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000
FXUS61 KPHI 181946
AFDPHI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
346 PM EDT TUE JUN 18 2013
.SYNOPSIS...
A COLD FRONT WILL MOVE OFF THE COAST TONIGHT AS WEAK LOW PRESSURE
MOVES ALONG IT. HIGH PRESSURE FROM THE GREAT LAKES REGION WILL THEN
BUILD INTO THE NORTHEAST AND MID-ATLANTIC TOMORROW. THE CENTER OF
THIS HIGH WILL SHIFT OFFSHORE ON THURSDAY. A REINFORCING SHOT OF
CANADIAN HIGH PRESSURE MOVES TOWARD THE REGION ON FRIDAY...THEN OFF
THE COAST ON SATURDAY. A RETURN FLOW AROUND THIS HIGH WILL BRING AN
INCREASE IN HEAT AND HUMIDITY AND A THREAT OF SCATTERED SHOWERS AND
THUNDERSTORMS THIS WEEKEND AND INTO EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
VERY TROPICAL-ISH AIRMASS IN PLACE THIS EVENING AND TONIGHT AS A
WEAK FRONTAL BOUNDARY SAGS ACROSS THE MID-ATLANTIC STATES. THERE IS
AMPLE ELEVATED INSTABILITY AROUND THE REGION TO MAINTAIN THE
CURRENT SHOWER/THUNDERSTORM ACTIVITY EAST ACROSS OUR REGION. WITH
THE WEAKENED FLOW ALOFT ANY MORE STORMS THAT INITIATE WILL MOVE VERY
SLOWLY AND INUNDATE THE AREAS THEY PASS OVER. WE HAD SEVERAL FLASH
FLOOD WARNINGS ISSUED THIS AFTERNOON AND SAW HOURLY RAINFALL RATES
EXCEED 1.5+ INCHES FROM EASTERN PENNSYLVANIA INTO SOUTHERN NEW
JERSEY.
EVERYTHING WILL BE SLIDING OFFSHORE OVER THE NEXT COUPLE OF HOURS
THOUGH THE COLD FRONT TO OUR NORTH MAY TOUCH OFF EVEN MORE WIDELY
SCATTERED SHOWERS. COULD NOT REMOVE ALL CHANCES THROUGH THE EVENING
HOURS AS SOME OF THE HI-RES MODELS SHOW THESE SHOWERS TRAVERSING THE
REGION. NOT EXPECTING THE TORRENTIAL DOWNPOURS AND CONVECTION TO BE
AN ISSUE AS HEATING TO OUR NORTH AND WEST HAS BEEN WEAKENED WITH THE
EXTENSIVE MID AND HIGHER LEVEL CLOUDS. THE CU FIELD WELL TO OUR
NORTHWEST IS REALLY FLAT LOOKING AS DEWPOINTS BEHIND THE FRONT ARE
IN THE MID TO UPPER-50S. THE FRONT COULD HOWEVER POSE AN ISSUE IN
TERMS OF FOG/STRATUS FORMATION LATE TONIGHT. DEPENDING ON HOW FAST
IT SLIDES THROUGH AND WE GET THE DRIER DEWPOINTS MIGHT ALLOW A
WIDESPREAD FOG TO FORM UNDER A BUILDING INVERSION (NEAR THE FRONT)
AND WITH THE ADDED MOISTURE FROM TODAYS RAIN. DO NOT THINK IT WILL
DENSE ENOUGH TO HAVE TO WORRY ABOUT HEADLINES, BUT IT COULD BECOME
THICK IN SOME SPOTS.
OVERNIGHT LOWS WERE A STRAIGHT BLEND OF THE MET/MAV.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
THE COLD FRONT WILL CONTINUE TO PUSH FURTHER SOUTH AND EAST AND THE
DRYING NORTHERLY FLOW BEHIND THE FRONT INCREASES. MID-LEVEL AND
SURFACE RIDGING START TO RE-ENTER THE REGION FROM THE
WEST-NORTHWEST WHICH HELPS TO KEEP OUR REGION DRY FOR THE MOST
PART. CONTINUE WITH SOME SLIGHT CHANCE POPS ACROSS THE EXTREME
SOUTHERN DELMARVA WHERE SOME LOW-LEVEL CONVERGENCE ALONG THE FRONT
MAY STILL EXIST AND WHERE DEWPOINTS WILL CONTINUE TO POOL IN THE
UPPER-60S. TEMPERATURES WILL BE A COUPLE DEGREES COOLER TOMORROW
BEHIND THE FRONT AND A BASIC BLEND OF THE MET/MAV WAS USED FOR HIGHS.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
SURFACE HIGH PRESSURE IS EXPECTED TO BUILD OVER THE REGION WEDNESDAY
NIGHT...WITH THE CENTER OF THE HIGH MOVING OFF THE COAST ON
THURSDAY. A REINFORCING SHOT OF CANADIAN HIGH PRESSURE MOVES TOWARD
THE REGION ON FRIDAY...THEN OFF THE COAST ON SATURDAY. THIS HIGH
SHOULD THEN INFLUENCE WEATHER OVER THE AREA INTO NEXT WEEK AS A
SOUTHWEST FLOW ON ITS WESTERN SIDE BRINGS IN WARM AND HUMID AIR.
A CHANCE OF SHOWERS OR THUNDERSTORMS ARE POSSIBLE JUST ABOUT
EVERYDAY FROM SUNDAY INTO EARLY NEXT WEEK...BUT MOST OF THE TIME
SHOULD BE RAIN FREE. THIS LOOKS MORE LIKE A TYPICAL SUMMER TIME
PATTERN IN THE MID PORTIONS OF THE ATMOSPHERE AS A RIDGE TRIES TO
BUILD EAST FROM THE HIGH PLAINS. TEMPERATURES WILL START OFF IN THE
NORMAL RANGE....THEN CLIMB ABOVE NORMAL LATE IN THE WEEKEND AND
EARLY NEXT WEEK.
&&
.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
THIS EVENING...VERY COMPLEX FORECAST WITH MOSTLY VFR EXPECTED.
NUMEROUS SHOWERS AND THUNDERSTORMS WILL CONTINUE TO PLAGUE OUR
TERMINALS OVER THE NEXT COUPLE OF HOURS AS A WAVE OF LOW PRESSURE
MOVES THROUGH. THE HEAVIER SHOWERS AND THUNDERSTORMS WILL CAUSE
LOCAL IFR CONDITIONS WINDS WILL PREDOMINANTLY BE OUT OF THE
EAST-SOUTHEAST AND REMAIN LIGHT FOR THIS AFTERNOON. MULTIPLE OUTFLOW
BOUNDARIES AND HEAVIER SHOWERS WILL CAUSE TEMPORARY GUSTS WITH
VARIABLE DIRECTIONS.
TONIGHT...WEAK COLD FRONT TO THE NORTHWEST WILL SLOWLY DRAG ITSELF
TOWARDS THE REGION TONIGHT AND TRIES TO PUSH THROUGH. WINDS SHOULD
BACK TOWARDS THE SOUTHWEST AND THEN NORTH BEHIND THE FRONT. IF THE
FRONT SLOWS EVEN FURTHER OR STALLS JUST TO THE NORTH WE COULD HAVE
ISSUES WITH STRATUS AND FOG THROUGH THE MORNING HOURS....IFR/MVFR
POSSIBLE.
WEDNESDAY...VFR WITH SCATTERED CIGS. WILL MAINTAIN A NORTHERLY WIND
BEHIND THE FRONT AROUND 10KTS.
OUTLOOK...
WEDNESDAY NIGHT THROUGH SUNDAY...VFR EXCEPT IN MORNING FOG/HAZE OR
MAINLY AFTERNOON AND EVENING SHOWERS/THUNDERSTORMS.
&&
.MARINE...
SUB-ADVISORY CONDITIONS LOOK TO PERSIST ACROSS OUR WATERS TONIGHT
AND TOMORROW. A WEAK COLD FRONT WILL MOVE THROUGH LATE TONIGHT INTO
WEDNESDAY MORNING AS HIGH PRESSURE SINKS TOWARDS THE SOUTH. WINDS
WILL START OFF EASTERLY AND THEN TURN NORTHERLY BEHIND THE FRONT
TOMORROW. THE PRESSURE GRADIENT MAY BECOME TIGHT FOR A PERIOD
TOMORROW AFTERNOON AND COULD PRODUCE SOME MARGINAL SMALL CRAFT GUSTS
BUT DID NOT HAVE THE CONFIDENCE OR LONGEVITY OF THE EVENT TO PUT UP
A FLAG. SEAS WILL CLIMB UPWARDS OF 4 FEET THROUGH TOMORROW AS
CONDITIONS BECOME MORE TRANQUIL LATER IN THE DAY.
OUTLOOK... NO HEADLINES ARE EXPECTED THROUGH SUNDAY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MIKETTA
NEAR TERM...HEAVENER
SHORT TERM...HEAVENER
LONG TERM...MIKETTA
AVIATION...HEAVENER
MARINE...HEAVENER
000
FXUS61 KPHI 181347
AFDPHI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
947 AM EDT TUE JUN 18 2013
.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH THE FORECAST AREA TODAY AND TONIGHT
WITH WEAK LOW PRESSURE FORMING ALONG IT. A HIGH PRESSURE SYSTEM WILL
THEN BUILD INTO THE NORTHEAST AND MID-ATLANTIC TOMORROW. THE CENTER
OF THE HIGH WILL SHIFT OFFSHORE ON THURSDAY AND REMAIN IN PLACE
THROUGH THE WEEKEND. A RETURN FLOW AROUND THE HIGH WILL BRING AN
INCREASE IN HEAT AND HUMIDITY AND A THREAT OF SCATTERED SHOWERS AND
THUNDERSTORMS THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
GRIDS ARE IN GOOD SHAPE THOUGH THERE IS A BIT MORE STRATUS
ADVECTING INTO THE REGION THAN ORIGINALLY THOUGHT. THE 12Z KIAD
SOUNDING SHOWS A WEAK INVERSION AROUND 400FT WITH DRIER AIR ABOVE
IT WHILE KWAL SHOWS A MORE MOIST DOUBLE INVERSION. THE FIRST ONE
IS SET UP AROUND 300FT AND THE SECOND IS AROUND 1500FT WHICH IS
HELPING TO KEEP THE LOW-LEVEL MOISTURE TRAPPED AS IT SLOWLY
SPREADS OUT. THE MAIN AREAS OF STRATUS THIS MORNING ARE FROM
NORTHERN DELMARVA EAST INTO SOUTHERN NEW JERSEY AND THEN SOUTH IN
THE VIRGINIA TIDEWATER REGION. ONCE WE WARM INTO THE MID-70S THIS
INVERSION SHOULD BREAK AND THE LOW DECK SHOULD LIFT OR BEGIN TO
SCATTER OUT A BIT.
WE WILL CONTINUE TO SEE SCATTERED SHOWERS AND THUNDERSTORMS FORM
DURING A BETTER PART OF THE DAY AS MORE MOISTURE SURGES INTO THE
COLUMN. PWATS WILL INCREASE FROM WHERE IT WAS YDY ..TO ABOUT 1.6
OR 1.7 INCHES AND THAT WIND FIELDS ALOFT SHOULD DECREASE SO OTHER
THAN A WET MICROBURST...SVR WIND DOESN`T SEEM TO BE A BIG PROBLEM.
THERE MIGHT BE A STRONG MESOCYCLONE FOR A SHORT TIME LATE TODAY
ALONG THE BOUNDARY THAT SEEMS TO EVOLVE RAPIDLY SOUTHWARD THROUGH
SOUTHERN NEW JERSEY LATE TODAY. THE SHORT WAVE AT MID LVLS PASSING
ACROSS THE DELMARVA THIS EVENING ALSO GENERATES A WEAK LOW
PRESSURE SYSTEM AT 700MB WHICH MEANS SLOWER STEERING FLOW.
NO FLASH FLOOD WATCH TODAY BUT CONCERN EXISTS FOR SLOW MOVING
TORRENTIAL RAINS CAUSING A COUPLE OF STREAMS IN SE PA...NORTHERN
DE AND OR S NJ TO RISE RAPIDLY INTO FLOOD, OR FFW FOR A COUPLE OF
COUNTIES AS OCCURRED LAST EVENING IN KENT COUNTY MD.
1 HR FFG IS AS LOW AS .8 INCHES IN NE NJ.
SO...WHILE ITS DIFFICULT TO BE SURE WHERE CONVECTION WILL BE MOST
WIDESPREAD AND HEAVIEST...THE FCST HAS WORDING FOR THE POSSIBILITY
HEAVY SHOWERS.
THE TEMPS DEWS AND WINDS ARE 50 50 BLENDED NAM/GFS 00Z/18 MOS
GUIDANCE. MAX TEMPS SHOULD BE IN THE 17-19Z TIME FRAME.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
CONVECTION MAY STILL BE QUITE ACTIVE THROUGH THE 10 PM TO MIDNIGHT
TIME FRAME THEN GRADUALLY DIE OUT AS NLY FLOW DEVELOPS IN THE
WAKE OF THE SOUTHWARD CFP AND ASSTD SFC LOW MOVING SEAWARD FROM E
OF THE NJ/DE COASTS.
STRATUS IS LIKELY FOR AT LEAST THE S PTN OF THE AREA AS MODELED IN
1000-950 MB RH FIELDS... AS WELL AS SREF PROBS OF CIGS BLO 1000
AND 3000 FT. THE LATTER CIGS MAY BE ARRIVING ON NE FLOW FROM LI
TONIGHT. TIMING ARRIVAL AND CIG HT UNCERTAIN. GUIDANCE SUGGESTS
MOSTLY E OF THE NJT THEN DOWN ACROSS SE DE.
TEMPS/DEWS/WINDS ARE 50 50 BLENDED 00Z/18 NAM/GFS MOS GUIDANCE.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
THE PERIOD BEGINS WITH THE DEPARTING COLD FRONT AND LOW. SURFACE
HIGH PRESSURE BUILDS INTO THE REGION ON WEDNESDAY NIGHT WITH THE
CENTER OF THE HIGH MOVING OFF THE COAST ON THURSDAY. A REINFORCING
SHOT OF CANADIAN HIGH PRESSURE MOVES OFF THE COAST ON FRIDAY. HIGH
PRESSURE REMAINS IN PLACE ON SATURDAY BEFORE GETTING COMPRESSED ON
SUNDAY. A COLD FRONT WILL EITHER APPROACH OR DROP INTO THE REGION ON
MONDAY.
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT ARE POPLESS. POPS GET BACK IN
THE GRIDS STARTING ON FRIDAY ACROSS THE FAR NORTHWEST AND THAN
SPREAD SOUTH AND EAST OVER THE WEEKEND IN THE PERSISTENT RETURN FLOW.
BESIDES HELPING TO INCREASE POPS, THE RETURN FLOW AROUND THE
OFFSHORE HIGH WILL ALSO BRING AN INCREASE IN HEAT AND HUMIDITY.
TEMPERATURES WILL START OFF A LITTLE BELOW NORMAL IN THE EXTENDED
AND CLIMB TO THE ABOVE NORMAL RANGE SATURDAY OR SUNDAY.
&&
.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
TODAY...PATCHES OF IFR/MVFR CIGS THIS MORNING WHICH SHOULD LIFT TO
VFR OVER THE NEXT HOUR OR TWO. SLOW MOVING SHOWERS AND TSTMS WITH
THEIR TORRENTIAL RAINS AND POSSIBLY N-NW G30-35 KT THIS AFTN MAY
PRODUCE LOCAL IFR/MVFR RESTRICTIONS...AGAIN. TIMING AND INTENSITY
OF CONVECTION AT ANY TAF LOCATION IS UNCERTAIN AND THEREFORE
THUNDER IS NOT CONFIDENTLY DEFINED IN THE 12Z TAFS. LIGHT WIND
BECOMING SSW FOR A TIME MIDDAY AT 10-15 KT THEN SHIFTING N LATE.
TONIGHT...LEFTOVER IFR CONDS IN HEAVY SHOWERS AND TSTMS BECOMING
IFR CONDS IN ST/FOG LATE. N WIND BECOMING NNE 10-15 KT LATE.
OUTLOOK...
