE SOME
POSSIBILITY OF A BKN LINE OF TSRA DEVELOPING SOMEWHERE NEAR THE
I-99/RT 220 CORRIDOR FROM KJST/KAOO...NE TO KIPT...THEN SWEEPING SE
ACROSS CENTRAL PENN AND TWD THE SUSQ VALLEY THIS EVENING.

CONVECTIVE SHOWERS AND ISOLATED-SCT TSRA WILL DIMINISH AFTER 06Z
WITH MVFR HAZE LOWERING TO AREAS OF IFR STRATUS AND FOG THROUGH 12
OR 13Z WED. MAINLY VFR TO HIGH END MVFR LATER WEDNESDAY MORNING INTO
THE EARLY AFTERNOON BEFORE MORE SHOWERS AND TSRA DEVELOP ACROSS
CENTRAL PENN IN THE 18Z-23Z WINDOW.

.OUTLOOK...
THU...SCT THUNDERSTORM IMPACTS POSSIBLE...MAINLY IN THE PM.
FRI-MON...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...LAMBERT/STEINBUGL
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT/STEINBUGL
LONG TERM...CERU/STEINBUGL
AVIATION...LAMBERT/MARTIN

000
FXUS61 KCTP 212005
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
405 PM EDT TUE MAY 21 2013

.SYNOPSIS...
A WARM AND HUMID...SUMMERTIME AIRMASS WILL CONTINUE TO BRING WELL
ABOVE NORMAL TEMPERATURES TO CENTRAL PENNSYLVANIA LATE TODAY THROUGH
WEDNESDAY. A COLD FRONT WILL CROSS THE REGION ON THURSDAY. A LARGE
AREA OF HIGH PRESSURE WILL BUILD SOUTHEAST FROM CENTRAL CANADA INTO
THE NORTHEAST AND MID-ATLANTIC STATES. THIS HIGH WILL BRING COOLER
AND DRIER AIR TO THE AREA FOR MEMORIAL DAY WEEKEND...THAT COULD
LAST RIGHT THROUGH MONDAY.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
EARLY AFTERNOON VISIBLE SATELLITE LOOP SHOWS CU FIELD GRADUALLY
EXPANDING EAST FROM THE ALLEGHENY PLATEAU OF NORTHERN AND WRN PENN
AND BEGINNING TO GROW A BIT VERTICALLY.

THE LIMITING FACTORS TO EXPLOSIVE TSRA DEVELOPMENT SO FAR IN THE
HIGHLY UNSTABLE AIRMASS AT LLVLS HAS BEEN THE WSWRLY AND BROADLY
DIFFLUENT FLOW WITHIN THE 925-850 MB LAYER...BENEATH A LARGE POOL OF
QUITE WARM AIR /+7-8C AT 700 MB/...AND WEAK RIDGING ALOFT. THIS WILL
SERVE TO LIMIT CONVECTION ACROSS THE CWA THROUGH 20-21Z.

HIGH RESOLUTION 12-17Z MODEL GUIDANCE CONTINUES TO DEVELOP VERY
ROBUST...LATE DAY ML CAPE OF OVER 2000 J/KG WITHIN THE AREA OF MOST
ABUNDANT SUNSHINE SO FAR THIS AFTERNOON. AS THE RATHER FLAT RIDGING
SLIDES JUST EAST OF THE AREA LATER TODAY...A FAIRLY WELL-DEFINED LEE
TROUGH SHOULD FORM EAST OF THE ALLEGHENY FRONT AND PROVIDE ENOUGH
LLVL CONVERGENCE /IN CONCERT WITH SLIGHT COOLING ALOFT ARRIVING FROM
THE WEST/ TO SPARK ISOLATED TO SCATTERED STRONG TO POTENTIALLY
TSRA. SINCE THE LAST AFD...SPC HAS GREATLY EXPANDED THEIR DY1 SLIGHT
RISK AREA TO ENCOMPASS ABOUT THE NWRN TWO-THIRDS OF PENN...WITH SVR
TSRA WATCH 203 RECENTLY POSTED ISSUED FOR MUCH OF NEW YORK...RIGHT
AGAINST THE ENTIRE PA/NY BORDER.

SREF PROP OF CAPE EXCEEDING 1200 J/KG IS PEGGED BETWEEN AT 100
PERCENT FOR ALL BUT THE EXTREME SERN ZONES BETWEEN 20-23Z TODAY.

NAM HAS BEEN WOBBLING EAST AND WEST A BIT WITH IT/S DEPICTION OF THE
AXIS OF RELATIVELY HIGH EHI. 00-06Z RUNS WERE A BIT FURTHER EAST
ACROSS THE SUSQ VALLEY WITH VALUES AROUND 1.5 M2/S2...WHILE THE
FRESH 12Z RUN IS PAINTING A WIDE STRIPE OF MORE OMINOUS 2-2.5 MS/S2
EHI CENTERED ON A LINE FROM NEAR KELM...TO KUNV AND KAOO BY 00Z WED.

THIS TYPE OF EHI...WITH PRECEDING ABUNDANT INSOLATION IS QUITE
INFREQUENT IN THIS NECK OF THE WOODS. TYPICALLY...MORE PRONOUNCED
SHEAR AND FORCING HERE IN CENTRAL PENN USUALLY RESULTS IN MORE EARLY
DAY CONVECTION /OR STRATIFORM PRECIP/ WHICH LATER LIMITS THE DEGREE
OF LLVL-BASED INSTABILITY.

THE STRENGTHENING SWRLY FLOW AT 850 MB /TO AROUND 30 KTS LATE TODAY/
IS THE MOST CONCERNING FOR THE SEVERE THREAT ACROSS THE CENTRAL
RIDGE AND VALLEY REGION. IF WE CAN GET CONVECTION TO INITIATE WITHIN
THIS HIGHLY PRIMED/UNSTABLE ATMOS...STORMS COULD EASILY BECOME VERY
TALL AND LOCALLY SEVERE.

WEAK HT FALLS WILL DEVELOP IN ASSOCIATION WITH A S/W CRESTING THE
UPPER RIDGE OVER THE UPPER GRT LKS...AND NOSE OF STG LLJ WILL MOVE
NE INTO THE THE UPPER OH VLY/NW PA BY 00Z WED. THE MODELS SHOW A
MCS WITH THIS FEATURE MOVG EWD ACRS THE ERN GRT LKS/ST. LAWRENCE VLY
INTO NRN NEW ENGLAND. HIGHEST POPS OVERNIGHT ARE ACRS THE NRN
TIER...WITH NWD DISPLACEMENT MDL BIAS ARGUING FOR A MORE SRN MCS
TRACK. IN ADDITION...A LINGERING...NEARLY NORTH/SOUTH RIBBON OF HIGH
ML CAPE ACROSS THE SUSQ VALLEY COULD SUPPORT CONTINUED SCATTERED
SHRA/TSRA THERE THROUGH ABOUT 06Z WED.

THE SOUTHWEST LLVL FLOW WILL CONTINUE TO ADVECT VERY WARM AND MOIST
AIR INTO THE REGION WITH MID TO LATE AFTERNOON TEMPS TOPPING OUT
WELL INTO THE 80S ACROSS THE VALLEYS OF CENTRAL AND SRN PENN...AND
SFC DEWPOINTS IN THE LOWER TO MID 60S. MAX TEMPS ACROSS THE MTNS
WILL BE 80-84F.

CONVECTION WILL GRADUALLY DIMINISH LATE TONIGHT WITH WIND BECOMING
LIGHT IN THE MUGGY AIRMASS. PATCHY 1-2SM FOG WILL FORM AFTER
07Z...AND COULD BE LOCALLY DENSE IN THE VALLEYS WHERE RAINFALL
OCCURS.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
A S/W MOVG EWD ACRS THE UPPER MS VLY INVOF IA WILL PHASE WITH A
CANADIAN UPPER LOW/TROUGH DROPPING SWD ACRS HUDSON/JAMES BAY DURING
THE DAY WEDNESDAY...REACHING THE MIDWEST BY F48. AT THE SFC...A
COLD FRONT PUSHING EWD THRU THE OH VLY WILL BE THE MAIN FOCUS FOR
TSTM DEVELOPMENT/SVR POTENTIAL THIS PERIOD.

AM CLOUDS WITH SOME SPOTTY SHOWERS AND AREAS OF 1-2SM FIG WILL
COMBINE WITH WEAK RIDGING WITHIN THE PREDOMINANT SWRLY FLOW
ALOFT...TO LIMIT DIURNAL HEATING TO SOME EXTENT ACRS THE DAY 2 SPC
SLGT RISK AREA - WHICH COVERS NEARLY ALL OF THE CWA WITH THE
EXCEPTION OF THE FAR SERN ZONES. ALTHOUGH LOW TO MID LEVEL WINDS
WILL BE STRONGEST ACROSS THE NW HALF OF PENN...LATEST SREF AND SHORT
RANGE MODEL GUIDANCE PAINTS THE GREATEST PROBABILITY FOR CAPE
GREATER THAN 1200 J/KG ACROSS THE LOWER SUSQ VALLEY LATE WEDNESDAY
AFTERNOON.

DESPITE THE TEMPERED DESTABILIZATION...EXPECT AN AFTN INCREASE IN
TSTM COVERAGE /WITH LOWER CLOUD BASES COMPARED TO TUESDAY`S/ ALONG
WITH SOME PICK-UP IN INTENSITY AS BELT OF STRONGER FLOW ALOFT SHIFTS
EWD AHEAD OF THE MID-UPPER TROUGH. BANDS OF TSTMS CAPABLE OF
PRODUCING DMGG WNDS/MARGINAL HAIL WILL BE POSSIBLE AND THUS WILL
CONTINUE TO HIGHLIGHT AN ELEVATED SVR WX THREAT IN THE HWO FOR
WEDNESDAY. BETTER FORCING PORTENDS HIGHER POPS RANGING FROM THE
MED-HIGH CHC RANGE IN THE SE TO LOW LKLYS IN THE NW. SHOWERS/TSTMS
MAY PERSIST AFTER DARK INTO WED NGT.

MAX TEMPS WILL LIKELY BE 3-5F LOWER THAN TUESDAY...BUT STILL AROUND
12F ABOVE NORMAL.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...

THE UPPER RIDGE WILL BREAK DOWN AS A TROUGH DEEPENS INTO THE GREAT
LAKES REGION BY THURSDAY AFTERNOON. THIS WILL CORRESPOND WITH A
FRONT MOVING THROUGH THE NORTHEAST THURSDAY. TIMING FOR THIS FRONT
IS STILL VARYING BUT CURRENT EC BRINGS THE FRONT THROUGH MIDDAY
THURSDAY. COUPLE THIS FRONT WITH DAYTIME HEATING AND STRONG
SOUTHWEST FLOW...THURSDAY COULD BE THE BEST DAY FOR DAYTIME
CONVECTION THIS WEEK. BOTH THE OPERATIONAL GFS AND THE ECMWF CONTINUE
TO OUTPUT THE POSSIBILITY OF A LOW LEVEL JET THURSDAY
AFTERNOON...WHICH WITH 35-40KTS OF DEEP-LAYER SHEAR WILL ONLY
INCREASE PROBABILITIES FOR PRECIPITATION THURSDAY AFTERNOON. THIS
EASTERN NORTH AMERICA TROUGH AXIS EXTENDING FROM JAMES BAY SWD
THRU THE GRT LKS/MID- SOUTH TO THE CENTRAL GULF COAST WILL PUSH
SLOWLY EWD AND SHOULD REACH THE EAST COAST BY 00Z SAT. THIS WILL
ALLOW FOR PERSISTENT INSTABILITY OVER THE AREA THROUGH THE END OF
THE WEEK...WITH COLD NORTHWESTERLY FLOW BEHIND THE FRONT. THE
GUIDANCE IS SHOWING SOME NOTABLE DIFFS WITH THE H5 SYSTEM. THE
NAM/GFS/GEFS ARE SLOWER AND SHARPER WITH TROUGH AS IT CROSSES THE
OH VLY INTO THE MID- ATLC. THE 00Z GFS EVEN CLOSES OFF THE H5 LOW
OVER NRN VA FRI EVE. THE LAST TWO RUNS OF THE CMC HAVE BEEN TRYING
TO GENERATE A TROPICAL CYCLONE- LIKE SYSTEM NEAR THE OUTER BANKS.
THE KNOWN SLOW/TROPICAL BIASES OF THE NAM/CMC AND STRONG/CLOSED
SOLN OF THE GFS LEADS TO A UKMET/ECMWF PREFERRED SOLN WHICH FAVORS
MORE EWD PROGRESSION WITH THE TROUGH AND ITS ASSOCD COLD FRONT.

BEHIND THE DEPARTING COLD FRONT...A STG AND LARGE ANTICYCLONE
SHOULD DOMINATE PATTERN IN THE FRI-MON TIMEFRAME...BUILDING SEWD
FROM NUNAVUT CANADA ACROSS THE GRT LKS INTO THE NORTHEAST. AN
UNSEASONABLY COLD/DRY AIRMASS WILL ACCOMPANY THE HIGH RESULTING IN
BELOW NORMAL TEMPS FOR MEMORIAL DAY WEEKEND. ECENS MOS DATA SHOWS
TEMPS ON FRI/SAT STRUGGLING TO CRACK THE 60F MARK LOCALLY...WITH
SEVERAL OPPORTUNITIES FOR A LATE-SEASON FROST OVER THE NRN MTNS
SAT/SUN/MON MORNINGS. HOWEVER CURRENT LOW TEMPS REMAIN ABOVE 40
FOR MOST OF THE REGION WITH THE EXCEPTION BEING ALONG THE NEW YORK
BORDER. WINDS SHOULD REMAIN GUSTY SATURDAY MORNING. THE BETTER
CHANCE FOR FROST WILL BE SUNDAY MORNING...TEMPERATURES WILL BE SLIGHTLY
WARMER BUT THE WINDS SHOULD BE LIGHT TO CALM. THERE SHOULD BE A
MODERATION INTO THE MIDDLE OF NEXT WEEK WITH TEMPS GETTING BACK TO
NEAR NORMAL AROUND 5/28.

&&

.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
ALL CENTRAL PA TAF SITES WILL STAY PRIMARILY VFR THROUGH AT LEAST
EARLY THIS EVENING.

HOWEVER...SCT LATE PM TSRA WILL BE AN AVIATION CONCERN. THE BEST CHC
OF TSRA AND ACCOMPANYING BRIEF VSBY REDUCTION/GUSTY WINDS WILL BE
ACROSS THE CENTRAL RIDGE AND VALLEY REGION AND POINTS NORTH TWD THE
NEW YORK BORDER. LATEST MDL DATA CONTINUES TO INDICATE SOME
POSSIBILITY OF A BKN LINE OF TSRA DEVELOPING SOMEWHERE NEAR THE
I-99/RT 220 CORRIDOR FROM KJST/KAOO...NE TO KIPT...THEN SWEEPING SE
ACROSS CENTRAL PENN AND TWD THE SUSQ VALLEY THIS EVENING.

CONVECTIVE SHOWERS AND ISOLATED-SCT TSRA WILL DIMINISH AFTER 06Z
WITH MVFR HAZE LOWERING TO AREAS OF IFR STRATUS AND FOG THROUGH 12
OR 13Z WED. MAINLY VFR TO HIGH END MVFR LATER WEDNESDAY MORNING INTO
THE EARLY AFTERNOON BEFORE MORE SHOWERS AND TSRA DEVELOP ACROSS
CENTRAL PENN IN THE 18Z-23Z WINDOW.

.OUTLOOK...
THU...SCT THUNDERSTORM IMPACTS POSSIBLE...MAINLY IN THE PM.
FRI-MON...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...LAMBERT/STEINBUGL
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT/STEINBUGL
LONG TERM...CERU/STEINBUGL
AVIATION...LAMBERT

000
FXUS61 KCTP 211900
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
255 PM EDT TUE MAY 21 2013

.SYNOPSIS...
A WARM AND HUMID...SUMMERTIME AIRMASS WILL CONTINUE TO BRING WELL
ABOVE NORMAL TEMPERATURES TO CENTRAL PENNSYLVANIA LATE TODAY THROUGH
WEDNESDAY. A COLD FRONT WILL CROSS THE REGION ON THURSDAY. A LARGE
AREA OF HIGH PRESSURE WILL BUILD SOUTHEAST FROM CENTRAL CANADA INTO
THE NORTHEAST AND MID-ATLANTIC STATES. THIS HIGH WILL BRING COOLER
AND DRIER AIR TO THE AREA FOR MEMORIAL DAY WEEKEND...THAT COULD
LAST RIGHT THROUGH MONDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
EARLY AFTERNOON VISIBLE SATELLITE LOOP SHOWS CU FIELD GRADUALLY
EXPANDING EAST FROM THE ALLEGHENY PLATEAU OF NORTHERN AND WRN PENN
AND BEGINNING TO GROW A BIT VERTICALLY.

THE LIMITING FACTORS TO EXPLOSIVE TSRA DEVELOPMENT SO FAR IN THE
HIGHLY UNSTABLE AIRMASS AT LLVLS HAS BEEN THE WSWRLY AND BROADLY
DIFFLUENT FLOW WITHIN THE 925-850 MB LAYER...BENEATH A LARGE POOL OF
QUITE WARM AIR /+7-8C AT 700 MB/...AND WEAK RIDGING ALOFT. THIS WILL
SERVE TO LIMIT CONVECTION ACROSS THE CWA THROUGH 20-21Z.

HIGH RESOLUTION 12-17Z MODEL GUIDANCE CONTINUES TO DEVELOP VERY
ROBUST...LATE DAY ML CAPE OF OVER 2000 J/KG WITHIN THE AREA OF MOST
ABUNDANT SUNSHINE SO FAR THIS AFTERNOON. AS THE RATHER FLAT RIDGING
SLIDES JUST EAST OF THE AREA LATER TODAY...A FAIRLY WELL-DEFINED LEE
TROUGH SHOULD FORM EAST OF THE ALLEGHENY FRONT AND PROVIDE ENOUGH
LLVL CONVERGENCE /IN CONCERT WITH SLIGHT COOLING ALOFT ARRIVING FROM
THE WEST/ TO SPARK ISOLATED TO SCATTERED STRONG TO POTENTIALLY
TSRA. SINCE THE LAST AFD...SPC HAS GREATLY EXPANDED THEIR DY1 SLIGHT
RISK AREA TO ENCOMPASS ABOUT THE NWRN TWO-THIRDS OF PENN...WITH SVR
TSRA WATCH 203 RECENTLY POSTED ISSUED FOR MUCH OF NEW YORK...RIGHT
AGAINST THE ENTIRE PA/NY BORDER.

SREF PROP OF CAPE EXCEEDING 1200 J/KG IS PEGGED BETWEEN AT 100
PERCENT FOR ALL BUT THE EXTREME SERN ZONES BETWEEN 20-23Z TODAY.

NAM HAS BEEN WOBBLING EAST AND WEST A BIT WITH IT/S DEPICTION OF THE
AXIS OF RELATIVELY HIGH EHI. 00-06Z RUNS WERE A BIT FURTHER EAST
ACROSS THE SUSQ VALLEY WITH VALUES AROUND 1.5 M2/S2...WHILE THE
FRESH 12Z RUN IS PAINTING A WIDE STRIPE OF MORE OMINOUS 2-2.5 MS/S2
EHI CENTERED ON A LINE FROM NEAR KELM...TO KUNV AND KAOO BY 00Z WED.

THIS TYPE OF EHI...WITH PRECEDING ABUNDANT INSOLATION IS QUITE
INFREQUENT IN THIS NECK OF THE WOODS. TYPICALLY...MORE PRONOUNCED
SHEAR AND FORCING HERE IN CENTRAL PENN USUALLY RESULTS IN MORE EARLY
DAY CONVECTION /OR STRATIFORM PRECIP/ WHICH LATER LIMITS THE DEGREE
OF LLVL-BASED INSTABILITY.

THE STRENGTHENING SWRLY FLOW AT 850 MB /TO AROUND 30 KTS LATE TODAY/
IS THE MOST CONCERNING FOR THE SEVERE THREAT ACROSS THE CENTRAL
RIDGE AND VALLEY REGION. IF WE CAN GET CONVECTION TO INITIATE WITHIN
THIS HIGHLY PRIMED/UNSTABLE ATMOS...STORMS COULD EASILY BECOME VERY
TALL AND LOCALLY SEVERE.

WEAK HT FALLS WILL DEVELOP IN ASSOCIATION WITH A S/W CRESTING THE
UPPER RIDGE OVER THE UPPER GRT LKS...AND NOSE OF STG LLJ WILL MOVE
NE INTO THE THE UPPER OH VLY/NW PA BY 00Z WED. THE MODELS SHOW A
MCS WITH THIS FEATURE MOVG EWD ACRS THE ERN GRT LKS/ST. LAWRENCE VLY
INTO NRN NEW ENGLAND. HIGHEST POPS OVERNIGHT ARE ACRS THE NRN
TIER...WITH NWD DISPLACEMENT MDL BIAS ARGUING FOR A MORE SRN MCS
TRACK. IN ADDITION...A LINGERING...NEARLY NORTH/SOUTH RIBBON OF HIGH
ML CAPE ACROSS THE SUSQ VALLEY COULD SUPPORT CONTINUED SCATTERED
SHRA/TSRA THERE THROUGH ABOUT 06Z WED.

THE SOUTHWEST LLVL FLOW WILL CONTINUE TO ADVECT VERY WARM AND MOIST
AIR INTO THE REGION WITH MID TO LATE AFTERNOON TEMPS TOPPING OUT
WELL INTO THE 80S ACROSS THE VALLEYS OF CENTRAL AND SRN PENN...AND
SFC DEWPOINTS IN THE LOWER TO MID 60S. MAX TEMPS ACROSS THE MTNS
WILL BE 80-84F.

CONVECTION WILL GRADUALLY DIMINISH LATE TONIGHT WITH WIND BECOMING
LIGHT IN THE MUGGY AIRMASS. PATCHY 1-2SM FOG WILL FORM AFTER
07Z...AND COULD BE LOCALLY DENSE IN THE VALLEYS WHERE RAINFALL
OCCURS.

&&

.SHORT TERM /WEDNESDAY/...
A S/W MOVG EWD ACRS THE UPPER MS VLY INVOF IA WILL PHASE WITH A
CANADIAN UPPER LOW/TROUGH DROPPING SWD ACRS HUDSON/JAMES BAY DURING
THE DAY WEDNESDAY...REACHING THE MIDWEST BY F48. AT THE SFC...A
COLD FRONT PUSHING EWD THRU THE OH VLY WILL BE THE MAIN FOCUS FOR
TSTM DEVELOPMENT/SVR POTENTIAL THIS PERIOD.

AM CLOUDS WITH SOME SPOTTY SHOWERS AND AREAS OF 1-2SM FIG WILL
COMBINE WITH WEAK RIDGING WITHIN THE PREDOMINANT SWRLY FLOW
ALOFT...TO LIMIT DIURNAL HEATING TO SOME EXTENT ACRS THE DAY 2 SPC
SLGT RISK AREA - WHICH COVERS NEARLY ALL OF THE CWA WITH THE
EXCEPTION OF THE FAR SERN ZONES. ALTHOUGH LOW TO MID LEVEL WINDS
WILL BE STRONGEST ACROSS THE NW HALF OF PENN...LATEST SREF AND SHORT
RANGE MODEL GUIDANCE PAINTS THE GREATEST PROBABILITY FOR CAPE
GREATER THAN 1200 J/KG ACROSS THE LOWER SUSQ VALLEY LATE WEDNESDAY
AFTERNOON.

DESPITE THE TEMPERED DESTABILIZATION...EXPECT AN AFTN INCREASE IN
TSTM COVERAGE /WITH LOWER CLOUD BASES COMPARED TO TUESDAY`S/ ALONG
WITH SOME PICK-UP IN INTENSITY AS BELT OF STRONGER FLOW ALOFT SHIFTS
EWD AHEAD OF THE MID-UPPER TROUGH. BANDS OF TSTMS CAPABLE OF
PRODUCING DMGG WNDS/MARGINAL HAIL WILL BE POSSIBLE AND THUS WILL
CONTINUE TO HIGHLIGHT AN ELEVATED SVR WX THREAT IN THE HWO FOR
WEDNESDAY. BETTER FORCING PORTENDS HIGHER POPS RANGING FROM THE
MED-HIGH CHC RANGE IN THE SE TO LOW LKLYS IN THE NW. SHOWERS/TSTMS
MAY PERSIST AFTER DARK INTO WED NGT.

MAX TEMPS WILL LIKELY BE 3-5F LOWER THAN TUESDAY...BUT STILL AROUND
12F ABOVE NORMAL.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
ERN NOAM TROUGH AXIS EXTENDING FROM JAMES BAY SWD THRU THE GRT
LKS/MID-SOUTH TO THE CENTRAL GULF COAST AT THE START OF THE PERIOD
WILL PUSH SLOWLY EWD AND SHOULD REACH THE EAST COAST BY 00Z SAT.
THE GUIDANCE IS SHOWING SOME NOTABLE DIFFS WITH THE H5 SYSTEM. THE
NAM/GFS/GEFS ARE SLOWER AND SHARPER WITH TROUGH AS IT CROSSES THE
OH VLY INTO THE MID-ATLC. THE 00Z GFS EVEN CLOSES OFF THE H5 LOW
OVER NRN VA FRI EVE. THE LAST TWO RUNS OF THE CMC HAVE BEEN TRYING
TO GENERATE A TROPICAL CYCLONE-LIKE SYSTEM NEAR THE OUTER BANKS.
THE KNOWN SLOW/TROPICAL BIASES OF THE NAM/CMC AND STRONG/CLOSED
SOLN OF THE GFS LEADS TO A UKMET/ECMWF PREFERRED SOLN WHICH FAVORS
MORE EWD PROGRESSION WITH THE TROUGH AND ITS ASSOCD COLD FRONT.

THE COLD FRONT WILL CROSS THE CWA ON THURS ACCOMPANIED BY SCT TO
NMRS SHOWERS AND TSTMS. MUCH LIKE ON DAY 2...THE PRE-FRONTAL WARM
SECTOR /LOCATED OVER THE ERN 1/2 OF PA/ WILL BE CHARACTERIZED BY
35-40KTS OF DEEP-LAYER SHEAR WITH WEAK INSTABILITY. THEREFORE THE
OVERALL SVR POTENTIAL APPEARS RELATIVELY LOW ATTM. THE SPC DAY 3
OUTLOOK DOES INCLUDE ERN PA IN THE SEE TEXT/5% SVR FOR ISOLATED
HAIL AND WIND THREAT.

BEHIND THE DEPARTING COLD FRONT...A STG AND LARGE ANTICYCLONE
SHOULD DOMINATE PATTERN IN THE FRI-MON TIMEFRAME...BUILDING SEWD
FROM NUNAVUT ACRS THE GRT LKS INTO THE NORTHEAST. AN UNSEASONABLY
COLD/DRY AIRMASS WILL ACCOMPANY THE HIGH RESULTING IN BLW NORMAL
TEMPS FOR MEMORIAL DAY WEEKEND. ECENS MOS DATA SHOWS TEMPS ON
FRI/SAT STRUGGLING TO CRACK THE 60F MARK LOCALLY...WITH SEVERAL
OPPORTUNITIES FOR A LATE-SEASON FROST OVER THE NRN MTNS SAT/SUN/MON
MORNINGS. THERE SHOULD BE A MODERATION INTO THE MIDDLE OF NEXT
WEEK WITH TEMPS GETTING BACK TO NEAR NORMAL AROUND 5/28.

&&

.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
ALL CENTRAL PA TAF SITES WILL STAY PRIMARILY VFR THROUGH AT LEAST
EARLY THIS EVENING.

HOWEVER...SCT LATE PM TSRA WILL BE AN AVIATION CONCERN. THE BEST CHC
OF TSRA AND ACCOMPANYING BRIEF VSBY REDUCTION/GUSTY WINDS WILL BE
ACROSS THE CENTRAL RIDGE AND VALLEY REGION AND POINTS NORTH TWD THE
NEW YORK BORDER. LATEST MDL DATA CONTINUES TO INDICATE SOME
POSSIBILITY OF A BKN LINE OF TSRA DEVELOPING SOMEWHERE NEAR THE
I-99/RT 220 CORRIDOR FROM KJST/KAOO...NE TO KIPT...THEN SWEEPING SE
ACROSS CENTRAL PENN AND TWD THE SUSQ VALLEY THIS EVENING.

CONVECTIVE SHOWERS AND ISOLATED-SCT TSRA WILL DIMINISH AFTER 06Z
WITH MVFR HAZE LOWERING TO AREAS OF IFR STRATUS AND FOG THROUGH 12
OR 13Z WED. MAINLY VFR TO HIGH END MVFR LATER WEDNESDAY MORNING INTO
THE EARLY AFTERNOON BEFORE MORE SHOWERS AND TSRA DEVELOP ACROSS
CENTRAL PENN IN THE 18Z-23Z WINDOW.

.OUTLOOK...
THU...SCT THUNDERSTORM IMPACTS POSSIBLE...MAINLY IN THE PM.
FRI-MON...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...LAMBERT/STEINBUGL
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT/STEINBUGL
LONG TERM...STEINBUGL
AVIATION...LAMBERT

000
FXUS61 KCTP 211518
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1000 AM EDT TUE MAY 21 2013

.SYNOPSIS...
A WARM AND HUMID...SUMMERTIME AIRMASS WILL CONTINUE TO BRING ABOVE
NORMAL TEMPERATURES TO CENTRAL PENNSYLVANIA THROUGH WEDNESDAY. A
COLD FRONT WILL CROSS THE REGION ON THURSDAY. A LARGE AREA OF HIGH
PRESSURE WILL BUILD SOUTH AND EAST FROM CENTRAL CANADA INTO THE
NORTHEAST AND MID-ATLANTIC STATES...BRINGING COOLER AND DRIER AIR
TO THE AREA FOR MEMORIAL DAY WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
LATE MORNING VISIBLE SATELLITE LOOP SHOWS QUICKLY ERODING FOG/LOW
STRATUS ACROSS THE LOWER SUSQ VALLEY...AND SLOW EASTWARD MIGRATION
OF A BKN...AND GENERALLY SHALLOW STRATOCU FIELD ACROSS THE ALLEGHENY
PLATEAU.

BROAD...WESTERLY DIFFLUENT FLOW WITHIN THE 925-850 MB LAYER...
BENEATH AN AREA OF QUITE WARM AIR /+7C AT 700 MB/...AND WEAK RIDGING
ALOFT WILL SERVE TO LIMIT CONVECTION THROUGH THE EARLY-MID AFTERNOON
HOURS.

HIGH RESOLUTION MODEL GUIDANCE DOES DEVELOP VERY ROBUST ML CAPE OF
OVER 2000 J/KG WITHIN THE AREA OF ABUNDANT SUNSHINE THIS AFTERNOON.
AS THE RATHER FLAT RIDGING SLIDES JUST EAST OF THE AREA LATER
TODAY...A FAIRLY WELL-DEFINED LEAD TROUGH SHOULD FORM EAST OF THE
ALLEGHENY FRONT AND SHOULD PROVIDE ENOUGH LLVL CONVERGENCE /IN
CONCERT WITH SLIGHT COOLING ALOFT/ TO SPARK ISOLATED TO SCATTERED
TSRA.

NAM HAS BEEN WOBBLING EAST AND WEST A BIT WITH IT/S DEPICTION OF THE
AXIS OF RELATIVELY HIGH EHI. 00-06Z RUNS WERE A BIT FURTHER EAST
ACROSS THE SUSQ VALLEY WITH VALUES AROUND 1.5 M2/S2...WHILE THE
FRESH 12Z RUN IS PAINTING A WIDE STRIPE OF MORE OMINOUS 2-2.5 MS/S2
EHI CENTERED ON A LINE FROM NEAR KELM...TO KUNV AND KAOO BY 00Z WED.

THIS TYPE OF EHI...WITH PRECEDING ABUNDANT INSOLATION IS QUITE
INFREQUENT IN THIS NECK OF THE WOODS. TYPICALLY...MORE PRONOUNCED
SHEAR AND FORCING HERE IN CENTRAL PENN USUALLY RESULTS IN MORE EARLY
DAY CONVECTION /OR STRATIFORM PRECIP/ WHICH LATER LIMITS THE DEGREE
OF LLVL-BASED INSTABILITY.

THE STRENGTHENING SWRLY FLOW AT 850 MB /TO AROUND 30 KTS LATE TODAY/
IS THE MOST CONCERNING FOR THE SEVERE THREAT ACROSS THE CENTRAL
RIDGE AND VALLEY REGION. IF WE CAN GET CONVECTION TO INITIATE WITHIN
THIS HIGHLY PRIMED/UNSTABLE ATMOS...STORMS COULD EASILY BECOME VERY
TALL AND LOCALLY SEVERE.

