165
FXUS61 KPHI 161342
AFDPHI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
942 AM EDT WED OCT 16 2013
.SYNOPSIS...
AN AREA OF HIGH PRESSURE OVER THE CANADIAN MARITIMES WILL EXTEND
SOUTHWESTWARD OVER THE EASTERN PORTION OF THE NATION. THIS HIGH
WILL SLOWLY MOVE EASTWARD AS LOW PRESSURE OVER THE GREAT LAKES
MOVES EAST AND BRINGS A COLD FRONT THROUGH THE REGION LATE
TONIGHT. THIS FRONT IS THEN EXPECTED TO STALL NEAR THE AREA AND A
WAVE OF LOW PRESSURE WILL DEVELOP ALONG IT AND MOVE ACROSS THE MID
ATLANTIC STATES THURSDAY NIGHT. HIGH PRESSURE WILL BUILD BACK IN
FOR FRIDAY AND SATURDAY, WITH A WEAK COLD FRONT EXPECTED SATURDAY
NIGHT. A LARGE AREA OF HIGH PRESSURE WILL THEN BUILD BACK IN FOR
EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CLOUDY SKIES THIS MORNING WILL GIVE WAY TO PARTLY CLOUDY SKIES
THIS AFTERNOON. IT WILL TAKE A WHILE FOR THE CLOUDS TO CLEAR OUT
AND IT MAY REMAIN CLOUDIER TO THE NORTH AND WEST THROUGH THE DAY.
TEMPERATURES TODAY WILL BE SLIGHTLY ABOVE NORMAL WITH HIGHS INTO
THE 60S AND LOWER 70S ACROSS THE REGION.
AS FOR ANY RAIN REACHING OUR FCST AREA LATE TODAY AHEAD OF THE WEAK
COOL FRONT ENTERING WESTERN OHIO AT 6AM...PROBABLY NONE.
CONFIDENCE ON FCSTG A SHOWER IS BELOW AVG AND BASICALLY ITS
RESTRICTED TO THE POCONOS. THE POPS ARE A THIRD EACH OF 00Z/16
NAM/GFS AND 21Z/15 SREF.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
WEAK WAA WHICH MEANS A CHC OF PATCHY FOG LATE. UPS FOG TOOL GAVE
NOTHING BUT RAN THE FOGGER WHICH WAS MORE EXTENSIVE AND I THINK
THAT WILL VERIFY. TEMPORARY MIDNIGHT CIGS ABOVE 3000FT MIGHT LIMIT
THE CHC OF FOG BUT THE 15Z/21 AND 03Z/16 SREF PROBS FOR LESS THAN
A MILE ARE DRAMATICALLY HIGHER THAN THEY WERE FOR THIS MORNINGS 1
MILERS THAT OCCURRED AT KACY KMIV AND KCGE. FOR EARLY THURSDAY
THE 1 MI PROBS ARE 40 TO 60 PCT ALONG AND NW OF I95.
SINCE THE 24 HOUR LEAD TIME OF THE SREF/NAM PREVAILED FOR THIS
MORNING...I THINK THEY WILL AGAIN TOMORROW MORNING...WITH SUPPORT
FROM THE ECMWF TSEC WHICH IS ALSO MORE EMPHATIC.
AS FOR ANY RAIN...PER THE 06Z-12/16 WPC QPF ASSESSMENT...I SEE LITTLE
CHC EXCEPT NEAR AND N OF I78 AND EVEN THERE...SHOWERS ARE UNLIKELY.
OTHERWISE ALL THE FCST ELEMENTS ARE 50 50 BLENDED 00Z/16 GFS/NAM MOS
GUIDANCE. THE 21Z/15 SREF POP WAS BLENDED IN WITH THE 00Z/16
BLENDED GFS/NAM POPS .. 33PCT EACH SREF/NAM/GFS MOS.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
LOW PRESSURE WILL BE MOVG ACRS ERN CANADA AT THE START OF THE PD
AND WILL BRING A CDFNT THRU THE REGION ERLY. THIS FRONT WILL THEN
STALL AND A WAVE OF LOW PRESSURE WILL DEVELOP ALG THE FRONT AND
MOVE NEWD AND OVER THE AREA THU NIGHT. AS THE LOW MOVES ACRS, RAIN
WILL DEVELOP FROM SW TO NE. THE LATEST MDL GUID HAS THE PRECIP
OVER BY 18/12Z.
HIGH PRESSURE THEN BUILD IN BEHIND THIS DEPARTING LOW AND FRIDAY
AND SATURDAY LOOK QUITE PLEASANT.
ANOTHER AREA OF LOW PRESSURE WILL TRACK ACROSS EASTERN CANADA ON
SATURDAY AND BRING ANOTHER COLD FRONT, ALBEIT A WEAKER ONE, ACROSS
THE REGION SAT NIGHT. CLOUDS WILL INCREASE, AND CAN NOT RULE OUT A
PASSING SHOWER, BUT THAT SHOULD BE THE EXTENT OF IT. THE 16/00Z
ECMWF IS A LOT MORE ROBUST WITH THE CDFNT THAN THE GFS OR CMC, SO IT
THESE TRENDS END UP BEING CORRECT, MAY NEED TO INCREASE POPS A BIT
WITH LATER RUNS, BUT FOR NOW WILL MAINTAIN LOW POPS.