WEDNESDAY...POCKETS OF MVFR CONDITIONS IN THE MORNING, OTHERWISE
VFR.
WEDNESDAY NIGHT THROUGH SATURDAY...VFR EXCEPT IN MORNING FOG/HAZE OR
SHOWERS/THUNDERSTORMS.
&&
.MARINE...
SUB-ADVISORY CONDITIONS LOOK TO PERSIST ACROSS OUR WATERS THROUGH
MOST OF TONIGHT BUT SCA CONDITIONS MAY DEVELOP ALONG PORTIONS OF OUR
COASTS AFTER MIDNIGHT. THE CWF WORDING HAS 3 TO 5 FT SEAS AND NO SCA
ATTM BUT THE POTENTIAL EXISTS FOR 5 FOOTERS LATE AND POSSIBLY NE
WIND GUSTS TO 22 KT LATE THIS COMING TUE NIGHT.
OUTLOOK...
A SHORT PERIOD SMALL CRAFT ADVISORY MAY BE NEEDED EARLY WEDNESDAY
BEHIND THE DEPARTING COLD FRONT. OUTSIDE OF THIS, NO HEADLINES ARE
EXPECTED THROUGH SATURDAY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KRUZDLO
NEAR TERM...DRAG/HEAVENER
SHORT TERM...DRAG
LONG TERM...KRUZDLO
AVIATION...DRAG/KRUZDLO
MARINE...DRAG/KRUZDLO
000
FXUS61 KPHI 181013
AFDPHI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
613 AM EDT TUE JUN 18 2013
.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH THE FORECAST AREA TODAY AND TONIGHT
WITH WEAK LOW PRESSURE FORMING ALONG IT. A HIGH PRESSURE SYSTEM WILL
THEN BUILD INTO THE NORTHEAST AND MID-ATLANTIC TOMORROW. THE CENTER
OF THE HIGH WILL SHIFT OFFSHORE ON THURSDAY AND REMAIN IN PLACE
THROUGH THE WEEKEND. A RETURN FLOW AROUND THE HIGH WILL BRING AN
INCREASE IN HEAT AND HUMIDITY AND A THREAT OF SCATTERED SHOWERS AND
THUNDERSTORMS THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
630 AM ESTF UPDATE: AT 6AM...NO SIGNIFICANT CHANGE TO THE FORECAST
ISSUED AT 330 AM.
NO FLASH FLOOD WATCH TODAY BUT CONCERN EXISTS FOR SLOW MOVING
TORRENTIAL RAINS CAUSING A COUPLE OF STREAMS IN SE PA...NORTHERN
DE AND OR S NJ TO RISE RAPIDLY INTO FLOOD, OR FFW FOR A COUPLE OF
COUNTIES AS OCCURRED LAST EVENING IN KENT COUNTY MD.
1 HR FFG IS AS LOW AS .8 INCHES IN NE NJ.
SO...WHILE ITS DIFFICULT TO BE SURE WHERE CONVECTION WILL BE MOST
WIDESPREAD AND HEAVIEST...THE FCST HAS WORDING FOR THE POSSIBILITY
HEAVY SHOWERS.
WE DO KNOW PWAT WILL INCREASE FROM WHERE IT WAS YDY ..TO ABOUT 1.6
OR 1.7 INCHES AND THAT WIND FIELDS ALOFT SHOULD DECREASE THROUGH THE
DAY SO OTHER THAN A WET MICROBURST...SVR WIND DOESNT SEEM TO BE A
BIG PROBLEM. THERE MIGHT BE A STRONG MESOCYCLONE FOR A SHORT TIME
LATE TODAY ALONG THE BOUNDARY THAT SEEMS TO EVOLVE RAPIDLY SOUTHWARD
THROUGH SOUTHERN NEW JERSEY LATE TODAY. THE SHORT WAVE AT MID LVLS
PASSING ACROSS THE DELMARVA THIS EVENING ALSO GENERATES A WEAK
LOW PRESSURE SYSTEM AT 700MB WHICH MEANS SLOWER STEERING FLOW.
AS IT STANDS AT 6 AM...LOOKS LIKE NO CONVECTION THRU ABOUT 15Z
THEN MODELS START SPEWING QPF AT VARIOUS TIMES THE REMAINDER OF
THE DAY. COSPA ERUPTS WITH ITS CONVECTION IN THE 15-16Z TIME FRAME
S NJ..DE AND E MD. THIS DIFFERS FROM TWO OTHER SIMULATIONS WE`VE
REVIEWED (NSSL WRF AND SPC WRF).
SKY COVER: PATCHY EM FOG BURNS OFF BY 7 AM...OTRW CONSIDERABLE
CLOUDINESS TODAY...ESPECIALLY THIS AFTN.
THE TEMPS DEWS AND WINDS ARE 50 50 BLENDED NAM/GFS 00Z/18 MOS
GUIDANCE. MAX TEMPS SHOULD BE IN THE 17-19Z TIME FRAME.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
CONVECTION MAY STILL BE QUITE ACTIVE THROUGH THE 10 PM TO MIDNIGHT
TIME FRAME THEN GRADUALLY DIE OUT AS NLY FLOW DEVELOPS IN THE
WAKE OF THE SOUTHWARD CFP AND ASSTD SFC LOW MOVING SEAWARD FROM E
OF THE NJ/DE COASTS.
STRATUS IS LIKELY FOR AT LEAST THE S PTN OF THE AREA AS MODELED IN
1000-950 MB RH FIELDS... AS WELL AS SREF PROBS OF CIGS BLO 1000
AND 3000 FT. THE LATTER CIGS MAY BE ARRIVING ON NE FLOW FROM LI
TONIGHT. TIMING ARRIVAL AND CIG HT UNCERTAIN. GUIDANCE SUGGESTS
MOSTLY E OF THE NJT THEN DOWN ACROSS SE DE.
TEMPS/DEWS/WINDS ARE 50 50 BLENDED 00Z/18 NAM/GFS MOS GUIDANCE.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
THE PERIOD BEGINS WITH THE DEPARTING COLD FRONT AND LOW. SURFACE
HIGH PRESSURE BUILDS INTO THE REGION ON WEDNESDAY NIGHT WITH THE
CENTER OF THE HIGH MOVING OFF THE COAST ON THURSDAY. A REINFORCING
SHOT OF CANADIAN HIGH PRESSURE MOVES OFF THE COAST ON FRIDAY. HIGH
PRESSURE REMAINS IN PLACE ON SATURDAY BEFORE GETTING COMPRESSED ON
SUNDAY. A COLD FRONT WILL EITHER APPROACH OR DROP INTO THE REGION ON
MONDAY.
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT ARE POPLESS. POPS GET BACK IN
THE GRIDS STARTING ON FRIDAY ACROSS THE FAR NORTHWEST AND THAN
SPREAD SOUTH AND EAST OVER THE WEEKEND IN THE PERSISTENT RETURN FLOW.
BESIDES HELPING TO INCREASE POPS, THE RETURN FLOW AROUND THE
OFFSHORE HIGH WILL ALSO BRING AN INCREASE IN HEAT AND HUMIDITY.
TEMPERATURES WILL START OFF A LITTLE BELOW NORMAL IN THE EXTENDED
AND CLIMB TO THE ABOVE NORMAL RANGE SATURDAY OR SUNDAY.
&&
.AVIATION /10Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
THROUGH 12Z...BKN CIRRUS CIGS. PATCHY MVFR VSBY IN FOG.
AFTER 12Z...VFR CIGS WITH CLUSTERS OF IFR SLOW MOVING SHOWERS AND
TSTMS WITH THEIR TORRENTIAL RAINS AND POSSIBLY N-NW G30-35 KT
THIS AFTN. TIMING AND INTENSITY OF CONVECTION AT ANY TAF LOCATION
IS UNCERTAIN AND THEREFORE THUNDER IS NOT CONFIDENTLY DEFINED IN
THE UPCOMING 12Z TAFS. LIGHT WIND BECOMING SSW FOR A TIME MIDDAY
AT 10-15 KT THEN SHIFTING N LATE.
TONIGHT...LEFTOVER IFR CONDS IN HEAVY SHOWERS AND TSTMS BECOMING
IFR CONDS IN ST/FOG LATE. N WIND BECOMING NNE 10-15 KT LATE.
OUTLOOK...
WEDNESDAY...POCKETS OF MVFR CONDITIONS IN THE MORNING, OTHERWISE
VFR.
WEDNESDAY NIGHT THROUGH SATURDAY...VFR EXCEPT IN MORNING FOG/HAZE OR
SHOWERS/THUNDERSTORMS.
&&
.MARINE...
SUB-ADVISORY CONDITIONS LOOK TO PERSIST ACROSS OUR WATERS THROUGH
MOST OF TONIGHT BUT SCA CONDITIONS MAY DEVELOP ALONG PORTIONS OF OUR
COASTS AFTER MIDNIGHT. THE CWF WORDING HAS 3 TO 5 FT SEAS AND NO SCA
ATTM BUT THE POTENTIAL EXISTS FOR 5 FOOTERS LATE AND POSSIBLY NE
WIND GUSTS TO 22 KT LATE THIS COMING TUE NIGHT.
OUTLOOK...
A SHORT PERIOD SMALL CRAFT ADVISORY MAY BE NEEDED EARLY WEDNESDAY
BEHIND THE DEPARTING COLD FRONT. OUTSIDE OF THIS, NO HEADLINES ARE
EXPECTED THROUGH SATURDAY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KRUZDLO
NEAR TERM...DRAG 612A
SHORT TERM...DRAG 612A
LONG TERM...KRUZDLO
AVIATION...DRAG/KRUZDLO 612A
MARINE...DRAG/KRUZDLO 612A
000
FXUS61 KPHI 180812
AFDPHI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
412 AM EDT TUE JUN 18 2013
.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH THE FORECAST AREA TODAY AND TONIGHT
WITH WEAK LOW PRESSURE FORMING ALONG IT. A HIGH PRESSURE SYSTEM WILL
THEN BUILD INTO THE NORTHEAST AND MID-ATLANTIC TOMORROW. THE CENTER
OF THE HIGH WILL SHIFT OFFSHORE ON THURSDAY AND REMAIN IN PLACE
THROUGH THE WEEKEND. A RETURN FLOW AROUND THE HIGH WILL BRING AN
INCREASE IN HEAT AND HUMIDITY AND A THREAT OF SCATTERED SHOWERS AND
THUNDERSTORMS THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NO FLASH FLOOD WATCH TODAY BUT CONCERN EXISTS FOR SLOW MOVING
TORRENTIAL RAINS CAUSING A COUPLE OF STREAMS IN SE PA...NORTHERN DE
AND OR S NJ TO RISE RAPIDLY INTO FLOOD, OR FFW FOR A COUPLE OF
COUNTIES AS OCCURRED LAST EVENING IN KENT COUNTY MD.
1 HR FFG IS AS LOW AS .8 INCHES IN NE NJ.
SO...WHILE ITS DIFFICULT TO BE SURE WHERE CONVECTION WILL BE MOST
WIDESPREAD AND HEAVIEST...THE FCST HAS WORDING FOR THE POSSIBILITY
HEAVY SHOWERS.
WE DO KNOW PWAT WILL INCREASE FROM WHERE IT WAS YDY ..TO ABOUT 1.6
OR 1.7 INCHES AND THAT WIND FIELDS ALOFT SHOULD DECREASE THROUGH THE
DAY SO OTHER THAN A WET MICROBURST...SVR WIND DOESNT SEEM TO BE A
BIG PROBLEM. THERE MIGHT BE A STRONG MESOCYCLONE FOR A SHORT TIME
LATE TODAY ALONG THE BOUNDARY THAT SEEMS TO EVOLVE RAPIDLY SOUTHWARD
THROUGH SOUTHERN NEW JERSEY LATE TODAY. THE SHORT WAVE AT MID LVLS
PASSING ACROSS THE DELMARVA THIS EVENING ALSO GENERATES A WEAK
LOW PRESSURE SYSTEM AT 700MB WHICH MEANS SLOWER STEERING FLOW.
AS IT STANDS AT 330 AM...LOOKS LIKE NO CONVECTION THRU ABOUT 15Z
THEN MODELS START SPEWING QPF AT VARIOUS TIMES THE REMAINDER OF
THE DAY. COSPA ERUPTS WITH ITS CONVECTION IN THE 15-16Z TIME FRAME
S NJ..DE AND E MD. THIS DIFFERS FROM TWO OTHER SIMULATIONS WE`VE
LOOKED AT (NSSL WRF AND SPC WRF).
SKY COVER: PATCHY EM FOG...OTRW CONSIDERABLE CLOUDINESS
TODAY...ESPECIALLY THIS AFTN.
THE TEMPS DEWS AND WINDS ARE 50 50 BLENDED NAM/GFS 00Z/18 MOS
GUIDANCE. MAX TEMPS SHOULD BE IN THE 17-19Z TIME FRAME.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
CONVECTION MAY STILL BE QUITE ACTIVE THROUGH THE 10 PM TO MIDNIGHT
TIME FRAME THEN GRADUALLY DIE OUT AS NLY FLOW DEVELOPS IN THE
WAKE OF THE SOUTHWARD CFP AND ASSTD SFC LOW MOVING SEAWARD FROM E
OF THE NJ/DE COASTS.
STRATUS IS LIKELY FOR AT LEAST THE S PTN OF THE AREA AS MODELED IN
1000-950 MB RH FIELDS... AS WELL AS SREF PROBS OF CIGS BLO 1000
AND 3000 FT. THE LATTER CIGS MAY BE ARRIVING ON NE FLOW FROM LI
TONIGHT. TIMING ARRIVAL AND CIG HT UNCERTAIN.
TEMPS/DEWS/WINDS ARE 50 50 BLENDED 00Z/18 NAM/GFS MOS GUIDANCE.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
THE PERIOD BEGINS WITH THE DEPARTING COLD FRONT AND LOW. SURFACE
HIGH PRESSURE BUILDS INTO THE REGION ON WEDNESDAY NIGHT WITH THE
CENTER OF THE HIGH MOVING OFF THE COAST ON THURSDAY. A REINFORCING
SHOT OF CANADIAN HIGH PRESSURE MOVES OFF THE COAST ON FRIDAY. HIGH
PRESSURE REMAINS IN PLACE ON SATURDAY BEFORE GETTING COMPRESSED ON
SUNDAY. A COLD FRONT WILL EITHER APPROACH OR DROP INTO THE REGION ON
MONDAY.
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT ARE POPLESS. POPS GET BACK IN
THE GRIDS STARTING ON FRIDAY ACROSS THE FAR NORTHWEST AND THAN
SPREAD SOUTH AND EAST OVER THE WEEKEND IN THE PERSISTENT RETURN FLOW.
BESIDES HELPING TO INCREASE POPS, THE RETURN FLOW AROUND THE
OFFSHORE HIGH WILL ALSO BRING AN INCREASE IN HEAT AND HUMIDITY.
TEMPERATURES WILL START OFF A LITTLE BELOW NORMAL IN THE EXTENDED
AND CLIMB TO THE ABOVE NORMAL RANGE SATURDAY OR SUNDAY.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
THROUGH 12Z...BKN CIRRUS CIGS. PATCHY MVFR VSBY IN FOG.
AFTER 12Z...VFR CIGS WITH CLUSTERS OF IFR SLOW MOVING SHOWERS AND
TSTMS WITH THEIR TORRENTIAL RAINS AND POSSIBLY N-NW G 30-35 KT
THIS AFTN. TIMING AND INTENSITY OF CONVECTION AT ANY TAF LOCATION
IS UNCERTAIN AND THEREFORE THUNDER IS NOT DEFINED IN THE 06Z TAFS.
LIGHT WIND BECOMING SSW FOR A TIME MIDDAY AT 10-15 KT THEN SHIFTING
N LATE.
TONIGHT...LEFTOVER IFR CONDS IN HEAVY SHOWERS AND TSTMS BECOMING
IFR CONDS IN ST/FOG LATE. N WIND BECOMING NNE 10-15 KT LATE.
OUTLOOK...
WEDNESDAY...POCKETS OF MVFR CONDITIONS IN THE MORNING, OTHERWISE
VFR.