AS NOTED BY THE PREVIOUS SHIFT`S DISCUSSION...THE SPC CATG OUTLOOK
HIGHLIGHTS NRN PA IN THE SEE TEXT WITH 5% PROB OF DMGG WINDS. THIS
AREA MAY BE INFLUENCED BY WEAK HT FALLS ASSOCD WITH S/W CRESTING THE
UPPER RIDGE OVER THE UPPER GRT LKS...AND NOSE OF STG LLJ IN THE
UPPER OH VLY/NW PA BY 00Z. THE MODELS SHOW A MCS WITH THIS FEATURE
MOVG EWD ACRS THE ERN GRT LKS/ST. LAWRENCE VLY INTO NRN NEW ENGLAND.
HIGHEST POPS OVERNIGHT ARE ACRS THE NRN TIER...WITH NWD DISPLACEMENT
MDL BIAS ARGUING FOR A MORE SRN MCS TRACK.

THE SOUTHWEST LLVL FLOW WILL CONTINUE TO ADVECT VERY WARM AND MOIST
AIR INTO THE REGION WITH AFTERNOON TEMPS IN THE 80S AND SFC
DEWPOINTS IN THE LOWER TO MID 60S.
&&

.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
A S/W MOVG EWD ACRS THE UPPER MS VLY INVOF IA WILL PHASE WITH A
CANADIAN UPPER LOW/TROUGH DROPPING SWD ACRS HUDSON/JAMES BAY DURING
THE DAY WEDNESDAY...REACHING THE MIDWEST BY F72. AT THE SFC...A
COLD FRONT PUSHING EWD THRU THE OH VLY WILL BE THE MAIN FOCUS FOR
TSTM DEVELOPMENT/SVR POTENTIAL THIS PERIOD.

AM CLOUDS WITH SOME PCPN IS EXPECTED TO LIMIT DIURNAL HEATING
TO SOME EXTENT ACRS THE DAY 2 SPC SLGT RISK AREA - WHICH COVERS
NEARLY ALL OF THE CWA WITH THE EXCEPTION OF THE FAR SERN ZONES.
DESPITE THE TEMPERED DESTABILIZATION...EXPECT AN AFTN INCREASE IN
TSTM COVERAGE ALONG WITH SOME PICK-UP IN INTENSITY AS BELT OF
STRONGER FLOW ALOFT SHIFTS EWD AHEAD OF THE MID-UPPER TROUGH.
BANDS OF TSTMS CAPABLE OF PRODUCING DMGG WNDS/MARGINAL HAIL WILL
BE POSSIBLE AND THUS WILL CONTINUE TO HIGHLIGHT AN ELEVATED SVR WX
THREAT IN THE HWO FOR WEDNESDAY. BETTER FORCING PORTENDS HIGHER
POPS RANGING FROM THE MED-HIGH CHC RANGE IN THE SE TO LOW LKLYS IN
THE NW. SHOWERS/TSTMS MAY PERSIST AFTER DARK INTO WED NGT.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
ERN NOAM TROUGH AXIS EXTENDING FROM JAMES BAY SWD THRU THE GRT
LKS/MID-SOUTH TO THE CENTRAL GULF COAST AT THE START OF THE PERIOD
WILL PUSH SLOWLY EWD AND SHOULD REACH THE EAST COAST BY 00Z SAT.
THE GUIDANCE IS SHOWING SOME NOTABLE DIFFS WITH THE H5 SYSTEM. THE
NAM/GFS/GEFS ARE SLOWER AND SHARPER WITH TROUGH AS IT CROSSES THE
OH VLY INTO THE MID-ATLC. THE 00Z GFS EVEN CLOSES OFF THE H5 LOW
OVER NRN VA FRI EVE. THE LAST TWO RUNS OF THE CMC HAVE BEEN TRYING
TO GENERATE A TROPICAL CYCLONE-LIKE SYSTEM NEAR THE OUTER BANKS.
THE KNOWN SLOW/TROPICAL BIASES OF THE NAM/CMC AND STRONG/CLOSED
SOLN OF THE GFS LEADS TO A UKMET/ECMWF PREFERRED SOLN WHICH FAVORS
MORE EWD PROGRESSION WITH THE TROUGH AND ITS ASSOCD COLD FRONT.

THE COLD FRONT WILL CROSS THE CWA ON THURS ACCOMPANIED BY SCT TO
NMRS SHOWERS AND TSTMS. MUCH LIKE ON DAY 2...THE PRE-FRONTAL WARM
SECTOR /LOCATED OVER THE ERN 1/2 OF PA/ WILL BE CHARACTERIZED BY
35-40KTS OF DEEP-LAYER SHEAR WITH WEAK INSTABILITY. THEREFORE THE
OVERALL SVR POTENTIAL APPEARS RELATIVELY LOW ATTM. THE SPC DAY 3
OUTLOOK DOES INCLUDE ERN PA IN THE SEE TEXT/5% SVR FOR ISOLATED
HAIL AND WIND THREAT.

BEHIND THE DEPARTING COLD FRONT...A STG AND LARGE ANTICYCLONE
SHOULD DOMINATE PATTERN IN THE FRI-MON TIMEFRAME...BUILDING SEWD
FROM NUNAVUT ACRS THE GRT LKS INTO THE NORTHEAST. AN UNSEASONABLY
COLD/DRY AIRMASS WILL ACCOMPANY THE HIGH RESULTING IN BLW NORMAL
TEMPS FOR MEMORIAL DAY WEEKEND. ECENS MOS DATA SHOWS TEMPS ON
FRI/SAT STRUGGLING TO CRACK THE 60F MARK LOCALLY...WITH SEVERAL
OPPORTUNITIES FOR A LATE-SEASON FROST OVER THE NRN MTNS SAT/SUN/MON
MORNINGS. THERE SHOULD BE A MODERATION INTO THE MIDDLE OF NEXT
WEEK WITH TEMPS GETTING BACK TO NEAR NORMAL AROUND 5/28.

&&

.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
MID MORNING FOG HAS BURNED OFF...WITH ALL CENTRAL PA TAF SITES NOW
VFR.

HOWEVER...SCT PM TSRA WILL AGAIN BE AN AVIATION CONCERN. THE BEST
CHC OF AN AFTN TSRA AND ACCOMPANYING BRIEF VSBY REDUCTION WILL BE
ACROSS THE CENTRAL RIDGE AND VALLEY REGION AND POINTS WEST OVER THE
ALLEGHENY PLATEAU. HOWEVER...LATEST MDL DATA INDICATES SOME
POSSIBILITY OF A LINE OF TSRA DEVELOPING SOMEWHERE NEAR THE I-99/RT
220 CORRIDOR FROM KJST/KAOO...NE TO KIPT...THEN SWEEPING SE ACROSS
CENTRAL PENN AND TWD THE SUSQ VALLEY.

.OUTLOOK...
WED-THU...SCT THUNDERSTORM IMPACTS POSSIBLE...MAINLY IN THE PM.
FRI-SAT...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...LAMBERT/STEINBUGL
NEAR TERM...LAMBERT
SHORT TERM...STEINBUGL
LONG TERM...STEINBUGL
AVIATION...LAMBERT

000
FXUS61 KCTP 211113
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
713 AM EDT TUE MAY 21 2013

.SYNOPSIS...
A WARM AND HUMID...SUMMERTIME AIRMASS WILL CONTINUE TO BRING ABOVE
NORMAL TEMPERATURES TO CENTRAL PENNSYLVANIA THROUGH WEDNESDAY. A
COLD FRONT WILL CROSS THE REGION ON THURSDAY. A LARGE AREA OF HIGH
PRESSURE WILL BUILD SOUTH AND EAST FROM CENTRAL CANADA INTO THE
NORTHEAST AND MID-ATLANTIC STATES...BRINGING COOLER AND DRIER AIR
TO THE AREA FOR MEMORIAL DAY WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
IR SATL/SFC OBS INDICATE FOG IS QUICKLY DEVELOPING ESP ACRS
S-CNTRL AND SERN PA. SOME OF THE FOG WILL BE LCLY DENSE EARLY THIS
MORNING WITH VIS AOB 1/2-1/4SM. FOG AND LOW ST WILL GIVE WAY TO
M/SUNNY SKIES BY MID-LATE MORNING WITH TEMPS 75-80F BY NOON.

AN UPPER-LEVEL RIDGE WILL BE IN PLACE OVER CNTRL PA DURING THE
DAY 1 PERIOD...GRADUALLY WEAKENING AND SLIDING EWD THROUGH
TONIGHT. SOUTHWEST LLVL FLOW WILL CONTINUE TO ADVECT VERY WARM AND
MOIST AIR INTO THE REGION WITH AFTERNOON TEMPS IN THE 80S AND SFC
DEWPOINTS IN THE LOWER TO MID 60S. DESPITE WEAK LG SCALE FORCING
FOR ASCENT...MODERATE INSTABILITY /MEAN ML CAPE VALUES BETWEEN
1000-2000 J/KG/ SHOULD SUPPORT ISOLD-SCT CONVECTION DURING THE
AFTN-EVE. THE OVERALL SVR THREAT LOOKS MARGINAL GIVEN THE ABSENCE
OF A SIGNIFICANT TRIGGER...HOWEVER THE SPC CATG OUTLOOK HIGHLIGHTS
NRN PA IN THE SEE TEXT WITH 5% PROB OF DMGG WINDS. THIS AREA
MAY BE INFLUENCED BY WEAK HT FALLS ASSOCD WITH S/W CRESTING THE
UPPER RIDGE OVER THE UPPER GRT LKS...AND NOSE OF STG LLJ IN THE
UPPER OH VLY/NW PA BY 00Z. THE MODELS SHOW A MCS WITH THIS FEATURE
MOVG EWD ACRS THE ERN GRT LKS/ST. LAWRENCE VLY INTO NRN NEW
ENGLAND. HIGHEST POPS OVERNIGHT ARE ACRS THE NRN TIER...WITH NWD
DISPLACEMENT MDL BIAS ARGUING FOR A MORE SRN MCS TRACK.

&&

.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
A S/W MOVG EWD ACRS THE UPPER MS VLY INVOF IA WILL PHASE WITH A
CANADIAN UPPER LOW/TROUGH DROPPING SWD ACRS HUDSON/JAMES BAY DURING
THE DAY WEDNESDAY...REACHING THE MIDWEST BY F72. AT THE SFC...A
COLD FRONT PUSHING EWD THRU THE OH VLY WILL BE THE MAIN FOCUS FOR
TSTM DEVELOPMENT/SVR POTENTIAL THIS PERIOD.

AM CLOUDS WITH SOME PCPN IS EXPECTED TO LIMIT DIURNAL HEATING
TO SOME EXTENT ACRS THE DAY 2 SPC SLGT RISK AREA - WHICH COVERS
NEARLY ALL OF THE CWA WITH THE EXCEPTION OF THE FAR SERN ZONES.
DESPITE THE TEMPERED DESTABILIZATION...EXPECT AN AFTN INCREASE IN
TSTM COVERAGE ALONG WITH SOME PICK-UP IN INTENSITY AS BELT OF
STRONGER FLOW ALOFT SHIFTS EWD AHEAD OF THE MID-UPPER TROUGH.
BANDS OF TSTMS CAPABLE OF PRODUCING DMGG WNDS/MARGINAL HAIL WILL
BE POSSIBLE AND THUS WILL CONTINUE TO HIGHLIGHT AN ELEVATED SVR WX
THREAT IN THE HWO FOR WEDNESDAY. BETTER FORCING PORTENDS HIGHER
POPS RANGING FROM THE MED-HIGH CHC RANGE IN THE SE TO LOW LKLYS IN
THE NW. SHOWERS/TSTMS MAY PERSIST AFTER DARK INTO WED NGT.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
ERN NOAM TROUGH AXIS EXTENDING FROM JAMES BAY SWD THRU THE GRT
LKS/MID-SOUTH TO THE CENTRAL GULF COAST AT THE START OF THE PERIOD
WILL PUSH SLOWLY EWD AND SHOULD REACH THE EAST COAST BY 00Z SAT.
THE GUIDANCE IS SHOWING SOME NOTABLE DIFFS WITH THE H5 SYSTEM. THE
NAM/GFS/GEFS ARE SLOWER AND SHARPER WITH TROUGH AS IT CROSSES THE
OH VLY INTO THE MID-ATLC. THE 00Z GFS EVEN CLOSES OFF THE H5 LOW
OVER NRN VA FRI EVE. THE LAST TWO RUNS OF THE CMC HAVE BEEN TRYING
TO GENERATE A TROPICAL CYCLONE-LIKE SYSTEM NEAR THE OUTER BANKS.
THE KNOWN SLOW/TROPICAL BIASES OF THE NAM/CMC AND STRONG/CLOSED
SOLN OF THE GFS LEADS TO A UKMET/ECMWF PREFERRED SOLN WHICH FAVORS
MORE EWD PROGRESSION WITH THE TROUGH AND ITS ASSOCD COLD FRONT.

THE COLD FRONT WILL CROSS THE CWA ON THURS ACCOMPANIED BY SCT TO
NMRS SHOWERS AND TSTMS. MUCH LIKE ON DAY 2...THE PRE-FRONTAL WARM
SECTOR /LOCATED OVER THE ERN 1/2 OF PA/ WILL BE CHARACTERIZED BY
35-40KTS OF DEEP-LAYER SHEAR WITH WEAK INSTABILITY. THEREFORE THE
OVERALL SVR POTENTIAL APPEARS RELATIVELY LOW ATTM. THE SPC DAY 3
OUTLOOK DOES INCLUDE ERN PA IN THE SEE TEXT/5% SVR FOR ISOLATED
HAIL AND WIND THREAT.

BEHIND THE DEPARTING COLD FRONT...A STG AND LARGE ANTICYCLONE
SHOULD DOMINATE PATTERN IN THE FRI-MON TIMEFRAME...BUILDING SEWD
FROM NUNAVUT ACRS THE GRT LKS INTO THE NORTHEAST. AN UNSEASONABLY
COLD/DRY AIRMASS WILL ACCOMPANY THE HIGH RESULTING IN BLW NORMAL
TEMPS FOR MEMORIAL DAY WEEKEND. ECENS MOS DATA SHOWS TEMPS ON
FRI/SAT STRUGGLING TO CRACK THE 60F MARK LOCALLY...WITH SEVERAL
OPPORTUNITIES FOR A LATE-SEASON FROST OVER THE NRN MTNS SAT/SUN/MON
MORNINGS. THERE SHOULD BE A MODERATION INTO THE MIDDLE OF NEXT
WEEK WITH TEMPS GETTING BACK TO NEAR NORMAL AROUND 5/28.

&&

.AVIATION /11Z TUESDAY THROUGH SATURDAY/...
AM FOG IS IN THE PROCESS OF BURNING OFF AND SHOULD DO SO
COMPLETELY BY 13-14Z. AFTER THAT...THERE IS A HIGH DEGREE OF
CONFIDENCE IN WIDESPREAD VFR CONDS FROM LATE AM THRU THIS EVENING.
HOWEVER...SCT PM TSRA WILL AGAIN BE AN AVIATION CONCERN. THE BEST
CHC OF AN AFTN TSRA AND ACCOMPANYING BRIEF VSBY REDUCTION WILL BE
ACROSS THE N MTNS AND SOUTHWARD ALONG THE LAUREL HIGHLANDS.
HOWEVER...LATEST MDL DATA INDICATES SOME POSSIBILITY OF A LINE OF
TSRA SWEEPING SE ACROSS THE ENTIRE REGION LATE THIS EVENING.

.OUTLOOK...
WED-THU...SCT THUNDERSTORM IMPACTS POSSIBLE...MAINLY IN THE PM.
FRI-SAT...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...STEINBUGL
AVIATION...FITZGERALD/GARTNER

000
FXUS61 KCTP 210945
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
545 AM EDT TUE MAY 21 2013

.SYNOPSIS...
A WARM AND HUMID...SUMMERTIME AIRMASS WILL CONTINUE TO BRING ABOVE
NORMAL TEMPERATURES TO CENTRAL PENNSYLVANIA THROUGH WEDNESDAY. A
COLD FRONT WILL CROSS THE REGION ON THURSDAY. A LARGE AREA OF HIGH
PRESSURE WILL BUILD SOUTH AND EAST FROM CENTRAL CANADA INTO THE
NORTHEAST AND MID-ATLANTIC STATES...BRINGING COOLER AND DRIER AIR
TO THE AREA FOR MEMORIAL DAY WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
IR SATL/SFC OBS INDICATE FOG IS QUICKLY DEVELOPING ESP ACRS
S-CNTRL AND SERN PA. SOME OF THE FOG WILL BE LCLY DENSE EARLY THIS
MORNING WITH VIS AOB 1/2-1/4SM. FOG AND LOW ST WILL GIVE WAY TO
M/SUNNY SKIES BY MID-LATE MORNING WITH TEMPS 75-80F BY NOON.

AN UPPER-LEVEL RIDGE WILL BE IN PLACE OVER CNTRL PA DURING THE
DAY 1 PERIOD...GRADUALLY WEAKENING AND SLIDING EWD THROUGH
TONIGHT. SOUTHWEST LLVL FLOW WILL CONTINUE TO ADVECT VERY WARM AND
MOIST AIR INTO THE REGION WITH AFTERNOON TEMPS IN THE 80S AND SFC
DEWPOINTS IN THE LOWER TO MID 60S. DESPITE WEAK LG SCALE FORCING
FOR ASCENT...MODERATE INSTABILITY /MEAN ML CAPE VALUES BETWEEN
1000-2000 J/KG/ SHOULD SUPPORT ISOLD-SCT CONVECTION DURING THE
AFTN-EVE. THE OVERALL SVR THREAT LOOKS MARGINAL GIVEN THE ABSENCE
OF A SIGNIFICANT TRIGGER...HOWEVER THE SPC CATG OUTLOOK HIGHLIGHTS
NRN PA IN THE SEE TEXT WITH 5% PROB OF DMGG WINDS. THIS AREA
MAY BE INFLUENCED BY WEAK HT FALLS ASSOCD WITH S/W CRESTING THE
UPPER RIDGE OVER THE UPPER GRT LKS...AND NOSE OF STG LLJ IN THE
UPPER OH VLY/NW PA BY 00Z. THE MODELS SHOW A MCS WITH THIS FEATURE
MOVG EWD ACRS THE ERN GRT LKS/ST. LAWRENCE VLY INTO NRN NEW
ENGLAND. HIGHEST POPS OVERNIGHT ARE ACRS THE NRN TIER...WITH NWD
DISPLACEMENT MDL BIAS ARGUING FOR A MORE SRN MCS TRACK.

&&

.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
A S/W MOVG EWD ACRS THE UPPER MS VLY INVOF IA WILL PHASE WITH A
CANADIAN UPPER LOW/TROUGH DROPPING SWD ACRS HUDSON/JAMES BAY DURING
THE DAY WEDNESDAY...REACHING THE MIDWEST BY F72. AT THE SFC...A
COLD FRONT PUSHING EWD THRU THE OH VLY WILL BE THE MAIN FOCUS FOR
TSTM DEVELOPMENT/SVR POTENTIAL THIS PERIOD.

AM CLOUDS WITH SOME PCPN IS EXPECTED TO LIMIT DIURNAL HEATING
TO SOME EXTENT ACRS THE DAY 2 SPC SLGT RISK AREA - WHICH COVERS
NEARLY ALL OF THE CWA WITH THE EXCEPTION OF THE FAR SERN ZONES.
DESPITE THE TEMPERED DESTABILIZATION...EXPECT AN AFTN INCREASE IN
TSTM COVERAGE ALONG WITH SOME PICK-UP IN INTENSITY AS BELT OF
STRONGER FLOW ALOFT SHIFTS EWD AHEAD OF THE MID-UPPER TROUGH.
BANDS OF TSTMS CAPABLE OF PRODUCING DMGG WNDS/MARGINAL HAIL WILL
BE POSSIBLE AND THUS WILL CONTINUE TO HIGHLIGHT AN ELEVATED SVR WX
THREAT IN THE HWO FOR WEDNESDAY. BETTER FORCING PORTENDS HIGHER
POPS RANGING FROM THE MED-HIGH CHC RANGE IN THE SE TO LOW LKLYS IN
THE NW. SHOWERS/TSTMS MAY PERSIST AFTER DARK INTO WED NGT.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
ERN NOAM TROUGH AXIS EXTENDING FROM JAMES BAY SWD THRU THE GRT
LKS/MID-SOUTH TO THE CENTRAL GULF COAST AT THE START OF THE PERIOD
WILL PUSH SLOWLY EWD AND SHOULD REACH THE EAST COAST BY 00Z SAT.
THE GUIDANCE IS SHOWING SOME NOTABLE DIFFS WITH THE H5 SYSTEM. THE
NAM/GFS/GEFS ARE SLOWER AND SHARPER WITH TROUGH AS IT CROSSES THE
OH VLY INTO THE MID-ATLC. THE 00Z GFS EVEN CLOSES OFF THE H5 LOW
OVER NRN VA FRI EVE. THE LAST TWO RUNS OF THE CMC HAVE BEEN TRYING
TO GENERATE A TROPICAL CYCLONE-LIKE SYSTEM NEAR THE OUTER BANKS.
THE KNOWN SLOW/TROPICAL BIASES OF THE NAM/CMC AND STRONG/CLOSED
SOLN OF THE GFS LEADS TO A UKMET/ECMWF PREFERRED SOLN WHICH FAVORS
MORE EWD PROGRESSION WITH THE TROUGH AND ITS ASSOCD COLD FRONT.

THE COLD FRONT WILL CROSS THE CWA ON THURS ACCOMPANIED BY SCT TO
NMRS SHOWERS AND TSTMS. MUCH LIKE ON DAY 2...THE PRE-FRONTAL WARM
SECTOR /LOCATED OVER THE ERN 1/2 OF PA/ WILL BE CHARACTERIZED BY
35-40KTS OF DEEP-LAYER SHEAR WITH WEAK INSTABILITY. THEREFORE THE
OVERALL SVR POTENTIAL APPEARS RELATIVELY LOW ATTM. THE SPC DAY 3
OUTLOOK DOES INCLUDE ERN PA IN THE SEE TEXT/5% SVR FOR ISOLATED
HAIL AND WIND THREAT.

BEHIND THE DEPARTING COLD FRONT...A STG AND LARGE ANTICYCLONE
SHOULD DOMINATE PATTERN IN THE FRI-MON TIMEFRAME...BUILDING SEWD
FROM NUNAVUT ACRS THE GRT LKS INTO THE NORTHEAST. AN UNSEASONABLY
COLD/DRY AIRMASS WILL ACCOMPANY THE HIGH RESULTING IN BLW NORMAL
TEMPS FOR MEMORIAL DAY WEEKEND. ECENS MOS DATA SHOWS TEMPS ON
FRI/SAT STRUGGLING TO CRACK THE 60F MARK LOCALLY...WITH SEVERAL
OPPORTUNITIES FOR A LATE-SEASON FROST OVER THE NRN MTNS SAT/SUN/MON
MORNINGS. THERE SHOULD BE A MODERATION INTO THE MIDDLE OF NEXT
WEEK WITH TEMPS GETTING BACK TO NEAR NORMAL AROUND 5/28.

&&

.AVIATION /09Z TUESDAY THROUGH SATURDAY/...
THE MAIN AVIATION CONCERN OVERNIGHT IS THE POTENTIAL OF FOG. HIGH
DEWPOINTS AND LIGHT WINDS WILL LEAD TO AREAS OF FOG...MAINLY AFTER
06Z. BULK OF MDL GUIDANCE CONTINUES TO TARGET THE EASTERN THIRD OF
THE STATE FOR THE LOWEST VSBYS DUE TO A NEARLY CALM WIND AND LOWER
DWPT DEPRESSIONS IN THIS AREA. THE COMBINATION OF MDL DATA AND 03Z
SFC DWPT DEPRESSIONS SUGGEST KLNS AND KMDT ARE VERY LIKELY TO
EXPERIENCE A PERIOD OF IFR VSBYS LATE TONIGHT. KAOO ALSO APPEARS
LIKELY TO EXPERIENCE A PERIOD OF IFR VSBYS...DUE IN PART TO WET
GROUND FROM A LATE DAY SHRA. ELSEWHERE...THE FOG THREAT NOT QUITE
AS GREAT. HOWEVER...A BRIEF PERIOD OF LOW VSBYS IS POSSIBLE JUST
BEFORE DAWN.

AM FOG SHOULD BURN OFF BY ARND 13Z TUESDAY. AFTER THAT...THERE IS
A HIGH DEGREE OF CONFIDENCE IN WIDESPREAD VFR CONDS FROM LATE AM
THRU TUE EVENING. HOWEVER...SCT PM TSRA WILL AGAIN BE AN AVIATION
CONCERN. THE BEST CHC OF AN AFTN TSRA AND ACCOMPANYING BRIEF VSBY
REDUCTION WILL BE ACROSS THE N MTNS AND SOUTHWARD ALONG THE LAUREL
HIGHLANDS. HOWEVER...LATEST MDL DATA INDICATES SOME POSSIBILITY OF
A LINE OF TSRA SWEEPING SE ACROSS THE ENTIRE REGION TUE EVENING.

.OUTLOOK...
WED-THU...SCT THUNDERSTORM IMPACTS POSSIBLE...MAINLY IN THE PM.
FRI-SAT...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...STEINBUGL
AVIATION...FITZGERALD

000
FXUS61 KCTP 210738
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
338 AM EDT TUE MAY 21 2013

.SYNOPSIS...
A WARM AND HUMID...SUMMERTIME AIRMASS WILL CONTINUE TO BRING ABOVE
NORMAL TEMPERATURES TO CENTRAL PENNSYLVANIA THROUGH WEDNESDAY. A
COLD FRONT WILL CROSS THE REGION ON THURSDAY. A LARGE AREA OF HIGH
PRESSURE WILL BUILD SOUTH AND EAST FROM CENTRAL CANADA INTO THE
NORTHEAST AND MID-ATLANTIC STATES...BRINGING COOLER AND DRIER AIR
TO THE AREA FOR MEMORIAL DAY WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
AN UPPER-LEVEL RIDGE WILL BE IN PLACE OVER CNTRL PA DURING THE
DAY 1 PERIOD...GRADUALLY WEAKENING AND SLIDING EWD THROUGH
TONIGHT. SOUTHWEST LLVL FLOW WILL CONTINUE TO ADVECT VERY WARM AND
MOIST AIR INTO THE REGION WITH AFTERNOON TEMPS IN THE 80S AND SFC
DEWPOINTS IN THE LOWER TO MID 60S. DESPITE WEAK LG SCALE FORCING
FOR ASCENT...MODERATE INSTABILITY /MEAN ML CAPE VALUES BETWEEN
1000-2000 J/KG/ SHOULD SUPPORT ISOLD-SCT CONVECTION DURING THE
AFTN-EVE. THE OVERALL SVR THREAT LOOKS MARGINAL GIVEN THE ABSENCE
OF A SIGNIFICANT TRIGGER...HOWEVER THE SPC CATG OUTLOOK HIGHLIGHTS
NRN PA IN THE SEE TEXT WITH 5% PROB OF DMGG WINDS. THIS AREA
MAY BE INFLUENCED BY WEAK HT FALLS ASSOCD WITH S/W CRESTING THE
UPPER RIDGE OVER THE UPPER GRT LKS...AND NOSE OF STG LLJ IN THE
UPPER OH VLY/NW PA BY 00Z. THE MODELS SHOW A MCS WITH THIS FEATURE
MOVG EWD ACRS THE ERN GRT LKS/ST. LAWRENCE VLY INTO NRN NEW
ENGLAND. HIGHEST POPS OVERNIGHT ARE ACRS THE NRN TIER...WITH NWD
DISPLACEMENT MDL BIAS ARGUING FOR A MORE SRN MCS TRACK.

&&

.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
A S/W MOVG EWD ACRS THE UPPER MS VLY INVOF IA WILL PHASE WITH A
CANADIAN UPPER LOW/TROUGH DROPPING SWD ACRS HUDSON/JAMES BAY DURING
THE DAY WEDNESDAY...REACHING THE MIDWEST BY F72. AT THE SFC...A
COLD FRONT PUSHING EWD THRU THE OH VLY WILL BE THE MAIN FOCUS FOR
TSTM DEVELOPMENT/SVR POTENTIAL THIS PERIOD.

AM CLOUDS WITH SOME PCPN IS EXPECTED TO LIMIT DIURNAL HEATING
TO SOME EXTENT ACRS THE DAY 2 SPC SLGT RISK AREA - WHICH COVERS
NEARLY ALL OF THE CWA WITH THE EXCEPTION OF THE FAR SERN ZONES.
DESPITE THE TEMPERED DESTABILIZATION...EXPECT AN AFTN INCREASE IN
TSTM COVERAGE ALONG WITH SOME PICK-UP IN INTENSITY AS BELT OF
STRONGER FLOW ALOFT SHIFTS EWD AHEAD OF THE MID-UPPER TROUGH.
BANDS OF TSTMS CAPABLE OF PRODUCING DMGG WNDS/MARGINAL HAIL WILL
BE POSSIBLE AND THUS WILL CONTINUE TO HIGHLIGHT AN ELEVATED SVR WX
THREAT IN THE HWO FOR WEDNESDAY. BETTER FORCING PORTENDS HIGHER
POPS RANGING FROM THE MED-HIGH CHC RANGE IN THE SE TO LOW LKLYS IN
THE NW. SHOWERS/TSTMS MAY PERSIST AFTER DARK INTO WED NGT.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
THE LARGE UPPER LEVEL LOW BRINGING SEVERE WEATHER THROUGHOUT THE
MIDWEST WILL SLOWLY MAKE ITS WAY EASTWARD. THIS FLOW SHOULD BRING A
RATHER UNSETTLED PERIOD THROUGH THE WORK WEEK. AS THE UPPER LEVEL
RIDGE CONTINUES TO BREAK DOWN...STORMS WILL SLOWLY APPROACH.  SEVERE
OUTLOOK FOR DAY3/WED HAS THE WESTERN HALF OF THE CWA IN THE SLIGHT
RISK. SOUTHEASTERLY MOISTURE...COUPLED WITH INSTABILITY FROM THE
FRONT AND DAYTIME HIGHS IN THE 80S SHOULD ALLOW FOR A SUFFICIENT
ENVIRONMENT FOR DAYTIME STORMS/SHOWERS. SHEAR SHOULD BE
DECENT...ESPECIALLY AS MID RANGE MODELS ARE HINTING AT A LLJ THROUGH
WEDNESDAY AFTERNOON. THURSDAY WILL AGAIN FEATURE SCT/NMRS TSRA. THE
MED RANGE GUID IS NOW PRETTY SOLID WITH A THURS NIGHT/EARLY FRIDAY
PASSAGE OF THE COLD FRONT ASSOCD WITH THE SYNOPTIC SCALE STORM. MUCH
COOLER AIR AND DRIER CONDITIONS SHOULD FOLLOW FOR THE WEEKEND. ECMWF
HAS BACKED OFF ON THE COLD-NESS OF THE AIR MOVING DOWN WITH THE BIG
1030MB HIGH FOR THE WEEKEND...THOUGH IT LOOKS LIKE THE ZERO C LINE
AT 8H COULD CLIP THE NORTHWESTERN CORNER OF PA. MIN TEMPS FOR
SATURDAY MORNING WILL BE COOL BUT HAVE KEPT THEM IN THE LOW 40S TO
UPPER 30S. DRIER AIR ASSOCIATED WITH THIS FRONT SHOULD KEEP
PRECIPITATION OUT OF THE FORECAST THROUGH THE WEEKEND...WITH WEAK
HIGH PRESSURE BUILDING THROUGH SUNDAY. MEMORIAL DAY MAY SEEM SOME
CLOUDINESS AS THE RIDGE BREAKS DOWN TO DUE NORTHWESTERLY FLOW.
MOISTURE FROM A WEAK SHORTWAVE COULD BRING PRECIPITATION ALONG THE
MASON DIXON MONDAY EVENING...YET DUE TO IT BEING ON THE EDGE OF THE
FORECAST MUCH COULD CHANGE.

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
THE MAIN AVIATION CONCERN OVERNIGHT IS THE POTENTIAL OF FOG. HIGH
DEWPOINTS AND LIGHT WINDS WILL LEAD TO AREAS OF FOG...MAINLY AFTER
06Z. BULK OF MDL GUIDANCE CONTINUES TO TARGET THE EASTERN THIRD OF
THE STATE FOR THE LOWEST VSBYS DUE TO A NEARLY CALM WIND AND LOWER
DWPT DEPRESSIONS IN THIS AREA. THE COMBINATION OF MDL DATA AND 03Z
SFC DWPT DEPRESSIONS SUGGEST KLNS AND KMDT ARE VERY LIKELY TO
EXPERIENCE A PERIOD OF IFR VSBYS LATE TONIGHT. KAOO ALSO APPEARS
LIKELY TO EXPERIENCE A PERIOD OF IFR VSBYS...DUE IN PART TO WET
GROUND FROM A LATE DAY SHRA. ELSEWHERE...THE FOG THREAT NOT QUITE
AS GREAT. HOWEVER...A BRIEF PERIOD OF LOW VSBYS IS POSSIBLE JUST
BEFORE DAWN.

