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000
FXUS61 KPHI 291025
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
525 AM EST FRI NOV 29 2013

.SYNOPSIS...
STRENGTHENING HIGH PRESSURE WILL MOVE ACROSS TO OUR NORTH TODAY
BEFORE SLIDING EAST OF THE REGION OVER THE WEEKEND. A WEAK COLD
FRONT WILL CROSS THE REGION ON SUNDAY. A LOW PRESSURE SYSTEM WILL
DEVELOP OFF THE SOUTHEASTERN UNITED STATES COAST ON MONDAY AND
PASS TO OUR EAST ON TUESDAY. HIGH PRESSURE WILL RETURN FOR
WEDNESDAY AND THURSDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
EARLY THIS MORNING: RAD COOLING AND CLEARING HAS OCCURRED DELMARVA
AND PTNS SE PA AND S NJ. MEANWHILE THE EDGE OF THE CLEARING AT 5
AM WAS ROUGHLY FROM KLNS-KRDG-KABE-KSMQ. LIGHT WIND.

TODAY...A SECONDARY COLD FRONTAL PASSAGE WILL OCCUR BUT WONT BE
EASILY EVIDENT IN THE SFC WINDS. THAT BL COLD FRONTAL BOUNDARY
ATTM - 10Z/29 APPEARS TO LIE ALONG I90 IN NYS. ONCE THE 500 MB
DEFINED SHORT WAVE PASSES EWD ACROSS NYS THIS MORNING...THE SUBTLE
COLD FRONTAL BOUNDARY WILL SAG SEWD.

SKIES SHOULD BE MOCLOUDY JUST AHEAD OF IT NEAR AND N OF I80 UNTIL
IT CLEARS AT SUNSET. ITS POSSIBLE FLURRIES WILL OCCUR IN THE
POCONOS TODAY (00Z/29 SPC WRF SIMULATION)...EVEN A DUSTING OF
SNOW. ELSEWHERE...SUNNY AND NICE. STILL CHILLY WITH MAX TEMPS
ABOUT 10 TO 12 DEGREES COLDER THAN NORMAL. TODAYS FCST TEMPS/DEWS
AND WINDS ARE A 50 50 BLEND OF THE 00Z/29 NAM/GFS MOS GUIDANCE AND
A DEGREE OR 2 COOLER THAN THE FCST FROM THURSDAY AFTN.

THE LIGHT OR CALM WIND AT SUNRISE WILL BECOME NW BY MIDDAY AND
THEN DURING MID AFTN SHOULD GUST 15 MPH FOR A SHORT TIME WITH
SLIGHTLY DESTABILIZING CAA.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
SKIES BECOME CLEAR WITH A LIGHT NORTH WIND DECOUPLING MOST AREAS
LATE. PLENTY OF RADIATIONAL COOLING IS ANTICIPATED AND IT WILL BE
NOTICEABLY COLDER THAN THIS FRIDAY MORNING. THE BOUNDARY LAYER IS
MODELED TO BE ABOUT 4C COLDER THAN THAT OF THIS FRIDAY MORNING AND
SO THE FCST TEMPS ARE LOWER TONIGHT...TEENS FROM READING TO
ALLENTOWN AND SOMERVILLE NORTHWARD...20S ELSEWHERE. UPPER SINGLE
DIGITS ARE POSSIBLE FROM SUSSEX COUNTY NJ INTO MONROE COUNTY PA IN
THE TYPICALLY COLDER LOCATIONS.

ONE EXCEPTION ON LOW TEMPS TONIGHT VCNTY THE IMMEDIATE COAST OF S NJ
AND DE. ONCE THE WIND TURNS ONSHORE (NE)...THE INFLUENCE OF THE WIND
OVER THE WARM WATER COULD RAISE TEMPS BACK INTO THE 30S.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
AT THE SURFACE, HIGH PRESSURE WILL SLIDE ACROSS TO OUR NORTH AND
EAST INTO THE CANADIAN MARITIMES THROUGH THE WEEKEND. A WEAK COLD
FRONT WILL MOVE INTO THE REGION SUNDAY. AN AREA OF LOW PRESSURE
DEVELOPS OFF THE CAROLINA COAST AND TRACKS TO THE NORTHEAST MONDAY
AND TUESDAY. WEAK HIGH PRESSURE WILL BE OVER THE REGION FOR THE
MIDWEEK PERIOD.