WEDNESDAY NIGHT THROUGH SATURDAY...VFR EXCEPT IN MORNING FOG/HAZE OR
SHOWERS/THUNDERSTORMS.
&&
.MARINE...
SUB-ADVISORY CONDITIONS LOOK TO PERSIST ACROSS OUR WATERS THROUGH
MOST OF TUE NIGHT BUT SCA CONDITIONS MAY DEVELOP VCNTY SANDY HOOK
LATE THIS TUE NIGHT.
OUTLOOK...
A SHORT PERIOD SMALL CRAFT ADVISORY MAY BE NEEDED EARLY WEDNESDAY
BEHIND THE DEPARTING COLD FRONT. OUTSIDE OF THIS, NO HEADLINES ARE
EXPECTED THROUGH SATURDAY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KRUZDLO
NEAR TERM...DRAG 411
SHORT TERM...DRAG 411
LONG TERM...KRUZDLO
AVIATION...DRAG/KRUZDLO 411
MARINE...DRAG/KRUZDLO 411
000
FXUS61 KPHI 180748
AFDPHI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
348 AM EDT TUE JUN 18 2013
.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH THE FORECAST AREA TODAY AND TONIGHT
WITH WEAK LOW PRESSURE FORMING ALONG IT. A HIGH PRESSURE SYSTEM WILL
THEN BUILD INTO THE NORTHEAST AND MID-ATLANTIC TOMORROW. THE CENTER
OF THE HIGH WILL SHIFT OFFSHORE ON THURSDAY AND REMAIN IN PLACE
THROUGH THE WEEKEND. A RETURN FLOW AROUND THE HIGH WILL BRING AN
INCREASE IN HEAT AND HUMIDITY AND A THREAT OF SCATTERED SHOWERS AND
THUNDERSTORMS THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
STILL TRYING TO FIGURE OUT A BEST FCST SCENARIO:
AS IT STANDS AT 2 AM...LOOKS LIKE NO CONVECTION THRU ABOUT
15Z THEN MODELS START SPEWING AT VARIOUS TIMES OF THE DAY.
WE DO KNOW PWAT WILL INCREASE FROM WHERE IT WAS YDY ..TO ABOUT 1.6
OR 1.7 INCHES AND THAT WIND FIELDS ALOFT SHOULD DECREASE THROUGH
THE DAY SO OTHER THAN A WET MICROBURST...SVR WIND DOESNT SEEM TO
BE A BIG PROBLEM. THERE MIGHT BE A STRONG MESOCYCLONE FOR A SHORT
TIME LATE TODAY ALONG THE BOUNDARY THAT SEEMS TO EVOLVE RAPIDLY
SOUTHWARD THROUGH SOUTHERN NEW JERSEY LATE TODAY.
THE TEMPS DEWS AND WINDS ARE 50 50 BLENDED NAM/GFS 00Z/18 MOS
GUIDANCE AND ADDED A DEGREE FOR LATER THAN MODELED CONVECTION. MAX
TEMPS SHOULD BE IN THE 17-19Z TIME FRAME.
CONSIDERABLE CLOUDINESS TODAY...ESPECIALLY THIS AFTN.
ITS DIFFICULT FOR ME TO BE SURE WHERE CONVECTION WILL BE MOST
WIDESPREAD BUT THE WORDING FOR POSSIBLE HEAVY SHOWERS WILL BE IN
THE FCST.
THE POSSIBILITY EXISTS FOR FFW DEL VALLEY SEWD NEAR THE SFC LOW/CFP
AS IT EVOLVES SOUTHWARD THIS AFTN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
CONVECTION MAY STILL BE QUITE ACTIVE THROUGH THE 10 PM TO MIDNIGHT
TIME FRAME THEN GRADUALLY DIE OUT AS NLY FLOW DEVELOPS IN THE
WAKE OF THE SOUTHWARD CFP AND ASSTD SFC LOW MOVING SEAWARD FROM E
OF THE NJ/DE COASTS.
STRATUS IS LIKELY FOR AT LEAST THE S PTN OF THE AREA AS MODELED IN
1000-950 MB RH FIELDS... AS WELL AS SREF PROBS OF CIGS BLO 1000
AND 3000 FT. THE LATTER CIGS MAY BE ARRIVING ON NE FLOW FROM LI
TONIGHT. TIMING ARRIVAL AND CIG HT UNCERTAIN.
TEMPS/DEWS/WINDS ARE 50 50 BLENDED 00Z/18 NAM/GFS MOS GUIDANCE.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
THE PERIOD BEGINS WITH THE DEPARTING COLD FRONT AND LOW. SURFACE
HIGH PRESSURE BUILDS INTO THE REGION ON WEDNESDAY NIGHT WITH THE
CENTER OF THE HIGH MOVING OFF THE COAST ON THURSDAY. A REINFORCING
SHOT OF CANADIAN HIGH PRESSURE MOVES OFF THE COAST ON FRIDAY. HIGH
PRESSURE REMAINS IN PLACE ON SATURDAY BEFORE GETTING COMPRESSED ON
SUNDAY. A COLD FRONT WILL EITHER APPROACH OR DROP INTO THE REGION ON
MONDAY.
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT ARE POPLESS. POPS GET BACK IN
THE GRIDS STARTING ON FRIDAY ACROSS THE FAR NORTHWEST AND THAN
SPREAD SOUTH AND EAST OVER THE WEEKEND IN THE PERSISTENT RETURN FLOW.
BESIDES HELPING TO INCREASE POPS, THE RETURN FLOW AROUND THE
OFFSHORE HIGH WILL ALSO BRING AN INCREASE IN HEAT AND HUMIDITY.
TEMPERATURES WILL START OFF A LITTLE BELOW NORMAL IN THE EXTENDED
AND CLIMB TO THE ABOVE NORMAL RANGE SATURDAY OR SUNDAY.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
THROUGH 12Z...BKN CIRRUS CIGS. PATCHY MVFR VSBY IN FOG.
AFTER 12Z...VFR CIGS WITH CLUSTERS OF IFR SLOW MOVING SHOWERS AND
TSTMS WITH THEIR TORRENTIAL RAINS AND POSSIBLY N-NW G 30-35 KT
THIS AFTN. TIMING AND INTENSITY OF CONVECTION AT ANY TAF LOCATION
IS UNCERTAIN AND THEREFORE THUNDER IS NOT DEFINED IN THE 06Z TAFS.
LIGHT WIND BECOMING SSW FOR A TIME MIDDAY AT 10-15 KT THEN SHIFTING
N LATE.
TONIGHT...LEFTOVER IFR CONDS IN HEAVY SHOWERS AND TSTMS BECOMING
IFR CONDS IN ST/FOG LATE. N WIND BECOMING NNE 10-15 KT LATE.
OUTLOOK...
WEDNESDAY...POCKETS OF MVFR CONDITIONS IN THE MORNING, OTHERWISE
VFR.
WEDNESDAY NIGHT THROUGH SATURDAY...VFR EXCEPT IN MORNING FOG/HAZE OR
SHOWERS/THUNDERSTORMS.
&&
.MARINE...
SUB-ADVISORY CONDITIONS LOOK TO PERSIST ACROSS OUR WATERS THROUGH
MOST OF TUE NIGHT BUT SCA CONDITIONS MAY DEVELOP VCNTY SANDY HOOK
LATE THIS TUE NIGHT.
OUTLOOK...
A SHORT PERIOD SMALL CRAFT ADVISORY MAY BE NEEDED EARLY WEDNESDAY
BEHIND THE DEPARTING COLD FRONT. OUTSIDE OF THIS, NO HEADLINES ARE
EXPECTED THROUGH SATURDAY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KRUZDLO
NEAR TERM...DRAG
SHORT TERM...DRAG
LONG TERM...KRUZDLO
AVIATION...DRAG/KRUZDLO
MARINE...DRAG/KRUZDLO
000
FXUS61 KPHI 180620
AFDPHI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
220 AM EDT TUE JUN 18 2013
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL CONTINUE TO MOVE NORTHEAST THROUGH THE
SAINT LAWRENCE VALLEY TONIGHT. ITS ASSOCIATED COLD FRONT SHOULD
ARRIVE TUESDAY OR TUESDAY NIGHT WITH A WEAK LOW PRESSURE SYSTEM
FORMING ALONG IT. A HIGH PRESSURE SYSTEM WILL THEN BUILD INTO THE
NORTHEAST THE LATTER HALF OF THE WORK WEEK BEFORE SHIFTING
OFFSHORE ON SATURDAY. A WARM FRONT IS FORECAST TO MOVE THROUGH THE
FORECAST AREA ON SUNDAY AND NORTHWARD INTO NEW ENGLAND ON MONDAY.
&&
.NEAR TERM /THROUGH TODAY/...
STILL TRYING TO FIGURE OUT A BEST FCST SCENARIO:
AS IT STANDS AT 2 AM...LOOKS LIKE NO CONVECTION THRU ABOUT
15Z THEN MODELS START SPEWING AT VARIOUS TIMES OF THE DAY.
WE DO KNOW PWAT WILL INCREASE FROM WHERE IT WAS YDY ..TO ABOUT 1.6
OR 1.7 INCHES AND THAT WIND FIELDS ALOFT SHOULD DECREASE THROUGH
THE DAY SO OTHER THAN A WET MICROBURST...SVR WIND DOESNT SEEM TO
BE A BIG PROBLEM. THERE MIGHT BE A STRONG MESOCYCLONE FOR A SHORT
TIME LATE TODAY ALONG THE BOUNDARY THAT SEEMS TO EVOLVE RAPIDLY
SOUTHWARD THROUGH SOUTHERN NEW JERSEY LATE TODAY.
THE TEMPS DEWS AND WINDS ARE 50 50 BLENDED NAM/GFS 00Z/18 MOS
GUIDANCE AND ADDED A DEGREE FOR LATER THAN MODELED CONVECTION. MAX
TEMPS SHOULD BE IN THE 17-19Z TIME FRAME.
CONSIDERABLE CLOUDINESS TODAY...ESPECIALLY THIS AFTN.
ITS DIFFICULT FOR ME TO BE SURE WHERE CONVECTION WILL BE MOST
WIDESPREAD BUT THE WORDING FOR POSSIBLE HEAVY SHOWERS WILL BE IN
THE FCST.
THE POSSIBILITY EXISTS FOR FFW DEL VALLEY SEWD NEAR THE SFC LOW/CFP
AS IT EVOLVES SOUTHWARD THIS AFTN.
&&
.SHORT TERM /TONIGHT/...
CONVECTION MAY STILL BE QUITE ACTIVE THROUGH THE 10 PM TO MIDNIGHT
TIME FRAME THEN GRADUALLY DIE OUT AS NLY FLOW DEVELOPS IN THE
WAKE OF THE SOUTHWARD CFP AND ASSTD SFC LOW MOVING SEAWARD FROM E
OF THE NJ/DE COASTS.
STRATUS IS LIKELY FOR AT LEAST THE S PTN OF THE AREA AS MODELED IN
1000-950 MB RH FIELDS... AS WELL AS SREF PROBS OF CIGS BLO 1000
AND 3000 FT. THE LATTER CIGS MAY BE ARRIVING ON NE FLOW FROM LI
TONIGHT. TIMING ARRIVAL AND CIG HT UNCERTAIN.
TEMPS/DEWS/WINDS ARE 50 50 BLENDED 00Z/18 NAM/GFS MOS GUIDANCE.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
HIGH PRESSURE PUSHES INTO THE REGION FOR THE THURSDAY THROUGH
SATURDAY TIME-FRAME, WITH TEMPERATURES RUNNING SLIGHTLY BELOW
NORMAL AND DRY CONDITIONS.
WARM FRONTAL BOUNDARY APPROACH ON SUNDAY BRINGS NEXT POTENTIAL
PRECIPITATION AND BOTH TEMPS AND POPS ON SUNDAY AND MONDAY
FOLLOWED WPC GUIDANCE CLOSELY.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
THROUGH 12Z...BKN CIRRUS CIGS. PATCHY MVFR VSBY IN FOG.
AFTER 12Z...VFR CIGS WITH CLUSTERS OF IFR SLOW MOVING SHOWERS AND
TSTMS WITH THEIR TORRENTIAL RAINS AND POSSIBLY N-NW G 30-35 KT
THIS AFTN. TIMING AND INTENSITY OF CONVECTION AT ANY TAF LOCATION
IS UNCERTAIN AND THEREFORE THUNDER IS NOT DEFINED IN THE 06Z TAFS.
LIGHT WIND BECOMING SSW FOR A TIME MIDDAY AT 10-15 KT THEN SHIFTING
N LATE.
TONIGHT...LEFTOVER IFR CONDS IN HEAVY SHOWERS AND TSTMS BECOMING
IFR CONDS IN ST/FOG LATE. N WIND BECOMING NNE 10-15 KT LATE.
OUTLOOK...
WEDNESDAY...POCKETS OF MVFR CONDITIONS IN THE MORNING, OTHERWISE
VFR.
WEDNESDAY NIGHT THROUGH SATURDAY...VFR.
&&
.MARINE...
SUB-ADVISORY CONDITIONS LOOK TO PERSIST ACROSS OUR WATERS THROUGH
MOST OF TUE NIGHT BUT SCA CONDITIONS MAY DEVELOP VCNTY SANDY HOOK
LATE THIS TUE NIGHT.
OUTLOOK...
RIGHT NOW WE ARE NOT LOOKING AT SCA CONDITIONS TO OCCUR THROUGH
SATURDAY. HOWEVER, THE NORTHEAST FETCH LATE WEDNESDAY INTO
WEDNESDAY NIGHT AND EARLY THURSDAY WILL BRING SEAS UP TO THE 4
FOOT RANGE, SO THIS WILL CONTINUE TO BE MONITORED CLOSELY. WINDS
AND SEAS SUBSIDE AS WE MOVE INTO FRIDAY AND SATURDAY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...SZATKOWSKI
NEAR TERM...DRAG 220
SHORT TERM...DRAG 220
LONG TERM...SZATKOWSKI
AVIATION...DRAG/SZATKOWSKI 220
MARINE...DRAG/SZATKOWSKI 220
000
FXUS61 KPHI 180119
AFDPHI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
919 PM EDT MON JUN 17 2013
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL CONTINUE TO MOVE NORTHEAST THROUGH THE
SAINT LAWRENCE VALLEY TONIGHT. ITS ASSOCIATED COLD FRONT SHOULD
ARRIVE TUESDAY OR TUESDAY NIGHT WITH A WEAK LOW PRESSURE SYSTEM
FORMING ALONG IT. A HIGH PRESSURE SYSTEM WILL THEN BUILD INTO THE
NORTHEAST THE LATTER HALF OF THE WORK WEEK BEFORE SHIFTING
OFFSHORE ON SATURDAY. A WARM FRONT IS FORECAST TO MOVE THROUGH THE
FORECAST AREA ON SUNDAY AND NORTHWARD INTO NEW ENGLAND ON MONDAY.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
MORE SHORT TERM ADJUSTMENTS TO WX/POPS ACROSS THE DELMARVA AND SRN
NJ WITH A CONTINUATION OF SHOWERS/SCT TSTMS ACROSS THE REGION.
PCPN WILL GRADUALLY END OVERNIGHT. PATCHY FOG IS EXPECTED.
TEMPERATURES WERE NOT CHANGED MUCH FROM EARLIER FCST.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
FRONTAL BOUNDARY WILL CONTINUE TO SLOWLY SAG ACROSS THE REGION
TOMORROW AND AGAIN TOUCH OFF SHOWERS AND POSSIBLY THUNDERSTORMS BY
THE LATE MORNING/EARLY AFTERNOON TIME-FRAME. A WEAK SURFACE WAVE WILL
MOVE ALONG THE FRONT WHICH HELPS WITH LARGER SCALE LIFT IN A
MARGINALLY UNSTABLE ATMOSPHERE...MORE CLOUD COVER TOMORROW THAN
TODAY. STILL NOT QUITE SURE HOW MUCH SURFACE BASED INSTABILITY CAN
BE REALIZED TOMORROW.