AM FOG SHOULD BURN OFF BY ARND 13Z TUESDAY. AFTER THAT...THERE IS
A HIGH DEGREE OF CONFIDENCE IN WIDESPREAD VFR CONDS FROM LATE AM
THRU TUE EVENING. HOWEVER...SCT PM TSRA WILL AGAIN BE AN AVIATION
CONCERN. THE BEST CHC OF AN AFTN TSRA AND ACCOMPANYING BRIEF VSBY
REDUCTION WILL BE ACROSS THE N MTNS AND SOUTHWARD ALONG THE LAUREL
HIGHLANDS. HOWEVER...LATEST MDL DATA INDICATES SOME POSSIBILITY OF
A LINE OF TSRA SWEEPING SE ACROSS THE ENTIRE REGION TUE EVENING.

.OUTLOOK...
WED-THU...SCT THUNDERSTORM IMPACTS POSSIBLE...MAINLY IN THE PM.
FRI-SAT...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...LA CORTE/CERU
AVIATION...FITZGERALD

000
FXUS61 KCTP 210355
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1155 PM EDT MON MAY 20 2013

.SYNOPSIS...
A WARM HUMID AIRMASS WILL REMAIN IN PLACE THROUGH MID WEEK.
EXPECT WELL ABOVE NORMAL AFTERNOON TEMPERATURES THROUGH WEDNESDAY
BEFORE A COLD FRONT BRINGS TEMPERATURES BACK BELOW NORMAL WITH
DRIER CONDITIONS FOR THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
THE REGION IS UNDER A WARM AND HUMID AIRMASS SO IT WILL BE A
MUGGY OVERNIGHT. AREAS OF LOW CLOUDS AND PATCHY FOG ARE POSSIBLE
LATE TONIGHT SINCE WILL DEWPOINTS REMAIN HIGH AND WINDS WILL FALL
OFF TO LIGHT AND VARIABLE. CONVECTION OVER LAKE HURON AND SOUTHERN
MICHIGAN CRESTING THE UPPER RIDGE TO OUR WEST COULD SNEAK INTO THE
NW AFTER MIDNIGHT...BUT AT THIS TIME SHORT RANGE HIGH RES MODELS
ARE FORECASTING IT TO DIMINISH RAPIDLY BEFORE IT BECOMES A
PROBLEM. WILL HAVE TO BE WATCHED BUT FOR NOW I JUST HAVE SMALL
CHANCES FOR THUNDERSTORMS OVER NWRN AREAS LATER TONIGHT. MINS WILL
AGAIN BE MUGGY UPPER 50S AND LOWER 60S.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
TUESDAY...WE WILL BE BE WELL INTO THE WARM SECTOR AHEAD OF THE STORM
CRAWLING IN FROM THE NORTHERN PLAINS/MIDWEST/UPPER LAKES. THE WARM
SECTOR AIR WILL BE QUITE WARM FOR THIS TIME OF YEAR...HAVING SPENT
PLENTY OF TIME COOKING OVER THE MS AND OH VALLEYS WITH GOOD GULF
INFLOW. TEMPS THERE RIGHT NOW ARE ABOUT 10F ABOVE AVERAGES.
THEREFORE...SUMMERTIME TEMPS OF UPPER 70S IN THE HILLS TO MID 80S IN
THE VALLEYS ARE EXPECTED ON TUESDAY. ALONG WITH THE WARM
TEMPERATURES...THE DEWPOINTS WILL BE SOLIDLY IN THE 60S. THIS
WARM...MOIST AIR AND A WEAKENING RIDGE MOVING OVERHEAD AND A LITTLE
TO OUR EAST WILL CREATE A GOOD SITUATION FOR SCT AFTN CONVECTION.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
THE LARGE UPPER LEVEL LOW BRINGING SEVERE WEATHER THROUGHOUT THE
MIDWEST WILL SLOWLY MAKE ITS WAY EASTWARD. THIS FLOW SHOULD BRING A
RATHER UNSETTLED PERIOD THROUGH THE WORK WEEK. AS THE UPPER LEVEL
RIDGE CONTINUES TO BREAK DOWN...STORMS WILL SLOWLY APPROACH.  SEVERE
OUTLOOK FOR DAY3/WED HAS THE WESTERN HALF OF THE CWA IN THE SLIGHT
RISK. SOUTHEASTERLY MOISTURE...COUPLED WITH INSTABILITY FROM THE
FRONT AND DAYTIME HIGHS IN THE 80S SHOULD ALLOW FOR A SUFFICIENT
ENVIRONMENT FOR DAYTIME STORMS/SHOWERS. SHEAR SHOULD BE
DECENT...ESPECIALLY AS MID RANGE MODELS ARE HINTING AT A LLJ THROUGH
WEDNESDAY AFTERNOON. THURSDAY WILL AGAIN FEATURE SCT/NMRS TSRA. THE
MED RANGE GUID IS NOW PRETTY SOLID WITH A THURS NIGHT/EARLY FRIDAY
PASSAGE OF THE COLD FRONT ASSOCD WITH THE SYNOPTIC SCALE STORM. MUCH
COOLER AIR AND DRIER CONDITIONS SHOULD FOLLOW FOR THE WEEKEND. ECMWF
HAS BACKED OFF ON THE COLD-NESS OF THE AIR MOVING DOWN WITH THE BIG
1030MB HIGH FOR THE WEEKEND...THOUGH IT LOOKS LIKE THE ZERO C LINE
AT 8H COULD CLIP THE NORTHWESTERN CORNER OF PA. MIN TEMPS FOR
SATURDAY MORNING WILL BE COOL BUT HAVE KEPT THEM IN THE LOW 40S TO
UPPER 30S. DRIER AIR ASSOCIATED WITH THIS FRONT SHOULD KEEP
PRECIPITATION OUT OF THE FORECAST THROUGH THE WEEKEND...WITH WEAK
HIGH PRESSURE BUILDING THROUGH SUNDAY. MEMORIAL DAY MAY SEEM SOME
CLOUDINESS AS THE RIDGE BREAKS DOWN TO DUE NORTHWESTERLY FLOW.
MOISTURE FROM A WEAK SHORTWAVE COULD BRING PRECIPITATION ALONG THE
MASON DIXON MONDAY EVENING...YET DUE TO IT BEING ON THE EDGE OF THE
FORECAST MUCH COULD CHANGE.

&&

.AVIATION /04Z TUESDAY THROUGH SATURDAY/...
THE MAIN AVIATION CONCERN OVERNIGHT IS THE POTENTIAL OF FOG. HIGH
DEWPOINTS AND LIGHT WINDS WILL LEAD TO AREAS OF FOG...MAINLY AFTER
06Z. BULK OF MDL GUIDANCE CONTINUES TO TARGET THE EASTERN THIRD OF
THE STATE FOR THE LOWEST VSBYS DUE TO A NEARLY CALM WIND AND LOWER
DWPT DEPRESSIONS IN THIS AREA. THE COMBINATION OF MDL DATA AND 03Z
SFC DWPT DEPRESSIONS SUGGEST KLNS AND KMDT ARE VERY LIKELY TO
EXPERIENCE A PERIOD OF IFR VSBYS LATE TONIGHT. KAOO ALSO APPEARS
LIKELY TO EXPERIENCE A PERIOD OF IFR VSBYS...DUE IN PART TO WET
GROUND FROM A LATE DAY SHRA. ELSEWHERE...THE FOG THREAT NOT QUITE
AS GREAT. HOWEVER...A BRIEF PERIOD OF LOW VSBYS IS POSSIBLE JUST
BEFORE DAWN.

AM FOG SHOULD BURN OFF BY ARND 13Z TUESDAY. AFTER THAT...THERE IS
A HIGH DEGREE OF CONFIDENCE IN WIDESPREAD VFR CONDS FROM LATE AM
THRU TUE EVENING. HOWEVER...SCT PM TSRA WILL AGAIN BE AN AVIATION
CONCERN. THE BEST CHC OF AN AFTN TSRA AND ACCOMPANYING BRIEF VSBY
REDUCTION WILL BE ACROSS THE N MTNS AND SOUTHWARD ALONG THE LAUREL
HIGHLANDS. HOWEVER...LATEST MDL DATA INDICATES SOME POSSIBILITY OF
A LINE OF TSRA SWEEPING SE ACROSS THE ENTIRE REGION TUE EVENING.

.OUTLOOK...
WED-THU...SCT THUNDERSTORM IMPACTS POSSIBLE...MAINLY IN THE PM.
FRI-SAT...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...LA CORTE/LAMBERT
NEAR TERM...LA CORTE/LAMBERT
SHORT TERM...DANGELO/LAMBERT
LONG TERM...LA CORTE/CERU
AVIATION...FITZGERALD

000
FXUS61 KCTP 210223
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1023 PM EDT MON MAY 20 2013

.SYNOPSIS...
A WARM HUMID AIRMASS WILL REMAIN IN PLACE THROUGH MID WEEK.
EXPECT WELL ABOVE NORMAL AFTERNOON TEMPERATURES THROUGH WEDNESDAY
BEFORE A COLD FRONT BRINGS TEMPERATURES BACK BELOW NORMAL WITH
DRIER CONDITIONS FOR THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...

THE REGION IS UNDER A WARM AND HUMID AIRMASS SO IT WILL BE A
MUGGY OVERNIGHT. AREAS OF LOW CLOUDS AND PATCHY FOG ARE POSSIBLE
LATE TONIGHT SINCE WILL DEWPOINTS REMAIN HIGH AND WINDS WILL FALL
OFF TO LIGHT AND VARIABLE. CONVECTION OVER LAKE HURON AND SOUTHERN
MICHIGAN CRESTING THE UPPER RIDGE TO OUR WEST COULD SNEAK INTO THE
NW AFTER MIDNIGHT...BUT AT THIS TIME SHORT RANGE HIGH RES MODELS
ARE FORECASTING IT TO DIMINISH RAPIDLY BEFORE IT BECOMES A
PROBLEM. WILL HAVE TO BE WATCHED BUT FOR NOW I JUST HAVE SMALL
CHANCES FOR THUNDERSTORMS OVER NWRN AREAS LATER TONIGHT. MINS WILL
AGAIN BE MUGGY UPPER 50S AND LOWER 60S.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
TUESDAY...WE WILL BE BE WELL INTO THE WARM SECTOR AHEAD OF THE STORM
CRAWLING IN FROM THE NORTHERN PLAINS/MIDWEST/UPPER LAKES. THE WARM
SECTOR AIR WILL BE QUITE WARM FOR THIS TIME OF YEAR...HAVING SPENT
PLENTY OF TIME COOKING OVER THE MS AND OH VALLEYS WITH GOOD GULF
INFLOW. TEMPS THERE RIGHT NOW ARE ABOUT 10F ABOVE AVERAGES.
THEREFORE...SUMMERTIME TEMPS OF UPPER 70S IN THE HILLS TO MID 80S IN
THE VALLEYS ARE EXPECTED ON TUESDAY. ALONG WITH THE WARM
TEMPERATURES...THE DEWPOINTS WILL BE SOLIDLY IN THE 60S. THIS
WARM...MOIST AIR AND A WEAKENING RIDGE MOVING OVERHEAD AND A LITTLE
TO OUR EAST WILL CREATE A GOOD SITUATION FOR SCT AFTN CONVECTION.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
THE LARGE UPPER LEVEL LOW BRINGING SEVERE WEATHER THROUGHOUT THE
MIDWEST WILL SLOWLY MAKE ITS WAY EASTWARD. THIS FLOW SHOULD BRING A
RATHER UNSETTLED PERIOD THROUGH THE WORK WEEK. AS THE UPPER LEVEL
RIDGE CONTINUES TO BREAK DOWN...STORMS WILL SLOWLY APPROACH.  SEVERE
OUTLOOK FOR DAY3/WED HAS THE WESTERN HALF OF THE CWA IN THE SLIGHT
RISK. SOUTHEASTERLY MOISTURE...COUPLED WITH INSTABILITY FROM THE
FRONT AND DAYTIME HIGHS IN THE 80S SHOULD ALLOW FOR A SUFFICIENT
ENVIRONMENT FOR DAYTIME STORMS/SHOWERS. SHEAR SHOULD BE
DECENT...ESPECIALLY AS MID RANGE MODELS ARE HINTING AT A LLJ THROUGH
WEDNESDAY AFTERNOON. THURSDAY WILL AGAIN FEATURE SCT/NMRS TSRA. THE
MED RANGE GUID IS NOW PRETTY SOLID WITH A THURS NIGHT/EARLY FRIDAY
PASSAGE OF THE COLD FRONT ASSOCD WITH THE SYNOPTIC SCALE STORM. MUCH
COOLER AIR AND DRIER CONDITIONS SHOULD FOLLOW FOR THE WEEKEND. ECMWF
HAS BACKED OFF ON THE COLD-NESS OF THE AIR MOVING DOWN WITH THE BIG
1030MB HIGH FOR THE WEEKEND...THOUGH IT LOOKS LIKE THE ZERO C LINE
AT 8H COULD CLIP THE NORTHWESTERN CORNER OF PA. MIN TEMPS FOR
SATURDAY MORNING WILL BE COOL BUT HAVE KEPT THEM IN THE LOW 40S TO
UPPER 30S. DRIER AIR ASSOCIATED WITH THIS FRONT SHOULD KEEP
PRECIPITATION OUT OF THE FORECAST THROUGH THE WEEKEND...WITH WEAK
HIGH PRESSURE BUILDING THROUGH SUNDAY. MEMORIAL DAY MAY SEEM SOME
CLOUDINESS AS THE RIDGE BREAKS DOWN TO DUE NORTHWESTERLY FLOW.
MOISTURE FROM A WEAK SHORTWAVE COULD BRING PRECIPITATION ALONG THE
MASON DIXON MONDAY EVENING...YET DUE TO IT BEING ON THE EDGE OF THE
FORECAST MUCH COULD CHANGE.

&&

.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
EARLY EVENING RADAR LOOP SHOWS EARLIER SHRA/TSRA OVR THE LAUREL
HIGHLANDS HAVE DISSIPATED AND CU SHOWING SIGNS OF COLLAPSE AS BLYR
COOLS/STABILIZES.

THE MAIN AVIATION CONCERN OVERNIGHT IS THE POTENTIAL OF FOG. HIGH
DEWPOINTS AND LIGHT WINDS WILL LEAD TO AREAS OF FOG...MAINLY AFTER
06Z. BULK OF MDL GUIDANCE CONTINUES TO TARGET THE EASTERN THIRD
OF THE STATE FOR THE LOWEST /LIKELY BLW 1SM/ VSBYS...DUE TO A
NEARLY CALM WIND AND LOWER DWPT DEPRESSIONS IN THIS AREA. THE
COMBINATION OF MDL DATA AND 00Z SFC DWPT DEPRESSIONS SUGGESTS KLNS
IS VERY LIKELY TO EXPERIENCE A PERIOD OF IFR/LIFR VSBYS LATE
TONIGHT. KAOO ALSO APPEARS VERY LIKELY TO EXPERIENCE A PERIOD OF
IFR VSBYS...DUE TO THE WET GROUND FROM A LATE DAY SHRA. ELSEWHERE...THE
FOG THREAT NOT QUITE AS GREAT. HOWEVER...A BRIEF PERIOD OF LOW
VSBYS IS POSSIBLE JUST BEFORE DAWN.

AM FOG SHOULD BURN OFF BY ARND 13Z TUESDAY. AFTER THAT...THERE IS
A HIGH DEGREE OF CONFIDENCE IN WIDESPREAD VFR CONDS FROM LATE AM
THRU TUE EVENING. HOWEVER...SCT PM TSRA WILL AGAIN BE AN AVIATION
CONCERN. THE BEST CHC OF AN AFTN TSRA AND ACCOMPANYING BRIEF VSBY
REDUCTION WILL BE ACROSS THE N MTNS AND SOUTHWARD ALONG THE LAUREL
HIGHLANDS. HOWEVER...LATEST MDL DATA INDICATES SOME POSSIBILITY OF
A LINE OF TSRA SWEEPING SE ACROSS THE ENTIRE REGION TUE EVENING.

.OUTLOOK...
WED-THU...SCT THUNDERSTORM IMPACTS POSSIBLE...MAINLY IN THE PM.
FRI-SAT...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...LA CORTE/LAMBERT
NEAR TERM...LA CORTE/LAMBERT
SHORT TERM...DANGELO/LAMBERT
LONG TERM...LA CORTE/CERU
AVIATION...FITZGERALD

000
FXUS61 KCTP 210041
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
841 PM EDT MON MAY 20 2013

.SYNOPSIS...
A WARM HUMID AIRMASS WILL REMAIN IN PLACE THROUGH MID WEEK.
EXPECT WELL ABOVE NORMAL AFTERNOON TEMPERATURES THROUGH WEDNESDAY
BEFORE A COLD FRONT BRINGS TEMPERATURES BACK BELOW NORMAL WITH
DRIER CONDITIONS FOR THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
DIURNAL CONVECTION THAT FIRED OVER THE HIGHLANDS OF THE SOUTHWEST
HAS ALL BUT VANISHED WITH LOWERING SUN ANGLES. THE REGION IS UNDER
A WARM AND HUMID AIRMASS SO IT WILL BE A MUGGY OVERNIGHT WITH SOME
PATCHY FOG AFTER MIDNIGHT.

CONVECTION CURRENTLY RACING EAST OVER IS FORECAST BY THE SHORT
RANGE HIGH RES MODELS TO DIE BEFORE IT MOVES INTO NW PA AROUND
MIDNIGHT...BUT NEEDS TO BE WATCHED.

AREAS OF LOW CLOUDS AND PATCHY FOG ARE POSSIBLE LATE TONIGHT
SINCE WILL DEWPOINTS REMAIN HIGH AND WINDS WILL FALL OFF TO LIGHT
AND VARIABLE. CONVECTION OVER LAKE HURON AND SOUTHERN MICHIGAN
CRESTING THE UPPER RIDGE TO OUR WEST COULD SNEAK INTO THE NW AFTER
MIDNIGHT...BUT AT THIS TIME SHORT RANGE HIGH RES MODELS ARE
FORECASTING IT TO DIMINISH RAPIDLY BEFORE IT BECOMES A PROBLEM.
WILL HAVE TO BE WATCHED BUT FOR NOW I JUST HAVE SMALL CHANCES FOR
THUNDERSTORMS OVER NWRN AREAS LATER TONIGHT. MINS WILL AGAIN BE
MUGGY UPPER 50S AND LOWER 60S.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
TUESDAY...WE WILL BE BE WELL INTO THE WARM SECTOR AHEAD OF THE STORM
CRAWLING IN FROM THE NORTHERN PLAINS/MIDWEST/UPPER LAKES. THE WARM
SECTOR AIR WILL BE QUITE WARM FOR THIS TIME OF YEAR...HAVING SPENT
PLENTY OF TIME COOKING OVER THE MS AND OH VALLEYS WITH GOOD GULF
INFLOW. TEMPS THERE RIGHT NOW ARE ABOUT 10F ABOVE AVERAGES.
THEREFORE...SUMMERTIME TEMPS OF UPPER 70S IN THE HILLS TO MID 80S IN
THE VALLEYS ARE EXPECTED ON TUESDAY. ALONG WITH THE WARM
TEMPERATURES...THE DEWPOINTS WILL BE SOLIDLY IN THE 60S. THIS
WARM...MOIST AIR AND A WEAKENING RIDGE MOVING OVERHEAD AND A LITTLE
TO OUR EAST WILL CREATE A GOOD SITUATION FOR SCT AFTN CONVECTION.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
THE LARGE UPPER LEVEL LOW BRINGING SEVERE WEATHER THROUGHOUT THE
MIDWEST WILL SLOWLY MAKE ITS WAY EASTWARD. THIS FLOW SHOULD BRING A
RATHER UNSETTLED PERIOD THROUGH THE WORK WEEK. AS THE UPPER LEVEL
RIDGE CONTINUES TO BREAK DOWN...STORMS WILL SLOWLY APPROACH.  SEVERE
OUTLOOK FOR DAY3/WED HAS THE WESTERN HALF OF THE CWA IN THE SLIGHT
RISK. SOUTHEASTERLY MOISTURE...COUPLED WITH INSTABILITY FROM THE
FRONT AND DAYTIME HIGHS IN THE 80S SHOULD ALLOW FOR A SUFFICIENT
ENVIRONMENT FOR DAYTIME STORMS/SHOWERS. SHEAR SHOULD BE
DECENT...ESPECIALLY AS MID RANGE MODELS ARE HINTING AT A LLJ THROUGH
WEDNESDAY AFTERNOON. THURSDAY WILL AGAIN FEATURE SCT/NMRS TSRA. THE
MED RANGE GUID IS NOW PRETTY SOLID WITH A THURS NIGHT/EARLY FRIDAY
PASSAGE OF THE COLD FRONT ASSOCD WITH THE SYNOPTIC SCALE STORM. MUCH
COOLER AIR AND DRIER CONDITIONS SHOULD FOLLOW FOR THE WEEKEND. ECMWF
HAS BACKED OFF ON THE COLD-NESS OF THE AIR MOVING DOWN WITH THE BIG
1030MB HIGH FOR THE WEEKEND...THOUGH IT LOOKS LIKE THE ZERO C LINE
AT 8H COULD CLIP THE NORTHWESTERN CORNER OF PA. MIN TEMPS FOR
SATURDAY MORNING WILL BE COOL BUT HAVE KEPT THEM IN THE LOW 40S TO
UPPER 30S. DRIER AIR ASSOCIATED WITH THIS FRONT SHOULD KEEP
PRECIPITATION OUT OF THE FORECAST THROUGH THE WEEKEND...WITH WEAK
HIGH PRESSURE BUILDING THROUGH SUNDAY. MEMORIAL DAY MAY SEEM SOME
CLOUDINESS AS THE RIDGE BREAKS DOWN TO DUE NORTHWESTERLY FLOW.
MOISTURE FROM A WEAK SHORTWAVE COULD BRING PRECIPITATION ALONG THE
MASON DIXON MONDAY EVENING...YET DUE TO IT BEING ON THE EDGE OF THE
FORECAST MUCH COULD CHANGE.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
EARLY EVENING RADAR LOOP SHOWS EARLIER SHRA/TSRA OVR THE LAUREL
HIGHLANDS HAVE DISSIPATED AND CU SHOWING SIGNS OF COLLAPSE AS BLYR
COOLS/STABILIZES.

THE MAIN AVIATION CONCERN OVERNIGHT IS THE POTENTIAL OF FOG. HIGH
DEWPOINTS AND LIGHT WINDS WILL LEAD TO AREAS OF FOG...MAINLY AFTER
06Z. BULK OF MDL GUIDANCE CONTINUES TO TARGET THE EASTERN THIRD
OF THE STATE FOR THE LOWEST /LIKELY BLW 1SM/ VSBYS...DUE TO A
NEARLY CALM WIND AND LOWER DWPT DEPRESSIONS IN THIS AREA. THE
COMBINATION OF MDL DATA AND 00Z SFC DWPT DEPRESSIONS SUGGESTS KLNS
IS VERY LIKELY TO EXPERIENCE A PERIOD OF IFR/LIFR VSBYS LATE
TONIGHT. KAOO ALSO APPEARS VERY LIKELY TO EXPERIENCE A PERIOD OF
IFR VSBYS...DUE TO THE WET GROUND FROM A LATE DAY SHRA. ELSEWHERE...THE
FOG THREAT NOT QUITE AS GREAT. HOWEVER...A BRIEF PERIOD OF LOW
VSBYS IS POSSIBLE JUST BEFORE DAWN.

AM FOG SHOULD BURN OFF BY ARND 13Z TUESDAY. AFTER THAT...THERE IS
A HIGH DEGREE OF CONFIDENCE IN WIDESPREAD VFR CONDS FROM LATE AM
THRU TUE EVENING. HOWEVER...SCT PM TSRA WILL AGAIN BE AN AVIATION
CONCERN. THE BEST CHC OF AN AFTN TSRA AND ACCOMPANYING BRIEF VSBY
REDUCTION WILL BE ACROSS THE N MTNS AND SOUTHWARD ALONG THE LAUREL
HIGHLANDS. HOWEVER...LATEST MDL DATA INDICATES SOME POSSIBILITY OF
A LINE OF TSRA SWEEPING SE ACROSS THE ENTIRE REGION TUE EVENING.

.OUTLOOK...
WED-THU...SCT THUNDERSTORM IMPACTS POSSIBLE...MAINLY IN THE PM.
FRI-SAT...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...LA CORTE/LAMBERT
NEAR TERM...LA CORTE/LAMBERT
SHORT TERM...DANGELO/LAMBERT
LONG TERM...LA CORTE/CERU
AVIATION...FITZGERALD

000
FXUS61 KCTP 210036
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
738 PM EDT MON MAY 20 2013

.SYNOPSIS...

A WARM HUMID AIRMASS WILL REMAIN IN PLACE THROUGH MID WEEK.
EXPECT WELL ABOVE NORMAL AFTERNOON TEMPERATURES THROUGH WEDNESDAY
BEFORE A COLD FRONT BRINGS TEMPERATURES BACK BELOW NORMAL WITH
DRIER CONDITIONS FOR THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...

DIURNAL CONVECTION THAT FIRED OVER THE HIGHLANDS OF THE SOUTHWEST
HAS ALL BUT VANISHED WITH LOWERING SUN ANGLES. THE REGION IS UNDER
A WARM AND HUMID AIRMASS SO IT WILL BE A MUGGY OVERNIGHT WITH SOME
PATCHY FOG AFTER MIDNIGHT.

AREAS OF LOW CLOUDS AND PATCHY FOG ARE POSSIBLE LATE TONIGHT SINCE
WILL DEWPOINTS REMAIN HIGH AND WINDS WILL FALL OFF TO LIGHT AND
VARIABLE. CONVECTION OVER LAKE HURON AND SOUTHERN MICHIGAN CRESTING
THE UPPER RIDGE TO OUR WEST COULD SNEAK INTO THE NW AFTER
MIDNIGHT...BUT AT THIS TIME SHORT RANGE HIGH RES MODELS ARE
FORECASTING IT TO DIMINISH RAPIDLY BEFORE IT BECOMES A PROBLEM. WILL
HAVE TO BE WATCHED BUT FOR NOW I JUST HAVE SMALL CHANCES FOR
THUNDERSTORMS OVER NWRN AREAS LATER TONIGHT. MINS WILL AGAIN BE
MUGGY UPPER 50S AND LOWER 60S.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...

TUESDAY...WE WILL BE BE WELL INTO THE WARM SECTOR AHEAD OF THE STORM
CRAWLING IN FROM THE NORTHERN PLAINS/MIDWEST/UPPER LAKES. THE WARM
SECTOR AIR WILL BE QUITE WARM FOR THIS TIME OF YEAR...HAVING SPENT
PLENTY OF TIME COOKING OVER THE MS AND OH VALLEYS WITH GOOD GULF
INFLOW. TEMPS THERE RIGHT NOW ARE ABOUT 10F ABOVE AVERAGES.
THEREFORE...SUMMERTIME TEMPS OF UPPER 70S IN THE HILLS TO MID 80S IN
THE VALLEYS ARE EXPECTED ON TUESDAY. ALONG WITH THE WARM
TEMPERATURES...THE DEWPOINTS WILL BE SOLIDLY IN THE 60S. THIS
WARM...MOIST AIR AND A WEAKENING RIDGE MOVING OVERHEAD AND A LITTLE
TO OUR EAST WILL CREATE A GOOD SITUATION FOR SCT AFTN CONVECTION.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
THE LARGE UPPER LEVEL LOW BRINGING SEVERE WEATHER THROUGHOUT THE
MIDWEST WILL SLOWLY MAKE ITS WAY EASTWARD. THIS FLOW SHOULD BRING A
RATHER UNSETTLED PERIOD THROUGH THE WORK WEEK. AS THE UPPER LEVEL
RIDGE CONTINUES TO BREAK DOWN...STORMS WILL SLOWLY APPROACH.  SEVERE
OUTLOOK FOR DAY3/WED HAS THE WESTERN HALF OF THE CWA IN THE SLIGHT
RISK. SOUTHEASTERLY MOISTURE...COUPLED WITH INSTABILITY FROM THE
FRONT AND DAYTIME HIGHS IN THE 80S SHOULD ALLOW FOR A SUFFICIENT
ENVIRONMENT FOR DAYTIME STORMS/SHOWERS. SHEAR SHOULD BE
DECENT...ESPECIALLY AS MID RANGE MODELS ARE HINTING AT A LLJ THROUGH
WEDNESDAY AFTERNOON. THURSDAY WILL AGAIN FEATURE SCT/NMRS TSRA. THE
MED RANGE GUID IS NOW PRETTY SOLID WITH A THURS NIGHT/EARLY FRIDAY
PASSAGE OF THE COLD FRONT ASSOCD WITH THE SYNOPTIC SCALE STORM. MUCH
COOLER AIR AND DRIER CONDITIONS SHOULD FOLLOW FOR THE WEEKEND. ECMWF
HAS BACKED OFF ON THE COLD-NESS OF THE AIR MOVING DOWN WITH THE BIG
1030MB HIGH FOR THE WEEKEND...THOUGH IT LOOKS LIKE THE ZERO C LINE
AT 8H COULD CLIP THE NORTHWESTERN CORNER OF PA. MIN TEMPS FOR
SATURDAY MORNING WILL BE COOL BUT HAVE KEPT THEM IN THE LOW 40S TO
UPPER 30S. DRIER AIR ASSOCIATED WITH THIS FRONT SHOULD KEEP
PRECIPITATION OUT OF THE FORECAST THROUGH THE WEEKEND...WITH WEAK
HIGH PRESSURE BUILDING THROUGH SUNDAY. MEMORIAL DAY MAY SEEM SOME
CLOUDINESS AS THE RIDGE BREAKS DOWN TO DUE NORTHWESTERLY FLOW.
MOISTURE FROM A WEAK SHORTWAVE COULD BRING PRECIPITATION ALONG THE
MASON DIXON MONDAY EVENING...YET DUE TO IT BEING ON THE EDGE OF THE
FORECAST MUCH COULD CHANGE.

&&

.AVIATION /23Z MONDAY THROUGH SATURDAY/...
LATE AFTN RADAR LOOP SHOWING A FEW SHRA/TSRA HAVE DEVELOPED OVR
THE LAUREL HIGHLANDS. A BRIEF VSBY REDUCTION IS POSSIBLE AT
AOO/JST/UNV THRU ARND 00Z. ANY REMAINING SHRA/TSRA SHOULD
DISSIPATE AFTER SUNSET...AS BLYR COOLS/STABILIZES.

HIGH DEWPOINTS AND LIGHT WINDS WILL LEAD TO AREAS OF FOG AFTER
06Z TUESDAY. BULK OF MDL GUIDANCE TARGETS THE EASTERN HALF OF THE
STATE FOR THE LOWEST /LIKELY BLW 1SM/ VSBYS...DUE TO A NEARLY CALM
WIND.

AM FOG SHOULD BURN OFF BTWN 13-16Z TUESDAY. HOWEVER...PM TSRA WILL
AGAIN BE AN AVIATION CONCERN. THE BEST CHC OF A TSRA AND
ACCOMPANYING BRIEF VSBY REDUCTION WILL BE DURING THE PM HOURS
ACROSS THE N MTNS AND SOUTHWARD ALONG THE LAUREL HIGHLANDS.

.OUTLOOK...
TUE-THU...LOW CLOUDS/FOG POSS EARLY. SCT PM THUNDERSTORM IMPACTS
POSSIBLE.
FRI AND SAT...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...LA CORTE/LAMBERT
NEAR TERM...LA CORTE/LAMBERT
SHORT TERM...DANGELO/LAMBERT
LONG TERM...LA CORTE/CERU
AVIATION...FITZGERALD/LAMBERT

000
FXUS61 KCTP 202338
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
738 PM EDT MON MAY 20 2013

.SYNOPSIS...

A WARM HUMID AIRMASS WILL REMAIN IN PLACE THROUGH MID WEEK.
EXPECT WELL ABOVE NORMAL AFTERNOON TEMPERATURES THROUGH WEDNESDAY
BEFORE A COLD FRONT BRINGS TEMPERATURES BACK BELOW NORMAL WITH
DRIER CONDITIONS FOR THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...

