Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000
FXUS61 KPHI 291253
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
853 AM EDT WED OCT 29 2014

.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS THE AREA TODAY, THEN HIGH PRESSURE
WILL BRIEFLY AFFECT THE AREA THURSDAY. AN AREA OF LOW PRESSURE WILL
MOVE OUT OF THE GREAT LAKES REGION AND SOUTH OF THE AREA ON FRIDAY,
BEFORE COMBINING WITH A DEVELOPING AND STRENGTHENING COASTAL LOW
OFFSHORE OF THE MID ATLANTIC COAST SATURDAY. THIS LOW WILL MOVE WELL
NORTHEAST OF THE AREA ON SUNDAY, THEN HIGH PRESSURE IS EXPECTED TO
BUILD BACK ACROSS THE EAST COAST MONDAY, THEN OFFSHORE TUESDAY AHEAD
OF AN APPROACHING FRONTAL SYSTEM.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MOUNT HOLLY IS ALSO SERVICE BACKING UP STERLING THROUGH 4 PM TODAY.
YOU`LL SEE STERLING FORECAST PRODUCTS ISSUED BY NWS MOUNT HOLLY.

A COLD FRONT COLD FRONT WILL CONTINUE TO PROGRESS EASTWARD THRU
EASTERN PA THIS MORNING AND OFF THE COAST EARLY THIS AFTERNOON.
BASED ON LATEST MODEL GUIDANCE AND OBSERVATIONS, THE TREND WAS TO
SLOW DOWN THE ARRIVAL OF THE SHOWERS AS THE SEPARATION DISTANCE
BETWEEN THE FRONT AND POST-FRONTAL LIFT FROM THE MID-LEVEL TROUGH
GROWS. MADE NOTABLE CHANGES TO THE POP/WX GRIDS TO TAKE THE DELAY
INTO ACCOUNT. SHOWERS NOT EXPECTED TO BE WIDESPREAD AND RAINFALL
AMOUNTS WILL BE LIGHT (GENERALLY AROUND ONE-TENTH INCH). SLIGHTLY
HIGHER AMOUNTS POSSIBLE LATE THIS AFTERNOON AS A WEAK DISTURBANCE
TRAILING THE FRONT IS FORECAST TO TRACKS FROM VA TO THE DELMARVA,
LEADING TO AN ENHANCEMENT OF PRECIP OVER THE SOUTHEASTERN PART OF
THE CWA.

MAX TEMPS RANGE FROM THE LOW 60S IN NORTHEASTERN PA/NW NJ TO AROUND
70F NEAR THE COAST. THESE HIGHS MAY ACTUALLY OCCUR IN WAKE OF
FROPA/PRESSURE TROUGH AS WARMER AIR INITIALLY MIXES DOWN TO THE
SURFACE AND THE COLDER AIR LAGS WELL BEHIND. TEMPS SHOULD FALL
LATER IN THE DAY AFTER THE PRECIP EXITS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
THE COLD FRONT WILL CONTINUE TO MOVE OFF THE EAST COAST TONIGHT. THE
BACK EDGE OF THE LINGERING SHOWERS BEHIND THE BOUNDARY SHOULD BE
SHIFTING THRU THE I-95 CORRIDOR EARLY THIS EVENING AND OFF THE NJ/DE
COAST AROUND MIDNIGHT.

WEST-NORTHWEST WINDS BEHIND THE FRONT WILL ADVECT COLDER AND
EVENTUALLY DRIER AIR INTO THE REGION. SKIES WILL CLEAR NOT TOO LONG
AFTER PRECIP ENDS- DURING THE EVENING ACROSS EASTERN PA AND
NORTHWEST NJ AND OVERNIGHT FOR COASTAL AREAS. THE PRESSURE GRADIENT
WILL BE STRONG ENOUGH FOR A 5-10 MPH WIND TO CONTINUE OVERNIGHT
ESPECIALLY WITH CAA AIDING IN A MIXED NOCTURNAL BOUNDARY LAYER.
THEREFORE, WENT A COUPLE OF DEGREES ABOVE A MAV/MET BLEND FOR MIN
TEMPS.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
HIGH PRESSURE IS EXPECTED TO BRIEFLY AFFECT THE AREA THURSDAY
INTO THURSDAY NIGHT. DRY WEATHER AND NEAR NORMAL TEMPERATURES ARE
EXPECTED BEFORE A DECLINE IN THE WEATHER FOR THE UPCOMING WEEKEND.

