Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000
FXUS61 KPHI 220857
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
357 AM EST SAT NOV 22 2014

.SYNOPSIS...
STRONG HIGH PRESSURE WILL REMAIN OVER THE MID ATLANTIC STATES
TODAY BEFORE MOVING OFFSHORE ON SUNDAY. AS THE HIGH MOVES
EASTWARD, THE SOUTHWESTERLY FLOW AROUND IT WILL BRING A WARMING
TREND TO THE AREA. LOW PRESSURE DEVELOPING OVER THE SOUTHERN
PLAINS WILL MOVE NORTHEASTWARD ON SUNDAY AND BRING A WARM FRONT
THROUGH THE REGION SUNDAY NIGHT. THE LOW WILL BE NEAR THE GREAT
LAKES BY MONDAY MORNING AND AS IT MOVES INTO EASTERN CANADA BY
TUESDAY, ITS ASSOCIATED COLD FRONT WILL CROSS THE AREA. HIGH
PRESSURE WILL THEN BUILD IN FROM THE SOUTH FOR MONDAY NIGHT AND
TUESDAY. THEN, AN AREA OF LOW PRESSURE MAY DEVELOP OFF THE
ATLANTIC COAST FOR WEDNESDAY AND WEDNESDAY NIGHT.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE SURFACE HIGH WILL SHIFT FURTHER SOUTHEAST, LEAVING THE REGION
WITH SOUTHERLY RETURN FLOW. AS SUCH, EXPECT MOIST AND WARM AIR
ADVECTION THROUGH THE DAY TODAY. THUS, HIGHS TODAY SHOULD BE AROUND
5 DEGREES HIGHER THAN YESTERDAY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/...
THINGS GET A BIT MORE INTERESTING TONIGHT AS MID LEVEL SHORT WAVE
TROUGH MOVES OVER THE NORTHEASTERN U.S.. BOTH THE GFS AND NAM SHOW
THE BEST SYNOPTIC LIFT (AS EVIDENCED BY 500 MB Q VECTOR CONVERGENCE
AND POSITIVE PRESSURE ADVECTION ON THE 1.5 PV SURFACE) STAYING JUST
NORTH OF OUR REGION. HOWEVER, GIVEN HOW CLOSE THE LIFT IS, AND GIVEN
THAT THERE COULD ALSO BE SOME OROGRAPHIC LIFT, HAVE SLIGHTLY
INCREASED POPS IN THE POCONOS, LEHIGH VALLEY, AND NW NJ. BUT IT
STILL SEEMS LIKE AN UNLIKELY EVENT FOR OUR REGION, SO MOST OF THE
REGION HAS POPS AT OR BELOW 30 PERCENT.

IF THERE IS ANY PRECIPITATION IN OUR AREA, IT WILL BE EITHER IN THE
FORM OF RAIN OR FREEZING RAIN (DEPENDING ON SURFACE TEMPERATURE).
MODEL SOUNDINGS SHOW A ROBUST AND DEEP WARM LAYER. WHILE THERE COULD
BE SOME SEEDER FEEDER CIRRUS CLOUDS PROPAGATING OVERHEAD, WITH THE
MELTING LAYER AROUND 8000 FT MSL, ANY ICE CRYSTALS WOULD MELT
THROUGH THE WARM LAYER. BECAUSE OF THE CONTINUED WARM AIR ADVECTION
EVEN AT THE SURFACE, SEE VERY FEW LOCATIONS DROPPING BELOW FREEZING
BEFORE THE WINDOW OF OPPORTUNITY FOR PRECIPITATION CLOSES. SINCE
TOO, THE CHANCE OF PRECIPITATION IS VERY SMALL AT THIS TIME, WILL
NOT ISSUE A FREEZING RAIN ADVISORY, BUT WILL CONTINUE TO MENTION THE
POTENTIAL IN THE HWO.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
A NICE WARMING TREND IS IN STORE AT THE START OF THE EXTENDD PD AS
HIGH PRES MOVES OFFSHORE AND STRONG SWLY FLOW DEVELOPS OVER THE
AREA.