DIURNAL CONVECTION THAT FIRED OVER THE HIGHLANDS OF THE SOUTHWEST
HAS ALL BUT VANISHED WITH LOWERING SUN ANGLES. THE REGION IS UNDER
A WARM AND HUMID AIRMASS SO IT WILL BE A MUGGY OVERNIGHT WITH SOME
PATCHY FOG AFTER MIDNIGHT.

CONVECTION CURRENTLY RACING EAST OVER IS FORECAST BY THE SHORT
RANGE HIGH RES MODELS TO DIE BEFORE IT MOVES INTO NW PA AROUND
MIDNIGHT...BUT NEEDS TO BE WATCHED.

AREAS OF LOW CLOUDS AND PATCHY FOG ARE POSSIBLE LATE TONIGHT
SINCE WILL DEWPOINTS REMAIN HIGH AND WINDS WILL FALL OFF TO LIGHT
AND VARIABLE. CONVECTION OVER LAKE HURON AND SOUTHERN MICHIGAN
CRESTING THE UPPER RIDGE TO OUR WEST COULD SNEAK INTO THE NW AFTER
MIDNIGHT...BUT AT THIS TIME SHORT RANGE HIGH RES MODELS ARE
FORECASTING IT TO DIMINISH RAPIDLY BEFORE IT BECOMES A PROBLEM.
WILL HAVE TO BE WATCHED BUT FOR NOW I JUST HAVE SMALL CHANCES FOR
THUNDERSTORMS OVER NWRN AREAS LATER TONIGHT. MINS WILL AGAIN BE
MUGGY UPPER 50S AND LOWER 60S.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...

TUESDAY...WE WILL BE BE WELL INTO THE WARM SECTOR AHEAD OF THE STORM
CRAWLING IN FROM THE NORTHERN PLAINS/MIDWEST/UPPER LAKES. THE WARM
SECTOR AIR WILL BE QUITE WARM FOR THIS TIME OF YEAR...HAVING SPENT
PLENTY OF TIME COOKING OVER THE MS AND OH VALLEYS WITH GOOD GULF
INFLOW. TEMPS THERE RIGHT NOW ARE ABOUT 10F ABOVE AVERAGES.
THEREFORE...SUMMERTIME TEMPS OF UPPER 70S IN THE HILLS TO MID 80S IN
THE VALLEYS ARE EXPECTED ON TUESDAY. ALONG WITH THE WARM
TEMPERATURES...THE DEWPOINTS WILL BE SOLIDLY IN THE 60S. THIS
WARM...MOIST AIR AND A WEAKENING RIDGE MOVING OVERHEAD AND A LITTLE
TO OUR EAST WILL CREATE A GOOD SITUATION FOR SCT AFTN CONVECTION.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
THE LARGE UPPER LEVEL LOW BRINGING SEVERE WEATHER THROUGHOUT THE
MIDWEST WILL SLOWLY MAKE ITS WAY EASTWARD. THIS FLOW SHOULD BRING A
RATHER UNSETTLED PERIOD THROUGH THE WORK WEEK. AS THE UPPER LEVEL
RIDGE CONTINUES TO BREAK DOWN...STORMS WILL SLOWLY APPROACH.  SEVERE
OUTLOOK FOR DAY3/WED HAS THE WESTERN HALF OF THE CWA IN THE SLIGHT
RISK. SOUTHEASTERLY MOISTURE...COUPLED WITH INSTABILITY FROM THE
FRONT AND DAYTIME HIGHS IN THE 80S SHOULD ALLOW FOR A SUFFICIENT
ENVIRONMENT FOR DAYTIME STORMS/SHOWERS. SHEAR SHOULD BE
DECENT...ESPECIALLY AS MID RANGE MODELS ARE HINTING AT A LLJ THROUGH
WEDNESDAY AFTERNOON. THURSDAY WILL AGAIN FEATURE SCT/NMRS TSRA. THE
MED RANGE GUID IS NOW PRETTY SOLID WITH A THURS NIGHT/EARLY FRIDAY
PASSAGE OF THE COLD FRONT ASSOCD WITH THE SYNOPTIC SCALE STORM. MUCH
COOLER AIR AND DRIER CONDITIONS SHOULD FOLLOW FOR THE WEEKEND. ECMWF
HAS BACKED OFF ON THE COLD-NESS OF THE AIR MOVING DOWN WITH THE BIG
1030MB HIGH FOR THE WEEKEND...THOUGH IT LOOKS LIKE THE ZERO C LINE
AT 8H COULD CLIP THE NORTHWESTERN CORNER OF PA. MIN TEMPS FOR
SATURDAY MORNING WILL BE COOL BUT HAVE KEPT THEM IN THE LOW 40S TO
UPPER 30S. DRIER AIR ASSOCIATED WITH THIS FRONT SHOULD KEEP
PRECIPITATION OUT OF THE FORECAST THROUGH THE WEEKEND...WITH WEAK
HIGH PRESSURE BUILDING THROUGH SUNDAY. MEMORIAL DAY MAY SEEM SOME
CLOUDINESS AS THE RIDGE BREAKS DOWN TO DUE NORTHWESTERLY FLOW.
MOISTURE FROM A WEAK SHORTWAVE COULD BRING PRECIPITATION ALONG THE
MASON DIXON MONDAY EVENING...YET DUE TO IT BEING ON THE EDGE OF THE
FORECAST MUCH COULD CHANGE.

&&

.AVIATION /23Z MONDAY THROUGH SATURDAY/...
LATE AFTN RADAR LOOP SHOWING A FEW SHRA/TSRA HAVE DEVELOPED OVR
THE LAUREL HIGHLANDS. A BRIEF VSBY REDUCTION IS POSSIBLE AT
AOO/JST/UNV THRU ARND 00Z. ANY REMAINING SHRA/TSRA SHOULD
DISSIPATE AFTER SUNSET...AS BLYR COOLS/STABILIZES.

HIGH DEWPOINTS AND LIGHT WINDS WILL LEAD TO AREAS OF FOG AFTER
06Z TUESDAY. BULK OF MDL GUIDANCE TARGETS THE EASTERN HALF OF THE
STATE FOR THE LOWEST /LIKELY BLW 1SM/ VSBYS...DUE TO A NEARLY CALM
WIND.

AM FOG SHOULD BURN OFF BTWN 13-16Z TUESDAY. HOWEVER...PM TSRA WILL
AGAIN BE AN AVIATION CONCERN. THE BEST CHC OF A TSRA AND
ACCOMPANYING BRIEF VSBY REDUCTION WILL BE DURING THE PM HOURS
ACROSS THE N MTNS AND SOUTHWARD ALONG THE LAUREL HIGHLANDS.

.OUTLOOK...
TUE-THU...LOW CLOUDS/FOG POSS EARLY. SCT PM THUNDERSTORM IMPACTS
POSSIBLE.
FRI AND SAT...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...LA CORTE/LAMBERT
NEAR TERM...LA CORTE/LAMBERT
SHORT TERM...DANGELO/LAMBERT
LONG TERM...LA CORTE/CERU
AVIATION...FITZGERALD/LAMBERT

000
FXUS61 KCTP 202116
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
516 PM EDT MON MAY 20 2013

.SYNOPSIS...
A WARM FRONT WILL MOVE SLOWLY NORTHEAST ACROSS THE STATE THIS
AFTERNOON AND EVENING. INCREASING WARMTH AND HUMIDITY WILL
OVERSPREAD THE REGION THROUGH THE MID-WEEK IN THE WAKE OF THIS
FRONT. EXPECT WELL ABOVE NORMAL AFTERNOON TEMPERATURES ACROSS THE
WESTERN HALF OF THE STATE THIS AFTERNOON...AND IN ALL AREAS TUESDAY
AND WEDNESDAY. TEMPERATURES WILL COOL BACK BELOW NORMAL WITH DRIER
CONDITIONS BY THE WEEKEND AS A VERY COLD AIRMASS DROPS OUT OF
CENTRAL CANADA INTO THE GREAT LAKES AND NORTHEASTERN UNITED STATES.

&&

.NEAR TERM /UNTIL 10 PM THIS EVENING/...
EARLIER LOW STRATUS HAS TRANSITIONED INTO WIDESPREAD SCT-BKN FAIRLY
SHALLOW CU/STRATO CU FIELD ACROSS THE CWA AT MID AFTERNOON.

A RIBBON OF CONVECTION /NO THUNDER YET/ WAS DEVELOPING ACROSS THE
LAUREL WHERE EARLIER CLEARING AND HI LEVEL HEATING HAS RAMPED UP
MIXED LAYER CAPES TO AROUND 1500 J/KG. WARMING ALOFT SHOULD KEEP ANY
TSRA RATHER LOW-TOPPED AND ISOLATED LATE TODAY.

TEMPS ACROSS THE CENTRAL AND WEST ARE RIGHT AROUND THEIR FCST HIGHS
IN THE UPPER 70S TO LOWER 80S FOR HIGHS...AND SLIGHTLY COOLER IN THE
MID 70S ACROSS THE EAST. A FEW SPOTS IN SCENT PENN /JUST EAST OF THE
LAURELS/ COULD TOUCH 85F WHERE THE  MEAN...DOWNSLOPING SWRLY LLVL
FLOW MAXIMIZING THE ADIABATIC WARMING OF THE 14C AIR RESIDING AT THE
850 MB LEVEL.

ALTHOUGH ALL MDL SOUNDINGS CONTINUE TO INDICATE THE ISOLD/SCT SHRA
THAT ARE SEEN FORMING OVER THE PAST HOUR OR SO...IN THE SRN TIER AND
ANOTHER AREA OVER THE NWRN MTS...BROADLY DIVERGENT LLVL FLOW WILL
ACT TO NEGATE ANY ORGANIZED AREAS OF DEEP CONVECTION THROUGH THE
REST OF THE DAYLIGHT HOURS.

WILL INCREASE POPS TO HIGH CHC/ LOW LIKELY ACROSS THE SW MTNS ...BUT
CONTINUE TO KEEP POPS OVER THE NE HALF OF THE CWA BELOW 20 PERCENT.

&&

.SHORT TERM /10 PM THIS EVENING THROUGH 6 PM TUESDAY/...
MORE LOW STRATUS AND FOG ARE LIKELY LATE TONIGHT SINCE WILL
DEWPOINTS REMAIN HIGH AND WINDS WILL FALL OFF TO LIGHT AND VARIABLE.
WILL COUNT ON A FEW DEG C OF WARMING ALOFT AND LACK OF LLVL FORCING
IN THE WAKE OF THE SLOWLY NWD LIFTING WARM FRONT TO QUICKLY
DISSIPATE ANY LINGERING SHOWERS/STORMS THIS EVENING...AND LEAVE POPS
LESS THAN 20 PCT FOR THE BULK OF THE NIGHT. INCREASING CONVECTION
/OVER WRN LOWER MICHIGAN ATTM/ CRESTING THE UPPER RIDGE TO OUR WEST
COULD SNEAK INTO THE NW BY MORNING...BUT THIS IS JUST WORTH A LOW
CHC POP AT THIS POINT. MINS WILL AGAIN BE MUGGY UPPER 50S AND LOWER
60S.

TUESDAY...WE WILL BE BE WELL INTO THE WARM SECTOR AHEAD OF THE STORM
CRAWLING IN FROM THE NORTHERN PLAINS/MIDWEST/UPPER LAKES. THE WARM
SECTOR AIR WILL BE QUITE WARM FOR THIS TIME OF YEAR...HAVING SPENT
PLENTY OF TIME COOKING OVER THE MS AND OH VALLEYS WITH GOOD GULF
INFLOW. TEMPS THERE RIGHT NOW ARE ABOUT 10F ABOVE AVERAGES.
THEREFORE...SUMMERTIME TEMPS OF UPPER 70S IN THE HILLS TO MID 80S IN
THE VALLEYS ARE EXPECTED ON TUESDAY. ALONG WITH THE WARM
TEMPERATURES...THE DEWPOINTS WILL BE SOLIDLY IN THE 60S. THIS
WARM...MOIST AIR AND A WEAKENING RIDGE MOVING OVERHEAD AND A LITTLE
TO OUR EAST WILL CREATE A GOOD SITUATION FOR SCT AFTN CONVECTION.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
THE LARGE UPPER LEVEL LOW BRINGING SEVERE WEATHER THROUGHOUT THE
MIDWEST WILL SLOWLY MAKE ITS WAY EASTWARD. THIS FLOW SHOULD BRING A
RATHER UNSETTLED PERIOD THROUGH THE WORK WEEK. AS THE UPPER LEVEL
RIDGE CONTINUES TO BREAK DOWN...STORMS WILL SLOWLY APPROACH.  SEVERE
OUTLOOK FOR DAY3/WED HAS THE WESTERN HALF OF THE CWA IN THE SLIGHT
RISK. SOUTHEASTERLY MOISTURE...COUPLED WITH INSTABILITY FROM THE
FRONT AND DAYTIME HIGHS IN THE 80S SHOULD ALLOW FOR A SUFFICIENT
ENVIRONMENT FOR DAYTIME STORMS/SHOWERS. SHEAR SHOULD BE
DECENT...ESPECIALLY AS MID RANGE MODELS ARE HINTING AT A LLJ THROUGH
WEDNESDAY AFTERNOON. THURSDAY WILL AGAIN FEATURE SCT/NMRS TSRA. THE
MED RANGE GUID IS NOW PRETTY SOLID WITH A THURS NIGHT/EARLY FRIDAY
PASSAGE OF THE COLD FRONT ASSOCD WITH THE SYNOPTIC SCALE STORM. MUCH
COOLER AIR AND DRIER CONDITIONS SHOULD FOLLOW FOR THE WEEKEND. ECMWF
HAS BACKED OFF ON THE COLD-NESS OF THE AIR MOVING DOWN WITH THE BIG
1030MB HIGH FOR THE WEEKEND...THOUGH IT LOOKS LIKE THE ZERO C LINE
AT 8H COULD CLIP THE NORTHWESTERN CORNER OF PA. MIN TEMPS FOR
SATURDAY MORNING WILL BE COOL BUT HAVE KEPT THEM IN THE LOW 40S TO
UPPER 30S. DRIER AIR ASSOCIATED WITH THIS FRONT SHOULD KEEP
PRECIPITATION OUT OF THE FORECAST THROUGH THE WEEKEND...WITH WEAK
HIGH PRESSURE BUILDING THROUGH SUNDAY. MEMORIAL DAY MAY SEEM SOME
CLOUDINESS AS THE RIDGE BREAKS DOWN TO DUE NORTHWESTERLY FLOW.
MOISTURE FROM A WEAK SHORTWAVE COULD BRING PRECIPITATION ALONG THE
MASON DIXON MONDAY EVENING...YET DUE TO IT BEING ON THE EDGE OF THE
FORECAST MUCH COULD CHANGE.

&&

.AVIATION /21Z MONDAY THROUGH SATURDAY/...
LATE AFTN RADAR LOOP SHOWING A FEW SHRA/TSRA HAVE DEVELOPED OVR
THE LAUREL HIGHLANDS. A BRIEF VSBY REDUCTION IS POSSIBLE AT
AOO/JST/UNV THRU ARND 00Z. ANY REMAINING SHRA/TSRA SHOULD
DISSIPATE AFTER SUNSET...AS BLYR COOLS/STABILIZES.

HIGH DEWPOINTS AND LIGHT WINDS WILL LEAD TO AREAS OF FOG AFTER
06Z TUESDAY. BULK OF MDL GUIDANCE TARGETS THE EASTERN HALF OF THE
STATE FOR THE LOWEST /LIKELY BLW 1SM/ VSBYS...DUE TO A NEARLY CALM
WIND.

AM FOG SHOULD BURN OFF BTWN 13-16Z TUESDAY. HOWEVER...PM TSRA WILL
AGAIN BE AN AVIATION CONCERN. THE BEST CHC OF A TSRA AND
ACCOMPANYING BRIEF VSBY REDUCTION WILL BE DURING THE PM HOURS
ACROSS THE N MTNS AND SOUTHWARD ALONG THE LAUREL HIGHLANDS.

.OUTLOOK...
TUE-THU...LOW CLOUDS/FOG POSS EARLY. SCT PM THUNDERSTORM IMPACTS
POSSIBLE.
FRI AND SAT...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...DANGELO/LAMBERT
LONG TERM...LA CORTE/CERU
AVIATION...FITZGERALD/LAMBERT

000
FXUS61 KCTP 201917
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
316 PM EDT MON MAY 20 2013

.SYNOPSIS...
A WARM FRONT WILL MOVE SLOWLY NORTHEAST ACROSS THE STATE THIS
AFTERNOON AND EVENING. INCREASING WARMTH AND HUMIDITY WILL
OVERSPREAD THE REGION THROUGH THE MID-WEEK IN THE WAKE OF THIS
FRONT. EXPECT WELL ABOVE NORMAL AFTERNOON TEMPERATURES ACROSS THE
WESTERN HALF OF THE STATE THIS AFTERNOON...AND IN ALL AREAS TUESDAY
AND WEDNESDAY. TEMPERATURES WILL COOL BACK BELOW NORMAL WITH DRIER
CONDITIONS BY THE WEEKEND AS A VERY COLD AIRMASS DROPS OUT OF
CENTRAL CANADA INTO THE GREAT LAKES AND NORTHEASTERN UNITED STATES.

&&

.NEAR TERM /UNTIL 10 PM THIS EVENING/...
EARLIER LOW STRATUS HAS TRANSITIONED INTO WIDESPREAD SCT-BKN FAIRLY
SHALLOW CU/STRATO CU FIELD ACROSS THE CWA AT MID AFTERNOON.

A RIBBON OF CONVECTION /NO THUNDER YET/ WAS DEVELOPING ACROSS THE
LAUREL WHERE EARLIER CLEARING AND HI LEVEL HEATING HAS RAMPED UP
MIXED LAYER CAPES TO AROUND 1500 J/KG. WARMING ALOFT SHOULD KEEP ANY
TSRA RATHER LOW-TOPPED AND ISOLATED LATE TODAY.

TEMPS ACROSS THE CENTRAL AND WEST ARE RIGHT AROUND THEIR FCST HIGHS
IN THE UPPER 70S TO LOWER 80S FOR HIGHS...AND SLIGHTLY COOLER IN THE
MID 70S ACROSS THE EAST. A FEW SPOTS IN SCENT PENN /JUST EAST OF THE
LAURELS/ COULD TOUCH 85F WHERE THE  MEAN...DOWNSLOPING SWRLY LLVL
FLOW MAXIMIZING THE ADIABATIC WARMING OF THE 14C AIR RESIDING AT THE
850 MB LEVEL.

ALTHOUGH ALL MDL SOUNDINGS CONTINUE TO INDICATE THE ISOLD/SCT SHRA
THAT ARE SEEN FORMING OVER THE PAST HOUR OR SO...IN THE SRN TIER AND
ANOTHER AREA OVER THE NWRN MTS...BROADLY DIVERGENT LLVL FLOW WILL
ACT TO NEGATE ANY ORGANIZED AREAS OF DEEP CONVECTION THROUGH THE
REST OF THE DAYLIGHT HOURS.

WILL INCREASE POPS TO HIGH CHC/ LOW LIKELY ACROSS THE SW MTNS ...BUT
CONTINUE TO KEEP POPS OVER THE NE HALF OF THE CWA BELOW 20 PERCENT.

&&

.SHORT TERM /10 PM THIS EVENING THROUGH 6 PM TUESDAY/...
MORE LOW STRATUS AND FOG ARE LIKELY LATE TONIGHT SINCE WILL
DEWPOINTS REMAIN HIGH AND WINDS WILL FALL OFF TO LIGHT AND VARIABLE.
WILL COUNT ON A FEW DEG C OF WARMING ALOFT AND LACK OF LLVL FORCING
IN THE WAKE OF THE SLOWLY NWD LIFTING WARM FRONT TO QUICKLY
DISSIPATE ANY LINGERING SHOWERS/STORMS THIS EVENING...AND LEAVE POPS
LESS THAN 20 PCT FOR THE BULK OF THE NIGHT. INCREASING CONVECTION
/OVER WRN LOWER MICHIGAN ATTM/ CRESTING THE UPPER RIDGE TO OUR WEST
COULD SNEAK INTO THE NW BY MORNING...BUT THIS IS JUST WORTH A LOW
CHC POP AT THIS POINT. MINS WILL AGAIN BE MUGGY UPPER 50S AND LOWER
60S.

TUESDAY...WE WILL BE BE WELL INTO THE WARM SECTOR AHEAD OF THE STORM
CRAWLING IN FROM THE NORTHERN PLAINS/MIDWEST/UPPER LAKES. THE WARM
SECTOR AIR WILL BE QUITE WARM FOR THIS TIME OF YEAR...HAVING SPENT
PLENTY OF TIME COOKING OVER THE MS AND OH VALLEYS WITH GOOD GULF
INFLOW. TEMPS THERE RIGHT NOW ARE ABOUT 10F ABOVE AVERAGES.
THEREFORE...SUMMERTIME TEMPS OF UPPER 70S IN THE HILLS TO MID 80S IN
THE VALLEYS ARE EXPECTED ON TUESDAY. ALONG WITH THE WARM
TEMPERATURES...THE DEWPOINTS WILL BE SOLIDLY IN THE 60S. THIS
WARM...MOIST AIR AND A WEAKENING RIDGE MOVING OVERHEAD AND A LITTLE
TO OUR EAST WILL CREATE A GOOD SITUATION FOR SCT AFTN CONVECTION.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
THE LARGE UPPER LEVEL LOW BRINGING SEVERE WEATHER THROUGHOUT THE
MIDWEST WILL SLOWLY MAKE ITS WAY EASTWARD. THIS FLOW SHOULD BRING A
RATHER UNSETTLED PERIOD THROUGH THE WORK WEEK. AS THE UPPER LEVEL
RIDGE CONTINUES TO BREAK DOWN...STORMS WILL SLOWLY APPROACH.  SEVERE
OUTLOOK FOR DAY3/WED HAS THE WESTERN HALF OF THE CWA IN THE SLIGHT
RISK. SOUTHEASTERLY MOISTURE...COUPLED WITH INSTABILITY FROM THE
FRONT AND DAYTIME HIGHS IN THE 80S SHOULD ALLOW FOR A SUFFICIENT
ENVIRONMENT FOR DAYTIME STORMS/SHOWERS. SHEAR SHOULD BE
DECENT...ESPECIALLY AS MID RANGE MODELS ARE HINTING AT A LLJ THROUGH
WEDNESDAY AFTERNOON. THURSDAY WILL AGAIN FEATURE SCT/NMRS TSRA. THE
MED RANGE GUID IS NOW PRETTY SOLID WITH A THURS NIGHT/EARLY FRIDAY
PASSAGE OF THE COLD FRONT ASSOCD WITH THE SYNOPTIC SCALE STORM. MUCH
COOLER AIR AND DRIER CONDITIONS SHOULD FOLLOW FOR THE WEEKEND. ECMWF
HAS BACKED OFF ON THE COLD-NESS OF THE AIR MOVING DOWN WITH THE BIG
1030MB HIGH FOR THE WEEKEND...THOUGH IT LOOKS LIKE THE ZERO C LINE
AT 8H COULD CLIP THE NORTHWESTERN CORNER OF PA. MIN TEMPS FOR
SATURDAY MORNING WILL BE COOL BUT HAVE KEPT THEM IN THE LOW 40S TO
UPPER 30S. DRIER AIR ASSOCIATED WITH THIS FRONT SHOULD KEEP
PRECIPITATION OUT OF THE FORECAST THROUGH THE WEEKEND...WITH WEAK
HIGH PRESSURE BUILDING THROUGH SUNDAY. MEMORIAL DAY MAY SEEM SOME
CLOUDINESS AS THE RIDGE BREAKS DOWN TO DUE NORTHWESTERLY FLOW.
MOISTURE FROM A WEAK SHORTWAVE COULD BRING PRECIPITATION ALONG THE
MASON DIXON MONDAY EVENING...YET DUE TO IT BEING ON THE EDGE OF THE
FORECAST MUCH COULD CHANGE.


&&

.AVIATION /19Z MONDAY THROUGH SATURDAY/...
A LIGHT SOUTH-SWRLY FLOW IN THE SFC-925 MB LAYER WILL OCCUR IN THE
WAKE OF A NWD DRIFTING WARM FRONT LATE TODAY AND TONIGHT.

HIGH DEWPOINTS AND LIGHT WINDS WILL LEAD TO THE REFORMATION OF LOW
STRATUS AND AREAS OF FOG /BLO 1SM/ AFTER 06Z TUESDAY. WIDESPREAD VFR
CONDITIONS THROUGH THIS EVENING WILL STEADILY DETERIORATE TO IFR
LATE...THEN RETURN TO MVFR AND VFR BETWEEN 13-16Z TUESDAY.

SCTD SHRA AND ISOLATED TSRA LATE TODAY AND TONIGHT WILL BE LIMITED
TO MAINLY THE WRN AND NRN MTNS.

.OUTLOOK...
TUE-THU...LOW CLOUDS/FOG POSS EARLY. SCT PM THUNDERSTORM IMPACTS
POSSIBLE.
FRI AND SAT...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT/DANGELO
LONG TERM...LA CORTE/CERU
AVIATION...LAMBERT

000
FXUS61 KCTP 201913
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
257 PM EDT MON MAY 20 2013

.SYNOPSIS...
A WARM FRONT WILL MOVE SLOWLY NORTHEAST ACROSS THE STATE THIS
AFTERNOON AND EVENING. INCREASING WARMTH AND HUMIDITY WILL
OVERSPREAD THE REGION THROUGH THE MID-WEEK IN THE WAKE OF THIS
FRONT. EXPECT WELL ABOVE NORMAL AFTERNOON TEMPERATURES ACROSS THE
WESTERN HALF OF THE STATE THIS AFTERNOON...AND IN ALL AREAS TUESDAY
AND WEDNESDAY. TEMPERATURES WILL COOL BACK BELOW NORMAL WITH DRIER
CONDITIONS BY THE WEEKEND AS A VERY COLD AIRMASS DROPS OUT OF
CENTRAL CANADA INTO THE GREAT LAKES AND NORTHEASTERN UNITED STATES.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
EARLIER LOW STRATUS HAS TRANSITIONED INTO WIDESPREAD SCT-BKN FAIRLY
SHALLOW CU/STRATO CU FIELD ACROSS THE CWA AT MID AFTERNOON.

A RIBBON OF CONVECTION /NO THUNDER YET/ WAS DEVELOPING ACROSS THE
LAUREL WHERE EARLIER CLEARING AND HI LEVEL HEATING HAS RAMPED UP
MIXED LAYER CAPES TO AROUND 1500 J/KG. WARMING ALOFT SHOULD KEEP ANY
TSRA RATHER LOW-TOPPED AND ISOLATED LATE TODAY.

TEMPS ACROSS THE CENTRAL AND WEST ARE RIGHT AROUND THEIR FCST HIGHS
IN THE UPPER 70S TO LOWER 80S FOR HIGHS...AND SLIGHTLY COOLER IN THE
MID 70S ACROSS THE EAST. A FEW SPOTS IN SCENT PENN /JUST EAST OF THE
LAURELS/ COULD TOUCH 85F WHERE THE  MEAN...DOWNSLOPING SWRLY LLVL
FLOW MAXIMIZING THE ADIABATIC WARMING OF THE 14C AIR RESIDING AT THE
850 MB LEVEL.

ALTHOUGH ALL MDL SOUNDINGS CONTINUE TO INDICATE THE ISOLD/SCT SHRA
THAT ARE SEEN FORMING OVER THE PAST HOUR OR SO...IN THE SRN TIER AND
ANOTHER AREA OVER THE NWRN MTS...BROADLY DIVERGENT LLVL FLOW WILL
ACT TO NEGATE ANY ORGANIZED AREAS OF DEEP CONVECTION THROUGH THE
REST OF THE DAYLIGHT HOURS.

WILL INCREASE POPS TO HIGH CHC/ LOW LIKELY ACROSS THE SW MTNS ...BUT
CONTINUE TO KEEP POPS OVER THE NE HALF OF THE CWA BELOW 20 PERCENT.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
MORE LOW STRATUS AND FOG ARE LIKELY LATE TONIGHT SINCE WILL
DEWPOINTS REMAIN HIGH AND WINDS WILL FALL OFF TO LIGHT AND VARIABLE.
WILL COUNT ON A FEW DEG C OF WARMING ALOFT AND LACK OF LLVL FORCING
IN THE WAKE OF THE SLOWLY NWD LIFTING WARM FRONT TO QUICKLY
DISSIPATE ANY LINGERING SHOWERS/STORMS THIS EVENING...AND LEAVE POPS
LESS THAN 20 PCT FOR THE BULK OF THE NIGHT. INCREASING CONVECTION
/OVER WRN LOWER MICHIGAN ATTM/ CRESTING THE UPPER RIDGE TO OUR WEST
COULD SNEAK INTO THE NW BY MORNING...BUT THIS IS JUST WORTH A LOW
CHC POP AT THIS POINT. MINS WILL AGAIN BE MUGGY UPPER 50S AND LOWER
60S.

TUESDAY...WE WILL BE BE WELL INTO THE WARM SECTOR AHEAD OF THE STORM
CRAWLING IN FROM THE NORTHERN PLAINS/MIDWEST/UPPER LAKES. THE WARM
SECTOR AIR WILL BE QUITE WARM FOR THIS TIME OF YEAR...HAVING SPENT
PLENTY OF TIME COOKING OVER THE MS AND OH VALLEYS WITH GOOD GULF
INFLOW. TEMPS THERE RIGHT NOW ARE ABOUT 10F ABOVE AVERAGES.
THEREFORE...SUMMERTIME TEMPS OF UPPER 70S IN THE HILLS TO MID 80S IN
THE VALLEYS ARE EXPECTED ON TUESDAY. ALONG WITH THE WARM
TEMPERATURES...THE DEWPOINTS WILL BE SOLIDLY IN THE 60S. THIS
WARM...MOIST AIR AND A WEAKENING RIDGE MOVING OVERHEAD AND A LITTLE
TO OUR EAST WILL CREATE A GOOD SITUATION FOR SCT AFTN CONVECTION.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
THE MEDIUM RANGE GUIDANCE CONTINUES TO ADVERTISE A RATHER UNSETTLED
PERIOD FOR MUCH OF THE UPCOMING WEEK.

WE ARE...AND WILL REMAIN BASICALLY UNDER A MEAN UPPER RIDGE...AND
THE STORM APPROACHING FROM THE WEST WILL TAKE IT/S TIME MOVING
THROUGH. SEVERE OUTLOOK FOR DAY3/WED DOES MENTION NWRN PA...CLOSE TO
THE SFC LOW AND THE BETTER UPPER FLOW. THURSDAY WILL AGAIN FEATURE
SCT/NMRS TSRA. THE MED RANGE GUID IS NOW PRETTY SOLID WITH A THURS
NIGHT/EARLY FRIDAY PASSAGE OF THE COLD FRONT ASSOCD WITH THE
SYNOPTIC SCALE STORM. MUCH COOLER AIR AND DRIER CONDITIONS SHOULD
FOLLOW FOR THE WEEKEND. ECMWF HAS BACKED OFF ON THE COLD-NESS OF THE
AIR MOVING DOWN WITH THE BIG 1030MB HIGH FOR THE WEEKEND...AND IS
MUCH CLOSER TO WHAT THE GFS HAS BEEN SAYING ABOUT THE AIRMASS. THE
ZERO C LINE AT 8H SEEMS TO STAY NORTH OF THE STATE NOW...WITH
MODIFICATION TAKING PLACE AS IT IS ALMOST SUMMER IN CANADA...TOO.

&&

.AVIATION /19Z MONDAY THROUGH SATURDAY/...
A LIGHT SOUTH-SWRLY FLOW IN THE SFC-925 MB LAYER WILL OCCUR IN THE
WAKE OF A NWD DRIFTING WARM FRONT LATE TODAY AND TONIGHT.

HIGH DEWPOINTS AND LIGHT WINDS WILL LEAD TO THE REFORMATION OF LOW
STRATUS AND AREAS OF FOG /BLO 1SM/ AFTER 06Z TUESDAY. WIDESPREAD VFR
CONDITIONS THROUGH THIS EVENING WILL STEADILY DETERIORATE TO IFR
LATE...THEN RETURN TO MVFR AND VFR BETWEEN 13-16Z TUESDAY.

SCTD SHRA AND ISOLATED TSRA LATE TODAY AND TONIGHT WILL BE LIMITED
TO MAINLY THE WRN AND NRN MTNS.

