Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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FXUS61 KPHI 171519
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1019 AM EST MON NOV 17 2014

.SYNOPSIS...
TWO WAVES OF LOW PRESSURE ARE PASSING THROUGH THE NORTHEAST TODAY. A
WEAK LOW IS MOVING NORTHEAST OFF THE MID ATLANTIC COAST THIS MORNING
AND A SECOND STRONGER LOW CURRENTLY IN TENNESSEE...IS DESTINED TO
ZIP UP TO QUEBEC THIS EVENING. THIS LATTER LOW YANKS A STRONG COLD
FRONT OFF THE EAST COAST THIS EVENING. HIGH PRESSURE WILL BUILD INTO
OUR AREA LATER TUESDAY INTO WEDNESDAY, WITH ANOTHER COLD FRONT
ARRIVING THURSDAY. AN AREA OF HIGH PRESSURE IS ANTICIPATED FOR LATE
FRIDAY INTO THE WEEKEND, THEN A WARM FRONT MAY BEGIN TO APPROACH OUR
REGION SUNDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ONE WEAK LOW PRESSURE AREA HAS MOVES NORTHEAST OF THE AREA. A
SECOND LOW WILL MOVE NORTH OF THE AREA THIS AFTERNOON AND CAUSE A
COLD FRONT TO MOVE THROUGH THE AREA LATE THIS AFTERNOON INTO THE
EVENING.

AFTER COORDINATING WITH THE NEARBY OFFICES...WE HAVE DISCONTINUED
THE WSW FOR NORTHWEST NJ AND THE SRN POCONOS. TEMPERATURES HAVE
WARMED BIT OVER THE LAST FEW HOURS AND MOST OF THE UPCOMING PCPN
WILL BE RAIN. WE HAVE ISSUED A SPS WITH WORDING OF THE POSSIBILITY
OF A BIT OF ICE STILL POSSIBLE AT THE HIGHEST ELEVATIONS...BUT
WITH NO REPORTS OF ANY ICE...ITS PROBABLY NOT HAPPENING.

WINDS WILL BEGIN TO INCREASE ACROSS THE AREA AS THE COLD FRONT
ADVANCES TOWARD THE AREA. ROUNDS OF RAIN SHOWERS MAY BE
ACCOMPANIED BY SOME GUSTY WINDS THIS AFTERNOON. A LOW LEVEL JET OF
60-70 KTS WILL BE OVER THE AREA.

MAX TEMPERATURES WILL SHOW DECENT VARIATION ACROSS THE REGION
TODAY WITH LOW 40S UP NORTH AND LOW 60S SOUTH. UPDATES TO
TEMPS/DEW POINTS AND WINDS WERE MADE WITH THE LATEST ESTF.


&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
CONDS WILL IMPROVE TONIGHT.  THE CDFNT WILL CROSS THE REGION FROM W
TO E AND PRECIP WILL COME TO AN END BEHIND IT DURG THE ERLY EVE.  BY
LATE EVE THE RAIN SHOULD BE OVER WITH ACRS THE ENTIRE AREA.  HIGH
PRES WILL GRADUALLY BUILD IN FROM THE SW AND CLOUDS WILL DECREASE.
THE WIND WILL BECOME MORE WLY AND SPEEDS WILL INCREASE AND BECOME
GUSTY.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
500 MB: TROUGH IN EASTERN NORTH AMERICA THIS WEEK WITH A LARGE
PORTION OF IT PASSING THROUGH OUR AREA AND NORTHEASTWARD LATE
TUESDAY...WITH THE NEXT STRONG SHORT WAVE DIVING SOUTHWARD FROM
CENTRAL CANADA PASSING ACROSS THE GREAT LAKES STATES THURSDAY AND
PAST NEW ENGLAND FRIDAY. CONSIDERABLE RIDGING (WARMING ALOFT)
EVOLVES ALONG THE EAST COAST NEXT WEEKEND AS A NEW TROUGH FORMS
IN THE WESTERN PLAINS.

TEMPERATURES: CALENDAR DAY AVERAGES 10 TO 15 COLDER THAN NORMAL
TUESDAY...15 TO 18 BELOW NORMAL WEDNESDAY...AROUND 10 BELOW NORMAL
THU-SAT THEN WARMING SUNDAY. WE SEE THE ECMWF HAS US BACK TO 15
BELOW NORMAL ON SATURDAY BEFORE SWINGING US 10 ABOVE NORMAL NEXT
MONDAY. THE POINT HERE...THERE IS A POTENTIAL SECONDARY
REINFORCEMENT OF THE COLD HERE LATE THIS WORKWEEK...NOT QUITE AS
SIGNIFICANT AS THAT OF TUESDAY-WEDNESDAY BUT STILL NOTABLE.