THEN, LOW PRES WILL TAKE SHAPE OVER THE SRN PLAINS AND BEGIN TO
MOVE NEWD. THE WMFNT ASSOCD WITH THIS LOW WILL MOVE THRU THE
REGION SUN NIGHT AS THE LOW REALLY INTENSIFIES OVER THE MIDSECTION
OF THE NATION. BASED ON THE LATEST GUID MOVG THE PRECIP IN SLOWER,
HAVE REMOVED POPS FROM THE SUNDAY DAYTIME HOURS.  THE BEST WAA IS
SUN NIGHT AND THIS IS THE WETTEST PERIOD WITH RAIN, SOME HEAVY AT
TIMES. WE GET DRY SLOTTED LATER MON AND IN THE WARM SECTOR, TEMPS
WILL SKYROCKET AND COULD REACH RECORD VALUES IN SOME LOCATIONS,
THEN THE COLD FRONT WILL CROSS THE REGION MONDAY NIGHT, WITH
ANOTHER CHC OF PRECIP MON EVE BEFORE HIGH PRES BUILD BACK IN FOR
LATER MON NIGHT THRU TUE NIGHT.

THEN, ALL EYES TURN TO THE POTENTIAL FOR A COASTAL LOW DEVELOPING
AROUND WED. MODEL SOLNS ARE ALL OVER THE PLACE AND CONFIDENCE IS
MUCH BELOW AVERAGE ATTM. THE CMC IS WELL OFFSHORE WITH VIRTUALLY
NO IMPACT TO OUR REGION. THE GFS INDICATES THE MOST IMPACT FOR OUR
SRN AND ERN LOCATIONS WED INTO WED NIGHT BEFORE THE LOW PULLS AWAY
ON THANKSGIVING, BRINGING A DRY HOLIDAY. THE ECMWF HAS THE
STRONGEST AND MOST WWD SOLN AND WOULD BRING A MOSTLY WET AND WINDY
PERIOD FROM WED INTO WED NIGHT. IT HAS SOME SUPPORT FROM THE
UKMET. ANY WINTRY PRECIP WOULD BE CONFINED TO NRN AAND WRN AREAS
AT THE ONSET AND THE END.

WITH THE POTENTIAL FOR SIGNIFICANT IMPACT DUE TO HOLIDAY TRAVEL
AND ONE OF THE BUSIEST AIR TRAVEL DAYS OF THE YEAR, THIS SYS WILL
CONTINUE TO BE WATCHED AND COULD END UP BEING NOTHING OR SOMETHING
SIGNIFICANT. THE ECMWF MADE A DECENT WWD SHIFT FROM 21/12Z TO
22/00Z, THE GFS DID NOT.

AFTER THIS STORMS MOVES BY WHETHER FAR OFFSHORE OR CLOSE TO THE
COAST, ANOTHER WK CDFNT MAY BRING SOME PRECIP ERLY FRI.

TEMPS WILL START OFF FAIRLY WARM ON SUNDAY, REACH THEIR ZENITH ON
MON, WITH NEAR RECORD WARMTH, THEN STILL BE NR NRML ON TUE BEFORE
TAKING A NOSE DIVE THRU THE REMAINDER OF THE WEEK.


&&

.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD. AFTER 18Z, MID
LEVEL CLOUDS WILL INCREASE, PRIMARILY WEST OF THE DE RIVER VALLEY,
INCLUDING KRDG AND KABE, BUT CEILINGS ARE EXPECTED TO BE AT OR ABOVE
5000 FT AGL. THERE IS ALSO A SMALL CHANCE OF -RA OR -FZRA IN THIS
AREA BETWEEN 00 AND 09Z. HOWEVER, AT KRDG AND KABE, IT IS ONLY A 20
PERCENT CHANCE, AND ANY PRECIPITATION SHOULD BE -RA.

OUTLOOK...
SUN...VFR, WITH INCREASING AND LOWERING CLOUDS BY EVENING.
HIGH CONFIDENCE.