THE FLOW ALOFT, WHICH ONCE WAS STRONG, CONTINUES TO WEAKEN ON
TUESDAY SO ANY STORMS THAT DO INITIATE ALONG THE FRONTAL BOUNDARY
ALLOWING FOR A MUCH SLOWER STORM MOTION. PWATS WILL STILL BE FAIRLY
HIGH SO ANY SHOWER/THUNDERSTORM COULD PRODUCE A HEAVY DOWNPOUR IN A
SHORT TIME PERIOD.
TEMPERATURES TOMORROW SHOULD BE A COUPLE OF DEGREES COOLER THAN
TODAY WITH HIGHS IN THE LOW TO MID-80S.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
TIME PERIOD BEGINS WITH COLD FRONTAL BOUNDARY WORKING TO PUSH
THROUGH THE AREA. COLD FRONTAL MOVEMENT STILL LOOKS SLOWER THAN
IT DID SEVERAL DAYS AGO, SO RETAINED THE CHANCE POPS FOR
BOTH TUE NIGHT AND WED, WITH THE HIGHER POPS ON WEDNESDAY CLOSER
TO THE COAST. LOOKED AT BLEND OF MAV/MET ON TUE NIGHT/WEDNESDAY
FOR TEMPERATURES.
HIGH PRESSURE PUSHES INTO THE REGION FOR THE THURSDAY THROUGH
SATURDAY TIME-FRAME, WITH TEMPERATURES RUNNING SLIGHTLY BELOW
NORMAL AND DRY CONDITIONS.
WARM FRONTAL BOUNDARY APPROACH ON SUNDAY BRINGS NEXT POTENTIAL
PRECIPITATION AND BOTH TEMPS AND POPS ON SUNDAY AND MONDAY
FOLLOWED WPC GUIDANCE CLOSELY.
&&
.AVIATION /01Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
TONIGHT...THE CONVECTION ACROSS SRN NJ WILL END OVERNIGHT. MOSTLY
VFR INTO THE EVENING...THEN AREAS OF FOG MAY DEVELOP WITH LOWER
VSBYS EXPECTED. WINDS WILL BECOME LIGHT VARIABLE OR CALM
OVERNIGHT.
TUESDAY...MVFR POSSIBLY EARLY IN THE MORNING WITH FOG ACROSS A
MAJORITY OF OUR TERMINALS, THEN VFR. THE LIGHT VARIABLE/CALM WINDS
WILL BEGIN TO PICK UP BY LATE MORNING AND BE MORE SOUTHEASTERLY AS A
LOW PRESSURE SYSTEM MAKES ITS WAY ALONG THE FRONTAL BOUNDARY ACROSS
OUR AREA. THIS WILL PROVIDE ANOTHER CHANCE AT SHOWERS AND
THUNDERSTORMS WITH MVFR RESTRICTIONS.
OUTLOOK...
TUESDAY NIGHT...MVFR OR LOWER AT TIMES WITH SHOWERS AND
THUNDERSTORMS. THERE COULD BE SOME MVFR/IFR LATE DUE TO SOME FOG.
WEDNESDAY...POCKETS OF MVFR CONDITIONS IN THE MORNING, OTHERWISE
VFR.
WEDNESDAY NIGHT THROUGH SATURDAY...VFR.
&&
.MARINE...
SUB-ADVISORY CONDITIONS LOOK TO PERSIST ACROSS OUR WATERS TONIGHT
AND TOMORROW. WEAK COLD FRONT WILL NEAR FROM THE NORTHWEST TONIGHT
AND TOMORROW WHILE A SURFACE LOW PRESSURE RIDES ALONG THE FRONTAL
BOUNDARY. THIS IS NOT EXPECTED TO RAISE WINDS OR SEAS SIGNIFICANTLY
BUT WILL PRODUCE WIDESPREAD SHOWERS AND THUNDERSTORMS. WINDS WILL
SLOWLY BACK TOWARDS THE EAST-SOUTHEAST TONIGHT AHEAD OF THE FRONT.
OUTLOOK...
RIGHT NOW WE ARE NOT LOOKING AT SCA CONDITIONS TO OCCUR THROUGH
SATURDAY. HOWEVER, THE NORTHEAST FETCH LATE WEDNESDAY INTO
WEDNESDAY NIGHT AND EARLY THURSDAY WILL BRING SEAS UP TO THE 4
FOOT RANGE, SO THIS WILL CONTINUE TO BE MONITORED CLOSELY. WINDS
AND SEAS SUBSIDE AS WE MOVE INTO FRIDAY AND SATURDAY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...SZATKOWSKI
NEAR TERM...O`HARA
SHORT TERM...HEAVENER
LONG TERM...SZATKOWSKI
AVIATION...SZATKOWSKI/HEAVENER/O`HARA
MARINE...SZATKOWSKI/HEAVENER
000
FXUS61 KPHI 172340
AFDPHI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
740 PM EDT MON JUN 17 2013
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL CONTINUE TO MOVE NORTHEAST THROUGH THE
SAINT LAWRENCE VALLEY TONIGHT. ITS ASSOCIATED COLD FRONT SHOULD
ARRIVE TUESDAY OR TUESDAY NIGHT WITH A WEAK LOW PRESSURE SYSTEM
FORMING ALONG IT. A HIGH PRESSURE SYSTEM WILL THEN BUILD INTO THE
NORTHEAST THE LATTER HALF OF THE WORK WEEK BEFORE SHIFTING
OFFSHORE ON SATURDAY. A WARM FRONT IS FORECAST TO MOVE THROUGH THE
FORECAST AREA ON SUNDAY AND NORTHWARD INTO NEW ENGLAND ON MONDAY.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
A WEAK SURFACE TROUGH WELL AHEAD OF THE SLOW APPROACHING COLD FRONT,
TO OUR NORTHWEST, CONTINUES TO TOUCH OFF WIDELY SCATTERED SHOWERS
WITH EMBEDDED CONVECTION. MUCH OF THE ACTIVITY HAS MOVES ACROSS
SRN NJ ATTM. GUSTY WINDS AND (MOSTLY) SMALL HAIL HAVE ACCOMPANIED
THE CONVECTION. A FLOOD WARNING HAS BEEN ISSUED FOR THE CHRISTINA
RIVER WITH THE HEAVY RAINFALL THAT OCCURRED THERE EARLIER.
THE TROUGH WILL CONTINUE TO SHIFT EASTWARD THROUGH THE EVENING HOURS
AND THESE STORMS SHOULD BE COMING TO AN END OVER THE NEXT COUPLE OF
HOURS. ANOTHER FRONTAL BOUNDARY ACROSS THE GREAT LAKES WILL CONTINUE
TO SLIDE TOWARDS THE EAST-SOUTHEAST THROUGH THE OVERNIGHT HOURS BUT
BEGINS TO LOSE SOME STEAM AS IT BECOMES MORE PARALLEL TO THE
MID-LEVEL FLOW. DECIDED TO KEEP CHANCE POPS IN FOR THIS EVENING AND
A PART OF THE LATE NIGHT JUST ABOUT EVERYWHERE WITH THIS SECOND BOUNDARY.
TEMPERATURES TONIGHT SHOULD BE A COUPLE DEGREES COOLER THAN THIS
MORNING WITH LESS CLOUD COVER IN PLACE AND LIGHT/CALM WINDS. A BASIC
BLEND OF THE MET/MAV WAS USED.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
FRONTAL BOUNDARY WILL CONTINUE TO SLOWLY SAG ACROSS THE REGION
TOMORROW AND AGAIN TOUCH OFF SHOWERS AND POSSIBLY THUNDERSTORMS BY
THE LATE MORNING/EARLY AFTERNOON TIME-FRAME. A WEAK SURFACE WAVE WILL
MOVE ALONG THE FRONT WHICH HELPS WITH LARGER SCALE LIFT IN A
MARGINALLY UNSTABLE ATMOSPHERE...MORE CLOUD COVER TOMORROW THAN
TODAY. STILL NOT QUITE SURE HOW MUCH SURFACE BASED INSTABILITY CAN
BE REALIZED TOMORROW.
THE FLOW ALOFT, WHICH ONCE WAS STRONG, CONTINUES TO WEAKEN ON
TUESDAY SO ANY STORMS THAT DO INITIATE ALONG THE FRONTAL BOUNDARY
ALLOWING FOR A MUCH SLOWER STORM MOTION. PWATS WILL STILL BE FAIRLY
HIGH SO ANY SHOWER/THUNDERSTORM COULD PRODUCE A HEAVY DOWNPOUR IN A
SHORT TIME PERIOD.
TEMPERATURES TOMORROW SHOULD BE A COUPLE OF DEGREES COOLER THAN
TODAY WITH HIGHS IN THE LOW TO MID-80S.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
TIME PERIOD BEGINS WITH COLD FRONTAL BOUNDARY WORKING TO PUSH
THROUGH THE AREA. COLD FRONTAL MOVEMENT STILL LOOKS SLOWER THAN
IT DID SEVERAL DAYS AGO, SO RETAINED THE CHANCE POPS FOR
BOTH TUE NIGHT AND WED, WITH THE HIGHER POPS ON WEDNESDAY CLOSER
TO THE COAST. LOOKED AT BLEND OF MAV/MET ON TUE NIGHT/WEDNESDAY
FOR TEMPERATURES.
HIGH PRESSURE PUSHES INTO THE REGION FOR THE THURSDAY THROUGH
SATURDAY TIME-FRAME, WITH TEMPERATURES RUNNING SLIGHTLY BELOW
NORMAL AND DRY CONDITIONS.
WARM FRONTAL BOUNDARY APPROACH ON SUNDAY BRINGS NEXT POTENTIAL
PRECIPITATION AND BOTH TEMPS AND POPS ON SUNDAY AND MONDAY
FOLLOWED WPC GUIDANCE CLOSELY.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
TONIGHT...THE CONVECTION ACROSS SRN NJ WILL END IN A FEW HOURS.
MOSTLY VFR INTO THE EVENING...THEN AREAS OF FOG MAY DEVELOP WITH
LOWER VSBYS EXPECTED. WINDS WILL BECOME LIGHT VARIABLE OR CALM
OVERNIGHT.
TUESDAY...MVFR POSSIBLY EARLY IN THE MORNING WITH FOG ACROSS A
MAJORITY OF OUR TERMINALS, THEN VFR. THE LIGHT VARIABLE/CALM WINDS
WILL BEGIN TO PICK UP BY LATE MORNING AND BE MORE SOUTHEASTERLY AS A
LOW PRESSURE SYSTEM MAKES ITS WAY ALONG THE FRONTAL BOUNDARY ACROSS
OUR AREA. THIS WILL PROVIDE ANOTHER CHANCE AT SHOWERS AND
THUNDERSTORMS WITH MVFR RESTRICTIONS.
OUTLOOK...
TUESDAY NIGHT...MVFR OR LOWER AT TIMES WITH SHOWERS AND
THUNDERSTORMS. THERE COULD BE SOME MVFR/IFR LATE DUE TO SOME FOG.
WEDNESDAY...POCKETS OF MVFR CONDITIONS IN THE MORNING, OTHERWISE
VFR.
WEDNESDAY NIGHT THROUGH SATURDAY...VFR.
&&
.MARINE...
SUB-ADVISORY CONDITIONS LOOK TO PERSIST ACROSS OUR WATERS TONIGHT
AND TOMORROW. WEAK COLD FRONT WILL NEAR FROM THE NORTHWEST TONIGHT
AND TOMORROW WHILE A SURFACE LOW PRESSURE RIDES ALONG THE FRONTAL
BOUNDARY. THIS IS NOT EXPECTED TO RAISE WINDS OR SEAS SIGNIFICANTLY
BUT WILL PRODUCE WIDESPREAD SHOWERS AND THUNDERSTORMS. WINDS WILL
SLOWLY BACK TOWARDS THE EAST-SOUTHEAST TONIGHT AHEAD OF THE FRONT.
OUTLOOK...
RIGHT NOW WE ARE NOT LOOKING AT SCA CONDITIONS TO OCCUR THROUGH
SATURDAY. HOWEVER, THE NORTHEAST FETCH LATE WEDNESDAY INTO
WEDNESDAY NIGHT AND EARLY THURSDAY WILL BRING SEAS UP TO THE 4
FOOT RANGE, SO THIS WILL CONTINUE TO BE MONITORED CLOSELY. WINDS
AND SEAS SUBSIDE AS WE MOVE INTO FRIDAY AND SATURDAY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...SZATKOWSKI
NEAR TERM...O`HARA
SHORT TERM...HEAVENER
LONG TERM...SZATKOWSKI
AVIATION...SZATKOWSKI/HEAVENER/O`HARA
MARINE...SZATKOWSKI/HEAVENER
000
FXUS61 KPHI 171948
AFDPHI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
348 PM EDT MON JUN 17 2013
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL CONTINUE TO MOVE NORTHEAST THROUGH THE
SAINT LAWRENCE VALLEY TONIGHT. ITS ASSOCIATED COLD FRONT SHOULD
ARRIVE TUESDAY OR TUESDAY NIGHT WITH A WEAK LOW PRESSURE SYSTEM
FORMING ALONG IT. A HIGH PRESSURE SYSTEM WILL THEN BUILD INTO THE
NORTHEAST THE LATTER HALF OF THE WORK WEEK BEFORE SHIFTING
OFFSHORE ON SATURDAY. A WARM FRONT IS FORECAST TO MOVE THROUGH THE
FORECAST AREA ON SUNDAY AND NORTHWARD INTO NEW ENGLAND ON MONDAY.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
A WEAK SURFACE TROUGH WELL AHEAD OF THE SLOW APPROACHING COLD FRONT,
TO OUR NORTHWEST, HAS/IS TOUCHING OFF WIDELY SCATTERED SHOWERS WITH
EMBEDDED CONVECTION. FOR THE MOST PART THIS PRE-FRONTAL TROUGH IS
NOT PROVIDING A LOT OF LIFT TO GENERATE WIDESPREAD CONVECTION BUT
SOME OF THE STORMS THAT DO FORM ARE TAPPING INTO A DECENT AMOUNT OF
SURFACE BASED INSTABILITY AND FORMING STRONGER UPDRAFTS. DID NOT ADD
ENHANCED WORDING TO THE GRIDS GIVEN THE SPATIAL COVERAGE IS LOW BUT
SOME OF THESE STORMS ARE CAPABLE OF PRODUCING STRONG, POSSIBLY
DAMAGING WINDS. HAIL LOOKS LESS LIKELY WITH THE FREEZING LEVEL
AROUND 14KFT ACROSS MOST OF THE AREA AND WITH THE DRIER SUB-CLOUD
LAYER.
THE TROUGH WILL CONTINUE TO SHIFT EASTWARD THROUGH THE EVENING HOURS
AND THESE STORMS SHOULD BE COMING TO AN END OVER THE NEXT COUPLE OF
HOURS. ANOTHER FRONTAL BOUNDARY ACROSS THE GREAT LAKES WILL CONTINUE
TO SLIDE TOWARDS THE EAST-SOUTHEAST THROUGH THE OVERNIGHT HOURS BUT
BEGINS TO LOSE SOME STEAM AS IT BECOMES MORE PARALLEL TO THE
MID-LEVEL FLOW. DECIDED TO KEEP CHANCE POPS IN FOR THIS EVENING AND
A PART OF THE LATE NIGHT JUST ABOUT EVERYWHERE WITH THIS SECOND BOUNDARY.
TEMPERATURES TONIGHT SHOULD BE A COUPLE DEGREES COOLER THAN THIS
MORNING WITH LESS CLOUD COVER IN PLACE AND LIGHT/CALM WINDS. A BASIC
BLEND OF THE MET/MAV WAS USED.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
FRONTAL BOUNDARY WILL CONTINUE TO SLOWLY SAG ACROSS THE REGION
TOMORROW AND AGAIN TOUCH OFF SHOWERS AND POSSIBLY THUNDERSTORMS BY
THE LATE MORNING/EARLY AFTERNOON TIMEFRAME. A WEAK SURFACE WAVE WILL
MOVE ALONG THE FRONT WHICH HELPS WITH LARGER SCALE LIFT IN A
MARGINALLY UNSTABLE ATMOSPHERE...MORE CLOUD COVER TOMORROW THAN
TODAY. STILL NOT QUITE SURE HOW MUCH SURFACE BASED INSTABILITY CAN
BE REALIZED TOMORROW.