.OUTLOOK...
TUE-THU...LOW CLOUDS/FOG POSS EARLY. SCT PM THUNDERSTORM IMPACTS
POSSIBLE.
FRI AND SAT...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT/DANGELO
LONG TERM...LA CORTE/CERU
AVIATION...LAMBERT

000
FXUS61 KCTP 201851
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
251 PM EDT MON MAY 20 2013

.SYNOPSIS...
A WARM FRONT WILL MOVE SLOWLY NORTHEAST ACROSS THE STATE THIS
AFTERNOON AND EVENING. INCREASING WARMTH AND HUMIDITY WILL
OVERSPREAD THE REGION THROUGH THE MID-WEEK IN THE WAKE OF THIS
FRONT. EXPECT WELL ABOVE NORMAL AFTERNOON TEMPERATURES ACROSS THE
WESTERN HALF OF THE STATE THIS AFTERNOON...AND IN ALL AREAS TUESDAY
AND WEDNESDAY. TEMPERATURES WILL COOL BACK BELOW NORMAL WITH DRIER
CONDITIONS BY THE WEEKEND AS A VERY COLD AIRMASS DROPS OUT OF
CENTRAL CANADA INTO THE GREAT LAKES AND NORTHEASTERN UNITED STATES.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MOISTURE AND THE ASSOCIATED EARLIER...EXTENSIVE DECK OF LOW
STRATUS/FOG WAS STILL TRAPPED UNDER THE STEEP INVERSION ACROSS THE
EASTERN HALF OF THE CWA. OVER APPROXIMATELY THE WRN HALF OF THE
STATE...THE CLOUD BASES HAVE BROKEN/LIFTED BY 1-2 KFT TO A
BKN...SHALLOW CU FIELD AS OF 16Z.

THE CLOUDS WILL BE SLOWLY MIXED OUT/DISSIPATED FROM WEST TO EAST
ACROSS THE SUSQ VALLEY DURING THE AFTERNOON HOURS. HOWEVER...A FEW
LOCATIONS EAST OF THE SUSQ VALLEY WILL STILL REMAIN CLOUDY FOR THE
REST OF THE DAY WITH TEMPS ONLY PEAKING IN THE MID 70S.

HIGH TEMPS ACROSS THE CENTRAL AND WEST WILL EASILY REACH THE UPPER
70S TO LOWER 80S FOR HIGHS UNDER A DECENT AMOUNT OF HAZY SUNSHINE.
A FEW SPOTS IN SCENT PENN /JUST EAST OF THE LAURELS/ COULD TOUCH 85F
WHERE THE MEAN...DOWNSLOPING SWRLY LLVL FLOW MAXIMIZING THE
ADIABATIC WARMING OF THE 14C AIR RESIDING AT THE 850 MB LEVEL.

ALTHOUGH ALL MDL SOUNDINGS BREAK THE INVERSION AND SUGGEST ISOLD/SCT
SHRA FORMING IN THE SRN TIER AND ANOTHER AREA OVER THE NWRN
MTS...BROADLY DIVERGENT LLVL FLOW WILL ACT TO NEGATE ANY ORGANIZED
AREAS OF CONVECTION THROUGH THE DAYLIGHT HOURS /FOR ALL AREAS EXCEPT
FOR PERHAPS WARREN CTY WHERE TSRA DEVELOPING ON THE WESTERN EDGE OF
A TIGHT 925-850 MB THETA-E BOUNDARY /JUST WEST OF KCLE/ COULD DRIFT
EAST AND AFFECT THE FAR NW ZONES AROUND DUSK.

WILL CONTINUE TO KEEP POPS LOWEST IN THE NE AND CENTRAL MTS...AOB 20
PERCENT.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
MORE STRATUS AND FOG ARE POSSIBLE TONIGHT SINCE DEWPOINTS REMAIN
HIGH AND WINDS WILL STILL BE LIGHT. WILL COUNT ON THE LACK OF SUN
TO KILL THE SHOWERS/STORMS THIS EVENING...AND LEAVE POPS LESS THAN
20 PCT FOR THE BULK OF THE NIGHT. CONVECTION CRESTING THE UPPER
RIDGE TO OUR WEST COULD SNEAK INTO THE NW BY MORNING...BUT THIS IS
JUST WORTH A LOW CHC POP AT THIS POINT. MINS WILL AGAIN BE MUGGY
UPPER 50S AND LOWER 60S.

ON TUESDAY...WE SHOULD BE WELL INTO THE WARM SECTOR AHEAD OF THE
STORM CRAWLING IN FROM THE NORTHERN PLAINS/MIDWEST/UPPER LAKES.
THE WARM SECTOR AIR WILL BE QUITE WARM FOR THIS TIME OF
YEAR...HAVING SPENT PLENTY OF TIME COOKING OVER THE MS AND OH
VALLEYS WITH GOOD GULF INFLOW. TEMPS THERE RIGHT NOW ARE ABOUT 10F
ABOVE AVERAGES. THEREFORE...SUMMERTIME TEMPS OF UPPER 70S IN THE
HILLS TO MID 80S IN THE VALLEYS ARE EXPECTED ON TUESDAY. ALONG
WITH THE WARM TEMPERATURES...THE DEWPOINTS WILL BE SOLIDLY IN THE
60S. THIS WARM...MOIST AIR AND A WEAKENING RIDGE MOVING OVERHEAD
AND A LITTLE TO OUR EAST WILL CREATE A GOOD SITUATION FOR SCT AFTN
CONVECTION.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...

THE LARGE UPPER LEVEL LOW BRINGING SEVERE WEATHER THROUGHOUT THE
MIDWEST WILL SLOWLY MAKE ITS WAY EASTWARD. THIS FLOW SHOULD BRING A
RATHER UNSETTLED PERIOD THROUGH THE WORK WEEK. AS THE UPPER LEVEL
RIDGE CONTINUES TO BREAK DOWN...STORMS WILL SLOWLY APPROACH.
 SEVERE OUTLOOK FOR DAY3/WED HAS THE WESTERN HALF OF THE CWA IN THE
SLIGHT RISK. SOUTHEASTERLY MOISTURE...COUPLED WITH INSTABILITY FROM
THE FRONT AND DAYTIME HIGHS IN THE 80S SHOULD ALLOW FOR A SUFFICIENT
ENVIRONMENT FOR DAYTIME STORMS/SHOWERS. SHEAR SHOULD BE
DECENT...ESPECIALLY AS MID RANGE MODELS ARE HINTING AT A LLJ THROUGH
WEDNESDAY AFTERNOON. THURSDAY WILL AGAIN FEATURE SCT/NMRS TSRA. THE
MED RANGE GUID IS NOW PRETTY SOLID WITH A THURS NIGHT/EARLY FRIDAY
PASSAGE OF THE COLD FRONT ASSOCD WITH THE SYNOPTIC SCALE STORM. MUCH
COOLER AIR AND DRIER CONDITIONS SHOULD FOLLOW FOR THE WEEKEND. ECMWF
HAS BACKED OFF ON THE COLD-NESS OF THE AIR MOVING DOWN WITH THE BIG
1030MB HIGH FOR THE WEEKEND...THOUGH IT LOOKS LIKE THE ZERO C LINE
AT 8H COULD CLIP THE NORTHWESTERN CORNER OF PA. MIN TEMPS FOR
SATURDAY MORNING WILL BE COOL BUT HAVE KEPT THEM IN THE LOW 40S TO
UPPER 30S. DRIER AIR ASSOCIATED WITH THIS FRONT SHOULD KEEP
PRECIPITATION OUT OF THE FORECAST THROUGH THE WEEKEND...WITH WEAK
HIGH PRESSURE BUILDING THROUGH SUNDAY. MEMORIAL DAY MAY SEEM SOME
CLOUDINESS AS THE RIDGE BREAKS DOWN TO DUE NORTHWESTERLY FLOW.
MOISTURE FROM A WEAK SHORTWAVE COULD BRING PRECIPITATION ALONG THE
MASON DIXON MONDAY EVENING...YET DUE TO IT BEING ON THE EDGE OF THE
FORECAST MUCH COULD CHANGE.


&&

.AVIATION /19Z MONDAY THROUGH SATURDAY/...
A MOIST SERLY FLOW OFF OF THE ATLANTIC OCEAN /AND ON THE NE SIDE OF
A SLOW MOVING WARM FRONT/ WILL CONTINUE TO PRODUCE WIDESPREAD
STRATUS WITH MAINLY MVFR CIGS ACROSS THE EASTERN HALF OF PA THIS
AFTERNOON. GENERALLY BKN CIGS WITH BASES OF 3.4-4.5 KFT AGL WILL
OCCUR ACROSS THE REGION NEAR...AND TO THE WEST OF A KELM...TO KUNV
AND KMRB LINE FOR THE REST OF TODAY.

THERE IS A SLIGHT CHC OF AN AFTN TSRA ACROSS THE W MTNS...WHICH
COULD PRODUCE A BRIEF VIS/CIG REDUCTION.

.OUTLOOK...
TUE-THU...LOW CLOUDS/FOG POSS EARLY. SCT PM THUNDERSTORM IMPACTS
POSSIBLE.
FRI AND SAT...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...LA CORTE/LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...DANGELO/LAMBERT
LONG TERM...LA CORTE/CERU
AVIATION...LAMBERT/GARTNER

000
FXUS61 KCTP 201637
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1216 PM EDT MON MAY 20 2013

.SYNOPSIS...
A WARM FRONT WILL MOVE SLOWLY NORTHEAST ACROSS THE STATE THIS
AFTERNOON AND EVENING. INCREASING WARMTH AND HUMIDITY WILL
OVERSPREAD THE REGION THROUGH THE MID-WEEK IN THE WAKE OF THIS
FRONT. EXPECT WELL ABOVE NORMAL AFTERNOON TEMPERATURES ACROSS THE
WESTERN HALF OF THE STATE THIS AFTERNOON...AND IN ALL AREAS TUESDAY
AND WEDNESDAY. TEMPERATURES WILL COOL BACK BELOW NORMAL WITH DRIER
CONDITIONS BY THE WEEKEND AS A VERY COLD AIRMASS DROPS OUT OF
CENTRAL CANADA INTO THE GREAT LAKES AND NORTHEASTERN UNITED STATES.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MOISTURE AND THE ASSOCIATED EARLIER...EXTENSIVE DECK OF LOW
STRATUS/FOG WAS STILL TRAPPED UNDER THE STEEP INVERSION ACROSS THE
EASTERN HALF OF THE CWA. OVER APPROXIMATELY THE WRN HALF OF THE
STATE...THE CLOUD BASES HAVE BROKEN/LIFTED BY 1-2 KFT TO A
BKN...SHALLOW CU FIELD AS OF 16Z.

THE CLOUDS WILL BE SLOWLY MIXED OUT/DISSIPATED FROM WEST TO EAST
ACROSS THE SUSQ VALLEY DURING THE AFTERNOON HOURS. HOWEVER...A FEW
LOCATIONS EAST OF THE SUSQ VALLEY WILL STILL REMAIN CLOUDY FOR THE
REST OF THE DAY WITH TEMPS ONLY PEAKING IN THE MID 70S.

HIGH TEMPS ACROSS THE CENTRAL AND WEST WILL EASILY REACH THE UPPER
70S TO LOWER 80S FOR HIGHS UNDER A DECENT AMOUNT OF HAZY SUNSHINE.
A FEW SPOTS IN SCENT PENN /JUST EAST OF THE LAURELS/ COULD TOUCH 85F
WHERE THE MEAN...DOWNSLOPING SWRLY LLVL FLOW MAXIMIZING THE
ADIABATIC WARMING OF THE 14C AIR RESIDING AT THE 850 MB LEVEL.

ALTHOUGH ALL MDL SOUNDINGS BREAK THE INVERSION AND SUGGEST ISOLD/SCT
SHRA FORMING IN THE SRN TIER AND ANOTHER AREA OVER THE NWRN
MTS...BROADLY DIVERGENT LLVL FLOW WILL ACT TO NEGATE ANY ORGANIZED
AREAS OF CONVECTION THROUGH THE DAYLIGHT HOURS /FOR ALL AREAS EXCEPT
FOR PERHAPS WARREN CTY WHERE TSRA DEVELOPING ON THE WESTERN EDGE OF
A TIGHT 925-850 MB THETA-E BOUNDARY /JUST WEST OF KCLE/ COULD DRIFT
EAST AND AFFECT THE FAR NW ZONES AROUND DUSK.

WILL CONTINUE TO KEEP POPS LOWEST IN THE NE AND CENTRAL MTS...AOB 20
PERCENT.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
MORE STRATUS AND FOG ARE POSSIBLE TONIGHT SINCE DEWPOINTS REMAIN
HIGH AND WINDS WILL STILL BE LIGHT. WILL COUNT ON THE LACK OF SUN
TO KILL THE SHOWERS/STORMS THIS EVENING...AND LEAVE POPS LESS THAN
20 PCT FOR THE BULK OF THE NIGHT. CONVECTION CRESTING THE UPPER
RIDGE TO OUR WEST COULD SNEAK INTO THE NW BY MORNING...BUT THIS IS
JUST WORTH A LOW CHC POP AT THIS POINT. MINS WILL AGAIN BE MUGGY
UPPER 50S AND LOWER 60S.

ON TUESDAY...WE SHOULD BE WELL INTO THE WARM SECTOR AHEAD OF THE
STORM CRAWLING IN FROM THE NORTHERN PLAINS/MIDWEST/UPPER LAKES.
THE WARM SECTOR AIR WILL BE QUITE WARM FOR THIS TIME OF
YEAR...HAVING SPENT PLENTY OF TIME COOKING OVER THE MS AND OH
VALLEYS WITH GOOD GULF INFLOW. TEMPS THERE RIGHT NOW ARE ABOUT 10F
ABOVE AVERAGES. THEREFORE...SUMMERTIME TEMPS OF UPPER 70S IN THE
HILLS TO MID 80S IN THE VALLEYS ARE EXPECTED ON TUESDAY. ALONG
WITH THE WARM TEMPERATURES...THE DEWPOINTS WILL BE SOLIDLY IN THE
60S. THIS WARM...MOIST AIR AND A WEAKENING RIDGE MOVING OVERHEAD
AND A LITTLE TO OUR EAST WILL CREATE A GOOD SITUATION FOR SCT AFTN
CONVECTION.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
THE MEDIUM RANGE GUIDANCE CONTINUES TO ADVERTISE A RATHER UNSETTLED
PERIOD FOR MUCH OF THE UPCOMING WEEK.

WE ARE AND WILL REMAIN BASICALLY UNDER A MEAN UPPER RIDGE...AND
THE STORM APPROACHING FROM THE WEST WILL TAKE IT/S TIME MOVING
THROUGH. SEVERE OUTLOOK FOR DAY3/WED DOES MENTION NWRN PA...CLOSE
TO THE SFC LOW AND THE BETTER UPPER FLOW. THURSDAY WILL AGAIN
FEATURE SCT/NMRS TSRA. THE MED RANGE GUID IS NOW PRETTY SOLID WITH
A THURS NIGHT/EARLY FRIDAY PASSAGE OF THE COLD FRONT ASSOCD WITH
THE SYNOPTIC SCALE STORM. MUCH COOLER AIR AND DRIER CONDITIONS
SHOULD FOLLOW FOR THE WEEKEND. ECMWF HAS BACKED OFF ON THE
COLD-NESS OF THE AIR MOVING DOWN WITH THE BIG 1030MB HIGH FOR THE
WEEKEND...AND IS MUCH CLOSER TO WHAT THE GFS HAS BEEN SAYING ABOUT
THE AIRMASS. THE ZERO C LINE AT 8H SEEMS TO STAY NORTH OF THE STATE
NOW...WITH MODIFICATION TAKING PLACE AS IT IS ALMOST SUMMER IN
CANADA...TOO.

&&

.AVIATION /16Z MONDAY THROUGH FRIDAY/...
A MOIST SERLY FLOW OFF OF THE ATLANTIC OCEAN /AND ON THE NE SIDE OF
A SLOW MOVING WARM FRONT/ WILL CONTINUE TO PRODUCE WIDESPREAD
STRATUS WITH MAINLY MVFR CIGS ACROSS THE EASTERN HALF OF PA THIS
AFTERNOON. GENERALLY BKN CIGS WITH BASES OF 3.4-4.5 KFT AGL WILL
OCCUR ACROSS THE REGION NEAR...AND TO THE WEST OF A KELM...TO KUNV
AND KMRB LINE FOR THE REST OF TODAY.

THERE IS A SLIGHT CHC OF AN AFTN TSRA ACROSS THE W MTNS...WHICH
COULD PRODUCE A BRIEF VIS/CIG REDUCTION.

.OUTLOOK...
TUE-THU...LOW CLOUDS/FOG POSS EARLY. SCT PM THUNDERSTORM IMPACTS
POSSIBLE.
FRI AND SAT...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...LA CORTE/LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...DANGELO
LONG TERM...LA CORTE/CERU
AVIATION...LAMBERT/GARTNER

000
FXUS61 KCTP 201322
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
912 AM EDT MON MAY 20 2013

.SYNOPSIS...
A WARM FRONT WILL ATTEMPT TO MOVE THROUGH THE AREA TODAY. IT SHOULD
SUCCEED IN DOING SO...BRINGING INCREASING WARMTH AND HUMIDITY TO
THE REGION THROUGH MID-WEEK. EXPECT WELL ABOVE NORMAL AFTERNOON
TEMPERATURES TUESDAY AND WEDNESDAY. TEMPERATURES WILL COOL BACK
BELOW NORMAL WITH DRIER CONDITIONS BY THE WEEKEND AS A VERY COLD
AIRMASS DROPS OUT OF CENTRAL CANADA INTO THE GREAT LAKES AND
NORTHEASTERN UNITED STATES.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MOISTURE AND ASSOCIATED EXTENSIVE LOW STRATUS/FOG...STILL TRAPPED
UNDER THE STEEP INVERSION WILL GRADUALLY BE MIXED OUT/DISSIPATED
FROM WEST TO EAST DURING THE DAY TODAY THANKS TO A MEAN SFC-850 MB
FLOW FROM THE SSW.

THE STRATUS WILL BE MOST STUBBORN TO BREAK UP ACROSS THE EASTERN
HALF OF THE CWA...WHERE SOME AREAS MAY NOT GET RID OF THE CLOUDS BY
THE END OF THE DAY. THE FRONT IS STILL VERY DIFFICULT TO MAKE OUT
DUE TO RATHER SIMILAR DEWPOINTS AND RATHER GENTLE GRADIENT TO THE
SFC PRESSURE. THE RIDGE AXIS IS WELL OFF SHORE NOW BUT THE LACK OF
GOOD SRLY WIND IS A TICK MARK ON THE NEGATIVE SIDE FOR THE FRONT TO
MAKE IT THROUGH THE AREA TODAY. ON THE PLUS SIDE IF THE LEDGER SHEET
- THE STRONG MAY SUNSHINE - WE ARE NOW ONLY 1 MONTH FROM SOLSTICE -
SHOULD WORK ON THE EDGES OF THE STRATUS AND PERCOLATE SOME DIURNAL
CU. ALL MDL SOUNDINGS BREAK THE INVERSION AND CREATE ISOLD/SCT SHRA
IN THE SRN TIER AND ANOTHER AREA OVER THE NWRN MTS. WILL KEEP POPS
LOWEST IN THE NE AND CENTRAL MTS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
MORE STRATUS AND FOG ARE POSSIBLE TONIGHT SINCE DEWPOINTS REMAIN
HIGH AND WINDS WILL STILL BE LIGHT. WILL COUNT ON THE LACK OF SUN
TO KILL THE SHOWERS/STORMS THIS EVENING...AND LEAVE POPS LESS THAN
20 PCT FOR THE BULK OF THE NIGHT. CONVECTION CRESTING THE UPPER
RIDGE TO OUR WEST COULD SNEAK INTO THE NW BY MORNING...BUT THIS IS
JUST WORTH A LOW CHC POP AT THIS POINT. MINS WILL AGAIN BE MUGGY
UPPER 50S AND LOWER 60S.

ON TUESDAY...WE SHOULD BE WELL INTO THE WARM SECTOR AHEAD OF THE
STORM CRAWLING IN FROM THE NORTHERN PLAINS/MIDWEST/UPPER LAKES.
THE WARM SECTOR AIR WILL BE QUITE WARM FOR THIS TIME OF
YEAR...HAVING SPENT PLENTY OF TIME COOKING OVER THE MS AND OH
VALLEYS WITH GOOD GULF INFLOW. TEMPS THERE RIGHT NOW ARE ABOUT 10F
ABOVE AVERAGES. THEREFORE...SUMMERTIME TEMPS OF UPPER 70S IN THE
HILLS TO MID 80S IN THE VALLEYS ARE EXPECTED ON TUESDAY. ALONG
WITH THE WARM TEMPERATURES...THE DEWPOINTS WILL BE SOLIDLY IN THE
60S. THIS WARM...MOIST AIR AND A WEAKENING RIDGE MOVING OVERHEAD
AND A LITTLE TO OUR EAST WILL CREATE A GOOD SITUATION FOR SCT AFTN
CONVECTION.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
THE MEDIUM RANGE GUIDANCE CONTINUES TO ADVERTISE A RATHER UNSETTLED
PERIOD FOR MUCH OF THE UPCOMING WEEK.

WE ARE AND WILL REMAIN BASICALLY UNDER A MEAN UPPER RIDGE...AND
THE STORM APPROACHING FROM THE WEST WILL TAKE IT/S TIME MOVING
THROUGH. SEVERE OUTLOOK FOR DAY3/WED DOES MENTION NWRN PA...CLOSE
TO THE SFC LOW AND THE BETTER UPPER FLOW. THURSDAY WILL AGAIN
FEATURE SCT/NMRS TSRA. THE MED RANGE GUID IS NOW PRETTY SOLID WITH
A THURS NIGHT/EARLY FRIDAY PASSAGE OF THE COLD FRONT ASSOCD WITH
THE SYNOPTIC SCALE STORM. MUCH COOLER AIR AND DRIER CONDITIONS
SHOULD FOLLOW FOR THE WEEKEND. ECMWF HAS BACKED OFF ON THE
COLD-NESS OF THE AIR MOVING DOWN WITH THE BIG 1030MB HIGH FOR THE
WEEKEND...AND IS MUCH CLOSER TO WHAT THE GFS HAS BEEN SAYING ABOUT
THE AIRMASS. THE ZERO C LINE AT 8H SEEMS TO STAY NORTH OF THE STATE
NOW...WITH MODIFICATION TAKING PLACE AS IT IS ALMOST SUMMER IN
CANADA...TOO.

&&

.AVIATION /13Z MONDAY THROUGH FRIDAY/...
A MOIST SERLY FLOW OFF OF THE ATLANTIC OCEAN WILL CONTINUE TO
PRODUCE WIDESPREAD STRATUS IFR-MVFR CIGS ACROSS CENTRAL PA THIS
MORNING WITH CIGS SLOWLY IMPROVING TO ABOVE 1000 FT AT MOST
AIRFIELDS BY 16Z. A BIT OF DRIZZLE AND AREAS OF FOG WILL ALSO ADD TO
LOWER VSBYS AT CIGS BLO 1000 FT AGL THROUGH THE REST OF THIS MORNING
ACROSS NRN AND EASTERN PARTS OF THE STATE...THAT WILL STAY LOCATED
JUST TO THE NORTH OF A QUASI STATIONARY SFC FRONT /EXTENDING FROM
NEAR KYNG TO KAOO AND KTHV AT 13Z/.

THIS BOUNDARY WILL LIFT GRADUALLY NORTH AS A WARM FRONT TODAY AS
THE MEAN SFC-850 MB FLOW SHIFTS TO THE SSW. MDL SOUNDINGS AND SREF
DATA INDICATE PREDOMINATELY VFR CONDS ARE LIKELY EVERYWHERE BY THE
AFTN. HOWEVER...THERE IS A SLIGHT CHC OF AN AFTN TSRA ACROSS THE W
MTNS...WHICH COULD PRODUCE A BRIEF VIS/CIG REDUCTION.

.OUTLOOK...
TUE-THU...LOW CLOUDS/FOG POSS EARLY. SCT PM THUNDERSTORM IMPACTS
POSSIBLE. FRI...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...LA CORTE/LAMBERT
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...DANGELO
LONG TERM...LA CORTE/CERU
AVIATION...LAMBERT/GARTNER

000
FXUS61 KCTP 200923
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
523 AM EDT MON MAY 20 2013

.SYNOPSIS...
A WARM FRONT WILL ATTEMPT TO MOVE THROUGH THE AREA TODAY. IT SHOULD
SUCCEED IN DOING SO...BRINGING INCREASING WARMTH AND HUMIDITY TO
THE REGION THROUGH MID-WEEK. EXPECT WELL ABOVE NORMAL AFTERNOON
TEMPERATURES TUESDAY AND WEDNESDAY. TEMPERATURES WILL COOL BACK
BELOW NORMAL WITH DRIER CONDITIONS BY THE WEEKEND AS A VERY COLD
AIRMASS DROPS OUT OF CENTRAL CANADA INTO THE GREAT LAKES AND
NORTHEASTERN UNITED STATES.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MOISTURE STILL TRAPPED UNDER THE STEEP INVERSION AND STRATUS IS
EVEN TRYING TO RE-ESTABLISH OVER WRN PA AT 09Z. THE STRATUS WILL
BE STUBBORN TO BREAK UP AND SOME EASTERN AREAS MAY NOT GET RID OF
THE CLOUDS BY THE END OF THE DAY. THE FRONT IS STILL VERY
DIFFICULT TO MAKE OUT DUE TO RATHER SIMILAR DEWPOINTS AND RATHER
GENTLE GRADIENT TO THE SFC PRESSURE. THE RIDGE AXIS IS WELL OFF
SHORE NOW BUT THE LACK OF GOOD SRLY WIND IS A TICK MARK ON THE
NEGATIVE SIDE FOR THE FRONT TO MAKE IT THROUGH THE AREA TODAY. ON
THE PLUS SIDE IF THE LEDGER SHEET - THE STRONG MAY SUNSHINE - WE
ARE NOW ONLY 1 MONTH FROM SOLSTICE - SHOULD WORK ON THE EDGES OF
THE STRATUS AND PERCOLATE SOME DIURNAL CU. ALL MDL SOUNDINGS BREAK
THE INVERSION AND CREATE ISOLD/SCT SHRA IN THE SRN TIER AND
ANOTHER AREA OVER THE NWRN MTS. WILL KEEP POPS LOWEST IN THE NE
AND CENTRAL MTS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
MORE STRATUS AND FOG ARE POSSIBLE TONIGHT SINCE DEWPOINTS REMAIN
HIGH AND WINDS WILL STILL BE LIGHT. WILL COUNT ON THE LACK OF SUN
TO KILL THE SHOWERS/STORMS THIS EVENING...AND LEAVE POPS LESS THAN
20 PCT FOR THE BULK OF THE NIGHT. CONVECTION CRESTING THE UPPER
RIDGE TO OUR WEST COULD SNEAK INTO THE NW BY MORNING...BUT THIS IS
JUST WORTH A LOW CHC POP AT THIS POINT. MINS WILL AGAIN BE MUGGY
UPPER 50S AND LOWER 60S.

ON TUESDAY...WE SHOULD BE WELL INTO THE WARM SECTOR AHEAD OF THE
STORM CRAWLING IN FROM THE NORTHERN PLAINS/MIDWEST/UPPER LAKES.
THE WARM SECTOR AIR WILL BE QUITE WARM FOR THIS TIME OF
YEAR...HAVING SPENT PLENTY OF TIME COOKING OVER THE MS AND OH
VALLEYS WITH GOOD GULF INFLOW. TEMPS THERE RIGHT NOW ARE ABOUT 10F
ABOVE AVERAGES. THEREFORE...SUMMERTIME TEMPS OF UPPER 70S IN THE
HILLS TO MID 80S IN THE VALLEYS ARE EXPECTED ON TUESDAY. ALONG
WITH THE WARM TEMPERATURES...THE DEWPOINTS WILL BE SOLIDLY IN THE
60S. THIS WARM...MOIST AIR AND A WEAKENING RIDGE MOVING OVERHEAD
AND A LITTLE TO OUR EAST WILL CREATE A GOOD SITUATION FOR SCT AFTN
CONVECTION.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
THE MEDIUM RANGE GUIDANCE CONTINUES TO ADVERTISE A RATHER UNSETTLED
PERIOD FOR MUCH OF THE UPCOMING WEEK.

WE ARE AND WILL REMAIN BASICALLY UNDER A MEAN UPPER RIDGE...AND
THE STORM APPROACHING FROM THE WEST WILL TAKE IT/S TIME MOVING
THROUGH. SEVERE OUTLOOK FOR DAY3/WED DOES MENTION NWRN PA...CLOSE
TO THE SFC LOW AND THE BETTER UPPER FLOW. THURSDAY WILL AGAIN
FEATURE SCT/NMRS TSRA. THE MED RANGE GUID IS NOW PRETTY SOLID WITH
A THURS NIGHT/EARLY FRIDAY PASSAGE OF THE COLD FRONT ASSOCD WITH
THE SYNOPTIC SCALE STORM. MUCH COOLER AIR AND DRIER CONDITIONS
SHOULD FOLLOW FOR THE WEEKEND. ECMWF HAS BACKED OFF ON THE COLD-
NESS OF THE AIR MOVING DOWN WITH THE BIG 1030MB HIGH FOR THE
WEEKEND...AND IS MUCH CLOSER TO WHAT THE GFS HAS BEEN SAYING ABOUT
THE AIRMASS. THE ZERO C LINE AT 8H SEEMS TO STAY NORTH OF THE
STATE NOW...WITH MODIFICATION TAKING PLACE AS IT IS ALMOST SUMMER
IN CANADA...TOO.

&&

.AVIATION /09Z MONDAY THROUGH FRIDAY/...
A MOIST SERLY FLOW OFF OF THE ATLANTIC OCEAN WILL CONTINUE TO
PRODUCE WIDESPREAD STRATUS AND LIFR/IFR CIGS ACROSS CENTRAL PA
OVERNIGHT WITH CIGS BLO 1000 FT AT MOST AIRFIELDS. A BIT OF
DRIZZLE AND AREAS OF FOG WILL ALSO ADD TO LOWER VSBYS AT MANY SITES.
NEAR TERM MDL DATA INDICATING A NEARLY SATURATED SFC- 900MB LYR
ACROSS THE AREA TONIGHT.

SIGNIFICANT IMPROVEMENT IN FLYING CONDS IS EXPECTED LATER THIS
MORNING/AFTER SUNRISE...AS A WARM FRONT LIFTS THRU THE AREA AND
SFC FLOW SHIFTS TO THE SSW. MDL SOUNDINGS AND SREF DATA INDICATE
PREDOMINATELY VFR CONDS ARE LIKELY EVERYWHERE BY THE AFTN.
HOWEVER...THERE IS A SLIGHT CHC OF AN AFTN TSRA ACROSS THE W
MTNS...WHICH COULD PRODUCE A BRIEF VIS/CIG REDUCTION.

.OUTLOOK...
TUE-THU...LOW CLOUDS/FOG POSS EARLY. SCT PM THUNDERSTORM IMPACTS
POSSIBLE. FRI...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...LA CORTE/LAMBERT
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...LA CORTE/CERU
AVIATION...FITZGERALD/GARTNER

000
FXUS61 KCTP 200740
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
340 AM EDT MON MAY 20 2013

.SYNOPSIS...
HIGH PRESSURE OFF THE NEW ENGLAND COAST WILL MAINTAIN A MOIST
SOUTHEASTERLY FLOW OVER THE REGION OVERNIGHT. A WARM FRONT WILL
ATTEMPT TO MOVE THROUGH THE FORECAST LATER TODAY. IT SHOULD
SUCCEED IN DOING SO...BRINGING INCREASING WARMTH AND HUMIDITY TO
THE REGION THROUGH MID-WEEK. EXPECT WELL ABOVE NORMAL AFTERNOON
TEMPERATURES TUESDAY AND WEDNESDAY. TEMPERATURES WILL COOL BACK
BELOW NORMAL WITH DRIER CONDITIONS BY THE WEEKEND.

&&

.NEAR TERM /UNTIL 8 AM THIS MORNING/...
THE PREPONDERANCE OF PARAMETERS PROCEED PER PRE-ESTABLISHED
PROGNOSTICATIONS. PREVIOUS FORECASTS SHALL PREVAIL.

THE REGION REMAINS STRONGLY COOL AIR DAMMED...WITH WIDESPREAD LOW
CLOUDS AND AREAS OF DRIZZLE AND VERY LIGHT RAIN. THIS WILL
CONTINUE OVERNIGHT. THE BLANKET OF CLOUDS AND RELATIVELY HIGH SFC
DEWPOINTS...IN MID 50S TO AROUND 60F WILL KEEP TEMPS 10-15F ABOVE
NORMAL OVERNIGHT.