SUN NIGHT THROUGH EARLY MON...VERY POOR FLYING CONDS WITH MVFR
EXPECTED AND IFR PSBL IF NOT PROBABLE IN RAIN. RAIN COULD BE HVY
AT TIMES. E TO SE WIND COULD GUST IN THE 20 TO 25 KT RANGE. MDT TO
HIGH CONFIDENCE.

MON AND MON NIGHT...IMPROVING CONDS BUT STILL SOME MVFR PSBL IN
LINGERING SHWRS. CFP/WSFHT MON EVE. VFR BY EVE IF NOT SOONER. LOW
TO MDT CONFIDENCE.

WEDNESDAY...MUCH UNCERTAINTY DEPENDING ON THE TRACK OF A COASTAL
LOW. COULD BE VFR IF LOW IS FAR ENOUGH EAST OR MVFR/IFR IN RAIN
AND WIND IF LOW IS FAR ENOUGH W. BEST CHC FOR VFR IS WRN AIRPORTS.
BEST CHC FOR DEGRADED CONDS IS ERN AIRPORTS. CONFIDENCE VERY LOW.

&&

.MARINE...
WINDS AND SEAS WILL INCREASE BY MID DAY TODAY AS THE HIGH SHIFTS
FURTHER SOUTHEAST. WIND GUSTS OF 25 TO 30 KT WILL BE POSSIBLE ON THE
ATLANTIC COASTAL WATERS THIS AFTERNOON THROUGH VERY EARLY SUNDAY
MORNING. WAVE HEIGHTS UP TO 5 FT ARE EXPECTED IN THE ATLANTIC, AND
MAY BE SLOWER TO DECREASE SUNDAY MORNING. FOR NOW HAVE ISSUED THE
SMALL CRAFT ADVISORY FROM NOON TODAY THROUGH 6 AM SUNDAY MORNING.

OUTLOOK...

SUN...NO MARINE HEADLINES ANTICIPATED.

SUN NIGHT THROUGH MON...SCA CONDS ARE EXPECTED AND GALES ARE PSBL
IF NOT PROBABLE INTO ERLY MON AS STRONG LOW PRES IMPACTS THE
WATERS.

MON NIGHT INTO TUE....BACK END SCA CONDS AS SEAS AND WIND SUBSIDE
SLOWLY.

WED...NO MARINE HEADLINES ANTICIPATED.

&&

.CLIMATE...
HERE ARE SOME RECORD LOWS FOR OVERNIGHT TONIGHT FOR 11/22.

ATLANTIC CITY 12 SET IN 1879
PHILADELPHIA 14 SET IN 1880
WILMINGTON 17 SET IN 1964

ALLENTOWN 17 SET IN 1969 AND 1964 *HAS ALREADY BEEN BROKEN AS
ALLENTOWN HAS HAD A LOW SO FAR OF 16*

TRENTON 15 SET IN 1880
GEORGETOWN 16 SET IN 1987
READING 16 SET IN 1969
MOUNT POCONO 5 SET IN 1969

HERE ARE THE FORECASTED LOWS FOR THIS MORNING.

ATLANTIC CITY 18
PHILADELPHIA 23
WILMINGTON 20
ALLENTOWN 16
TRENTON 21
GEORGETOWN 18
READING 16

ALTHOUGH TEMPERATURES HAVE GENERALLY BEEN INCREASING, WE WILL
CONTINUE TO MONITOR THE TEMPERATURES THROUGH THE EARLY MORNING HOURS
BEFORE SENDING OUT ANY RECORD EVENT REPORTS.
&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FROM NOON TODAY TO 6 AM EST SUNDAY FOR
     ANZ450>455.

&&

$$
SYNOPSIS...NIERENBERG
NEAR TERM...JOHNSON
SHORT TERM...JOHNSON
LONG TERM...NIERENBERG
AVIATION...JOHNSON/NIERENBERG
MARINE...JOHNSON/NIERENBERG
CLIMATE...






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