FORECAST BASIS: UNLESS OTHERWISE NOTED THE LONG TERM PERIOD OF THIS
FORECAST IS GENERALLY BASED ON A 50 50 BLEND OF THE 00Z/17 NAM/GFS
MOS FOR THE PERIOD TUESDAY-WEDNESDAY. THEN THE 00Z/17 GFS MOS IS APPLIED
WEDNESDAY NIGHT AND THURSDAY. THEREAFTER (THURSDAY NIGHT ONWARD)
THE 0604Z/17 WPC GRIDDED GUIDANCE WHICH AT TIMES IS BLENDED 50 50
WITH THE 00Z/17 MEXMOS. ALL THIS IS EVENTUALLY CHECKED AGAINST THE
00Z/17 ECMWF TO SEE IF WE`RE IN THE BALLPARK WITH ECMWF CYCLICALLY
PERSISTENT 18Z 2 METER TEMPERATURES (SEEMS LIKE A RECENT WARM BIAS
IN THOSE EC 2M TEMPS). PRECIPITATION PROBABILITY GUIDANCE IS CHECKED
AGAINST THE 21Z/16 SREF 3HRLY POPS FOR .01 THROUGH 12Z THURSDAY AND
THEREAFTER THE 00Z/17 GEFS 6HR POPS FOR 0.05.

THE DAILIES...

TUESDAY...BLUSTERY AND VERY COLD WITH TEMPERATURES RISING JUST A
COUPLE OF DEGREES FROM 7 AM VALUES...THE HIGH FOR THE DAY PROBABLY
AT MIDNIGHT THIS COMING EARLY TUESDAY MORNING. GUSTY WEST WIND TO
35 MPH...EVEN A FEW GUSTS TO 40 MPH POSSIBLE EASTERN PA AND NJ.

RATHER STEEP LAPSE RATES DEVELOP LATE IN THE DAY AS THE COLD CORE
TROUGH AXIS MOVES BY BUT WILL BE MOISTURE STARVED FOR SNOW SHOWER
PRODUCTION DUE TO THE WESTERLY WINDS KEEPING MOST OF THE LAKE
EFFECT JUST NORTH OF OUR AREA. CONTINUING SLIGHT CHANCE OF SNOW
SHOWERS/FLURRIES OVER THE POCONOS DUE TO THE LARGE LAPSE RATES...
A 12 HR STABILITY CHANGE AND A TROUGH ALOFT PASSAGE.

TUESDAY NIGHT...STILL CONCERNED ABOUT SNOW SHOWERS/FLURRIES
EVENTUALLY TRENDING SLIGHTLY SEWD INTO THE POCONOS BEHIND THE
TROUGH PASSAGE...OTHERWISE THE QUESTION...HOW COLD DOES IT GET...
NEAR RECORD APPEARS PROBABLE. THERE STILL WILL BE A GUSTY WEST
WIND DURING MUCH OF THE NIGHT AND THE WIND CHILL IN THE POCONOS
IS FORECAST BE AS LOW AS 5 BELOW ZERO BY DAYBREAK WEDNESDAY.

FROM THE PREVIOUS SUNDAY AFTERNOON DISCUSSION:
TEMPERATURES ON TUESDAY AND WEDNESDAY WILL BE MORE TYPICAL OF
JANUARY THAN NOVEMBER. SEVERAL OF OUR EIGHT PRIMARY CLIMATE SITES
WERE EXPECTED TO GET WITHIN STRIKING DISTANCE OF THEIR RECORD LOW
TEMPERATURES ON WEDNESDAY MORNING. WE HAVE CONTINUED THE CLIMATE
SECTION WITH THE INFORMATION TOWARD THE BOTTOM OF THIS FORECAST
DISCUSSION.



WEDNESDAY...STILL VERY COLD BUT WITH LESS WIND. INCREASING AFTERNOON
HIGH CLOUDINESS IN WAA AHEAD OF THE NEXT COLD FRONT.

THURSDAY...A DRY COLD FRONT FROM THE NORTHWEST IS ANTICIPATED.
THE AIR MASS BEHIND THE FRONT SHOULD NOT BE AS COLD AS THE ONE
THAT WILL BE AFFECTING OUR REGION DURING THE MID WEEK PERIOD.

FRIDAY-SATURDAY...HIGH PRESSURE IS FORECAST TO BUILD INTO OUR REGION
FROM THE WEST.  THE CENTER OF THE HIGH SHOULD PASS OFF THE MIDDLE
ATLANTIC COAST ON SATURDAY AFTERNOON.

SUNDAY...MOISTURE IS EXPECTED TO BEGIN BUILDING TOWARD OUR REGION IN
THE RETURN FLOW ON THE BACK SIDE OF THE HIGH ON SUNDAY. WE ARE
ANTICIPATING AN INCREASE IN CLOUD COVER ALONG WITH A CHANCE OF
AFTERNOON RAIN. MAXIMUM TEMPERATURES ARE EXPECTED TO REMAIN BELOW
NORMAL ON SUNDAY. THEY SHOULD BE MAINLY IN THE 40S.