&&

.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM TUESDAY/...
UPPER RIDGE WILL BE IN PLACE FROM THE OHIO VALLEY TO THE GULF COAST.
500 MB HEIGHTS WILL RISE SLIGHTLY /BY 10-20M/ DURING THE DAY
MONDAY...AS THE MEAN /AND INITIALLY SOUTHERLY/ 925-850 MB FLOW VEERS
AROUND TO THE WSW BY THE MIDDAY HOURS MONDAY.

LINGERING...EARLY MORNING LOW CLOUDS AND FOG SHOULD BE ERODED RATHER
QUICKLY BETWEEN 14-17Z MONDAY...WITH PARTLY SUNNY SKIES IN MOST
AREAS FOR THE AFTERNOON HOURS. DEEP VERTICAL MIXING OF THE WARM
/PLUS 14-15C/ AIR AT 850 MB WILL YIELD ABOVE NORMAL AFTERNOON TEMPS
IN THE MID 70S TO AROUND 80F.

SOME OF THE DEEPER VALLEYS EAST OF THE LAUREL HIGHLANDS...WHERE THE
GREATEST COMPRESSIONAL WARMING WILL OCCUR VIA AN ORTHOGONAL LLVL WSW
FLOW...COULD SOAR INTO THE LOWERS 80S IF AMPLE CLEARING OCCURS AND
SCTD SHOWERS/TSRA HOLD OFF UNTIL AFTER 20Z.

POPS FOR SCTD SHOWERS AND ISOLATED TSRA FOR MONDAY AFTERNOON WILL BE
JUST UNDER 30 PERCENT ACROSS THE NW ZONES...AND 40-45 PERCENT IN THE
SE.

WEAK LOW PRESSURE ALOFT WILL FINALLY DISAPPEAR MONDAY NIGHT AS IT
PASSES OVERHEAD. UPSTREAM CONVECTION WILL BE DROPPING ACROSS THE
GREAT LAKES AND WILL ONLY PROLONG THE CLOUDY/SHOWERY FORECAST FOR
LATE THIS PERIOD.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
ON TUESDAY...WE SHOULD ENTER THE WARM SECTOR AHEAD OF THE STORM
LANGUISHING OVER THE PLAINS/MIDWEST/UPPER LAKES. THE WARM SECTOR
AIR WILL BE QUITE WARM FOR THE TIME OF YEAR...HAVING SPENT PLENTY
OF TIME COOKING OVER THE MS AND OH VALLEYS WITH GOOD GULF INFLOW.
TEMPS THERE RIGHT NOW ARE ABOUT 10F ABOVE AVERAGES. THEREFORE...THE
TEMPS SHOULD ROUND OUT TO 80F OR BETTER IN MANY LOCATIONS TUESDAY.
ALONG WITH THE WARM TEMPERATURES WILL BE MOIST AIR WITH DEWPOINTS
IN THE 60S. THIS WARM...MOIST AIR...ALONG WITH A WEAKENING RIDGE
WILL CREATE A GOOD SITUATION FOR SCT AFTN CONVECTION.

THE MEDIUM RANGE GUIDANCE CONTINUES TO ADVERTISE A RATHER
UNSETTLED PERIOD FOR MUCH OF THE UPCOMING WEEK.

WE ARE AND WILL REMAIN BASICALLY UNDER A MEAN UPPER RIDGE...BUT
THE PROBLEM WILL BE A WEAK FRONTAL SYSTEM THAT WILL BE MEANDERING
THROUGH CENTRAL PA FOR MUCH OF THE TIME INTO LATE WEEK. SO WHILE
THERE IS SUPPORT ALOFT FOR ORGANIZED PRECIP...THE SHOWERS WILL BE
TIED TO SMALL SCALE FEATURES THAT WILL BE HARD TO SEE MORE THAN A
DAY OR TWO DOWN THE ROAD. THE LOW LEVEL FORCING AND INCREASING
HUMIDITY/INSTABILITY WILL BRING SEVERAL CHANCES FOR MAINLY DIURNAL
SHOWERS AND THUNDERSTORMS.

THE FORECAST HAS A LOT OF REDUNDANCY IN IT...IMPLYING A PROLONGED
PERIOD OF RAIN/STORMS. THE REALITY IS LIKELY TO BE MORE LIKE A
PERIOD OF MAINLY CLOUDY SKIES BUT WITH SUNNY BREAKS DURING THE
DAY...ALONG WITH SHOWERS THAT WILL BE MOST LIKELY IN THE AFTERNOON
AND EVENING. A DIFFUSE FRONT WILL ATTEMPT TO PUSH NORTHWARD DURING
THE MIDDLE OF THE WEEK. WHERE THE FRONT WILL BE ON ANY GIVEN DAY
WILL HAVE MUCH TO DO WITH MESOSCALE INFLUENCES FROM ANY CONVECTION
THAT MANAGES TO FORM.

DESPITE AMPLE CLOUD COVER AND THE CHANCES FOR RAIN...TEMPERATURES
SHOULD REMAIN ABOVE NORMAL UNTIL AT LEAST LATE WEEK WHEN GUIDANCE
SUGGESTS WE FINALLY SEE A COLD FRONT MOVE THROUGH USHERING IN
MUCH COOLER AIR AND DRIER CONDITIONS.

&&

.AVIATION /08Z MONDAY THROUGH FRIDAY/...
A MOIST SERLY FLOW OFF OF THE ATLANTIC OCEAN WILL CONTINUE TO
PRODUCE WIDESPREAD STRATUS AND LIFR/IFR CIGS ACROSS CENTRAL PA
OVERNIGHT WITH CIGS BLO 1000 FT AT MOST AIRFIELDS. A BIT OF
DRIZZLE AND AREAS OF FOG WILL ALSO ADD TO LOWER VSBYS AT MANY SITES.
NEAR TERM MDL DATA INDICATING A NEARLY SATURATED SFC- 900MB LYR
ACROSS THE AREA TONIGHT.

SIGNIFICANT IMPROVEMENT IN FLYING CONDS IS EXPECTED LATER THIS MORNING/AFTER
SUNRISE...AS A WARM FRONT LIFTS THRU THE AREA AND SFC FLOW SHIFTS
TO THE SSW. MDL SOUNDINGS AND SREF DATA INDICATE PREDOMINATELY VFR
CONDS ARE LIKELY EVERYWHERE BY THE AFTN. HOWEVER...THERE IS A
SLIGHT CHC OF AN AFTN TSRA ACROSS THE W MTNS...WHICH COULD PRODUCE
A BRIEF VIS/CIG REDUCTION.

.OUTLOOK...
TUE-THU...LOW CLOUDS/FOG POSS EARLY. SCT PM THUNDERSTORM IMPACTS POSSIBLE.
FRI...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...LA CORTE/LAMBERT
NEAR TERM...DANGELO
SHORT TERM...DANGELO/LAMBERT
LONG TERM...LA CORTE/CERU
AVIATION...FITZGERALD/GARTNER

000
FXUS61 KCTP 200529
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
129 AM EDT MON MAY 20 2013

.SYNOPSIS...
HIGH PRESSURE OFF THE NEW ENGLAND COAST WILL MAINTAIN A MOIST
SOUTHEASTERLY FLOW OVER THE REGION THROUGH THE REST OF THE NIGHT.
A WARM FRONT WILL ATTEMPT TO MOVE THROUGH THE FORECAST AREA
MONDAY. IT SHOULD SUCCEED IN DOING SO...BRINGING INCREASING WARMTH
AND HUMIDITY TO THE REGION THROUGH MID-WEEK. EXPECT WELL ABOVE
NORMAL AFTERNOON TEMPERATURES TUESDAY AND WEDNESDAY. TEMPERATURES
WILL COOL BACK BELOW NORMAL WITH DRIER CONDITIONS BY THE WEEKEND.

&&

.NEAR TERM /UNTIL 8 AM THIS MORNING/...
THE PREPONDERANCE OF PARAMETERS PROCEED PER PRE-ESTABLISHED
PROGNOSTICATIONS. PREVIOUS FORECASTS SHALL PREVAIL.

THE REGION REMAINS STRONGLY COOL AIR DAMMED...WITH WIDESPREAD LOW
CLOUDS AND AREAS OF DRIZZLE AND VERY LIGHT RAIN. THIS WILL
CONTINUE OVERNIGHT. THE BLANKET OF CLOUDS AND RELATIVELY HIGH SFC
DEWPOINTS...IN MID 50S TO AROUND 60F WILL KEEP TEMPS 10-15F ABOVE
NORMAL OVERNIGHT.

&&

.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM TUESDAY/...
UPPER RIDGE WILL BE IN PLACE FROM THE OHIO VALLEY TO THE GULF COAST.
500 MB HEIGHTS WILL RISE SLIGHTLY /BY 10-20M/ DURING THE DAY
MONDAY...AS THE MEAN /AND INITIALLY SOUTHERLY/ 925-850 MB FLOW VEERS
AROUND TO THE WSW BY THE MIDDAY HOURS MONDAY.

LINGERING...EARLY MORNING LOW CLOUDS AND FOG SHOULD BE ERODED RATHER
QUICKLY BETWEEN 14-17Z MONDAY...WITH PARTLY SUNNY SKIES IN MOST
AREAS FOR THE AFTERNOON HOURS. DEEP VERTICAL MIXING OF THE WARM
/PLUS 14-15C/ AIR AT 850 MB WILL YIELD ABOVE NORMAL AFTERNOON TEMPS
IN THE MID 70S TO AROUND 80F.

SOME OF THE DEEPER VALLEYS EAST OF THE LAUREL HIGHLANDS...WHERE THE
GREATEST COMPRESSIONAL WARMING WILL OCCUR VIA AN ORTHOGONAL LLVL WSW
FLOW...COULD SOAR INTO THE LOWERS 80S IF AMPLE CLEARING OCCURS AND
SCTD SHOWERS/TSRA HOLD OFF UNTIL AFTER 20Z.

POPS FOR SCTD SHOWERS AND ISOLATED TSRA FOR MONDAY AFTERNOON WILL BE
JUST UNDER 30 PERCENT ACROSS THE NW ZONES...AND 40-45 PERCENT IN THE
SE.

WEAK LOW PRESSURE ALOFT WILL FINALLY DISAPPEAR MONDAY NIGHT AS IT
PASSES OVERHEAD. UPSTREAM CONVECTION WILL BE DROPPING ACROSS THE
GREAT LAKES AND WILL ONLY PROLONG THE CLOUDY/SHOWERY FORECAST FOR
LATE THIS PERIOD.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
ON TUESDAY...WE SHOULD ENTER THE WARM SECTOR AHEAD OF THE STORM
LANGUISHING OVER THE PLAINS/MIDWEST/UPPER LAKES. THE WARM SECTOR
AIR WILL BE QUITE WARM FOR THE TIME OF YEAR...HAVING SPENT PLENTY
OF TIME COOKING OVER THE MS AND OH VALLEYS WITH GOOD GULF INFLOW.
TEMPS THERE RIGHT NOW ARE ABOUT 10F ABOVE AVERAGES. THEREFORE...THE
TEMPS SHOULD ROUND OUT TO 80F OR BETTER IN MANY LOCATIONS TUESDAY.
ALONG WITH THE WARM TEMPERATURES WILL BE MOIST AIR WITH DEWPOINTS
IN THE 60S. THIS WARM...MOIST AIR...ALONG WITH A WEAKENING RIDGE
WILL CREATE A GOOD SITUATION FOR SCT AFTN CONVECTION.

THE MEDIUM RANGE GUIDANCE CONTINUES TO ADVERTISE A RATHER
UNSETTLED PERIOD FOR MUCH OF THE UPCOMING WEEK.

WE ARE AND WILL REMAIN BASICALLY UNDER A MEAN UPPER RIDGE...BUT
THE PROBLEM WILL BE A WEAK FRONTAL SYSTEM THAT WILL BE MEANDERING
THROUGH CENTRAL PA FOR MUCH OF THE TIME INTO LATE WEEK. SO WHILE
THERE IS SUPPORT ALOFT FOR ORGANIZED PRECIP...THE SHOWERS WILL BE
TIED TO SMALL SCALE FEATURES THAT WILL BE HARD TO SEE MORE THAN A
DAY OR TWO DOWN THE ROAD. THE LOW LEVEL FORCING AND INCREASING
HUMIDITY/INSTABILITY WILL BRING SEVERAL CHANCES FOR MAINLY DIURNAL
SHOWERS AND THUNDERSTORMS.

THE FORECAST HAS A LOT OF REDUNDANCY IN IT...IMPLYING A PROLONGED
PERIOD OF RAIN/STORMS. THE REALITY IS LIKELY TO BE MORE LIKE A
PERIOD OF MAINLY CLOUDY SKIES BUT WITH SUNNY BREAKS DURING THE
DAY...ALONG WITH SHOWERS THAT WILL BE MOST LIKELY IN THE AFTERNOON
AND EVENING. A DIFFUSE FRONT WILL ATTEMPT TO PUSH NORTHWARD DURING
THE MIDDLE OF THE WEEK. WHERE THE FRONT WILL BE ON ANY GIVEN DAY
WILL HAVE MUCH TO DO WITH MESOSCALE INFLUENCES FROM ANY CONVECTION
THAT MANAGES TO FORM.

DESPITE AMPLE CLOUD COVER AND THE CHANCES FOR RAIN...TEMPERATURES
SHOULD REMAIN ABOVE NORMAL UNTIL AT LEAST LATE WEEK WHEN GUIDANCE
SUGGESTS WE FINALLY SEE A COLD FRONT MOVE THROUGH USHERING IN
MUCH COOLER AIR AND DRIER CONDITIONS.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
A MOIST SERLY FLOW OFF OF THE ATLANTIC OCEAN IS PRODUCING WIDESPREAD
STRATUS ACROSS CENTRAL PA LATE THIS EVENING WITH CIGS RANGING
MAINLY BTWN 500 AND 1000 FT. A BIT OF DIURNAL COOLING AND
RESULTING MOISTENING OF BLYR SHOULD RESULT IN WIDESPREAD IFR/LIFR
CIGS LATER TONIGHT...ALONG WITH A BIT OF DRIZZLE. NEAR TERM MDL
DATA INDICATING A NEARLY SATURATED SFC-900MB LYR ACROSS THE AREA
TONIGHT.

SIGNIFICANT IMPROVEMENT IN FLYING CONDS IS EXPECTED ON MONDAY...AS
A WARM FRONT LIFTS THRU THE AREA AND SFC FLOW SHIFTS TO THE SSW.
MDL SOUNDINGS AND SREF DATA INDICATE PREDOMINATELY VFR CONDS ARE
LIKELY EVERYWHERE BY THE AFTN. HOWEVER...THERE IS A SLIGHT CHC OF
AN AFTN TSRA ACROSS THE W MTNS...WHICH COULD PRODUCE A BRIEF
VIS/CIG REDUCTION.

.OUTLOOK...
TUE-THU...LOW CLOUDS/FOG POSS EARLY. SCT PM THUNDERSTORM IMPACTS POSSIBLE.
FRI...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...LA CORTE/LAMBERT
NEAR TERM...DANGELO
SHORT TERM...DANGELO/LAMBERT
LONG TERM...LA CORTE/CERU
AVIATION...FITZGERALD

000
FXUS61 KCTP 200336
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1136 PM EDT SUN MAY 19 2013

.SYNOPSIS...
HIGH PRESSURE OFF THE NEW ENGLAND COAST WILL MAINTAIN A MOIST
SOUTHEASTERLY FLOW OVER THE REGION INTO MONDAY. A WARM FRONT WILL
MOVE THROUGH THE FORECAST AREA MONDAY...BRINGING INCREASING
WARMTH AND HUMIDITY TO THE REGION THROUGH THE MID-WEEK
PERIOD...WITH WELL ABOVE NORMAL AFTERNOON TEMPERATURES TUESDAY AND
WEDNESDAY. TEMPERATURES WILL COOL BACK BELOW NORMAL WITH DRIER
CONDITIONS LATER IN THE WEEK.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
THE REGION REMAINS STRONGLY COOL AIR DAMMED...WITH WIDESPREAD LOW
CLOUDS AND AREAS OF DRIZZLE AND VERY LIGHT RAIN. THIS WILL
CONTINUE OVERNIGHT. THE BLANKET OF CLOUDS AND RELATIVELY HIGH SFC
DEWPOINTS...IN MID 50S TO AROUND 60F WILL KEEP TEMPS 10-15F ABOVE
NORMAL OVERNIGHT.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
UPPER RIDGE WILL BE IN PLACE FROM THE OHIO VALLEY TO THE GULF COAST.
500 MB HEIGHTS WILL RISE SLIGHTLY /BY 10-20M/ DURING THE DAY
MONDAY...AS THE MEAN /AND INITIALLY SOUTHERLY/ 925-850 MB FLOW VEERS
AROUND TO THE WSW BY THE MIDDAY HOURS MONDAY.

LINGERING...EARLY MORNING LOW CLOUDS AND FOG SHOULD BE ERODED RATHER
QUICKLY BETWEEN 14-17Z MONDAY...WITH PARTLY SUNNY SKIES IN MOST
AREAS FOR THE AFTERNOON HOURS. DEEP VERTICAL MIXING OF THE WARM
/PLUS 14-15C/ AIR AT 850 MB WILL YIELD ABOVE NORMAL AFTERNOON TEMPS
IN THE MID 70S TO AROUND 80F.

SOME OF THE DEEPER VALLEYS EAST OF THE LAUREL HIGHLANDS...WHERE THE
GREATEST COMPRESSIONAL WARMING WILL OCCUR VIA AN ORTHOGONAL LLVL WSW
FLOW...COULD SOAR INTO THE LOWERS 80S IF AMPLE CLEARING OCCURS AND
SCTD SHOWERS/TSRA HOLD OFF UNTIL AFTER 20Z.

POPS FOR SCTD SHOWERS AND ISOLATED TSRA FOR MONDAY AFTERNOON WILL BE
JUST UNDER 30 PERCENT ACROSS THE NW ZONES...AND 40-45 PERCENT IN THE
SE.

WEAK LOW PRESSURE ALOFT WILL FINALLY DISAPPEAR MONDAY NIGHT AS IT
PASSES OVERHEAD. UPSTREAM CONVECTION WILL BE DROPPING ACROSS THE
GREAT LAKES AND WILL ONLY PROLONG THE CLOUDY/SHOWERY FORECAST FOR
LATE THIS PERIOD.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
ON TUESDAY...WE SHOULD ENTER THE WARM SECTOR AHEAD OF THE STORM
LANGUISHING OVER THE PLAINS/MIDWEST/UPPER LAKES. THE WARM SECTOR
AIR WILL BE QUITE WARM FOR THE TIME OF YEAR...HAVING SPENT PLENTY
OF TIME COOKING OVER THE MS AND OH VALLEYS WITH GOOD GULF INFLOW.
TEMPS THERE RIGHT NOW ARE ABOUT 10F ABOVE AVERAGES. THEREFORE...THE
TEMPS SHOULD ROUND OUT TO 80F OR BETTER IN MANY LOCATIONS TUESDAY.
ALONG WITH THE WARM TEMPERATURES WILL BE MOIST AIR WITH DEWPOINTS
IN THE 60S. THIS WARM...MOIST AIR...ALONG WITH A WEAKENING RIDGE
WILL CREATE A GOOD SITUATION FOR SCT AFTN CONVECTION.

THE MEDIUM RANGE GUIDANCE CONTINUES TO ADVERTISE A RATHER
UNSETTLED PERIOD FOR MUCH OF THE UPCOMING WEEK.

WE ARE AND WILL REMAIN BASICALLY UNDER A MEAN UPPER RIDGE...BUT
THE PROBLEM WILL BE A WEAK FRONTAL SYSTEM THAT WILL BE MEANDERING
THROUGH CENTRAL PA FOR MUCH OF THE TIME INTO LATE WEEK. SO WHILE
THERE IS SUPPORT ALOFT FOR ORGANIZED PRECIP...THE SHOWERS WILL BE
TIED TO SMALL SCALE FEATURES THAT WILL BE HARD TO SEE MORE THAN A
DAY OR TWO DOWN THE ROAD. THE LOW LEVEL FORCING AND INCREASING
HUMIDITY/INSTABILITY WILL BRING SEVERAL CHANCES FOR MAINLY DIURNAL
SHOWERS AND THUNDERSTORMS.

THE FORECAST HAS A LOT OF REDUNDANCY IN IT...IMPLYING A PROLONGED
PERIOD OF RAIN/STORMS. THE REALITY IS LIKELY TO BE MORE LIKE A
PERIOD OF MAINLY CLOUDY SKIES BUT WITH SUNNY BREAKS DURING THE
DAY...ALONG WITH SHOWERS THAT WILL BE MOST LIKELY IN THE AFTERNOON
AND EVENING. A DIFFUSE FRONT WILL ATTEMPT TO PUSH NORTHWARD DURING
THE MIDDLE OF THE WEEK. WHERE THE FRONT WILL BE ON ANY GIVEN DAY
WILL HAVE MUCH TO DO WITH MESOSCALE INFLUENCES FROM ANY CONVECTION
THAT MANAGES TO FORM.

DESPITE AMPLE CLOUD COVER AND THE CHANCES FOR RAIN...TEMPERATURES
SHOULD REMAIN ABOVE NORMAL UNTIL AT LEAST LATE WEEK WHEN GUIDANCE
SUGGESTS WE FINALLY SEE A COLD FRONT MOVE THROUGH USHERING IN
MUCH COOLER AIR AND DRIER CONDITIONS.

&&

.AVIATION /04Z MONDAY THROUGH FRIDAY/...
A MOIST SERLY FLOW OFF OF THE ATLANTIC OCEAN IS PRODUCING WIDESPREAD
STRATUS ACROSS CENTRAL PA LATE THIS EVENING WITH CIGS RANGING
MAINLY BTWN 500 AND 1000 FT. A BIT OF DIURNAL COOLING AND
RESULTING MOISTENING OF BLYR SHOULD RESULT IN WIDESPREAD IFR/LIFR
CIGS LATER TONIGHT...ALONG WITH A BIT OF DRIZZLE. NEAR TERM MDL
DATA INDICATING A NEARLY SATURATED SFC-900MB LYR ACROSS THE AREA
TONIGHT.

SIGNIFICANT IMPROVEMENT IN FLYING CONDS IS EXPECTED ON MONDAY...AS
A WARM FRONT LIFTS THRU THE AREA AND SFC FLOW SHIFTS TO THE SSW.
MDL SOUNDINGS AND SREF DATA INDICATE PREDOMINATELY VFR CONDS ARE
LIKELY EVERYWHERE BY THE AFTN. HOWEVER...THERE IS A SLIGHT CHC OF
AN AFTN TSRA ACROSS THE W MTNS...WHICH COULD PRODUCE A BRIEF
VIS/CIG REDUCTION.

.OUTLOOK...
TUE-THU...LOW CLOUDS/FOG POSS EARLY. SCT PM THUNDERSTORM IMPACTS POSSIBLE.
FRI...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...LA CORTE/LAMBERT
NEAR TERM...LA CORTE/LAMBERT
SHORT TERM...DANGELO/LAMBERT
LONG TERM...LA CORTE/CERU
AVIATION...FITZGERALD

000
FXUS61 KCTP 200222
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1022 PM EDT SUN MAY 19 2013

.SYNOPSIS...
HIGH PRESSURE OFF THE NEW ENGLAND COAST WILL MAINTAIN A MOIST
SOUTHEASTERLY FLOW OVER THE REGION INTO MONDAY. A WARM FRONT WILL
MOVE THROUGH THE FORECAST AREA MONDAY...BRINGING INCREASING
WARMTH AND HUMIDITY TO THE REGION THROUGH THE MID-WEEK
PERIOD...WITH WELL ABOVE NORMAL AFTERNOON TEMPERATURES TUESDAY AND
WEDNESDAY. TEMPERATURES WILL COOL BACK BELOW NORMAL WITH DRIER
CONDITIONS LATER IN THE WEEK.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...

THE REGION REMAINS STRONGLY COOL AIR DAMMED...WITH WIDESPREAD LOW
CLOUDS AND AREAS OF DRIZZLE AND VERY LIGHT RAIN. THIS WILL
CONTINUE OVERNIGHT. THE BLANKET OF CLOUDS AND RELATIVELY HIGH SFC
DEWPOINTS...IN MID 50S TO AROUND 60F WILL KEEP TEMPS 10-15F ABOVE
NORMAL OVERNIGHT.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
UPPER RIDGE WILL BE IN PLACE FROM THE OHIO VALLEY TO THE GULF COAST.
500 MB HEIGHTS WILL RISE SLIGHTLY /BY 10-20M/ DURING THE DAY
MONDAY...AS THE MEAN /AND INITIALLY SOUTHERLY/ 925-850 MB FLOW VEERS
AROUND TO THE WSW BY THE MIDDAY HOURS MONDAY.

LINGERING...EARLY MORNING LOW CLOUDS AND FOG SHOULD BE ERODED RATHER
QUICKLY BETWEEN 14-17Z MONDAY...WITH PARTLY SUNNY SKIES IN MOST
AREAS FOR THE AFTERNOON HOURS. DEEP VERTICAL MIXING OF THE WARM
/PLUS 14-15C/ AIR AT 850 MB WILL YIELD ABOVE NORMAL AFTERNOON TEMPS
IN THE MID 70S TO AROUND 80F.

SOME OF THE DEEPER VALLEYS EAST OF THE LAUREL HIGHLANDS...WHERE THE
GREATEST COMPRESSIONAL WARMING WILL OCCUR VIA AN ORTHOGONAL LLVL WSW
FLOW...COULD SOAR INTO THE LOWERS 80S IF AMPLE CLEARING OCCURS AND
SCTD SHOWERS/TSRA HOLD OFF UNTIL AFTER 20Z.

POPS FOR SCTD SHOWERS AND ISOLATED TSRA FOR MONDAY AFTERNOON WILL BE
JUST UNDER 30 PERCENT ACROSS THE NW ZONES...AND 40-45 PERCENT IN THE
SE.

WEAK LOW PRESSURE ALOFT WILL FINALLY DISAPPEAR MONDAY NIGHT AS IT
PASSES OVERHEAD. UPSTREAM CONVECTION WILL BE DROPPING ACROSS THE
GREAT LAKES AND WILL ONLY PROLONG THE CLOUDY/SHOWERY FORECAST FOR
LATE THIS PERIOD.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
ON TUESDAY...WE SHOULD ENTER THE WARM SECTOR AHEAD OF THE STORM
LANGUISHING OVER THE PLAINS/MIDWEST/UPPER LAKES. THE WARM SECTOR
AIR WILL BE QUITE WARM FOR THE TIME OF YEAR...HAVING SPENT PLENTY
OF TIME COOKING OVER THE MS AND OH VALLEYS WITH GOOD GULF INFLOW.
TEMPS THERE RIGHT NOW ARE ABOUT 10F ABOVE AVERAGES. THEREFORE...THE
TEMPS SHOULD ROUND OUT TO 80F OR BETTER IN MANY LOCATIONS TUESDAY.
ALONG WITH THE WARM TEMPERATURES WILL BE MOIST AIR WITH DEWPOINTS
IN THE 60S. THIS WARM...MOIST AIR...ALONG WITH A WEAKENING RIDGE
WILL CREATE A GOOD SITUATION FOR SCT AFTN CONVECTION.

THE MEDIUM RANGE GUIDANCE CONTINUES TO ADVERTISE A RATHER
UNSETTLED PERIOD FOR MUCH OF THE UPCOMING WEEK.

WE ARE AND WILL REMAIN BASICALLY UNDER A MEAN UPPER RIDGE...BUT
THE PROBLEM WILL BE A WEAK FRONTAL SYSTEM THAT WILL BE MEANDERING
THROUGH CENTRAL PA FOR MUCH OF THE TIME INTO LATE WEEK. SO WHILE
THERE IS SUPPORT ALOFT FOR ORGANIZED PRECIP...THE SHOWERS WILL BE
TIED TO SMALL SCALE FEATURES THAT WILL BE HARD TO SEE MORE THAN A
DAY OR TWO DOWN THE ROAD. THE LOW LEVEL FORCING AND INCREASING
HUMIDITY/INSTABILITY WILL BRING SEVERAL CHANCES FOR MAINLY DIURNAL
SHOWERS AND THUNDERSTORMS.

THE FORECAST HAS A LOT OF REDUNDANCY IN IT...IMPLYING A PROLONGED
PERIOD OF RAIN/STORMS. THE REALITY IS LIKELY TO BE MORE LIKE A
PERIOD OF MAINLY CLOUDY SKIES BUT WITH SUNNY BREAKS DURING THE
DAY...ALONG WITH SHOWERS THAT WILL BE MOST LIKELY IN THE AFTERNOON
AND EVENING. A DIFFUSE FRONT WILL ATTEMPT TO PUSH NORTHWARD DURING
THE MIDDLE OF THE WEEK. WHERE THE FRONT WILL BE ON ANY GIVEN DAY
WILL HAVE MUCH TO DO WITH MESOSCALE INFLUENCES FROM ANY CONVECTION
THAT MANAGES TO FORM.

DESPITE AMPLE CLOUD COVER AND THE CHANCES FOR RAIN...TEMPERATURES
SHOULD REMAIN ABOVE NORMAL UNTIL AT LEAST LATE WEEK WHEN GUIDANCE
SUGGESTS WE FINALLY SEE A COLD FRONT MOVE THROUGH USHERING IN
MUCH COOLER AIR AND DRIER CONDITIONS.

&&

.AVIATION /02Z MONDAY THROUGH FRIDAY/...
A MOIST SERLY FLOW OFF OF THE ATLANTIC OCEAN IS PRODUCING WIDESPREAD
STRATUS ACROSS CENTRAL PA WITH CIGS RANGING BTWN 500 AND 1500 FT.
A BIT OF DIURNAL COOLING AND RESULTING MOISTENING OF BLYR SHOULD
RESULT IN WIDESPREAD IFR/LIFR CIGS LATER TONIGHT...ALONG WITH A
BIT OF DRIZZLE. NEAR TERM MDL DATA INDICATING A NEARLY SATURATED
SFC-900MB LYR ACROSS THE AREA TONIGHT.

SIGNIFICANT IMPROVEMENT IN FLYING CONDS IS EXPECTED ON MONDAY...AS
A WARM FRONT LIFTS THRU THE AREA AND SFC FLOW SHIFTS TO THE SSW.
MDL SOUNDINGS AND SREF DATA INDICATE PREDOMINATELY VFR CONDS ARE
LIKELY EVERYWHERE BY THE AFTN. HOWEVER...THERE IS A SLIGHT CHC OF
AN AFTN TSRA ACROSS THE W MTNS...WHICH COULD PRODUCE A BRIEF
VIS/CIG REDUCTION.

.OUTLOOK...
TUE-THU...LOW CLOUDS/FOG POSS EARLY. SCT PM THUNDERSTORM IMPACTS POSSIBLE.
FRI...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...LA CORTE/LAMBERT
NEAR TERM...LA CORTE/LAMBERT
SHORT TERM...DANGELO/LAMBERT
LONG TERM...LA CORTE/CERU
AVIATION...FITZGERALD

000
FXUS61 KCTP 200015
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
815 PM EDT SUN MAY 19 2013

.SYNOPSIS...
HIGH PRESSURE OFF THE NEW ENGLAND COAST WILL MAINTAIN A MOIST
SOUTHEASTERLY FLOW OVER THE REGION INTO MONDAY. A WARM FRONT WILL
MOVE THROUGH THE FORECAST AREA MONDAY...BRINGING INCREASING
WARMTH AND HUMIDITY TO THE REGION THROUGH THE MID-WEEK
PERIOD...WITH WELL ABOVE NORMAL AFTERNOON TEMPERATURES TUESDAY AND
WEDNESDAY. TEMPERATURES WILL COOL BACK BELOW NORMAL WITH DRIER
CONDITIONS LATER IN THE WEEK.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
THE REGION REMAINS STRONGLY COOL AIR DAMMED...WITH WIDESPREAD LOW
CEILINGS AND AREAS OF DRIZZLE AND VERY LIGHT RAIN. THIS WILL
CONTINUE OVERNIGHT. THE BLANKET OF CLOUDS AND RELATIVELY HIGH
SFC DEWPOINTS...IN MID 50S TO AROUND 60F WILL KEEP TEMPS 10-15F
ABOVE CLIMO NORMALS OVERNIGHT.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
UPPER RIDGE WILL BE IN PLACE FROM THE OHIO VALLEY TO THE GULF COAST.
500 MB HEIGHTS WILL RISE SLIGHTLY /BY 10-20M/ DURING THE DAY
MONDAY...AS THE MEAN /AND INITIALLY SOUTHERLY/ 925-850 MB FLOW VEERS
AROUND TO THE WSW BY THE MIDDAY HOURS MONDAY.