THE FLOW ALOFT, WHICH ONCE WAS STRONG, CONTINUES TO WEAKEN ON
TUESDAY SO ANY STORMS THAT DO INITIATE ALONG THE FRONTAL BOUNDARY
ALLOWING FOR A MUCH SLOWER STORM MOTION. PWATS WILL STILL BE FAIRLY
HIGH SO ANY SHOWER/THUNDERSTORM COULD PRODUCE A HEAVY DOWNPOUR IN A
SHORT TIME PERIOD.
TEMPERATURES TOMORROW SHOULD BE A COUPLE OF DEGREES COOLER THAN
TODAY WITH HIGHS IN THE LOW TO MID-80S.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
TIME PERIOD BEGINS WITH COLD FRONTAL BOUNDARY WORKING TO PUSH
THROUGH THE AREA. COLD FRONTAL MOVEMENT STILL LOOKS SLOWER THAN
IT DID SEVERAL DAYS AGO, SO RETAINED THE CHANCE POPS FOR
BOTH TUE NIGHT AND WED, WITH THE HIGHER POPS ON WEDNESDAY CLOSER
TO THE COAST. LOOKED AT BLEND OF MAV/MET ON TUE NIGHT/WEDNESDAY
FOR TEMPERATURES.
HIGH PRESSURE PUSHES INTO THE REGION FOR THE THURSDAY THROUGH
SATURDAY TIMEFRAME, WITH TEMPERATURES RUNNING SLIGHTLY BELOW
NORMAL AND DRY CONDITIONS.
WARM FRONTAL BOUNDARY APPROACH ON SUNDAY BRINGS NEXT POTENTIAL
PRECIPITATION AND BOTH TEMPS AND POPS ON SUNDAY AND MONDAY
FOLLOWED WPC GUIDANCE CLOSELY.
&&
.AVIATION /19Z MONDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
THIS EVENING - TONIGHT...MOSTLY VFR. WILL CONTINUE WITH OUR LIGHT
SOUTHWEST WINDS THROUGH THE EVENING HOURS. A WEAK SURFACE TROUGH IS
CURRENTLY PUSHING IN FROM THE NORTHWEST AND IS INITIATING SHOWERS
WITH EMBEDDED THUNDERSTORMS. DECIDED IT WOULD BE BEST, GIVEN THE
CURRENT WIDELY SCATTERED ACTIVITY TO PLACE -TSRA TEMPO GROUPS IN FOR
A COUPLE HOURS EARLY IN THE CYCLE. BEHIND THIS INITIAL LINE THE AIR
LOOKS TOO DRY TO CONTINUE WITH THE SHOWER ACTIVITY SO THERE LOOKS TO
BE A DECENT LULL BETWEEN PRECIPITATION EVENTS.
ANOTHER AREA WE ARE WATCHING IS A COLD FRONT PRESSING IN FROM THE
NORTHWEST MOVING ACROSS THE GREAT LAKES. MORE SHOWERS/THUNDERSTORMS
ARE ERUPTING ALONG THIS LINE AS WE SPEAK AND IF THEY WERE TO HOLD
TOGETHER THEY WOULD BEGIN TO IMPACT RDG/ABE BY LATE THIS EVENING.
CONFIDENCE WAS NOT HIGH ON THESE SHOWERS/STORMS MAKING IT INTO OUR
TERMINALS TONIGHT SO THEY WERE HELD OUT FOR THE MOMENT.
TUESDAY...MVFR POSSIBLY EARLY IN THE MORNING WITH FOG ACROSS A
MAJORITY OF OUR TERMINALS, THEN VFR. THE LIGHT VARIABLE/CALM WINDS
WILL BEGIN TO PICK UP BY LATE MORNING AND BE MORE SOUTHEASTERLY AS A
LOW PRESSURE SYSTEM MAKES ITS WAY ALONG THE FRONTAL BOUNDARY ACROSS
OUR AREA. THIS WILL PROVIDE ANOTHER CHANCE AT SHOWERS AND
THUNDERSTORMS WITH MVFR RESTRICTIONS.
OUTLOOK...
TUESDAY NIGHT...MVFR OR LOWER AT TIMES WITH SHOWERS AND
THUNDERSTORMS. THERE COULD BE SOME MVFR/IFR LATE DUE TO SOME FOG.
WEDNESDAY...POCKETS OF MVFR CONDITIONS IN THE MORNING, OTHERWISE
VFR.
WEDNESDAY NIGHT THROUGH SATURDAY...VFR.
&&
.MARINE...
SUB-ADVISORY CONDITIONS LOOK TO PERSIST ACROSS OUR WATERS TONIGHT
AND TOMORROW. WEAK COLD FRONT WILL NEAR FROM THE NORTHWEST TONIGHT
AND TOMORROW WHILE A SURFACE LOW PRESSURE RIDES ALONG THE FRONTAL
BOUNDARY. THIS IS NOT EXPECTED TO RAISE WINDS OR SEAS SIGNIFICANTLY
BUT WILL PRODUCE WIDESPREAD SHOWERS AND THUNDERSTORMS. WINDS WILL
SLOWLY BACK TOWARDS THE EAST-SOUTHEAST TONIGHT AHEAD OF THE FRONT.
OUTLOOK...
RIGHT NOW WE ARE NOT LOOKING AT SCA CONDITIONS TO OCCUR THROUGH
SATURDAY. HOWEVER, THE NORTHEAST FETCH LATE WEDNESDAY INTO
WEDNESDAY NIGHT AND EARLY THURSDAY WILL BRING SEAS UP TO THE 4
FOOT RANGE, SO THIS WILL CONTINUE TO BE MONITORED CLOSELY. WINDS
AND SEAS SUBSIDE AS WE MOVE INTO FRIDAY AND SATURDAY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...SZATKOWSKI
NEAR TERM...HEAVENER
SHORT TERM...HEAVENER
LONG TERM...SZATKOWSKI
AVIATION...SZATKOWSKI/HEAVENER
MARINE...SZATKOWSKI/HEAVENER
000
FXUS61 KPHI 171801
AFDPHI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
201 PM EDT MON JUN 17 2013
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL CONTINUE TO MOVE NORTHEAST THROUGH THE
SAINT LAWRENCE VALLEY TODAY AND TONIGHT. ITS FIRST WEAKENING COLD
FRONT SHOULD CLEAR THE FORECAST AREA THIS MORNING. THEN ITS
SECONDARY COLD FRONT SHOULD ARRIVE TUESDAY OR TUESDAY NIGHT WITH A
WEAK LOW PRESSURE SYSTEM FORMING ALONG IT. A HIGH PRESSURE SYSTEM
WILL THEN BUILD INTO THE NORTHEAST THE LATTER HALF OF THE WORK WEEK
BEFORE SHIFTING OFFSHORE ON SATURDAY. A WARM FRONT IS FORECAST TO
MOVE THROUGH THE FORECAST AREA ON SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NOT MUCH IN THE WAY OF CHANGE THIS MORNING BUT DID ADJUST THE POPS
SOMEWHAT TO TRY AND BETTER TIME ANY SHOWERY ACTIVITY THIS MORNING.
THE CURRENT ACTIVITY SOUTH OF LATROBE AND JOHNSTOWN PENNSYLVANIA
IS TIED TO A WEAK SHORTWAVE OR VORT LOBE. A FEW OF THE HI-RES
MODELS SHOW THIS ACTIVITY TRACKING JUST TO OUR SOUTHEAST WITHIN
THE FAST WESTERLY MID-LEVEL FLOW BUT IT ALSO DRIES THEM OUT WITH DOWNSLOPING
TAKING PLACE.
THERE IS MUCH BETTER INSTABILITY TODAY COMPARED TO SUNDAY THOUGH
WE ARE A TOUCH DRIER THROUGHOUT THE COLUMN WITH A FAIRLY LARGE DRY
POCKET IN THE MID-LEVELS. THE INHIBITING FACTOR FOR TODAY ARE THE
LACK OF BETTER WIND PROFILES. SHEAR IS LACKING WITH LESS THAN
25KTS WITHIN THE 0-6KM LAYER SO BETTER ORGANIZED CONVECTIVE LOOKS
OUT OF THE QUESTION, AT LEAST ACROSS THE SOUTHERN HALF OF OUR CWA.
FURTHER NORTH THERE ARE BETTER JET DYNAMICS COMBINED WITH STRONGER
UNI-DIRECTIONAL WINDS AND A SURFACE FOCUS (ANOTHER WEAK COLD
FRONT) SO ONCE WE GET THINGS GOING THIS AFTERNOON WE COULD SEE
BETTER CLUSTERING OF CONVECTION.
OVERALL THE MAJORITY OF THE CWA SHOULD BE PRECIP FREE TODAY.
THE MAJORITY OF TEMPS ARE FORECAST TO BE IN THE MID 80S. THE
EXCEPTION OF COURSE WILL BE ACROSS OUR NORTHWEST ELEVATIONS AND THE
COAST.
WEST TO SOUTHWEST WINDS WILL BE IN THE 5 TO 10 MPH RANGE, MAYBE UP
TO 15 MPH THIS AFTERNOON AT TIMES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
THIS PERIOD STARTS WITH THE NORTHERN FRONT POISED TO ENTER THE
FORECAST AREA WHILE THE MID-LEVELS REMAIN ZONAL. POPS EXPAND AND
INCREASE A BIT IN RESPONSE ACROSS THE NORTHERN 1/3 OF THE CWA.
ACROSS THE SOUTHERN 1/3 OF THE CWA, POPS REMAIN IN PLACE WITH THE
SOUTHERN FRONT JUST TO OUR SOUTH.
SMALL POPS FILL IN THE MIDDLE 1/3 OF THE CWA AFTER 06Z AS THE
NORTHERN FRONT CONTINUES TO DRIFT SOUTH. ONCE AGAIN GFS MAV POPS ARE
FAVORED.
TEMPS WILL FALL BACK IN TO 50S ACROSS THE FAR NORTHWEST AND REMAIN
IN THE 60S ELSEWHERE. SOUTHERN DELAWARE WILL REMAIN CLOSE TO 70.
WINDS WILL BE LIGHT OUT OF THE SOUTHWEST.
&&
.LONG TERM /TUESDAY THROUGH MONDAY/...
THE WRF-NMMB INITIALIZATION LOOKED SLIGHTLY BETTER OVERALL AND THE
SOUNDING PROBLEMS AT ALB AND CHH DID NOT APPEAR TO HAVE AN IMPACT.
OVERALL THE MODELING CONSENSUS WAS BETTER THAN LAST NIGHT WITH A
SLIGHT SLOWING TREND WITH THE SECONDARY COLD FRONT. WITH THE OP GFS
AND WRF-NMMB VERY SIMILAR TO EACH OTHER`S ENSEMBLE MEAN, CONFIDENCE
ABOUT THE TIMING IS INCREASING FOR THE HIEST POPS (NOON-MIDN ON
TUE), UNFORTUNATELY, THESE ARE CRIS-CROSSING FCST PERIODS, SO OUR
POPS ARE MORE OF A REFLECTION TO THE UNCERTAINTY OF WHICH FCST
PERIOD, THAN THE OVERALL PROBABILITIES WHICH APPEAR LIKELY.
AS FOR THE DETAILS, THIS IS A TYPICAL SPLIT WE FIND IN OUR CWA WITH
THE FCST HIGHEST CAPES (WRF SOUNDING LLVL DEW POINTS LOOK MORE
REASONABLE THAN THE GFS) SOUTH AND THE BEST WIND FIELD AND FORCING
NORTH AS WELL AS THE ENTRANCE REGION TO THE 250MB JET. THE
FORECAST CONVECTIVE TEMPS ARE EXPECTED TO BE REACHED, BUT NOT TIL
THE AFTERNOON. GIVEN THE EVER SO SLIGHT SLOWING TREND BY THE
MODELS, THE MORNING POP MENTION MAY VERY WELL BE TOO FAST AND EVEN
THE POPS SOUTH MAY HAVE TO RELY ON SEA/BAY BREEZES TO INITIATE.
REGARDLESS WITH ADDITIONAL HEATING EXPECTED AND FCST CAPES GETTING
TO AROUND 1000J, DECENT FCST BULK SHEAR (WIND BELOW 700MB
ADMITTEDLY WEAK) AND DCAPE APPROACHING 1000J WE WILL HAVE TO WATCH
FOR THE FORMATION OF ROBUST THUNDER. SPC SEE TEXT LOOKS GOOD AT
THIS POINT. SOME MESOSCALE MODELS ARE PREDICTING A SQUALL LINE
MOVING THROUGH THE NORTHERN HALF OF OUR CWA BY LATE IN THE DAY
TUESDAY. AS ANYONE THAT FOLLOWS THESE MODELS, THEY CAN BE
FRIGHTENINGLY ACCURATE, BUT THEY HAVE TO GET THE IGNITION SEQUENCE
CLOSE. ALBEIT WITH BETTER LOOKING TIMING, WE DID UP THE POPS AND
WITH PWATS FCST TO STILL REACH 1.5 INCHES, HEAVY DOWNPOURS NOT OUT
OF THE QUESTION EITHER. BECAUSE OF THE SLOWER FRONTAL TIMING, STAT
GUIDANCE HAS BECOME HOTTER WITH MAX TEMPS. NOT GOING THAT HOT YET
BASED ON RECENT WET CONDITIONS, BUT WE BUMPED MAX TEMPS UP BY
AROUND 5F.
WE NUDGED THE AXIS OF HIGHEST POPS SOUTH ON TUESDAY EVENING AND THEN
LOWER POPS OVERNIGHT. USING A GFS AND ECMWF COMPROMISE, WE KEPT THE
MENTION OF THUNDER THRUT ON TUESDAY EVENING AND IN THE SOUTHERN
PART OF OUR CWA THRU THE NIGHT. MIN TEMPS WERE ALSO BUMPED UPWARD
BECAUSE OF THE SLOWER TIMING.
I GUESS IT SHOULD HAVE COME AS NO SURPRISE AS WE GET CLOSER TO
ASTRONOMICAL SUMMER THAT THE COLD FRONTS ARE STRUGGLING TO MOVE
SOUTHWARD. WHILE THE WAVE ON THE FRONT IS FORECAST TO BE WEAKER, THE
LATEST WRINKLE ABOUT EXTENDING POPS INTO WEDNESDAY COMES FROM A
SHORT WAVE TROF INTERACTING WITH A BANKING AND DEVELOPING UPSLOPE
FLOW. WITH THE OCEAN STILL RELATIVELY COOL, THE STABILIZING
INFLUENCE OF THE ONSHORE FLOW IS DEFLECTING SFC (ALOFT TOO) BASED
INSTABILITY WEST OF OUR CWA. WANT TO SEE WHERE THIS GOES BEFORE WE
GET MORE DOUR, BUT FOR NOW WE INTRODUCED LOW POPS. THE ONSHORE
FLOW COUPLED WITH THE 500MB TROF NOT THROUGH SHOULD HELP
GENERATE/PERPETUATE CLOUDINESS, SO WE DID KEEP THE IDEA OF A
CHILLY DAY ALONG THE COAST AND KNOCKED DOWN MAX TEMPS ABOUT 1OF
FROM TUESDAY.
NOT GOING THERE WITH THE WRF-NMMB FOGGING US IN ON WEDNESDAY
NIGHT. THE AIR MASS IS FCST TO BE DRYING, SO HAVE TO SEE THE SFC
HIGH STRUGGLE MORE THAN CURRENTLY PROGGED. DRIER AIR AROUND THE
SFC HIGH EVEN IF WEAK ONSHORE FLOW WILL MAKE FOR A SUNNIER DAY ON
THURSDAY WITH MAX TEMPS STILL SLIGHTLY BELOW NORMAL.