&&

.AVIATION /15Z MONDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

THE FIRST PART OF THE FCST IS QUITE POOR, WITH IMPROVEMENT EXPECTED
TONIGHT.

LOW PRES OVER THE SERN STATES WILL MOVE NEWD TWD THE MID-ATLC AND
CROSS THE AREA LATER TODAY.  A WMFNT WILL MOVE THRU THE REGION EARLY
TODAY, FOLLOWED BY A CDFNT LATER THIS AFTN.  BEHIND THE CDFNT CONDS
WILL IMPROVE THRU ERLY EVE, WITH A RETURN TO VFR BY LATE EVE.

HOWEVER, CONDS RANGE FROM VFR TO IFR ACRS THE AREA EARLY THIS AM AND
ARE EXPECTED TO BECOME IFR EVERYWHERE AS THE AFOREMENTIONED LOW AND
ASSOCD RAIN IMPACT THE REGION.  EXPECT POOR FLYING WX FOR THE
BALANCE OF THE DAY.  RAIN COULD BE HVY AT TIMES.

A STRONG LLJ AND INCREASING SWLY FLOW ALOFT DURG THE DAY WILL CREATE
LLWS, ESPECIALLY THIS AFTN, WHICH CUD BE QUITE STRONG IN SPOTS WITH
LIGHT WIND AT THE SFC.


OUTLOOK...
TUESDAY...VFR CLEAR OR SCT CLOUDS AOA 4000 FT WITH A GUSTY WEST
WIND OF 30 TO 38 KT...SLOWLY DIMINISHING AT NIGHT.

WEDNESDAY...VFR WITH CIRRUS OR AC ARRIVING IN THE AFTERNOON/NIGHT.
WEST WIND BACKING TO SOUTHWEST.

THURSDAY...VFR WITH A W WIND 20 TO 25 KT.

FRIDAY...MAINLY VFR WITH A WNW WIND 20 TO 25 KT.

&&

.MARINE...
A GALE WRNG REMAINS IN EFFECT BEGINNING NOON TODAY AND CONTINUING
THRU THE SHORT TERM PD. LOW PRES FROM THE SW WILL MOVE ACRS THE
REGION TODAY.  EXPECT INCREASING SWLY FLOW BEHIND ITS ASSOCD WARM
FRONT TO INCREASE WIND AND SEAS TODAY.  A CFP LATER TODAY WILL CAUSE
THE WIND TO BECOME MORE WLY AND RAMP UP EVEN FURTHER TONIGHT AS THE
PGRAD BETWEEN THE AFOREMENTIONED LOW AND HIGH PRES TO THE W
STRENGTHENS.

OUTLOOK...
TUESDAY INTO TUESDAY NIGHT...A GALE WARNING IS IN EFFECT FOR A GUSTY
WEST TO NORTHWEST WIND. SUSTAINED SPEEDS SHOULD FAVOR THE 20 TO 30
KNOT RANGE WITH GUSTS UP TO 35 OR 40 KNOTS.

WEDNESDAY INTO FRIDAY...SMALL CRAFT ADVISORY CONDITIONS ARE EXPECTED
AT TIMES AS ANOTHER COLD FRONT ARRIVES FROM THE NORTHWEST. EVEN
THE WAA SW WIND WED NIGHT WILL BLOW PRETTY STRONG BECAUSE THE
BOUNDARY LAYER TEMPS ARE MUCH COOLER THAN THE SEA SURFACE.

&&

.CLIMATE...
BELOW IS A LISTING OF RECORD LOW TEMPERATURES AND THE YEAR OF
OCCURRENCE FOR NOVEMBER 19 FOR OUR EIGHT CLIMATE SITES. WE HAVE
ALSO INCLUDED OUR FORECAST LOW TEMPERATURES FOR WEDNESDAY MORNING
NOVEMBER 19, AS THE COLDEST AIR OF THE SEASON THUS FAR ARRIVES
ACROSS THE REGION.

IF RECORDS ARE SET AT ANY OF THESE LOCATIONS OTHER THAN THE RELATIVELY
SHORT TIME CLIMO SITE KGED...I THINK IT SPECIAL SINCE IT WILL BE
WITHOUT SNOWCOVER AND PROBABLY IN A NON RADIATING SITUATION (A GENTLE
BREEZE STIRRING EARLY WED MORNING).


11/19 RECORD LOWS:        11/19 FORECAST LOWS:

ACY 18 1936 ACY 22
PHL 20 1936 PHL 21 NEAR RER
ILG 15 1936 ILG 19
ABE 11 1924 ABE 16
TTN 17 1936 TTN 18 NEAR RER
GED 20 1959 GED 19 RECORD
RDG 18 1936 RDG 16 RECORD
MPO 10 1933 MPO 10 RECORD EQUALING

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...GALE WARNING UNTIL 6 AM EST WEDNESDAY FOR ANZ430-431-450>455.

&&

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






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