LINGERING...EARLY MORNING LOW CLOUDS AND FOG SHOULD BE ERODED RATHER
QUICKLY BETWEEN 14-17Z MONDAY...WITH PARTLY SUNNY SKIES IN MOST
AREAS FOR THE AFTERNOON HOURS. DEEP VERTICAL MIXING OF THE WARM
/PLUS 14-15C/ AIR AT 850 MB WILL YIELD ABOVE NORMAL AFTERNOON TEMPS
IN THE MID 70S TO AROUND 80F.

SOME OF THE DEEPER VALLEYS EAST OF THE LAUREL HIGHLANDS...WHERE THE
GREATEST COMPRESSIONAL WARMING WILL OCCUR VIA AN ORTHOGONAL LLVL WSW
FLOW...COULD SOAR INTO THE LOWERS 80S IF AMPLE CLEARING OCCURS AND
SCTD SHOWERS/TSRA HOLD OFF UNTIL AFTER 20Z.

POPS FOR SCTD SHOWERS AND ISOLATED TSRA FOR MONDAY AFTERNOON WILL BE
JUST UNDER 30 PERCENT ACROSS THE NW ZONES...AND 40-45 PERCENT IN THE
SE.

WEAK LOW PRESSURE ALOFT WILL FINALLY DISAPPEAR MONDAY NIGHT AS IT
PASSES OVERHEAD. UPSTREAM CONVECTION WILL BE DROPPING ACROSS THE
GREAT LAKES AND WILL ONLY PROLONG THE CLOUDY/SHOWERY FORECAST FOR
LATE THIS PERIOD.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
ON TUESDAY...WE SHOULD ENTER THE WARM SECTOR AHEAD OF THE STORM
LANGUISHING OVER THE PLAINS/MIDWEST/UPPER LAKES. THE WARM SECTOR
AIR WILL BE QUITE WARM FOR THE TIME OF YEAR...HAVING SPENT PLENTY
OF TIME COOKING OVER THE MS AND OH VALLEYS WITH GOOD GULF INFLOW.
TEMPS THERE RIGHT NOW ARE ABOUT 10F ABOVE AVERAGES. THEREFORE...THE
TEMPS SHOULD ROUND OUT TO 80F OR BETTER IN MANY LOCATIONS TUESDAY.
ALONG WITH THE WARM TEMPERATURES WILL BE MOIST AIR WITH DEWPOINTS
IN THE 60S. THIS WARM...MOIST AIR...ALONG WITH A WEAKENING RIDGE
WILL CREATE A GOOD SITUATION FOR SCT AFTN CONVECTION.

THE MEDIUM RANGE GUIDANCE CONTINUES TO ADVERTISE A RATHER
UNSETTLED PERIOD FOR MUCH OF THE UPCOMING WEEK.

WE ARE AND WILL REMAIN BASICALLY UNDER A MEAN UPPER RIDGE...BUT
THE PROBLEM WILL BE A WEAK FRONTAL SYSTEM THAT WILL BE MEANDERING
THROUGH CENTRAL PA FOR MUCH OF THE TIME INTO LATE WEEK. SO WHILE
THERE IS SUPPORT ALOFT FOR ORGANIZED PRECIP...THE SHOWERS WILL BE
TIED TO SMALL SCALE FEATURES THAT WILL BE HARD TO SEE MORE THAN A
DAY OR TWO DOWN THE ROAD. THE LOW LEVEL FORCING AND INCREASING
HUMIDITY/INSTABILITY WILL BRING SEVERAL CHANCES FOR MAINLY DIURNAL
SHOWERS AND THUNDERSTORMS.

THE FORECAST HAS A LOT OF REDUNDANCY IN IT...IMPLYING A PROLONGED
PERIOD OF RAIN/STORMS. THE REALITY IS LIKELY TO BE MORE LIKE A
PERIOD OF MAINLY CLOUDY SKIES BUT WITH SUNNY BREAKS DURING THE
DAY...ALONG WITH SHOWERS THAT WILL BE MOST LIKELY IN THE AFTERNOON
AND EVENING. A DIFFUSE FRONT WILL ATTEMPT TO PUSH NORTHWARD DURING
THE MIDDLE OF THE WEEK. WHERE THE FRONT WILL BE ON ANY GIVEN DAY
WILL HAVE MUCH TO DO WITH MESOSCALE INFLUENCES FROM ANY CONVECTION
THAT MANAGES TO FORM.

DESPITE AMPLE CLOUD COVER AND THE CHANCES FOR RAIN...TEMPERATURES
SHOULD REMAIN ABOVE NORMAL UNTIL AT LEAST LATE WEEK WHEN GUIDANCE
SUGGESTS WE FINALLY SEE A COLD FRONT MOVE THROUGH USHERING IN
MUCH COOLER AIR AND DRIER CONDITIONS.

&&

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
A MOIST SERLY FLOW OFF OF THE ATLANTIC OCEAN IS PRODUCING WIDESPREAD
STRATUS ACROSS CENTRAL PA WITH CIGS RANGING BTWN 500 AND 1500 FT.
A BIT OF DIURNAL COOLING AND RESULTING MOISTENING OF BLYR SHOULD
RESULT IN WIDESPREAD IFR/LIFR CIGS LATER TONIGHT...ALONG WITH A
BIT OF DRIZZLE. NEAR TERM MDL DATA INDICATING A NEARLY SATURATED
SFC-900MB LYR ACROSS THE AREA TONIGHT.

SIGNIFICANT IMPROVEMENT IN FLYING CONDS IS EXPECTED ON MONDAY...AS
A WARM FRONT LIFTS THRU THE AREA AND SFC FLOW SHIFTS TO THE SSW.
MDL SOUNDINGS AND SREF DATA INDICATE PREDOMINATELY VFR CONDS ARE
LIKELY EVERYWHERE BY THE AFTN. HOWEVER...THERE IS A SLIGHT CHC OF
AN AFTN TSRA ACROSS THE W MTNS...WHICH COULD PRODUCE A BRIEF
VIS/CIG REDUCTION.

.OUTLOOK...
TUE-THU...LOW CLOUDS/FOG POSS EARLY. SCT PM THUNDERSTORM IMPACTS POSSIBLE.
FRI...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...LA CORTE/LAMBERT
NEAR TERM...LA CORTE/LAMBERT
SHORT TERM...DANGELO/LAMBERT
LONG TERM...LA CORTE/CERU
AVIATION...FITZGERALD

000
FXUS61 KCTP 192336
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
736 PM EDT SUN MAY 19 2013

.SYNOPSIS...

HIGH PRESSURE OFF THE NEW ENGLAND COAST WILL MAINTAIN A MOIST
SOUTHEASTERLY FLOW OVER THE REGION INTO MONDAY. A WARM FRONT WILL
MOVE THROUGH THE FORECAST AREA MONDAY...BRINGING INCREASING
WARMTH AND HUMIDITY TO THE REGION THROUGH THE MID-WEEK
PERIOD...WITH WELL ABOVE NORMAL AFTERNOON TEMPERATURES TUESDAY AND
WEDNESDAY. TEMPERATURES WILL COOL BACK BELOW NORMAL WITH DRIER
CONDITIONS LATER IN THE WEEK.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...

THE REGION REMAINS STRONGLY COOL AIR DAMMED...WITH WIDESPREAD LOW
CEILINGS AND AREAS OF DRIZZLE AND VERY LIGHT RAIN. THIS WILL
CONTINUE OVERNIGHT. THE BLANKET OF CLOUDS AND RELATIVELY HIGH
SFC DEWPOINTS...IN MID 50S TO AROUND 60F WILL KEEP TEMPS 10-15F
ABOVE CLIMO NORMALS OVERNIGHT.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
UPPER RIDGE WILL BE IN PLACE FROM THE OHIO VALLEY TO THE GULF COAST.
500 MB HEIGHTS WILL RISE SLIGHTLY /BY 10-20M/ DURING THE DAY
MONDAY...AS THE MEAN /AND INITIALLY SOUTHERLY/ 925-850 MB FLOW VEERS
AROUND TO THE WSW BY THE MIDDAY HOURS MONDAY.

LINGERING...EARLY MORNING LOW CLOUDS AND FOG SHOULD BE ERODED RATHER
QUICKLY BETWEEN 14-17Z MONDAY...WITH PARTLY SUNNY SKIES IN MOST
AREAS FOR THE AFTERNOON HOURS. DEEP VERTICAL MIXING OF THE WARM
/PLUS 14-15C/ AIR AT 850 MB WILL YIELD ABOVE NORMAL AFTERNOON TEMPS
IN THE MID 70S TO AROUND 80F.

SOME OF THE DEEPER VALLEYS EAST OF THE LAUREL HIGHLANDS...WHERE THE
GREATEST COMPRESSIONAL WARMING WILL OCCUR VIA AN ORTHOGONAL LLVL WSW
FLOW...COULD SOAR INTO THE LOWERS 80S IF AMPLE CLEARING OCCURS AND
SCTD SHOWERS/TSRA HOLD OFF UNTIL AFTER 20Z.

POPS FOR SCTD SHOWERS AND ISOLATED TSRA FOR MONDAY AFTERNOON WILL BE
JUST UNDER 30 PERCENT ACROSS THE NW ZONES...AND 40-45 PERCENT IN THE
SE.

WEAK LOW PRESSURE ALOFT WILL FINALLY DISAPPEAR MONDAY NIGHT AS IT
PASSES OVERHEAD. UPSTREAM CONVECTION WILL BE DROPPING ACROSS THE
GREAT LAKES AND WILL ONLY PROLONG THE CLOUDY/SHOWERY FORECAST FOR
LATE THIS PERIOD.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
ON TUESDAY...WE SHOULD ENTER THE WARM SECTOR AHEAD OF THE STORM
LANGUISHING OVER THE PLAINS/MIDWEST/UPPER LAKES. THE WARM SECTOR
AIR WILL BE QUITE WARM FOR THE TIME OF YEAR...HAVING SPENT PLENTY
OF TIME COOKING OVER THE MS AND OH VALLEYS WITH GOOD GULF INFLOW.
TEMPS THERE RIGHT NOW ARE ABOUT 10F ABOVE AVERAGES. THEREFORE...THE
TEMPS SHOULD ROUND OUT TO 80F OR BETTER IN MANY LOCATIONS TUESDAY.
ALONG WITH THE WARM TEMPERATURES WILL BE MOIST AIR WITH DEWPOINTS
IN THE 60S. THIS WARM...MOIST AIR...ALONG WITH A WEAKENING RIDGE
WILL CREATE A GOOD SITUATION FOR SCT AFTN CONVECTION.

THE MEDIUM RANGE GUIDANCE CONTINUES TO ADVERTISE A RATHER
UNSETTLED PERIOD FOR MUCH OF THE UPCOMING WEEK.

WE ARE AND WILL REMAIN BASICALLY UNDER A MEAN UPPER RIDGE...BUT
THE PROBLEM WILL BE A WEAK FRONTAL SYSTEM THAT WILL BE MEANDERING
THROUGH CENTRAL PA FOR MUCH OF THE TIME INTO LATE WEEK. SO WHILE
THERE IS SUPPORT ALOFT FOR ORGANIZED PRECIP...THE SHOWERS WILL BE
TIED TO SMALL SCALE FEATURES THAT WILL BE HARD TO SEE MORE THAN A
DAY OR TWO DOWN THE ROAD. THE LOW LEVEL FORCING AND INCREASING
HUMIDITY/INSTABILITY WILL BRING SEVERAL CHANCES FOR MAINLY DIURNAL
SHOWERS AND THUNDERSTORMS.

THE FORECAST HAS A LOT OF REDUNDANCY IN IT...IMPLYING A PROLONGED
PERIOD OF RAIN/STORMS. THE REALITY IS LIKELY TO BE MORE LIKE A
PERIOD OF MAINLY CLOUDY SKIES BUT WITH SUNNY BREAKS DURING THE
DAY...ALONG WITH SHOWERS THAT WILL BE MOST LIKELY IN THE AFTERNOON
AND EVENING. A DIFFUSE FRONT WILL ATTEMPT TO PUSH NORTHWARD DURING
THE MIDDLE OF THE WEEK. WHERE THE FRONT WILL BE ON ANY GIVEN DAY
WILL HAVE MUCH TO DO WITH MESOSCALE INFLUENCES FROM ANY CONVECTION
THAT MANAGES TO FORM.

DESPITE AMPLE CLOUD COVER AND THE CHANCES FOR RAIN...TEMPERATURES
SHOULD REMAIN ABOVE NORMAL UNTIL AT LEAST LATE WEEK WHEN GUIDANCE
SUGGESTS WE FINALLY SEE A COLD FRONT MOVE THROUGH USHERING IN
MUCH COOLER AIR AND DRIER CONDITIONS.

&&

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
A WAVY FRONTAL BOUNDARY JUST TO OUR SOUTH WILL SLOWLY RETURN
NORTHWARD ACROSS PENNSYLVANIA AS A WARM FRONT LATE TODAY INTO MONDAY.

WIDESPREAD IFR SOUTH /AND LOW-END MVFR CIGS CENTRAL AND NORTH/ WITH
GENERALLY 7-10SM VSBYS WILL CONTINUE THROUGH THE AFTERNOON HOURS.
LOWEST CONDITIONS WILL BE FOUND ACROSS THE SOUTHERN THIRD OF PENN.

RIDGE TOPS AOA APPROX 1900 FT MSL WILL CONTINUE TO BE SHROUDED IN
THE LOW CLOUDS/FOG THROUGH AT LEAST EARLY THIS AFTERNOON.

AREAS OF DRIZZLE AND ISOLATED TO SCATTERED -SHRA WILL BE MOVING BACK
TOWARD PA FROM THE SOUTH THIS AFTERNOON AS WELL. THE HIGHEST
PROBABILITY FOR THE LIGHT QPF WILL BE ACROSS THE SOUTHERN PA TAF
AIRFIELDS /KJST/LNS/MDT/CXY.

AFTER SOME MINOR...BRIEF IMPROVEMENT TO CIGS AND VSBYS THIS
AFTERNOON...CONDITIONS QUICKLY SLIDE DOWN TO WIDESPREAD IFR
BEGINNING LATER THIS EVE AND CONTINUING UNTIL 13-15Z MONDAY.

A RATHER UNSETTLED AND OCCASIONALLY WET PATTERN IS EXPECTED FOR
MONDAY AFTERNOON THROUGH THURSDAY...WITH DAILY CHC/S FOR CONVECTIVE
PCPN FOCUSED DURING THE AFTERNOON/EARLY EVENING /AND ASSOCD
RESTRICTIONS/.

.OUTLOOK...
MON-THU...AREAS OF EARLY MORNING IFR CONDITIONS IN STRATUS AND
FOG...TRANSITIONING TO VFR-MVFR WITH SCT PM THUNDERSTORM IMPACTS
EACH DAY.

FRI-SAT...MAINLY VFR. PATCHY MVFR TO IFR CIGS POSSIBLE 09-13Z BOTH
DAYS.

&&

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

&&

$$
SYNOPSIS...LA CORTE/LAMBERT
NEAR TERM...LA CORTE/LAMBERT
SHORT TERM...DANGELO/LAMBERT
LONG TERM...LA CORTE/CERU
AVIATION...FITZGERALD/LAMBERT

000
FXUS61 KCTP 192239
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
639 PM EDT SUN MAY 19 2013

.SYNOPSIS...
HIGH PRESSURE OVER NORTHERN NEW ENGLAND AND THE MOUTH OF THE ST.
LAWRENCE LATE TODAY WILL SLIDE TO THE EAST OVERNIGHT. A DEEP
SOUTHERLY FLOW IN THE WAKE OF THIS HIGH WILL BRING INCREASING WARMTH
AND HUMIDITY TO THE REGION THROUGH THE MID-WEEK PERIOD...WITH WELL
ABOVE NORMAL AFTERNOON TEMPERATURES TUESDAY AND WEDNESDAY. SCATTERED
SHOWERS AND THUNDERSTORMS WILL OCCUR EACH AFTERNOON THROUGH THURSDAY
AS A STORM SYSTEM CURRENTLY OVER THE CENTRAL PLAINS INCHES EASTWARD.
TEMPERATURES WILL COOL BACK BELOW NORMAL WITH DRIER CONDITIONS FOR
FRIDAY AND SATURDAY.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
A MOIST SOUTHEASTERLY FLOW NEAR THE SFC AND PLUME OF ANOMALOUSLY
HIGH PWAT AIR /1.5-1.75 INCHES/ MOVING INTO THE REGION FROM THE
SOUTH WILL CONTINUE TO LOCK IN THICK CLOUD COVER ACROSS PRACTICALLY
ALL OF THE CWA FOR THE REST OF TODAY.

PORTIONS OF THE NW MTNS WILL CONTINUE TO SEE PERIODS OF SUNSHINE
THROUGH THE REMAINDER OF THIS AFTERNOON...WITHIN THE VERY TIGHT
GRADIENT OF 925-850 MB THETA-E...AND AIDED BY LLVL DOWNSLOPING TO
THE WEST OF THE SPINE OF THE APPALACHIANS.

THE BASE OF THE THICK STRATUS/STRATOCU DECK WILL LIFT VERY LITTLE
FROM THEIR 18Z LEVELS AND CONTINUE TO SHROUD THE HIGHER RIDGE TOPS
THROUGH THIS EVENING....BEFORE GRADUALLY LOWERING DOWN THE SLOPES
SIMILAR TO LAST NIGHT.

WEAK FORCING IN THE FORM OF VERY GENTLE ISENTROPIC UPGLIDE FROM THE
SOUTH TO SSW WITHIN THE I300-310K THETA CHANNEL WILL HELP TO PRODUCE
A FEW LIGHT SHOWERS /OR MORE LIKELY AREAS OF LIGHT DRIZZLE/ THAT
WILL DRIFT NNE ACROSS THE FCST AREA THIS AFTERNOON THROUGH TONIGHT.

THE CLOUDS WILL KEEP AFTERNOON TEMPS ON THE COOL SIDE AND WELL BELOW
NORMALS ACROSS MOST OF THE AREA. JUST THOSE LUCKY FEW PLACES OVER
THE NORTHWEST MTNS COULD MEET OR EXCEED CLIMO HIGHS. MAX TEMPS WILL
BE MAINLY IN THE MID 60S...BUT SHOULD HOLD AOB 60F ACROSS SOME OF
THE EASTERN MTNS.

THIS BLANKET OF CLOUDS /AND RELATIVELY HIGH SFC DEWPOINTS...IN MID
50S TO AROUND 60F/ WILL KEEP TEMPS 10-15F ABOVE CLIMO NORMALS
OVERNIGHT.

ANY MEASURABLE RAINFALL TONIGHT WILL BE LIMITED TO SEVERAL
HUNDREDTHS OF AN INCH OR LESS.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
UPPER RIDGE WILL BE IN PLACE FROM THE OHIO VALLEY TO THE GULF COAST.
500 MB HEIGHTS WILL RISE SLIGHTLY /BY 10-20M/ DURING THE DAY
MONDAY...AS THE MEAN /AND INITIALLY SOUTHERLY/ 925-850 MB FLOW VEERS
AROUND TO THE WSW BY THE MIDDAY HOURS MONDAY.

LINGERING...EARLY MORNING LOW CLOUDS AND FOG SHOULD BE ERODED RATHER
QUICKLY BETWEEN 14-17Z MONDAY...WITH PARTLY SUNNY SKIES IN MOST
AREAS FOR THE AFTERNOON HOURS. DEEP VERTICAL MIXING OF THE WARM
/PLUS 14-15C/ AIR AT 850 MB WILL YIELD ABOVE NORMAL AFTERNOON TEMPS
IN THE MID 70S TO AROUND 80F.

SOME OF THE DEEPER VALLEYS EAST OF THE LAUREL HIGHLANDS...WHERE THE
GREATEST COMPRESSIONAL WARMING WILL OCCUR VIA AN ORTHOGONAL LLVL WSW
FLOW...COULD SOAR INTO THE LOWERS 80S IF AMPLE CLEARING OCCURS AND
SCTD SHOWERS/TSRA HOLD OFF UNTIL AFTER 20Z.

POPS FOR SCTD SHOWERS AND ISOLATED TSRA FOR MONDAY AFTERNOON WILL BE
JUST UNDER 30 PERCENT ACROSS THE NW ZONES...AND 40-45 PERCENT IN THE
SE.

WEAK LOW PRESSURE ALOFT WILL FINALLY DISAPPEAR MONDAY NIGHT AS IT
PASSES OVERHEAD. UPSTREAM CONVECTION WILL BE DROPPING ACROSS THE
GREAT LAKES AND WILL ONLY PROLONG THE CLOUDY/SHOWERY FORECAST FOR
LATE THIS PERIOD.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
ON TUESDAY...WE SHOULD ENTER THE WARM SECTOR AHEAD OF THE STORM
LANGUISHING OVER THE PLAINS/MIDWEST/UPPER LAKES. THE WARM SECTOR
AIR WILL BE QUITE WARM FOR THE TIME OF YEAR...HAVING SPENT PLENTY
OF TIME COOKING OVER THE MS AND OH VALLEYS WITH GOOD GULF INFLOW.
TEMPS THERE RIGHT NOW ARE ABOUT 10F ABOVE AVERAGES. THEREFORE...THE
TEMPS SHOULD ROUND OUT TO 80F OR BETTER IN MANY LOCATIONS TUESDAY.
ALONG WITH THE WARM TEMPERATURES WILL BE MOIST AIR WITH DEWPOINTS
IN THE 60S. THIS WARM...MOIST AIR...ALONG WITH A WEAKENING RIDGE
WILL CREATE A GOOD SITUATION FOR SCT AFTN CONVECTION.

THE MEDIUM RANGE GUIDANCE CONTINUES TO ADVERTISE A RATHER
UNSETTLED PERIOD FOR MUCH OF THE UPCOMING WEEK.

WE ARE AND WILL REMAIN BASICALLY UNDER A MEAN UPPER RIDGE...BUT
THE PROBLEM WILL BE A WEAK FRONTAL SYSTEM THAT WILL BE MEANDERING
THROUGH CENTRAL PA FOR MUCH OF THE TIME INTO LATE WEEK. SO WHILE
THERE IS SUPPORT ALOFT FOR ORGANIZED PRECIP...THE SHOWERS WILL BE
TIED TO SMALL SCALE FEATURES THAT WILL BE HARD TO SEE MORE THAN A
DAY OR TWO DOWN THE ROAD. THE LOW LEVEL FORCING AND INCREASING
HUMIDITY/INSTABILITY WILL BRING SEVERAL CHANCES FOR MAINLY DIURNAL
SHOWERS AND THUNDERSTORMS.

THE FORECAST HAS A LOT OF REDUNDANCY IN IT...IMPLYING A PROLONGED
PERIOD OF RAIN/STORMS. THE REALITY IS LIKELY TO BE MORE LIKE A
PERIOD OF MAINLY CLOUDY SKIES BUT WITH SUNNY BREAKS DURING THE
DAY...ALONG WITH SHOWERS THAT WILL BE MOST LIKELY IN THE AFTERNOON
AND EVENING. A DIFFUSE FRONT WILL ATTEMPT TO PUSH NORTHWARD DURING
THE MIDDLE OF THE WEEK. WHERE THE FRONT WILL BE ON ANY GIVEN DAY
WILL HAVE MUCH TO DO WITH MESOSCALE INFLUENCES FROM ANY CONVECTION
THAT MANAGES TO FORM.

DESPITE AMPLE CLOUD COVER AND THE CHANCES FOR RAIN...TEMPERATURES
SHOULD REMAIN ABOVE NORMAL UNTIL AT LEAST LATE WEEK WHEN GUIDANCE
SUGGESTS WE FINALLY SEE A COLD FRONT MOVE THROUGH USHERING IN
MUCH COOLER AIR AND DRIER CONDITIONS.

&&

.AVIATION /22Z SUNDAY THROUGH FRIDAY/...
A MOIST SERLY FLOW OFF OF THE ATLANTIC OCEAN IS PRODUCING
WIDESPREAD STRATUS ACROSS CENTRAL PA WITH CIGS RANGING BTWN 500
AND 1500 FT. VISIBLE SATL IMAGERY SHOWING BFD BENEFITING FROM A
BIT OF SUBSIDENCE WEST OF THE SPINE OF THE APPALACHIANS WITH BRKS
IN THE OVERCAST. HOWEVER...A CONTINUED SE FLOW...COMBINED WITH A
BIT OF DIURNAL COOLING...SHOULD CAUSE CIGS TO LOWER AND EXPAND NW
INTO BFD LATER THIS EVENING.

OPER MDL SOUNDINGS AND SREF DATA SUPPORT WIDESPREAD IFR/LIFR CIGS
LATER TONIGHT...ALONG WITH A BIT OF DRIZZLE.

SIGNIFICANT IMPROVEMENT IN FLYING CONDS IS EXPECTED ON MONDAY...AS
A WARM FRONT LIFTS THRU THE AREA AND FLOW SHIFTS TO THE SSW. MDL
SOUNDINGS AND SREF DATA INDICATE PREDOMINATELY VFR CONDS ARE
LIKELY EVERYWHERE BY THE AFTN. HOWEVER...THERE IS A SLIGHT CHC OF
AN AFTN TSRA ACROSS THE W MTNS...WHICH COULD PRODUCE A BRIEF
VIS/CIG REDUCTION.

.OUTLOOK...
TUE-THU...AREAS OF EARLY MORNING IFR CONDITIONS IN STRATUS AND
FOG...TRANSITIONING TO VFR-MVFR WITH SCT PM THUNDERSTORM IMPACTS
EACH DAY.

FRI-SAT...MAINLY VFR. PATCHY MVFR TO IFR CIGS POSSIBLE 09-13Z BOTH
DAYS.

&&

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

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...DANGELO/LAMBERT
LONG TERM...LA CORTE/CERU
AVIATION...FITZGERALD/LAMBERT

000
FXUS61 KCTP 192010
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
410 PM EDT SUN MAY 19 2013

.SYNOPSIS...
HIGH PRESSURE OVER NORTHERN NEW ENGLAND AND THE MOUTH OF THE ST.
LAWRENCE LATE TODAY WILL SLIDE TO THE EAST OVERNIGHT. A DEEP
SOUTHERLY FLOW IN THE WAKE OF THIS HIGH WILL BRING INCREASING WARMTH
AND HUMIDITY TO THE REGION THROUGH THE MID-WEEK PERIOD...WITH WELL
ABOVE NORMAL AFTERNOON TEMPERATURES TUESDAY AND WEDNESDAY. SCATTERED
SHOWERS AND THUNDERSTORMS WILL OCCUR EACH AFTERNOON THROUGH THURSDAY
AS A STORM SYSTEM CURRENTLY OVER THE CENTRAL PLAINS INCHES EASTWARD.
TEMPERATURES WILL COOL BACK BELOW NORMAL WITH DRIER CONDITIONS FOR
FRIDAY AND SATURDAY.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
A MOIST SOUTHEASTERLY FLOW NEAR THE SFC AND PLUME OF ANOMALOUSLY
HIGH PWAT AIR /1.5-1.75 INCHES/ MOVING INTO THE REGION FROM THE
SOUTH WILL CONTINUE TO LOCK IN THICK CLOUD COVER ACROSS PRACTICALLY
ALL OF THE CWA FOR THE REST OF TODAY.

PORTIONS OF THE NW MTNS WILL CONTINUE TO SEE PERIODS OF SUNSHINE
THROUGH THE REMAINDER OF THIS AFTERNOON...WITHIN THE VERY TIGHT
GRADIENT OF 925-850 MB THETA-E...AND AIDED BY LLVL DOWNSLOPING TO
THE WEST OF THE SPINE OF THE APPALACHIANS.

THE BASE OF THE THICK STRATUS/STRATOCU DECK WILL LIFT VERY LITTLE
FROM THEIR 18Z LEVELS AND CONTINUE TO SHROUD THE HIGHER RIDGE TOPS
THROUGH THIS EVENING....BEFORE GRADUALLY LOWERING DOWN THE SLOPES
SIMILAR TO LAST NIGHT.

WEAK FORCING IN THE FORM OF VERY GENTLE ISENTROPIC UPGLIDE FROM THE
SOUTH TO SSW WITHIN THE I300-310K THETA CHANNEL WILL HELP TO PRODUCE
A FEW LIGHT SHOWERS /OR MORE LIKELY AREAS OF LIGHT DRIZZLE/ THAT
WILL DRIFT NNE ACROSS THE FCST AREA THIS AFTERNOON THROUGH TONIGHT.

THE CLOUDS WILL KEEP AFTERNOON TEMPS ON THE COOL SIDE AND WELL BELOW
NORMALS ACROSS MOST OF THE AREA. JUST THOSE LUCKY FEW PLACES OVER
THE NORTHWEST MTNS COULD MEET OR EXCEED CLIMO HIGHS. MAX TEMPS WILL
BE MAINLY IN THE MID 60S...BUT SHOULD HOLD AOB 60F ACROSS SOME OF
THE EASTERN MTNS.

THIS BLANKET OF CLOUDS /AND RELATIVELY HIGH SFC DEWPOINTS...IN MID
50S TO AROUND 60F/ WILL KEEP TEMPS 10-15F ABOVE CLIMO NORMALS
OVERNIGHT.

ANY MEASURABLE RAINFALL TONIGHT WILL BE LIMITED TO SEVERAL
HUNDREDTHS OF AN INCH OR LESS.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
UPPER RIDGE WILL BE IN PLACE FROM THE OHIO VALLEY TO THE GULF COAST.
500 MB HEIGHTS WILL RISE SLIGHTLY /BY 10-20M/ DURING THE DAY
MONDAY...AS THE MEAN /AND INITIALLY SOUTHERLY/ 925-850 MB FLOW VEERS
AROUND TO THE WSW BY THE MIDDAY HOURS MONDAY.

LINGERING...EARLY MORNING LOW CLOUDS AND FOG SHOULD BE ERODED RATHER
QUICKLY BETWEEN 14-17Z MONDAY...WITH PARTLY SUNNY SKIES IN MOST
AREAS FOR THE AFTERNOON HOURS. DEEP VERTICAL MIXING OF THE WARM
/PLUS 14-15C/ AIR AT 850 MB WILL YIELD ABOVE NORMAL AFTERNOON TEMPS
IN THE MID 70S TO AROUND 80F.

SOME OF THE DEEPER VALLEYS EAST OF THE LAUREL HIGHLANDS...WHERE THE
GREATEST COMPRESSIONAL WARMING WILL OCCUR VIA AN ORTHOGONAL LLVL WSW
FLOW...COULD SOAR INTO THE LOWERS 80S IF AMPLE CLEARING OCCURS AND
SCTD SHOWERS/TSRA HOLD OFF UNTIL AFTER 20Z.

POPS FOR SCTD SHOWERS AND ISOLATED TSRA FOR MONDAY AFTERNOON WILL BE
JUST UNDER 30 PERCENT ACROSS THE NW ZONES...AND 40-45 PERCENT IN THE
SE.

WEAK LOW PRESSURE ALOFT WILL FINALLY DISAPPEAR MONDAY NIGHT AS IT
PASSES OVERHEAD. UPSTREAM CONVECTION WILL BE DROPPING ACROSS THE
GREAT LAKES AND WILL ONLY PROLONG THE CLOUDY/SHOWERY FORECAST FOR
LATE THIS PERIOD.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...


ON TUESDAY...WE SHOULD ENTER THE WARM SECTOR AHEAD OF THE STORM
LANGUISHING OVER THE PLAINS/MIDWEST/UPPER LAKES. THE WARM SECTOR
AIR WILL BE QUITE WARM FOR THE TIME OF YEAR...HAVING SPENT PLENTY
OF TIME COOKING OVER THE MS AND OH VALLEYS WITH GOOD GULF INFLOW.
TEMPS THERE RIGHT NOW ARE ABOUT 10F ABOVE AVERAGES. THEREFORE...THE
TEMPS SHOULD ROUND OUT TO 80F OR BETTER IN MANY LOCATIONS TUESDAY.
ALONG WITH THE WARM TEMPERATURES WILL BE MOIST AIR WITH DEWPOINTS
IN THE 60S. THIS WARM...MOIST AIR...ALONG WITH A WEAKENING RIDGE
WILL CREATE A GOOD SITUATION FOR SCT AFTN CONVECTION.

THE MEDIUM RANGE GUIDANCE CONTINUES TO ADVERTISE A RATHER
UNSETTLED PERIOD FOR MUCH OF THE UPCOMING WEEK.

WE ARE AND WILL REMAIN BASICALLY UNDER A MEAN UPPER RIDGE...BUT
THE PROBLEM WILL BE A WEAK FRONTAL SYSTEM THAT WILL BE MEANDERING
THROUGH CENTRAL PA FOR MUCH OF THE TIME INTO LATE WEEK. SO WHILE
THERE IS SUPPORT ALOFT FOR ORGANIZED PRECIP...THE SHOWERS WILL BE
TIED TO SMALL SCALE FEATURES THAT WILL BE HARD TO SEE MORE THAN A
DAY OR TWO DOWN THE ROAD. THE LOW LEVEL FORCING AND INCREASING
HUMIDITY/INSTABILITY WILL BRING SEVERAL CHANCES FOR MAINLY DIURNAL
SHOWERS AND THUNDERSTORMS.