NO BIG CHANGES BEYOND THAT. A DISSIPATING COLD FRONT IS NOT
FORECAST TO BRING ANY PCPN OUR WAY ON FRIDAY AND MIGHT EVEN IN ITS
DEMISE HELP SLOW THE ARRIVAL OF MORE HUMID AIR. THE WARM FRONTAL
PASSAGE (AND POPS) HAS BEEN PUSHED BACK TO LATE SATURDAY AND
SUNDAY. REGARDLESS BY THE FIRST WEEKEND OF ASTRONOMICAL SUMMER,
TEMPERATURES SHOULD BE AT OR ABOVE AVERAGE.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
THIS EVENING - TONIGHT...MOSTLY VFR. WILL CONTINUE WITH OUR LIGHT
SOUTHWEST WINDS THROUGH THE EVENING HOURS. A WEAK SURFACE TROUGH IS
CURRENTLY PUSHING IN FROM THE NORTHWEST AND IS INITIATING SHOWERS
WITH EMBEDDED THUNDERSTORMS. DECIDED IT WOULD BE BEST, GIVEN THE
CURRENT WIDELY SCATTERED ACTIVITY TO PLACE -TSRA TEMPO GROUPS IN FOR
A COUPLE HOURS EARLY IN THE CYCLE. BEHIND THIS INITIAL LINE THE AIR
LOOKS TOO DRY TO CONTINUE WITH THE SHOWER ACTIVITY SO THERE LOOKS TO
BE A DECENT LULL BETWEEN PRECIPITATION EVENTS.
ANOTHER AREA WE ARE WATCHING IS A COLD FRONT PRESSING IN FROM THE
NORTHWEST MOVING ACROSS THE GREAT LAKES. MORE SHOWERS/THUNDERSTORMS
ARE ERUPTING ALONG THIS LINE AS WE SPEAK AND IF THEY WERE TO HOLD
TOGETHER THEY WOULD BEGIN TO IMPACT RDG/ABE BY LATE THIS EVENING.
CONFIDENCE WAS NOT HIGH ON THESE SHOWERS/STORMS MAKING IT INTO OUR
TERMINALS TONIGHT SO THEY WERE HELD OUT FOR THE MOMENT.
TUESDAY...MVFR POSSIBLY EARLY IN THE MORNING WITH FOG ACROSS A
MAJORITY OF OUR TERMINALS, THEN VFR. THE LIGHT VARIABLE/CALM WINDS
WILL BEGIN TO PICK UP BY LATE MORNING AND BE MORE SOUTHEASTERLY AS A
LOW PRESSURE SYSTEM MAKES ITS WAY ALONG THE FRONTAL BOUNDARY ACROSS
OUR AREA. THIS WILL PROVIDE ANOTHER CHANCE AT SHOWERS AND
THUNDERSTORMS WITH MVFR RESTRICTIONS.
OUTLOOK...
TUESDAY NIGHT...MVFR OR LOWER AT TIMES WITH SHOWERS AND
THUNDERSTORMS. THERE COULD BE SOME MVFR/IFR LATE DUE TO SOME FOG.
WEDNESDAY...POCKETS OF MVFR CONDITIONS IN THE MORNING, OTHERWISE
VFR.
WEDNESDAY NIGHT THROUGH FRIDAY...VFR.
&&
.MARINE...
NO HEADLINES WILL BE ISSUED THIS MORNING FOR AREA WATERS.
SOUTHWEST WINDS WILL PEAK IN THE 10 TO 15 MPH RANGE THIS AFTERNOON.
OCEAN WAVES WILL BE IN THE 2 TO 4 FOOT RANGE WITH 1 TO 2 ON DELAWARE
BAY.
NOT MUCH CHANGE TONIGHT EXCEPT WE`LL THROW SOME 20 KT GUSTS INTO THE
FORECAST WITH THE ARRIVAL OF COLD FRONT FROM THE NORTH.
SMALL POPS REMAIN IN THE FORECAST ACROSS THE SOUTH TODAY AND EXPAND
TO INCLUDE THE NORTH TONIGHT.
OUTLOOK...
RIGHT NOW WE ARE NOT OUTLOOKING SCA CONDITIONS TO OCCUR THROUGH
FRIDAY. THE LOW PRESSURE SYSTEM ON THE FRONTAL BOUNDARY IS FORECAST
TO BE WEAKER THAN LAST NIGHT. HOWEVER, THE WAY THE HIGH PRESSURE
SYSTEM IS FORECAST TO BUILD INTO THE AREA WATERS IS NOW BRINGING
MORE OF A NORTHEAST TO EAST FETCH WEDNESDAY INTO THURSDAY. WE WILL
SEE IF THIS NEW DEVELOPMENT HAS STAYING POWER AND WHETHER OR NOT THE
ONSHORE FLOW AND SWELLS GET ENHANCED ENOUGH TO POSSIBLY REACH SCA
CONDITIONS. THEN THE LIKELIHOOD OF SUB SMALL CRAFT ADVISORY
CONDITIONS INCREASES ON FRIDAY AS THE SFC HIGH SETTLES NEARBY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...GIGI/GORSE
NEAR TERM...HEAVENER/KRUZDLO
SHORT TERM...KRUZDLO
LONG TERM...GIGI
AVIATION...GIGI/GORSE/HEAVENER
MARINE...GIGI/KRUZDLO
000
FXUS61 KPHI 171343
AFDPHI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
943 AM EDT MON JUN 17 2013
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL CONTINUE TO MOVE NORTHEAST THROUGH THE
SAINT LAWRENCE VALLEY TODAY AND TONIGHT. ITS FIRST WEAKENING COLD
FRONT SHOULD CLEAR THE FORECAST AREA THIS MORNING. THEN ITS
SECONDARY COLD FRONT SHOULD ARRIVE TUESDAY OR TUESDAY NIGHT WITH A
WEAK LOW PRESSURE SYSTEM FORMING ALONG IT. A HIGH PRESSURE SYSTEM
WILL THEN BUILD INTO THE NORTHEAST THE LATTER HALF OF THE WORK WEEK
BEFORE SHIFTING OFFSHORE ON SATURDAY. A WARM FRONT IS FORECAST TO
MOVE THROUGH THE FORECAST AREA ON SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NOT MUCH IN THE WAY OF CHANGE THIS MORNING BUT DID ADJUST THE POPS
SOMEWHAT TO TRY AND BETTER TIME ANY SHOWERY ACTIVITY THIS MORNING.
THE CURRENT ACTIVITY SOUTH OF LATROBE AND JOHNSTOWN PENNSYLVANIA
IS TIED TO A WEAK SHORTWAVE OR VORT LOBE. A FEW OF THE HI-RES
MODELS SHOW THIS ACTIVITY TRACKING JUST TO OUR SOUTHEAST WITHIN
THE FAST WESTERLY MID-LEVEL FLOW BUT IT ALSO DRIES THEM OUT WITH DOWNSLOPING
TAKING PLACE.
THERE IS MUCH BETTER INSTABILITY TODAY COMPARED TO SUNDAY THOUGH
WE ARE A TOUCH DRIER THROUGHOUT THE COLUMN WITH A FAIRLY LARGE DRY
POCKET IN THE MID-LEVELS. THE INHIBITING FACTOR FOR TODAY ARE THE
LACK OF BETTER WIND PROFILES. SHEAR IS LACKING WITH LESS THAN
25KTS WITHIN THE 0-6KM LAYER SO BETTER ORGANIZED CONVECTIVE LOOKS
OUT OF THE QUESTION, AT LEAST ACROSS THE SOUTHERN HALF OF OUR CWA.
FURTHER NORTH THERE ARE BETTER JET DYNAMICS COMBINED WITH STRONGER
UNI-DIRECTIONAL WINDS AND A SURFACE FOCUS (ANOTHER WEAK COLD
FRONT) SO ONCE WE GET THINGS GOING THIS AFTERNOON WE COULD SEE
BETTER CLUSTERING OF CONVECTION.
OVERALL THE MAJORITY OF THE CWA SHOULD BE PRECIP FREE TODAY.
THE MAJORITY OF TEMPS ARE FORECAST TO BE IN THE MID 80S. THE
EXCEPTION OF COURSE WILL BE ACROSS OUR NORTHWEST ELEVATIONS AND THE
COAST.
WEST TO SOUTHWEST WINDS WILL BE IN THE 5 TO 10 MPH RANGE, MAYBE UP
TO 15 MPH THIS AFTERNOON AT TIMES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
THIS PERIOD STARTS WITH THE NORTHERN FRONT POISED TO ENTER THE
FORECAST AREA WHILE THE MID-LEVELS REMAIN ZONAL. POPS EXPAND AND
INCREASE A BIT IN RESPONSE ACROSS THE NORTHERN 1/3 OF THE CWA.
ACROSS THE SOUTHERN 1/3 OF THE CWA, POPS REMAIN IN PLACE WITH THE
SOUTHERN FRONT JUST TO OUR SOUTH.
SMALL POPS FILL IN THE MIDDLE 1/3 OF THE CWA AFTER 06Z AS THE
NORTHERN FRONT CONTINUES TO DRIFT SOUTH. ONCE AGAIN GFS MAV POPS ARE
FAVORED.
TEMPS WILL FALL BACK IN TO 50S ACROSS THE FAR NORTHWEST AND REMAIN
IN THE 60S ELSEWHERE. SOUTHERN DELAWARE WILL REMAIN CLOSE TO 70.
WINDS WILL BE LIGHT OUT OF THE SOUTHWEST.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
THE WRF-NMMB INITIALIZATION LOOKED SLIGHTLY BETTER OVERALL AND THE
SOUNDING PROBLEMS AT ALB AND CHH DID NOT APPEAR TO HAVE AN IMPACT.
OVERALL THE MODELING CONSENSUS WAS BETTER THAN LAST NIGHT WITH A
SLIGHT SLOWING TREND WITH THE SECONDARY COLD FRONT. WITH THE OP GFS
AND WRF-NMMB VERY SIMILAR TO EACH OTHER`S ENSEMBLE MEAN, CONFIDENCE
ABOUT THE TIMING IS INCREASING FOR THE HIEST POPS (NOON-MIDN ON
TUE), UNFORTUNATELY, THESE ARE CRIS-CROSSING FCST PERIODS, SO OUR
POPS ARE MORE OF A REFLECTION TO THE UNCERTAINTY OF WHICH FCST
PERIOD, THAN THE OVERALL PROBABILITIES WHICH APPEAR LIKELY.
AS FOR THE DETAILS, THIS IS A TYPICAL SPLIT WE FIND IN OUR CWA WITH
THE FCST HIGHEST CAPES (WRF SOUNDING LLVL DEW POINTS LOOK MORE
REASONABLE THAN THE GFS) SOUTH AND THE BEST WIND FIELD AND FORCING
NORTH AS WELL AS THE ENTRANCE REGION TO THE 250MB JET. THE
FORECAST CONVECTIVE TEMPS ARE EXPECTED TO BE REACHED, BUT NOT TIL
THE AFTERNOON. GIVEN THE EVER SO SLIGHT SLOWING TREND BY THE
MODELS, THE MORNING POP MENTION MAY VERY WELL BE TOO FAST AND EVEN
THE POPS SOUTH MAY HAVE TO RELY ON SEA/BAY BREEZES TO INITIATE.
REGARDLESS WITH ADDITIONAL HEATING EXPECTED AND FCST CAPES GETTING
TO AROUND 1000J, DECENT FCST BULK SHEAR (WIND BELOW 700MB
ADMITTEDLY WEAK) AND DCAPE APPROACHING 1000J WE WILL HAVE TO WATCH
FOR THE FORMATION OF ROBUST THUNDER. SPC SEE TEXT LOOKS GOOD AT
THIS POINT. SOME MESOSCALE MODELS ARE PREDICTING A SQUALL LINE
MOVING THROUGH THE NORTHERN HALF OF OUR CWA BY LATE IN THE DAY
TUESDAY. AS ANYONE THAT FOLLOWS THESE MODELS, THEY CAN BE
FRIGHTENINGLY ACCURATE, BUT THEY HAVE TO GET THE IGNITION SEQUENCE
CLOSE. ALBEIT WITH BETTER LOOKING TIMING, WE DID UP THE POPS AND
WITH PWATS FCST TO STILL REACH 1.5 INCHES, HEAVY DOWNPOURS NOT OUT
OF THE QUESTION EITHER. BECAUSE OF THE SLOWER FRONTAL TIMING, STAT
GUIDANCE HAS BECOME HOTTER WITH MAX TEMPS. NOT GOING THAT HOT YET
BASED ON RECENT WET CONDITIONS, BUT WE BUMPED MAX TEMPS UP BY
AROUND 5F.
WE NUDGED THE AXIS OF HIGHEST POPS SOUTH ON TUESDAY EVENING AND THEN
LOWER POPS OVERNIGHT. USING A GFS AND ECMWF COMPROMISE, WE KEPT THE
MENTION OF THUNDER THRUT ON TUESDAY EVENING AND IN THE SOUTHERN
PART OF OUR CWA THRU THE NIGHT. MIN TEMPS WERE ALSO BUMPED UPWARD
BECAUSE OF THE SLOWER TIMING.
I GUESS IT SHOULD HAVE COME AS NO SURPRISE AS WE GET CLOSER TO
ASTRONOMICAL SUMMER THAT THE COLD FRONTS ARE STRUGGLING TO MOVE
SOUTHWARD. WHILE THE WAVE ON THE FRONT IS FORECAST TO BE WEAKER, THE
LATEST WRINKLE ABOUT EXTENDING POPS INTO WEDNESDAY COMES FROM A
SHORT WAVE TROF INTERACTING WITH A BANKING AND DEVELOPING UPSLOPE
FLOW. WITH THE OCEAN STILL RELATIVELY COOL, THE STABILIZING
INFLUENCE OF THE ONSHORE FLOW IS DEFLECTING SFC (ALOFT TOO) BASED
INSTABILITY WEST OF OUR CWA. WANT TO SEE WHERE THIS GOES BEFORE WE
GET MORE DOUR, BUT FOR NOW WE INTRODUCED LOW POPS. THE ONSHORE
FLOW COUPLED WITH THE 500MB TROF NOT THROUGH SHOULD HELP
GENERATE/PERPETUATE CLOUDINESS, SO WE DID KEEP THE IDEA OF A
CHILLY DAY ALONG THE COAST AND KNOCKED DOWN MAX TEMPS ABOUT 1OF
FROM TUESDAY.
NOT GOING THERE WITH THE WRF-NMMB FOGGING US IN ON WEDNESDAY
NIGHT. THE AIR MASS IS FCST TO BE DRYING, SO HAVE TO SEE THE SFC
HIGH STRUGGLE MORE THAN CURRENTLY PROGGED. DRIER AIR AROUND THE
SFC HIGH EVEN IF WEAK ONSHORE FLOW WILL MAKE FOR A SUNNIER DAY ON
THURSDAY WITH MAX TEMPS STILL SLIGHTLY BELOW NORMAL.
NO BIG CHANGES BEYOND THAT. A DISSIPATING COLD FRONT IS NOT
FORECAST TO BRING ANY PCPN OUR WAY ON FRIDAY AND MIGHT EVEN IN ITS
DEMISE HELP SLOW THE ARRIVAL OF MORE HUMID AIR. THE WARM FRONTAL
PASSAGE (AND POPS) HAS BEEN PUSHED BACK TO LATE SATURDAY AND
SUNDAY. REGARDLESS BY THE FIRST WEEKEND OF ASTRONOMICAL SUMMER,
TEMPERATURES SHOULD BE AT OR ABOVE AVERAGE.
&&
.AVIATION /13Z MONDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
VFR TODAY AND SHOULD REMAIN THAT WAY THROUGH THE PERIOD EXCEPT IN
SHOWERS. FOR NOW, WE`LL HIT KABE IN THE NORTH WITH SOME SHOWERS
AND KILG, KMIV, AND KILG ACROSS THE SOUTH. NOTHING AT THE PHILLY
TERMINALS, TRENTON, OR READING.
WEST TO SOUTHWEST WINDS WILL MAX OUT THIS AFTERNOON AT ABOUT 10 KT
TODAY AND FALL BACK IN THE 5 TO 10 MPH RANGE TONIGHT.
OUTLOOK...
TUESDAY AND TUESDAY NIGHT...MVFR OR LOWER AT TIMES WITH SHOWERS
AND THUNDERSTORMS. THERE COULD BE SOME MVFR/IFR LATE AT NIGHT DUE
TO SOME FOG.
WEDNESDAY...POCKETS OF MVFR CONDITIONS IN THE MORNING, OTHERWISE
VFR.
WEDNESDAY NIGHT THROUGH FRIDAY...VFR.
&&
.MARINE...
NO HEADLINES WILL BE ISSUED THIS MORNING FOR AREA WATERS.