IN THE MID-LEVELS, ZONAL FLOW WILL DOMINATE THROUGH THE WEEKEND. A
SHORTWAVE WILL ROTATE THROUGH THE AREA LATE SUNDAY. A TROUGH WILL
DEVELOP ON MONDAY AND DEEPEN BEFORE IT STARTS TO PUSH EAST OF THE
REGION LATE TUESDAY OR WEDNESDAY. RIDGING WILL FOLLOW THE TROUGH AND
PERSIST THROUGH THE END OF THE WEEK.

THE HIGH SLIDES ACROSS TO OUR NORTH AND QUICKLY HEADS EASTWARD INTO
THE CANADIAN MARITIMES OVER THE WEEKEND. AS THE HIGH SHIFTS TO THE
NORTH AND EAST, WE WILL START TO SEE AN EASTERLY FLOW DEVELOP ACROSS
OUR AREA. AS THE HIGH PUSHES TO THE EAST, THE CENTER OF THE HIGH
BECOMES ELONGATED AS PART OF THE HIGH REMAINS ACROSS THE
SOUTHEASTERN UNITED STATES. WITH THE EASTERLY FLOW AROUND THE HIGH
IN OUR AREA, WE WILL SEE AN INCREASE IN MOISTURE ACROSS THE REGION.
THIS WILL INCREASE CLOUDINESS ON SATURDAY, WITH THE CLOUDS HANGING
AROUND INTO EARLY NEXT WEEK. WHILE THE MID-LEVELS ARE STARTING TO
WARM, TEMPERATURES ARE TRENDING COLDER FOR SATURDAY AS COLDER AIR
FILTERS INTO THE REGION IN THE LOWER LEVELS, DUE TO THE EASTERLY
FLOW. DROPPED MAXIMUM TEMPERATURES A COUPLE OF DEGREES, WHICH IS
CLOSER TO THE COOLER GUIDANCE.

SATURDAY LOOKS TO BE A DRY DAY. AS THE MOISTURE LEVELS INCREASE IN
THE EASTERLY FLOW, COMBINED WITH THE WEAK SURFACE FRONT AND A
SHORTWAVE MOVING INTO THE REGION LATE SUNDAY, WE COULD SEE SOME
LIGHT PRECIPITATION FALL ACROSS THE AREA. THIS LOOKS LARGELY
CONFINED TO THE EASTERN AREAS AND WE HAVE KEPT POPS LIMITED TO THE
COASTAL ZONES AND NEARBY INLAND AREAS.

A LOW PRESSURE SYSTEM LOOKS TO DEVELOP OFF THE SOUTHEASTERN UNITED
STATES COAST ON MONDAY, MOVING UP THE CAROLINA COAST AND THEN OUT TO
SEA. MAJORITY OF THE GUIDANCE TAKES THIS SYSTEM AWAY FROM THE COAST
BEFORE IT MOVES FAR ENOUGH NORTH TO HAVE AN IMPACT IN OUR REGION.
WHILE THE CENTER OF THE SYSTEM WILL BE WELL AWAY FROM THE COAST,
SOME SHOWERS LOOK LIKE THEY MAY MAKE IT INTO THE FORECAST AREA. WE
HAVE KEPT SOME SLIGHT CHANCE TO CHANCE POPS /HIGHER CLOSER TO THE
COAST/ FOR MONDAY AND TUESDAY. THE SYSTEM PULLS FURTHER AWAY BY LATE
TUESDAY AND ANY LINGERING LIGHT SHOWERS SHOULD DISSIPATE.