THE FORECAST HAS A LOT OF REDUNDANCY IN IT...IMPLYING A PROLONGED
PERIOD OF RAIN/STORMS. THE REALITY IS LIKELY TO BE MORE LIKE A
PERIOD OF MAINLY CLOUDY SKIES BUT WITH SUNNY BREAKS DURING THE
DAY...ALONG WITH SHOWERS THAT WILL BE MOST LIKELY IN THE AFTERNOON
AND EVENING. A DIFFUSE FRONT WILL ATTEMPT TO PUSH NORTHWARD DURING
THE MIDDLE OF THE WEEK. WHERE THE FRONT WILL BE ON ANY GIVEN DAY
WILL HAVE MUCH TO DO WITH MESOSCALE INFLUENCES FROM ANY CONVECTION
THAT MANAGES TO FORM.

DESPITE AMPLE CLOUD COVER AND THE CHANCES FOR RAIN...TEMPERATURES
SHOULD REMAIN ABOVE NORMAL UNTIL AT LEAST LATE WEEK WHEN GUIDANCE
SUGGESTS WE FINALLY SEE A COLD FRONT MOVE THROUGH USHERING IN
MUCH COOLER AIR AND DRIER CONDITIONS.

&&

.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
A WAVY FRONTAL BOUNDARY JUST TO OUR SOUTH WILL SLOWLY RETURN
NORTHWARD ACROSS PENNSYLVANIA AS A WARM FRONT LATE TODAY INTO MONDAY.

WIDESPREAD IFR SOUTH /AND LOW-END MVFR CIGS CENTRAL AND NORTH/ WITH
GENERALLY 7-10SM VSBYS WILL CONTINUE THROUGH THE AFTERNOON HOURS.
LOWEST CONDITIONS WILL BE FOUND ACROSS THE SOUTHERN THIRD OF PENN.

RIDGE TOPS AOA APPROX 1900 FT MSL WILL CONTINUE TO BE SHROUDED IN
THE LOW CLOUDS/FOG THROUGH AT LEAST EARLY THIS AFTERNOON.

AREAS OF DRIZZLE AND ISOLATED TO SCATTERED -SHRA WILL BE MOVING BACK
TOWARD PA FROM THE SOUTH THIS AFTERNOON AS WELL. THE HIGHEST
PROBABILITY FOR THE LIGHT QPF WILL BE ACROSS THE SOUTHERN PA TAF
AIRFIELDS /KJST/LNS/MDT/CXY.

AFTER SOME MINOR...BRIEF IMPROVEMENT TO CIGS AND VSBYS THIS
AFTERNOON...CONDITIONS QUICKLY SLIDE DOWN TO WIDESPREAD IFR
BEGINNING LATER THIS EVE AND CONTINUING UNTIL 13-15Z MONDAY.

A RATHER UNSETTLED AND OCCASIONALLY WET PATTERN IS EXPECTED FOR
MONDAY AFTERNOON THROUGH THURSDAY...WITH DAILY CHC/S FOR CONVECTIVE
PCPN FOCUSED DURING THE AFTERNOON/EARLY EVENING /AND ASSOCD
RESTRICTIONS/.

.OUTLOOK...
MON-THU...AREAS OF EARLY MORNING IFR CONDITIONS IN STRATUS AND
FOG...TRANSITIONING TO VFR-MVFR WITH SCT PM THUNDERSTORM IMPACTS
EACH DAY.

FRI-SAT...MAINLY VFR. PATCHY MVFR TO IFR CIGS POSSIBLE 09-13Z BOTH
DAYS.

&&

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

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...DANGELO/LAMBERT
LONG TERM...LA CORTE/CERU
AVIATION...LAMBERT

000
FXUS61 KCTP 191902
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
255 PM EDT SUN MAY 19 2013

.SYNOPSIS...
HIGH PRESSURE OVER NORTHERN NEW ENGLAND AND THE MOUTH OF THE ST.
LAWRENCE LATE TODAY WILL SLIDE TO THE EAST OVERNIGHT. A DEEP
SOUTHERLY FLOW IN THE WAKE OF THIS HIGH WILL BRING INCREASING WARMTH
AND HUMIDITY TO THE REGION THROUGH THE MID-WEEK PERIOD...WITH WELL
ABOVE NORMAL AFTERNOON TEMPERATURES TUESDAY AND WEDNESDAY. SCATTERED
SHOWERS AND THUNDERSTORMS WILL OCCUR EACH AFTERNOON THROUGH THURSDAY
AS A STORM SYSTEM CURRENTLY OVER THE CENTRAL PLAINS INCHES EASTWARD.
TEMPERATURES WILL COOL BACK BELOW NORMAL WITH DRIER CONDITIONS FOR
FRIDAY AND SATURDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
A MOIST SOUTHEASTERLY FLOW NEAR THE SFC AND PLUME OF ANOMALOUSLY
HIGH PWAT AIR /1.5-1.75 INCHES/ MOVING INTO THE REGION FROM THE
SOUTH WILL CONTINUE TO LOCK IN THICK CLOUD COVER ACROSS PRACTICALLY
ALL OF THE CWA FOR THE REST OF TODAY.

PORTIONS OF THE NW MTNS WILL CONTINUE TO SEE PERIODS OF SUNSHINE
THROUGH THE REMAINDER OF THIS AFTERNOON...WITHIN THE VERY TIGHT
GRADIENT OF 925-850 MB THETA-E...AND AIDED BY LLVL DOWNSLOPING TO
THE WEST OF THE SPINE OF THE APPALACHIANS.

THE BASE OF THE THICK STRATUS/STRATOCU DECK WILL LIFT VERY LITTLE
FROM THEIR 18Z LEVELS AND CONTINUE TO SHROUD THE HIGHER RIDGE TOPS
THROUGH THIS EVENING....BEFORE GRADUALLY LOWERING DOWN THE SLOPES
SIMILAR TO LAST NIGHT.

WEAK FORCING IN THE FORM OF VERY GENTLE ISENTROPIC UPGLIDE FROM THE
SOUTH TO SSW WITHIN THE I300-310K THETA CHANNEL WILL HELP TO PRODUCE
A FEW LIGHT SHOWERS /OR MORE LIKELY AREAS OF LIGHT DRIZZLE/ THAT
WILL DRIFT NNE ACROSS THE FCST AREA THIS AFTERNOON THROUGH TONIGHT.

THE CLOUDS WILL KEEP AFTERNOON TEMPS ON THE COOL SIDE AND WELL BELOW
NORMALS ACROSS MOST OF THE AREA. JUST THOSE LUCKY FEW PLACES OVER
THE NORTHWEST MTNS COULD MEET OR EXCEED CLIMO HIGHS. MAX TEMPS WILL
BE MAINLY IN THE MID 60S...BUT SHOULD HOLD AOB 60F ACROSS SOME OF
THE EASTERN MTNS.

THIS BLANKET OF CLOUDS /AND RELATIVELY HIGH SFC DEWPOINTS...IN MID
50S TO AROUND 60F/ WILL KEEP TEMPS 10-15F ABOVE CLIMO NORMALS
OVERNIGHT.

ANY MEASURABLE RAINFALL TONIGHT WILL BE LIMITED TO SEVERAL
HUNDREDTHS OF AN INCH OR LESS.

&&

.SHORT TERM /MONDAY/...
UPPER RIDGE WILL BE IN PLACE FROM THE OHIO VALLEY TO THE GULF COAST.
500 MB HEIGHTS WILL RISE SLIGHTLY /BY 10-20M/ DURING THE DAY
MONDAY...AS THE MEAN /AND INITIALLY SOUTHERLY/ 925-850 MB FLOW VEERS
AROUND TO THE WSW BY THE MIDDAY HOURS MONDAY.

LINGERING...EARLY MORNING LOW CLOUDS AND FOG SHOULD BE ERODED RATHER
QUICKLY BETWEEN 14-17Z MONDAY...WITH PARTLY SUNNY SKIES IN MOST
AREAS FOR THE AFTERNOON HOURS. DEEP VERTICAL MIXING OF THE WARM
/PLUS 14-15C/ AIR AT 850 MB WILL YIELD ABOVE NORMAL AFTERNOON TEMPS
IN THE MID 70S TO AROUND 80F.

SOME OF THE DEEPER VALLEYS EAST OF THE LAUREL HIGHLANDS...WHERE THE
GREATEST COMPRESSIONAL WARMING WILL OCCUR VIA AN ORTHOGONAL LLVL WSW
FLOW...COULD SOAR INTO THE LOWERS 80S IF AMPLE CLEARING OCCURS AND
SCTD SHOWERS/TSRA HOLD OFF UNTIL AFTER 20Z.

POPS FOR SCTD SHOWERS AND ISOLATED TSRA FOR MONDAY AFTERNOON WILL BE
JUST UNDER 30 PERCENT ACROSS THE NW ZONES...AND 40-45 PERCENT IN THE
SE.

&&

.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
WEAK LOW PRESSURE ALOFT WILL FINALLY DISAPPEAR MONDAY NIGHT AS IT
PASSES OVERHEAD. UPSTREAM CONVECTION WILL BE DROPPING ACROSS THE
GREAT LAKES AND WILL ONLY PROLONG THE CLOUDY/SHOWERY FORECAST FOR
LATE THIS PERIOD.

ON TUESDAY...WE SHOULD ENTER THE WARM SECTOR AHEAD OF THE STORM
LANGUISHING OVER THE PLAINS/MIDWEST/UPPER LAKES. THE WARM SECTOR
AIR WILL BE QUITE WARM FOR THE TIME OF YEAR...HAVING SPENT PLENTY
OF TIME COOKING OVER THE MS AND OH VALLEYS WITH GOOD GULF INFLOW.
TEMPS THERE RIGHT NOW ARE ABOUT 10F ABOVE AVERAGES. THEREFORE...THE
TEMPS SHOULD ROUND OUT TO 80F OR BETTER IN MANY LOCATIONS TUES.
BUT SCT AFTN CONVECTION IS THEN POSSIBLE.

THE MEDIUM RANGE GUIDANCE CONTINUES TO ADVERTISE A RATHER
UNSETTLED PERIOD OF TIME FOR MUCH OF THE UPCOMING WEEK.

WE ARE AND WILL REMAIN BASICALLY UNDER A MEAN UPPER RIDGE...BUT
THE PROBLEM WILL BE A WEAK FRONTAL SYSTEM THAT WILL BE MEANDERING
AROUND CENTRAL PA FOR MUCH OF THE TIME INTO LATE WEEK. SO WHILE
THERE IS SUPPORT ALOFT FOR ORGANIZED PRECIP...THE SHOWERS WILL BE
TIED TO SMALL SCALE FEATURES THAT WILL BE HARD TO SEE MORE THAN A
DAY OR TWO DOWN THE ROAD. THE LOW LEVEL FORCING AND INCREASING
HUMIDITY/INSTABILITY WILL BRING SEVERAL CHANCES FOR MAINLY DIURNAL
SHOWERS AND THUNDERSTORMS.

THE FORECAST HAS A LOT OF REDUNDANCY IN IT...IMPLYING A PROLONGED
PERIOD OF RAIN/STORMS. THE REALITY IS LIKELY TO BE MORE LIKE A
PERIOD OF MAINLY CLOUDY SKIES BUT WITH SUNNY BREAKS DURING THE
DAY...ALONG WITH SHOWERS THAT WILL BE MOST LIKELY IN THE AFTERNOON
AND EVENING. A DIFFUSE FRONT WILL ATTEMPT TO PUSH NORTHWARD DURING
THE MIDDLE OF THE WEEK. WHERE THE FRONT WILL BE ON ANY GIVEN DAY
WILL HAVE MUCH TO DO WITH MESOSCALE INFLUENCES FROM ANY CONVECTION
THAT MANAGES TO FORM.

DESPITE AMPLE CLOUD COVER AND THE CHANCES FOR RAIN...TEMPERATURES
SHOULD REMAIN ABOVE NORMAL UNTIL AT LEAST LATE WEEK WHEN GUIDANCE
SUGGESTS WE FINALLY SEE A COLD FRONT MOVE THROUGH USHERING IN
MUCH COOLER AIR AND DRIER CONDITIONS.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
A WAVY FRONTAL BOUNDARY JUST TO OUR SOUTH WILL SLOWLY RETURN
NORTHWARD ACROSS PENNSYLVANIA AS A WARM FRONT LATE TODAY INTO MONDAY.

WIDESPREAD IFR SOUTH /AND LOW-END MVFR CIGS CENTRAL AND NORTH/ WITH
GENERALLY 7-10SM VSBYS WILL CONTINUE THROUGH THE AFTERNOON HOURS.
LOWEST CONDITIONS WILL BE FOUND ACROSS THE SOUTHERN THIRD OF PENN.

RIDGE TOPS AOA APPROX 1900 FT MSL WILL CONTINUE TO BE SHROUDED IN
THE LOW CLOUDS/FOG THROUGH AT LEAST EARLY THIS AFTERNOON.

AREAS OF DRIZZLE AND ISOLATED TO SCATTERED -SHRA WILL BE MOVING BACK
TOWARD PA FROM THE SOUTH THIS AFTERNOON AS WELL. THE HIGHEST
PROBABILITY FOR THE LIGHT QPF WILL BE ACROSS THE SOUTHERN PA TAF
AIRFIELDS /KJST/LNS/MDT/CXY.

AFTER SOME MINOR...BRIEF IMPROVEMENT TO CIGS AND VSBYS THIS
AFTERNOON...CONDITIONS QUICKLY SLIDE DOWN TO WIDESPREAD IFR
BEGINNING LATER THIS EVE AND CONTINUING UNTIL 13-15Z MONDAY.

A RATHER UNSETTLED AND OCCASIONALLY WET PATTERN IS EXPECTED FOR
MONDAY AFTERNOON THROUGH THURSDAY...WITH DAILY CHC/S FOR CONVECTIVE
PCPN FOCUSED DURING THE AFTERNOON/EARLY EVENING /AND ASSOCD
RESTRICTIONS/.

.OUTLOOK...
MON-THU...AREAS OF EARLY MORNING IFR CONDITIONS IN STRATUS AND
FOG...TRANSITIONING TO VFR-MVFR WITH SCT PM THUNDERSTORM IMPACTS
EACH DAY.

FRI-SAT...MAINLY VFR. PATCHY MVFR TO IFR CIGS POSSIBLE 09-13Z BOTH
DAYS.


&&

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

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LA CORTE/STEINBUGL
AVIATION...LAMBERT

000
FXUS61 KCTP 191643
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1223 PM EDT SUN MAY 19 2013

.SYNOPSIS...
HIGH PRESSURE OVER THE NORTHEASTERN STATES WILL SLIDE OFF THE COAST
THIS AFTERNOON. A PROLONGED STRETCH OF UNSETTLED WEATHER IS IN
STORE OVER THE NEXT SEVERAL DAYS AS A STORM SYSTEM CURRENTLY OVER
THE CENTRAL PLAINS INCHES EASTWARD. TEMPERATURES TODAY WILL
GRADUALLY RISE THROUGH THE FIRST PART OF THE WEEK...BUT WILL COOL
BACK BELOW NORMAL BY NEXT WEEKEND.

&&

.NEAR TERM /UNTIL 8 PM THIS EVENING/...
A MOIST SOUTHEASTERLY FLOW NEAR THE SFC AND PLUME OF ANOMALOUSLY
HIGH PWAT AIR /1.5-1.75 INCHES/ MOVING INTO THE REGION FROM THE
SOUTH WILL CONTINUE TO LOCK IN THICK CLOUD COVER ACROSS PRACTICALLY
ALL OF THE CWA FOR THE REST OF TODAY.

PORTIONS OF THE NW MTNS WILL CONTINUE TO SEE PERIODS OF SUNSHINE
THROUGH THIS AFTERNOON...SINCE THE DEPTH OF THE MOISTURE IS THE MOST
SHALLOW THERE...AND LLVL DOWNSLOPING TO THE WEST OF THE SPINE OF THE
APPALACHIANS WILL OCCUR.

THE BASE OF THE THICK STRATUS/STRATOCU DECK WILL BE DRAPED OVER THE
HIGHER RIDGE TOPS. HOWEVER...THE STRONG...LATE MAY SUN WILL WARM
THE BLYR A FEW...TO SVRL DEG F MORE AND LIFT THE BASE OF THE DECK UP
ANOTHER 200-500 FT FROM THEIR 16Z LEVELS.

WEAK FORCING IN THE FORM OF VERY GENTLE ISENTROPIC UPGLIDE FROM THE
SOUTH TO SSW WITHIN THE I300-310K THETA CHANNEL WILL HELP TO PRODUCE
A FEW LIGHT SHOWERS /OR MORE LIKELY AREAS OF DRIZZLE/ THAT WILL
DRIFT NNE ACROSS THE FCST AREA THIS AFTERNOON INTO THIS EVENING.

THE CLOUDS WILL KEEP TEMPS ON THE COOL SIDE AND WELL BELOW NORMALS
ACROSS MOST OF THE AREA. JUST THOSE LUCKY FEW PLACES OVER THE
NORTHWEST MTNS COULD MEET OR EXCEED CLIMO HIGHS. MAX TEMPS WILL BE
MAINLY IN THE MID 60S...BUT SHOULD HOLD AOB 60F ACROSS SOME OF THE
EASTERN MTNS.

&&

.SHORT TERM /8 PM THIS EVENING THROUGH TUESDAY/...
A MINOR UPPER RIDGE IS GENERALLY IN PLACE FROM THE UPPER GREAT
LAKES TO THE GULF COAST. HOWEVER...THE OLD MID-LEVEL LOW IS STILL
SEEN IN MDL INITIALIZATIONS OVER THE OHIO VALLEY. THIS FEATURE AND
THE DEAD/DIFFUSE FRONT TO OUR SOUTH WILL CONTINUE TO GENERATE
SHOWERS ALL ACROSS THE MID-ATLANTIC FOR THE NEXT TWO DAYS UNTIL
THE LOW FINALLY DISAPPEARS SOMETIME AROUND MONDAY NIGHT AS IT
PASSES OVERHEAD. UPSTREAM CONVECTION WILL BE DROPPING ACROSS THE
GREAT LAKES AND WILL ONLY PROLONG THE CLOUDY/SHOWERY FORECAST FOR
LATE THIS PERIOD.

ON TUESDAY...WE SHOULD ENTER THE WARM SECTOR AHEAD OF THE STORM
LANGUISHING OVER THE PLAINS/MIDWEST/UPPER LAKES. THE WARM SECTOR
AIR WILL BE QUITE WARM FOR THE TIME OF YEAR...HAVING SPENT PLENTY
OF TIME COOKING OVER THE MS AND OH VALLEYS WITH GOOD GULF INFLOW.
TEMPS THERE RIGHT NOW ARE ABOUT 10F ABOVE AVERAGES. THEREFORE...THE
TEMPS SHOULD ROUND OUT TO 80F OR BETTER IN MANY LOCATIONS TUES.
BUT SCT AFTN CONVECTION IS THEN POSSIBLE.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
THE MEDIUM RANGE GUIDANCE CONTINUES TO ADVERTISE A RATHER
UNSETTLED PERIOD OF TIME FOR MUCH OF THE UPCOMING WEEK.

WE ARE AND WILL REMAIN BASICALLY UNDER A MEAN UPPER RIDGE...BUT
THE PROBLEM WILL BE A WEAK FRONTAL SYSTEM THAT WILL BE MEANDERING
AROUND CENTRAL PA FOR MUCH OF THE TIME INTO LATE WEEK. SO WHILE
THERE IS SUPPORT ALOFT FOR ORGANIZED PRECIP...THE SHOWERS WILL BE
TIED TO SMALL SCALE FEATURES THAT WILL BE HARD TO SEE MORE THAN A
DAY OR TWO DOWN THE ROAD. THE LOW LEVEL FORCING AND INCREASING
HUMIDITY/INSTABILITY WILL BRING SEVERAL CHANCES FOR MAINLY DIURNAL
SHOWERS AND THUNDERSTORMS.

THE FORECAST HAS A LOT OF REDUNDANCY IN IT...IMPLYING A PROLONGED
PERIOD OF RAIN/STORMS. THE REALITY IS LIKELY TO BE MORE LIKE A
PERIOD OF MAINLY CLOUDY SKIES BUT WITH SUNNY BREAKS DURING THE
DAY...ALONG WITH SHOWERS THAT WILL BE MOST LIKELY IN THE AFTERNOON
AND EVENING. A DIFFUSE FRONT WILL ATTEMPT TO PUSH NORTHWARD DURING
THE MIDDLE OF THE WEEK. WHERE THE FRONT WILL BE ON ANY GIVEN DAY
WILL HAVE MUCH TO DO WITH MESOSCALE INFLUENCES FROM ANY CONVECTION
THAT MANAGES TO FORM.

DESPITE AMPLE CLOUD COVER AND THE CHANCES FOR RAIN...TEMPERATURES
SHOULD REMAIN ABOVE NORMAL UNTIL AT LEAST LATE WEEK WHEN GUIDANCE
SUGGESTS WE FINALLY SEE A COLD FRONT MOVE THROUGH USHERING IN
MUCH COOLER AIR AND DRIER CONDITIONS.

&&

.AVIATION /16Z SUNDAY THROUGH THURSDAY/...
A WAVY FRONTAL BOUNDARY JUST TO OUR SOUTH WILL SLOWLY RETURN
NORTHWARD ACROSS PENNSYLVANIA AS A WARM FRONT LATE TODAY INTO MONDAY.

WIDESPREAD IFR /TO LOW END MVFR CIGS/ WITH GENERALLY 7-10SM VSBYS
WILL CONTINUE THROUGH THE AFTERNOON HOURS. LOWEST CONDITIONS WILL BE
FOUND ACROSS THE SOUTHERN THIRD OF PENN.

RIDGE TOPS AOA APPROX 1900 FT MSL WILL CONTINUE TO BE SHROUDED IN
THE LOW CLOUDS/FOG THROUGH AT LEAST EARLY THIS AFTERNOON.

AREAS OF DRIZZLE AND SOME SHRA WILL BE MOVING BACK TOWARD PA FROM
THE SOUTH THIS AFTERNOON AS WELL. THE HIGHEST PROBABILITY FOR THE
LIGHT QPF WILL BE ACROSS THE SOUTHERN PA TAF AIRFIELDS
/KJST/LNS/MDT/CXY.

AFTER SOME MINOR...BRIEF IMPROVEMENT TO CIGS AND VSBYS THIS
AFTERNOON...WIDESPREAD IFR RETURNS FOR LATER THIS EVE INTO MONDAY AS
THE AFOREMENTIONED WARM FRONTAL BOUNDARY LIFTS SLOWLY NORTHWARD.

A RATHER UNSETTLED AND POTENTIALLY WET PATTERN IS EXPECTED DURING
THE MIDDLE TO SECOND HALF OF UPCOMING WEEK...WITH DAILY CHC/S FOR
CONVECTIVE PCPN AND ASSOCD RESTRICTIONS.

.OUTLOOK...
MON...MVFR-IFR CIGS.
TUE-THU...VFR-MVFR WITH SCT PM THUNDERSTORM IMPACTS.

&&

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

&&

$$
SYNOPSIS...DANGELO/LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...DANGELO/LAMBERT
LONG TERM...LA CORTE/STEINBUGL
AVIATION...LAMBERT

000
FXUS61 KCTP 191352
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
931 AM EDT SUN MAY 19 2013

.SYNOPSIS...
HIGH PRESSURE OVER THE NORTHEASTERN STATES WILL SLIDE OFF THE
COAST TODAY. A PROLONGED STRETCH OF UNSETTLED WEATHER IS IN STORE
OVER THE NEXT SEVERAL DAYS AS A STORM SYSTEM CURRENTLY OVER THE
CENTRAL PLAINS INCHES EASTWARD. TEMPERATURES TODAY WILL GRADUALLY
RISE THROUGH THE FIRST PART OF THE WEEK...BUT WILL COOL BACK BELOW
NORMAL BY NEXT WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
STAYING SOMEWHAT IN TUNE WITH MY COLLEAGUES PREVIOUS DESCRIPTION OF
THE THICK CLOUD COVER USING NEIL SEDAKA`S EARLY 1960S /THEN 1975/
POP SONG - BREAKING UP IS HARD TO DO /WITH SUCH A PERSISTENT SERLY
FLOW/...I AGREE WITH HIS ASSESSMENT - WE NEVER CAN SAY GOODBYE.

WE CERTAINLY DON`T WANT TO STRING ANYONE ALONG...WITHOUT ANY RHYME
OR REASON...BY SUGGESTING THAT THE ATMOSPHERE CAN ORCHESTRATE ANY
APPRECIABLE CLEARING ACROSS CENTRAL PA TODAY. IN FACT...DEEP LAYER
MOISTURE WILL CONTINUE TO INCREASE ACROSS THE COMMONWEALTH INTO
TONIGHT WITH THE NOSE OF A NORTH/SOUTH AXIS OF ANOMALOUSLY HIGH PWAT
AIR /1.5-1.75 INCHES/ MOVING INTO THE REGION...LOCKING IN THE THICK
CLOUD COVER.

PORTIONS OF THE NW MTNS HAVE ALREADY BROKEN OUT INTO SOME CLEARING
AND WILL CONTINUE TO SEE PERIODS OF - SUNSHINE ON MY SHOULDERS -
THROUGH THIS AFTERNOON...SINCE THE DEPTH OF THE MOISTURE IS THE MOST
SHALLOW THERE...AND LLVL DOWNSLOPING TO THE WEST OF THE SPINE OF THE
APPALACHIANS WILL OCCUR.

THE BASE OF THE THICK STRATUS/STRATOCU DECK WILL BE DRAPED OVER THE
RIDGE TOPS INTO THE MIDDAY HOURS. THE STRONG MAY SUN COULD LIFT THE
BASE OF THE DECK UP A LITTLE...BUT HOLES IN THE CLOUDS WILL BE TOUGH
TO FIND. THE CLOUDS ARE MADE OF MARITIME AIR WHICH CONTAINS LOTS OF
FINE DROPLETS WHICH ARE ALWAYS GOOD FOR PRODUCING AREAS OF LIGHT
DRIZZLE. FORCING IS ALMOST NON EXISTENT ABOVE THE LOWEST 5KFT OF THE
ATMOSPHERE TODAY. THE CLOUDS WILL AGAIN KEEP TEMPS DOWN BELOW
NORMALS ACROSS MOST OF THE AREA. JUST THOSE LUCKY FEW PLACES IN THE
WEST COULD MEET OR EXCEED CLIMO HIGHS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
A MINOR UPPER RIDGE IS GENERALLY IN PLACE FROM THE UPPER GREAT
LAKES TO THE GULF COAST. HOWEVER...THE OLD MID-LEVEL LOW IS STILL
SEEN IN MDL INITIALIZATIONS OVER THE OHIO VALLEY. THIS FEATURE AND
THE DEAD/DIFFUSE FRONT TO OUR SOUTH WILL CONTINUE TO GENERATE
SHOWERS ALL ACROSS THE MID-ATLANTIC FOR THE NEXT TWO DAYS UNTIL
THE LOW FINALLY DISAPPEARS SOMETIME AROUND MONDAY NIGHT AS IT
PASSES OVERHEAD. UPSTREAM CONVECTION WILL BE DROPPING ACROSS THE
GREAT LAKES AND WILL ONLY PROLONG THE CLOUDY/SHOWERY FORECAST FOR
LATE THIS PERIOD.

ON TUESDAY...WE SHOULD ENTER THE WARM SECTOR AHEAD OF THE STORM
LANGUISHING OVER THE PLAINS/MIDWEST/UPPER LAKES. THE WARM SECTOR
AIR WILL BE QUITE WARM FOR THE TIME OF YEAR...HAVING SPENT PLENTY
OF TIME COOKING OVER THE MS AND OH VALLEYS WITH GOOD GULF INFLOW.
TEMPS THERE RIGHT NOW ARE ABOUT 10F ABOVE AVERAGES. THEREFORE...THE
TEMPS SHOULD ROUND OUT TO 80F OR BETTER IN MANY LOCATIONS TUES.
BUT SCT AFTN CONVECTION IS THEN POSSIBLE.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
THE MEDIUM RANGE GUIDANCE CONTINUES TO ADVERTISE A RATHER
UNSETTLED PERIOD OF TIME FOR MUCH OF THE UPCOMING WEEK.

WE ARE AND WILL REMAIN BASICALLY UNDER A MEAN UPPER RIDGE...BUT
THE PROBLEM WILL BE A WEAK FRONTAL SYSTEM THAT WILL BE MEANDERING
AROUND CENTRAL PA FOR MUCH OF THE TIME INTO LATE WEEK. SO WHILE
THERE IS SUPPORT ALOFT FOR ORGANIZED PRECIP...THE SHOWERS WILL BE
TIED TO SMALL SCALE FEATURES THAT WILL BE HARD TO SEE MORE THAN A
DAY OR TWO DOWN THE ROAD. THE LOW LEVEL FORCING AND INCREASING
HUMIDITY/INSTABILITY WILL BRING SEVERAL CHANCES FOR MAINLY DIURNAL
SHOWERS AND THUNDERSTORMS.

THE FORECAST HAS A LOT OF REDUNDANCY IN IT...IMPLYING A PROLONGED
PERIOD OF RAIN/STORMS. THE REALITY IS LIKELY TO BE MORE LIKE A
PERIOD OF MAINLY CLOUDY SKIES BUT WITH SUNNY BREAKS DURING THE
DAY...ALONG WITH SHOWERS THAT WILL BE MOST LIKELY IN THE AFTERNOON
AND EVENING. A DIFFUSE FRONT WILL ATTEMPT TO PUSH NORTHWARD DURING
THE MIDDLE OF THE WEEK. WHERE THE FRONT WILL BE ON ANY GIVEN DAY
WILL HAVE MUCH TO DO WITH MESOSCALE INFLUENCES FROM ANY CONVECTION
THAT MANAGES TO FORM.

DESPITE AMPLE CLOUD COVER AND THE CHANCES FOR RAIN...TEMPERATURES
SHOULD REMAIN ABOVE NORMAL UNTIL AT LEAST LATE WEEK WHEN GUIDANCE
SUGGESTS WE FINALLY SEE A COLD FRONT MOVE THROUGH USHERING IN
MUCH COOLER AIR AND DRIER CONDITIONS.

&&

.AVIATION /13Z SUNDAY THROUGH THURSDAY/...
A WAVY FRONTAL BOUNDARY JUST TO OUR SOUTH WILL SLOWLY RETURN
NORTHWARD ACROSS PENNSYLVANIA AS A WARM FRONT LATE TODAY INTO MONDAY.

WIDESPREAD IFR /TO VERY LOW END MVFR CIGS/ WILL CONTINUE THROUGH AT
LEAST 17Z TODAY BEFORE LIFTING TO LOW-MID RANGE MVFR DURING THE MID
TO LATE AFTERNOON HOURS THANKS TO SEVERAL DEG F OF BOUNDARY LAYER
WARMING.

RIDGE TOPS AOA APPROX 1900 FT MSL WILL CONTINUE TO BE SHROUDED IN
THE LOW CLOUDS/FOG THROUGH AT LEAST EARLY THIS AFTERNOON.

AREAS OF DRIZZLE AND SOME SHRA WILL BE MOVING BACK TOWARD PA FROM
THE SOUTH THIS AFTERNOON AS WELL. THE HIGHEST PROBABILITY FOR THE
LIGHT QPF WILL BE ACROSS THE SOUTHERN PA TAF AIRFIELDS
/KJST/LNS/MDT/CXY.

AFTER SOME MINOR...BRIEF IMPROVEMENT TO CIGS AND VSBYS THIS
AFTERNOON...WIDESPREAD IFR RETURNS FOR LATER THIS EVE INTO MONDAY AS
THE AFOREMENTIONED WARM FRONTAL BOUNDARY LIFTS SLOWLY NORTHWARD.

A RATHER UNSETTLED AND POTENTIALLY WET PATTERN IS EXPECTED DURING
THE MIDDLE TO SECOND HALF OF UPCOMING WEEK...WITH DAILY CHC/S FOR
CONVECTIVE PCPN AND ASSOCD RESTRICTIONS.

.OUTLOOK...
MON...MVFR-IFR CIGS.
TUE-THU...VFR-MVFR WITH SCT PM THUNDERSTORM IMPACTS.

&&

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

&&

$$
SYNOPSIS...DANGELO
NEAR TERM...LAMBERT/DANGELO
SHORT TERM...DANGELO
LONG TERM...LA CORTE/STEINBUGL
AVIATION...LAMBERT