SOUTHWEST WINDS WILL PEAK IN THE 10 TO 15 MPH RANGE THIS AFTERNOON.
OCEAN WAVES WILL BE IN THE 2 TO 4 FOOT RANGE WITH 1 TO 2 ON DELAWARE
BAY.
NOT MUCH CHANGE TONIGHT EXCEPT WE`LL THROW SOME 20 KT GUSTS INTO THE
FORECAST WITH THE ARRIVAL OF COLD FRONT FROM THE NORTH.
SMALL POPS REMAIN IN THE FORECAST ACROSS THE SOUTH TODAY AND EXPAND
TO INCLUDE THE NORTH TONIGHT.
OUTLOOK...
RIGHT NOW WE ARE NOT OUTLOOKING SCA CONDITIONS TO OCCUR THROUGH
FRIDAY. THE LOW PRESSURE SYSTEM ON THE FRONTAL BOUNDARY IS FORECAST
TO BE WEAKER THAN LAST NIGHT. HOWEVER, THE WAY THE HIGH PRESSURE
SYSTEM IS FORECAST TO BUILD INTO THE AREA WATERS IS NOW BRINGING
MORE OF A NORTHEAST TO EAST FETCH WEDNESDAY INTO THURSDAY. WE WILL
SEE IF THIS NEW DEVELOPMENT HAS STAYING POWER AND WHETHER OR NOT THE
ONSHORE FLOW AND SWELLS GET ENHANCED ENOUGH TO POSSIBLY REACH SCA
CONDITIONS. THEN THE LIKELIHOOD OF SUB SMALL CRAFT ADVISORY
CONDITIONS INCREASES ON FRIDAY AS THE SFC HIGH SETTLES NEARBY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...GIGI/GORSE
NEAR TERM...HEAVENER/KRUZDLO
SHORT TERM...KRUZDLO
LONG TERM...GIGI
AVIATION...GIGI/GORSE/HEAVENER/KRUZDLO
MARINE...GIGI/KRUZDLO
000
FXUS61 KPHI 170746
AFDPHI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
346 AM EDT MON JUN 17 2013
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL CONTINUE TO MOVE NORTHEAST THROUGH THE
SAINT LAWRENCE VALLEY TODAY AND TONIGHT. ITS FIRST WEAKENING COLD
FRONT SHOULD CLEAR THE FORECAST AREA THIS MORNING. THEN ITS
SECONDARY COLD FRONT SHOULD ARRIVE TUESDAY OR TUESDAY NIGHT WITH A
WEAK LOW PRESSURE SYSTEM FORMING ALONG IT. A HIGH PRESSURE SYSTEM
WILL THEN BUILD INTO THE NORTHEAST THE LATTER HALF OF THE WORK WEEK
BEFORE SHIFTING OFFSHORE ON SATURDAY. A WARM FRONT IS FORECAST TO
MOVE THROUGH THE FORECAST AREA ON SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE FORECAST AREA WILL HAVE A COLD FRONT TO OUR SOUTH TODAY, ANOTHER
COLD FRONT APPROACHING OUR NORTHERN ZONES, AND A FAIRLY ZONAL FLOW
IN THE MID-LEVELS. THAT SAID, THE MAJORITY OF THE CWA SHOULD BE
PRECIP FREE.
WE`LL START THE DAY OFF WITH JUST SOME SMALL POPS ACROSS THE FAR
SOUTH. IN THE AFTERNOON WE`LL SHIFT THOSE SOUTHERN POPS UP TO ABOUT
WILMINGTON. AT THE SAME TIME, WE`LL ADD SOME POPS TO THE POCONOS AND
NORTHWEST NJ. GFS MAV POPS ARE FAVORED.
CAN`T RULE OUT SOME THUNDER, BUT NOT EXPECTING ANYTHING TO PACK A
GREAT PUNCH. IN FACT, WE`RE NOT EVEN IN SPC`S SEE TEXT.
THE MAJORITY OF TEMPS ARE FORECAST TO BE IN THE MID 80S. THE
EXCEPTION OF COURSE WILL BE ACROSS OUR NORTHWEST ELEVATIONS AND THE
COAST.
WEST TO SOUTHWEST WINDS WILL BE IN THE 5 TO 10 MPH RANGE, MAYBE UP
TO 15 MPH THIS AFTERNOON AT TIMES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
THIS PERIOD STARTS WITH THE NORTHERN FRONT POISED TO ENTER THE
FORECAST AREA WHILE THE MID-LEVELS REMAIN ZONAL. POPS EXPAND AND
INCREASE A BIT IN RESPONSE ACROSS THE NORTHERN 1/3 OF THE CWA.
ACROSS THE SOUTHERN 1/3 OF THE CWA, POPS REMAIN IN PLACE WITH THE
SOUTHERN FRONT JUST TO OUR SOUTH.
SMALL POPS FILL IN THE MIDDLE 1/3 OF THE CWA AFTER 06Z AS THE
NORTHERN FRONT CONTINUES TO DRIFT SOUTH. ONCE AGAIN GFS MAV POPS ARE
FAVORED.
TEMPS WILL FALL BACK IN TO 50S ACROSS THE FAR NORTHWEST AND REMAIN
IN THE 60S ELSEWHERE. SOUTHERN DELAWARE WILL REMAIN CLOSE TO 70.
WINDS WILL BE LIGHT OUT OF THE SOUTHWEST.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
THE WRF-NMMB INITIALIZATION LOOKED SLIGHTLY BETTER OVERALL AND THE
SOUNDING PROBLEMS AT ALB AND CHH DID NOT APPEAR TO HAVE AN IMPACT.
OVERALL THE MODELING CONSENSUS WAS BETTER THAN LAST NIGHT WITH A
SLIGHT SLOWING TREND WITH THE SECONDARY COLD FRONT. WITH THE OP GFS
AND WRF-NMMB VERY SIMILAR TO EACH OTHER`S ENSEMBLE MEAN, CONFIDENCE
ABOUT THE TIMING IS INCREASING FOR THE HIEST POPS (NOON-MIDN ON
TUE), UNFORTUNATELY, THESE ARE CRIS-CROSSING FCST PERIODS, SO OUR
POPS ARE MORE OF A REFLECTION TO THE UNCERTAINTY OF WHICH FCST
PERIOD, THAN THE OVERALL PROBABILITIES WHICH APPEAR LIKELY.
AS FOR THE DETAILS, THIS IS A TYPICAL SPLIT WE FIND IN OUR CWA WITH
THE FCST HIGHEST CAPES (WRF SOUNDING LLVL DEW POINTS LOOK MORE
REASONABLE THAN THE GFS) SOUTH AND THE BEST WIND FIELD AND FORCING
NORTH AS WELL AS THE ENTRANCE REGION TO THE 250MB JET. THE
FORECAST CONVECTIVE TEMPS ARE EXPECTED TO BE REACHED, BUT NOT TIL
THE AFTERNOON. GIVEN THE EVER SO SLIGHT SLOWING TREND BY THE
MODELS, THE MORNING POP MENTION MAY VERY WELL BE TOO FAST AND EVEN
THE POPS SOUTH MAY HAVE TO RELY ON SEA/BAY BREEZES TO INITIATE.
REGARDLESS WITH ADDITIONAL HEATING EXPECTED AND FCST CAPES GETTING
TO AROUND 1000J, DECENT FCST BULK SHEAR (WIND BELOW 700MB
ADMITTEDLY WEAK) AND DCAPE APPROACHING 1000J WE WILL HAVE TO WATCH
FOR THE FORMATION OF ROBUST THUNDER. SPC SEE TEXT LOOKS GOOD AT
THIS POINT. SOME MESOSCALE MODELS ARE PREDICTING A SQUALL LINE
MOVING THROUGH THE NORTHERN HALF OF OUR CWA BY LATE IN THE DAY
TUESDAY. AS ANYONE THAT FOLLOWS THESE MODELS, THEY CAN BE
FRIGHTENINGLY ACCURATE, BUT THEY HAVE TO GET THE IGNITION SEQUENCE
CLOSE. ALBEIT WITH BETTER LOOKING TIMING, WE DID UP THE POPS AND
WITH PWATS FCST TO STILL REACH 1.5 INCHES, HEAVY DOWNPOURS NOT OUT
OF THE QUESTION EITHER. BECAUSE OF THE SLOWER FRONTAL TIMING, STAT
GUIDANCE HAS BECOME HOTTER WITH MAX TEMPS. NOT GOING THAT HOT YET
BASED ON RECENT WET CONDITIONS, BUT WE BUMPED MAX TEMPS UP BY
AROUND 5F.
WE NUDGED THE AXIS OF HIGHEST POPS SOUTH ON TUESDAY EVENING AND THEN
LOWER POPS OVERNIGHT. USING A GFS AND ECMWF COMPROMISE, WE KEPT THE
MENTION OF THUNDER THRUT ON TUESDAY EVENING AND IN THE SOUTHERN
PART OF OUR CWA THRU THE NIGHT. MIN TEMPS WERE ALSO BUMPED UPWARD
BECAUSE OF THE SLOWER TIMING.
I GUESS IT SHOULD HAVE COME AS NO SURPRISE AS WE GET CLOSER TO
ASTRONOMICAL SUMMER THAT THE COLD FRONTS ARE STRUGGLING TO MOVE
SOUTHWARD. WHILE THE WAVE ON THE FRONT IS FORECAST TO BE WEAKER, THE
LATEST WRINKLE ABOUT EXTENDING POPS INTO WEDNESDAY COMES FROM A
SHORT WAVE TROF INTERACTING WITH A BANKING AND DEVELOPING UPSLOPE
FLOW. WITH THE OCEAN STILL RELATIVELY COOL, THE STABILIZING
INFLUENCE OF THE ONSHORE FLOW IS DEFLECTING SFC (ALOFT TOO) BASED
INSTABILITY WEST OF OUR CWA. WANT TO SEE WHERE THIS GOES BEFORE WE
GET MORE DOUR, BUT FOR NOW WE INTRODUCED LOW POPS. THE ONSHORE
FLOW COUPLED WITH THE 500MB TROF NOT THROUGH SHOULD HELP
GENERATE/PERPETUATE CLOUDINESS, SO WE DID KEEP THE IDEA OF A
CHILLY DAY ALONG THE COAST AND KNOCKED DOWN MAX TEMPS ABOUT 1OF
FROM TUESDAY.
NOT GOING THERE WITH THE WRF-NMMB FOGGING US IN ON WEDNESDAY
NIGHT. THE AIR MASS IS FCST TO BE DRYING, SO HAVE TO SEE THE SFC
HIGH STRUGGLE MORE THAN CURRENTLY PROGGED. DRIER AIR AROUND THE
SFC HIGH EVEN IF WEAK ONSHORE FLOW WILL MAKE FOR A SUNNIER DAY ON
THURSDAY WITH MAX TEMPS STILL SLIGHTLY BELOW NORMAL.
NO BIG CHANGES BEYOND THAT. A DISSIPATING COLD FRONT IS NOT
FORECAST TO BRING ANY PCPN OUR WAY ON FRIDAY AND MIGHT EVEN IN ITS
DEMISE HELP SLOW THE ARRIVAL OF MORE HUMID AIR. THE WARM FRONTAL
PASSAGE (AND POPS) HAS BEEN PUSHED BACK TO LATE SATURDAY AND
SUNDAY. REGARDLESS BY THE FIRST WEEKEND OF ASTRONOMICAL SUMMER,
TEMPERATURES SHOULD BE AT OR ABOVE AVERAGE.
&&
.AVIATION /08Z MONDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
VFR AT THE TERMINALS EARLY THIS MORNING WITH THE EXCEPTION OF
MILLVILLE. WE`RE LOOKING AT MVFR HERE WITH SOME FOG. A FEW OTHER
TERMINALS WILL PROBABLY FOLLOW MILLVILLE`S LEAD THE NEXT COUPLE OF
HORUS.
AFTER SUN-UP, ALL TERMINALS GO VFR AND REMAIN THAT WAY THROUGH THE
PERIOD EXCEPT IN SHOWERS. FOR NOW, WE`LL HIT KABE IN THE NORTH WITH
SOME SHOWERS AND KILG, KMIV, AND KILG ACROSS THE SOUTH. NOTHING AT
THE PHILLY TERMINALS, TRENTON, OR READING.
WEST TO SOUTHWEST WINDS WILL MAX OUT THIS AFTERNOON AT ABOUT 10 KT
TODAY AND FALL BACK IN THE 5 TO 10 MPH RANGE TONIGHT.
OUTLOOK...
TUESDAY AND TUESDAY NIGHT...MVFR OR LOWER AT TIMES WITH SHOWERS
AND THUNDERSTORMS. THERE COULD BE SOME MVFR/IFR LATE AT NIGHT DUE
TO SOME FOG.
WEDNESDAY...POCKETS OF MVFR CONDITIONS IN THE MORNING, OTHERWISE
VFR.
WEDNESDAY NIGHT THROUGH FRIDAY...VFR.
&&
.MARINE...
NO HEADLINES WILL BE ISSUED THIS MORNING FOR AREA WATERS.
SOUTHWEST WINDS WILL PEAK IN THE 10 TO 15 MPH RANGE THIS AFTERNOON.
OCEAN WAVES WILL BE IN THE 2 TO 4 FOOT RANGE WITH 1 TO 2 ON DELAWARE
BAY.
NOT MUCH CHANGE TONIGHT EXCEPT WE`LL THROW SOME 20 KT GUSTS INTO THE
FORECAST WITH THE ARRIVAL OF COLD FRONT FROM THE NORTH.
SMALL POPS REMAIN IN THE FORECAST ACROSS THE SOUTH TODAY AND EXPAND
TO INCLUDE THE NORTH TONIGHT.
OUTLOOK...
RIGHT NOW WE ARE NOT OUTLOOKING SCA CONDITIONS TO OCCUR THROUGH
FRIDAY. THE LOW PRESSURE SYSTEM ON THE FRONTAL BOUNDARY IS FORECAST
TO BE WEAKER THAN LAST NIGHT. HOWEVER, THE WAY THE HIGH PRESSURE
SYSTEM IS FORECAST TO BUILD INTO THE AREA WATERS IS NOW BRINGING
MORE OF A NORTHEAST TO EAST FETCH WEDNESDAY INTO THURSDAY. WE WILL
SEE IF THIS NEW DEVELOPMENT HAS STAYING POWER AND WHETHER OR NOT THE
ONSHORE FLOW AND SWELLS GET ENHANCED ENOUGH TO POSSIBLY REACH SCA
CONDITIONS. THEN THE LIKELIHOOD OF SUB SMALL CRAFT ADVISORY
CONDITIONS INCREASES ON FRIDAY AS THE SFC HIGH SETTLES NEARBY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...GIGI/GORSE
NEAR TERM...KRUZDLO
SHORT TERM...KRUZDLO
LONG TERM...GIGI
AVIATION...GIGI/GORSE/KRUZDLO
MARINE...GIGI/KRUZDLO
000
FXUS61 KPHI 170159
AFDPHI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
959 PM EDT SUN JUN 16 2013
.SYNOPSIS...
AN AREA OF LOW PRESSURE WILL TRACK FROM THE GREAT LAKES INTO
SOUTHEASTERN CANADA INTO MONDAY. A WEAK COLD FRONT ASSOCIATED WITH
IT IS FORECAST TO SETTLE ACROSS OUR AREA TONIGHT. A SECONDARY COLD
FRONT SHOULD THEN ARRIVE TUESDAY WITH A WEAK LOW PRESSURE SYSTEM
FORMING ALONG IT. HIGH PRESSURE WILL THEN BUILD INTO THE AREA
WEDNESDAY AND THURSDAY, BEFORE SHIFTING TO OUR EAST FRIDAY INTO
SATURDAY. A WARM FRONT MAY THEN LIFT NORTHWARD NEAR OUR AREA
SATURDAY, WITH A COLD FRONT WELL TO OUR WEST SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
MOST OF THE SHOWER/THUNDERSTORM ACTIVITY HAS MOVED OFF THE COAST,
EXCEPT FOR AN AREA OF SHOWERS/THUNDERSTORMS ACROSS SOUTHERN
DELMARVA, AS A WEAK SURFACE TROUGH HAS PASSED THROUGH THE AREA.