HIGH PRESSURE WILL RETURN FOR WEDNESDAY AND THURSDAY. ANOTHER LOW
PRESSURE SYSTEM STARTS TO MOVE TOWARD OUR REGION.

TEMPERATURES WILL REMAIN BELOW NORMAL THROUGH THE PERIOD. HIGHS WILL
MAINLY BE IN THE 30S/40S WITH LOWS IN THE 20S/30S ACROSS THE
REGION.

&&

.AVIATION /10Z FRIDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

THROUGH 12Z...VFR CIGS AOA 5000 FT FROM KRDG-KABE NWWD WITH SCT TO
BRIEFLY BKN CLOUDS AOA 8000 FT ELSEWHERE.

AFTER 12Z...VFR SCT-BKN AOA 4000 FT VCNTY KABE/KRDG THROUGH 19Z
AND VFR SCT AOA 5000 FT ELSEWHERE. BRIEF MVFR CONDS POSSIBLE
MIDDAY IN THE POCONOS IN FLURRIES. WIND MOSTLY NW WITH AFTN
GUSTS INCREASING TO BETWEEN 15 AND 18 KT...STRONGEST VCNTY KABE.
FCSTR CONFIDENCE: ABOVE AVERAGE.

TONIGHT...VFR FEW CIRRUS. NORTH WIND UNDER 10 KT BECOMING NE DURING
THE NIGHT. FCSTR CONFIDENCE: WELL ABOVE AVERAGE.

OUTLOOK..
SATURDAY...VFR CONDITIONS EXPECTED. NORTHEASTERLY WINDS AROUND 10
KNOTS OR LESS.

SUNDAY...VFR CONDITIONS EXPECTED. LIGHT EASTERLY WINDS WILL
GRADUALLY BECOME MORE WESTERLY AROUND 10 KNOTS OR LESS. LOWER
CONDITIONS POSSIBLE, MAINLY NEAR THE COAST.

MONDAY THROUGH TUESDAY...MAINLY VFR CONDITIONS EXPECTED. NORTHERLY
WINDS AROUND 10 KNOTS. LOWER CONDITIONS POSSIBLE LATE MONDAY AND
TUESDAY.

&&

.MARINE...
NO MARINE WATCHES/WARNINGS/ADVISORIES THROUGH TONIGHT.

LIGHT WEST WIND THIS MORNING BECOMES NORTHWEST BY AFTN WITH GUSTS 15-20
KT LATE IN THE DAY. THEN THE WIND TURNS NORTH AND EVENTUALLY NE DURING
FRIDAY NIGHT. SEAS MAY BUILD TO 4 FT ON THE ATLC WATERS FRIDAY NIGHT.
RIGHT NOW A PREDOMINANTLY ESE SWELL OF 2 FT AND 9 OR 10 SECONDS IS
SHOWING UP IN THE WATERS AND IS EXPECTED TO BE DOMINANT INTO TONIGHT.

OUTLOOK...
SATURDAY...HIGH PRESSURE WILL PASS TO THE NORTH OF THE REGION.
SUB-ADVISORY CONDITIONS ARE EXPECTED.

SUNDAY...A WEAK COLD FRONT WILL CROSS THE WATERS LATE. WINDS AND
SEAS WILL INCREASE BUT WILL REMAIN BELOW SMALL CRAFT ADVISORY LEVELS.

MONDAY...SUB-ADVISORY CONDITIONS ARE EXPECTED.

TUESDAY...A LOW PRESSURE SYSTEM MOVES OFF THE CAROLINA COASTLINE
WHICH MAY INCREASE SEAS TO NEAR SMALL CRAFT ADVISORY CRITERIA,
MAINLY ACROSS THE SOUTHERN WATERS.

&&

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

&&

$$
SYNOPSIS...MEOLA
NEAR TERM...DRAG 524
SHORT TERM...DRAG 524
LONG TERM...MEOLA
AVIATION...DRAG/MEOLA 524
MARINE...DRAG/MEOLA