A LARGE AREA OF HIGH PRESSURE THEN BUILDS IN FROM THE WEST FOR THE
START OF THE NEW WEEK.
TEMPS WILL START THE PD ABV NRML, AND DROP TO SLIGHTLY BELOW NRML
BY THE END OF THE PD, BUT OVERALL PLEASANT TEMPS ARE EXPECTED.
&&
.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
IFR/LIFR CEILINGS CONTINUE THIS MORNING AND WILL BE SLOW TO CLEAR OUT
OF THE AREA. WE WILL GRADUALLY SEE AN IMPROVEMENT TO MVFR BY THIS AFTERNOON
WITH SOME LOCATIONS POSSIBLY REACHING VFR FOR A PERIOD OF TIME LATER
TODAY. WINDS REMAIN LIGHT OUT OF THE EAST NORTHEAST AND WILL
GRADUALLY BECOME MORE SOUTHERLY THROUGH THE DAY. WINDS ARE
EXPECTED TO REMAIN LIGHT AND LESS THAN 10 KNOTS ACROSS THE REGION.
TONIGHT...MVFR OR IFR CONDITIONS EXPECTED...ESPECIALLY ALONG AND NW
OF THE INTERSTATE 95 CORRIDOR AIRPORTS WHERE THE 03Z/16 SREF PROB
FOR 1MI VSBY 09-12Z THURSDAY IS 40 TO 60 PCT....MUCH HIGHER FOR IFR
FOG THAN THIS MORNING. SCATTERED SHOWERS POSSIBLE BUT UNLIKELY ONLY
IN THE I78 REGION NORTHWARD WHICH IS BASICALLY NORTH OF OUR TAFS
SITES.
I THINK THE NAM WILL BE THE BETTER FCST FOR THIS COMING NIGHT...ITS
TSEC AND MOS PROBS OUTLOOKING MUCH LOWER CIGS/VSBY THAN THE GFS.
CONFIDENCE: ABOVE AVERAGE FOR IFR CONDITIONS DEVELOPING LATE THIS
COMING WEDNESDAY NIGHT.
OUTLOOK...
THURSDAY...MOSTLY VFR. SOME MVFR PSBL WEST LATE. HIGH CONFIDENCE.
THURSDAY NIGHT...MVFR/IFR CONDS EXPECTED WITH RAIN WITH THE BEST
CHC OF IFR N AND W OF I-95. MDT CONFIDENCE/
FRIDAY THROUGH SATURDAY...VFR. NORTHWEST WIND GUSTS EXCEEDING 20
KTS POSSIBLE FRIDAY. HIGH CONFIDENCE.
SATURDAY NIGHT...MAINLY VFR CIGS. SOME MVFR VSBYS PSBL. MDT
CONFIDENCE.
SUNDAY...VFR. NORTHWEST WIND GUSTS EXCEEDING 20 KTS POSSIBLE. HIGH CONFIDENCE.
&&
.MARINE...
THE SMALL CRAFT ADVISORY HAS BEEN CANCELLED ON THE SOUTHERN OCEAN
WATERS AS SEAS HAVE FALLEN BELOW 5 FEET THIS MORNING.
OTHERWISE, SUB-ADVISORY CONDITIONS ARE EXPECTED TO CONTINUE ACROSS
THE AREA WATERS.
OUTLOOK...
SUB SMALL CRAFT ADVISORY CONDITIONS ARE EXPECTED THROUGHOUT MOST
OF THE OUTLOOK PERIOD. A PAIR OF CDFNTS WILL MOVE THROUGH. ITS
PSBL THAT THERE COULD BE A BRIEF PERIOD OF SCA SEAS OR WIND THU
NIGHT OR FRI MORNING, WITH THE WAVE MOVING UP THE CDFNT. HOWEVER,
CONFIDENCE IS LOW ATTM ON BOTH THE OCCURRENCE AND LENGTH OF TIME,
BUT IT WILL CONTINUE TO BE MONITORED. THEN HIGH PRESSURE MOVES
BACK OVER THE REGION AND NO ADDITIONAL FLAGS ARE EXPECTED. A
SECOND CDFNT WILL MOVE THRU ON SUN NIGHT, BUT THIS IS FRONT IS
FCST TO BE WEAKER SO BOTH WIND AND SEAS SHUD REMAIN BELOW SCA
CRITERIA. HIGH PRESSURE THEN BUILDS BACK IN FOR THE START OF THE
NEW WEEK.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...NIERENBERG
NEAR TERM...DRAG/MEOLA
SHORT TERM...DRAG
LONG TERM...NIERENBERG
AVIATION...DRAG/NIERENBERG/MEOLA
MARINE...NIERENBERG/MEOLA