THERE IS ALSO A FEW SHOWERS MOVING THROUGH SOME OF THE NORTHERN
COUNTIES LATE THIS EVENING WHICH SHOULD CONTINUE TO DISSIPATE AS
THEY SLIDE TO THE SOUTHEAST. A WEAK FRONTAL BOUNDARY IS FORECAST
TO SETTLE ACROSS THE AREA TONIGHT WHILE ANOTHER PIECE OF VORTICITY
IS FORECAST TO SLIDE ACROSS THE SOUTHERN AREAS OVERNIGHT.
THEREFORE, THERE WILL REMAIN SOME ACTIVITY ACROSS SOUTHERN
PORTIONS OF THE DELMARVA FOR A FEW MORE HOURS. THERE ARE A FEW
SCATTERED SHOWERS/THUNDERSTORMS ACROSS WESTERN AND CENTRAL
PENNSYLVANIA ASSOCIATED WITH A LITTLE PIECE OF VORTICITY TO OUR
WEST. HOWEVER, NEAR TERM MODEL GUIDANCE DISSIPATES THIS ACTIVITY
BEFORE REACHING OUR AREA; BUT WE WILL CONTINUE TO MONITOR THESE
SHOWERS.
TEMPERATURES TONIGHT WILL BE QUITE MILD COMPARED TO THE PAST COUPLE
OF MORNINGS. WITH AMPLE LOW-LEVEL MOISTURE IN PLACE AND HIGH CLOUDS
OVERHEAD WE COULD SEE SOME GROUND FOG OR HAZE DEVELOPMENT BY LATE
TONIGHT. TEMPERATURE WISE WE SHOULD ONLY BE ABLE TO DROP BACK INTO
THE UPPER-60S ACROSS THE AREA AS WE USED A BLEND OF THE MET/MAVMOS
TONIGHT.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
MUCH CAN BE SAID OF TOMORROW THAT CAN BE SAID OF SUNDAY WITH AN
ALMOST IDENTICAL SYNOPTIC SETUP. STILL HAVE THE ZONAL FLOW ALOFT
KICKING THROUGH MULTIPLE SHORTWAVES TO OUR NORTH AND POSSIBLY
ANOTHER WEAK OR REMAINING TROUGH TO OUR SOUTH. THESE TWO AREAS COULD
SEE MORE WIDELY SCATTERED SHOWERS AND THUNDERSTORMS. TOMORROW DOES
NOT LOOK MUCH BETTER IN TERMS OF CONVECTION THOUGH THE THERMAL
PROFILES ARE MORE CONDUCIVE WITH BETTER SURFACE BASED CAPE AND LESS
CLOUD COVER, THOUGH THE WEAKER WINDS/SHEAR WOULD PROHIBIT BETTER
UPDRAFT STRENGTH. STILL MAINTAIN THE CHANCE POPS LATER IN THE
AFTERNOON WITH THUNDER BUT THIS WILL ONCE AGAIN HAVE TO BE
REASSESSED TO THE POTENTIAL FOR HOW STRONG ANY OF THE STORMS, IF
THEY FORM, WILL BE.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
THE OVERALL SYNOPTIC SETUP IS COMPRISED OF GRADUALLY RISING HEIGHTS
AS A PACIFIC NORTHWEST CLOSED LOW DRIFTS NORTHEASTWARD INTO SOUTHERN
CANADA. A RIDGE OVER THE PLAINS BUILDS INTO THE MISSISSIPPI VALLEY,
AND THE TROUGH IN THE EASTERN U.S. RELAXES. GIVEN THIS FLOW REGIME,
SYSTEMS LOOK TO BE ON THE WEAKER SIDE AS THEY SLIDE ACROSS THE AREA.
A FRONT SHOULD CLEAR THE AREA LATER TUESDAY, FOLLOWED BY A DRIER
AIRMASS. THE EVOLUTION OF SYSTEMS LATE IN THE WEEK AND NEXT WEEKEND
IS SOMEWHAT UNCERTAIN, GIVEN TIMING OF ENERGY EJECTING INTO THE
NORTHERN PLAINS AND ACROSS THE GREAT LAKES. THIS MAY HANG BACK
AWHILE AS HIGH PRESSURE SITS NEAR THE EAST COAST. WE USED A MODEL
BLEND FOR MONDAY NIGHT INTO WEDNESDAY, THEN WPC GUIDANCE THEREAFTER.
SOME ADJUSTMENTS WERE MADE AFTER ADDITIONAL COLLABORATION WITH OUR
NEIGHBORING OFFICES. WPC USED A BLEND OF THE 06Z GEFS/ECMWF ENSEMBLE
MEANS.
FOR MONDAY NIGHT AND TUESDAY...LOW PRESSURE WILL BE TRACKING TO OUR
NORTH AS A CLOSED LOW SLIDES EASTWARD ACROSS SOUTHERN CANADA. AN
ASSOCIATED COLD FRONT WILL GRADUALLY SETTLE SOUTHEASTWARD ACROSS OUR
CWA DURING THIS TIME FRAME. AS AN UPPER-LEVEL TROUGH AMPLIFIES SOME
SOUTHWARD, STRONGER DEEP LAYER SHEAR SLIDES MAINLY ACROSS THE GREAT
LAKES REGION. THERE SHOULD BE ONGOING CONVECTION WITHIN THIS
CORRIDOR, HOWEVER SOME OF THIS ACTIVITY MAY ARRIVE ACROSS OUR
NORTHERN DURING MONDAY EVENING. IF THIS WERE TO OCCUR, IT SHOULD
WEAKEN WITH THE LOSS OF DAYTIME HEATING THEN WE PERHAPS AWAIT FOR
OTHER CONVECTION IN THE UPPER OHIO VALLEY AND EASTERN GREAT LAKES TO
SLIDE EAST-SOUTHEASTWARD. IN ADDITION, MODEL GUIDANCE SUGGESTS A LEE
SIDE TROUGH COULD BE IN PLACE WHICH MAY ALLOW FOR ISOLATED/SCATTERED
CONVECTION MONDAY EVENING TO PUSH ACROSS PORTIONS OF OUR SOUTHERN
ZONES BEFORE DISSIPATING.
A WEAK WAVE OF LOW PRESSURE THEN LOOKS TO DEVELOP ALONG THE BOUNDARY
AND TRACK NEAR OUR AREA TUESDAY. OUR REGION LOOKS TO REMAIN ON THE
SOUTHERN PERIPHERY OF THE STRONGEST 500 MB FLOW, HOWEVER SOME
INCREASE IS FORECAST ALONG WITH ENOUGH INSTABILITY TO RESULT IN SOME
SHOWERS AND THUNDERSTORMS. WE ALSO LOOK TO BECOME SITUATED WITHIN
THE FAVORABLE ENTRANCE REGION OF THE 250 MB JET DURING THE
AFTERNOON, ALLOWING FOR SOME ASSISTANCE IN THE LARGE SCALE LIFT. THE
THUNDERSTORM COVERAGE AND/OR INTENSITY MAY END UP BEING TEMPERED BY
THE CLOUD COVER AROUND. WE MAINTAIN CHC POPS FOR AT LEAST SCATTERED
COVERAGE DURING THE DAY AS THE FRONT SETTLES SOUTHEASTWARD AND THE
WEAK WAVE MOVES NEARBY. WHILE THE HIGHER PW VALUE AIR LOOKS TO SLIDE
SOUTH AND EAST OF THE AREA, THE PW IS FORECAST TO BE ABOUT 1.25-1.50
INCHES ACROSS OUR AREA. THIS CAN STILL PRODUCE LOCAL DOWNPOURS
ESPECIALLY WITH ANY STRONGER CONVECTIVE ELEMENTS. OUR CONFIDENCE IS
A BIT LOW REGARDING TEMPERATURES AS A FAIR AMOUNT OF CLOUDINESS
COMBINED WITH SOME SHOWERS/THUNDERSTORMS MAY HAVE ENOUGH OF AN
AFFECT.
FOR WEDNESDAY AND THURSDAY...A NARROW UPPER-LEVEL RIDGE IS FORECAST
TO MOVE EAST ACROSS THE PLAINS AND MIDWEST WEDNESDAY AHEAD OF A
LARGE TROUGH IN THE WEST. THIS ALLOWS SURFACE HIGH PRESSURE TO
SETTLE OVER OUR AREA DURING THIS TIME FRAME, AND PUSH A COLD FRONT
TO OUR SOUTH AND EAST. THE ECMWF IS SLOWER WITH THE FRONT AND WANTS
TO MAINTAIN SOME CONVECTION INTO AT LEAST OUR SOUTHERN AREAS. WE
LEANED TOWARD A QUICKER SOUTHWARD PUSH ATTM DUE TO THE INCOMING
SURFACE HIGH. A PERSISTENT UPPER-LEVEL TROUGH HOWEVER IS FORECAST TO
BE ACROSS EASTERN CANADA, THEREFORE THE SURFACE HIGH WILL TEND TO
SETTLE DUE EASTWARD DURING THURSDAY. A NORTH-NORTHEAST LOW-LEVEL
FLOW WEDNESDAY MAY BECOME ONSHORE ESPECIALLY AS THE FLOW ALOFT
LESSENS WITH HIGH PRESSURE ARRIVING. AS A RESULT, A SEA/BAY BREEZE
MAY DEVELOP ESPECIALLY THURSDAY WITH EVEN WEAKER FLOW. IN
ASSOCIATION WITH THE INCOMING SURFACE HIGH, A MUCH DRIER AIRMASS
SHOULD SETTLE IN. SINCE HIGH PRESSURE BECOMES THE DOMINANT FEATURE,
A DRY FORECAST WAS CONTINUED.
FOR FRIDAY AND SATURDAY...THE RIDGE IN THE MIDWEST AREA SHOULD
FLATTEN OUT OR PUSH SOUTHWARD AS ENERGY EJECTS OUT OF THE WEST. AS A
RESULT, LOW PRESSURE IS FORECAST TO TRACK ACROSS THE NORTHERN PLAINS
AND MIDWEST DURING THIS TIME FRAME. MEANWHILE, HIGH PRESSURE IS
SITUATED TO OUR EAST WITH A RETURN FLOW OCCURRING ACROSS THE
NORTHEAST. IT APPEARS THAT A WARM FRONT MAY LIFT NORTHWARD LATE
FRIDAY INTO SATURDAY, ALTHOUGH THE MAIN WAA PUSH MAY END UP STAYING
WELL TO OUR WEST. THERE IS THE POTENTIAL THAT SOME SORT OF WEAKNESS
OR COASTAL TROUGH DEVELOPS NEAR THE CAROLINAS WITH CONVECTION
OCCURRING. SOME OF THIS MOISTURE MAY EVENTUALLY GET DRAWN NORTHWARD
AS LOW-LEVEL WAA AND MOISTURE ADVECTION INCREASES WELL IN ADVANCE OF
THE NEXT SYSTEM. BASED ON SOME UNCERTAINTY WITH THE DETAILS MAINLY
TIED TO A POSSIBLE WARM FRONT, WE WENT DRY FRIDAY THEN CARRIED
SLIGHT CHC POPS IN THE DATABASE ACROSS MUCH OF THE AREA SATURDAY.
FOR SUNDAY...OUR REGION SHOULD BE IN A WARM SECTOR AS HIGH PRESSURE
IN THE ATLANTIC EXPANDS WESTWARD SOME. THIS IS IN RESPONSE TO A
TROUGH SLIDING ACROSS THE NORTHERN PLAINS AND GREAT LAKES. AS THIS
OCCURS, A COLD FRONT WITH POSSIBLY SOME WAVES OF LOW PRESSURE ALONG
IT WILL BE TRAVERSING EASTWARD. FOR NOW, THIS LOOKS TO HANG BACK FAR
ENOUGH TO OUR WEST ALTHOUGH A SMALL CHC OF SOME SHOWERS/THUNDER
CANNOT BE RULED OUT THEREFORE CARRIED SLIGHT CHC POPS IN THE
DATABASE.
&&
.AVIATION /01Z MONDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
THIS EVENING THROUGH TONIGHT...VFR. NOW THAT THE SHOWERS HAVE MOVED
THROUGH AND THE SUN HAS SET, WINDS WILL BECOME LIGHT, AND GENERALLY
FROM THE SOUTHWEST. WITH A MOIST AIRMASS IN PLACE AND ONLY HIGH
CLOUDS IN PLACE OVERNIGHT, SOME TERMINALS COULD SEE MVFR VSBYS
FORM BY LATE TONIGHT WITH EITHER A LIGHT GROUND FOG OR HAZE.
MONDAY...VFR. ANY GROUND FOG/HAZE WILL DISSIPATE BY LATE MORNING
ONCE WE BEGIN TO MIX. WINDS SHOULD BACK A BIT TOWARDS THE WEST BUT
REMAIN LIGHT. THERE COULD BE SOME GUSTINESS AGAIN TOMORROW AFTERNOON
BUT SHOULD BE IN THE UPPER TEENS RANGE.
OUTLOOK...
MONDAY NIGHT...MOSTLY VFR. LOCALIZED MVFR POSSIBLE WITH A SHOWER OR
THUNDERSTORM IN THE EVENING, THEN PERHAPS WITH LOCAL FOG LATE.
TUESDAY...MVFR OR LOWER AT TIMES WITH SOME SHOWERS AND
THUNDERSTORMS. THERE COULD BE SOME MVFR/IFR LATE AT NIGHT DUE TO
SOME FOG.
WEDNESDAY THROUGH FRIDAY...OVERALL VFR.
&&
.MARINE...
CURRENTLY ACROSS OUR WATERS THE SEAS HAVE NOT RESPONDED AS
ORIGINALLY THOUGHT TO THE STRONGER SOUTHERLY SURGE. THIS MAY BE DUE
TO THE SLIGHTLY OFFSHORE COMPONENT THE WINDS HAVE MAINTAINED. SEEING
THAT THE CONDITIONS SHOULD NOT WORSEN THROUGH THE EVENING AND
OVERNIGHT HOURS DECIDED TO CANCEL THE SCA FOR OUR WATERS. THOUGH
THERE COULD POTENTIALLY BE A 25KT GUST IN PLACES AND SEAS MAY BUILD
UPWARDS OF 4 FEET TONIGHT DID NOT FEEL STRONG ENOUGH TO KEEP THE SCA
GOING. OTHERWISE TOMORROW SHOULD FEATURE SLIGHTLY LESS WIND ACROSS
OUR WATERS WITH SEAS ONCE AGAIN RUNNING AROUND 3 FEET.
OUTLOOK...
A COLD FRONT WILL BE SETTLING ACROSS THE AREA TUESDAY, AND A WEAK
WAVE OF LOW PRESSURE SHOULD TRACK ALONG IT. THERE STILL IS SOME
DIFFERENCES WITH THE SOUTHWARD PUSH OF THE COLD FRONT TUESDAY AND
WEDNESDAY, HOWEVER THE SURFACE LOW LOOKS WEAK ENOUGH TO KEEP THE
WINDS UNDER 25 KNOTS. AS THE WEAK SURFACE LOW DEPARTS, HIGH PRESSURE
STARTS TO BUILD IN AND THE PRESSURE GRADIENT TIGHTENS. A NORTHERLY
WIND SHOULD INCREASE SOME WEDNESDAY BEFORE THE PRESSURE GRADIENT
RELAXES, HOWEVER THE OVERALL FLOW LOOKS TO GENERALLY REMAIN UNDER 25
KNOTS. THERE IS A CHC SEAS REACH 5 FEET FOR A TIME, HOWEVER THIS
POTENTIAL LOOKS MARGINAL ATTM. THE WINDS ARE FORECAST TO BE LIGHTER
LATER WEDNESDAY INTO FRIDAY AS HIGH PRESSURE SETTLES OVERHEAD.
THIS SHOULD RESULT IN THE WINDS TURNING MORE SOUTHERLY, WITH
PERHAPS A SEA/BAY BREEZE CIRCULATION OCCURRING.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...GORSE
NEAR TERM...HEAVENER/ROBERTSON
SHORT TERM...HEAVENER
LONG TERM...GORSE
AVIATION...GORSE/HEAVENER/ROBERTSON
MARINE...GORSE/HEAVENER
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