ON FRIDAY, AN AREA OF LOW PRESSURE WILL BE MOVING OUT OF THE
GREAT LAKES REGION, AND IS EXPECTED TO MOVE TO THE SOUTH OF THE
AREA WHILE A COASTAL LOW DEVELOPS AND STRENGTHENS TO OUR SOUTH. WE
DO NOT EXPECT MUCH, IF ANY PRECIPITATION DURING THE DAY AS THE
PRECIPITATION TIED TO THE SYSTEM TO OUR WEST SHOULD REMAIN TO OUR
NORTH AND WEST UNDERNEATH THE MID/UPPER LOW/TROUGH. AS WE GO INTO
FRIDAY NIGHT, THE MID/UPPER LOW WILL SWING TO OUR SOUTH, WHILE THE
SURFACE LOW WILL BEGIN GETTING ABSORBED BY THE COASTAL LOW. THIS
WILL ALLOW SOME LIGHT PRECIPITATION TO FILL IN ACROSS THE AREA AS
THE MAJORITY OF THE MODEL GUIDANCE IS INDICATING. IT LOOKS LIKE
ANY PRECIPITATION THAT STARTS OUT FRIDAY NIGHT SHOULD BE MOSTLY A
COLD RAIN AS MODELS NOW KEEP 925/850 MB TEMPS ABOVE FREEZING,
ALTHOUGH IT IS STILL POSSIBLE FOR A MIXTURE ACROSS THE FAR
NORTHERN AREAS.

THE MID/UPPER TROUGH WILL SWING OFFSHORE OF THE NORTH CAROLINA
COAST SATURDAY, WHICH WILL ALLOW THE SURFACE LOW TO STRENGTHEN AND
WRAP UP MORE. THE GFS KEEPS THE PRECIP CLOSE TO THE SURFACE AND
MID-LEVEL LOW AND MOSTLY OFFSHORE, BUT THE ECMWF AND CANADIAN KEEP
PRECIP ACROSS THE ENTIRE AREA AND EXTEND IT PRETTY FAR TO OUR
NORTHWEST, SO WE WILL KEEP A CHANCE OF SHOWERS THROUGH THE DAY
SATURDAY. THE MODELS DO SHOW THE PRECIP MOVING TO OUR NORTHEAST
OVERNIGHT SATURDAY AS THE SURFACE AND MID/UPPER LOW PULL TO OUR
NORTHEAST, SO WE`LL HAVE DECREASING POPS OVERNIGHT. THE MODELS
KEEP THE SUB-FREEZING TEMPERATURES OUT OF THE AREA UNTIL
OVERNIGHT SATURDAY, SO THE BEST CHANCE FOR A MIX OR COMPLETE
CHANGE OVER TO SNOW WILL BE SATURDAY NIGHT INTO SUNDAY MORNING IF
THERE IS STILL ANY REMAINING PRECIPITATION, MAINLY ACROSS THE
NORTHERN THIRD OF THE AREA.

WINDS WILL INCREASE SATURDAY INTO SATURDAY NIGHT AS THE PRESSURE
GRADIENT TIGHTENS SIGNIFICANTLY BETWEEN THE COASTAL LOW AND HIGH
PRESSURE TO THE WEST. WINDS LOOK TO GUST BETWEEN 30-40 MPH, WITH
HIGHER GUSTS POSSIBLE CLOSER TO THE COAST.

SUNDAY IS EXPECTED TO BE DRY, BUT COLD AND BLUSTERY AS A STIFF
NORTHWEST FLOW IS EXPECTED AS THE LOW PRESSURE STRENGTHENS TO OUR
NORTHEAST AND HIGH PRESSURE BEGINS APPROACHING FROM THE WEST. WINDS
COULD CONTINUE TO GUST 30-40 MPH ACROSS THE AREA.

HIGH PRESSURE IS EXPECTED TO BUILD TO OUR SOUTH MONDAY AND NOSE ITS
WAY INTO OUR AREA. THIS WILL PROVIDE FAIR WEATHER WITH TEMPERATURES
RISING BACK CLOSER TO NORMAL.

ON TUESDAY, THE HIGH IS EXPECTED TO BUILD OFFSHORE OF THE SOUTHEAST
COAST, WHILE A WARM FRONT LIFTS NORTH OF THE AREA AHEAD OF THE NEXT
APPROACHING COLD FRONT. AS OF NOW, THE FORECAST FOR TUESDAY IS FOR
DRY WEATHER WITH WARMING TEMPERATURES, ALTHOUGH IF THE WARM FRONT
PASSES CLOSE ENOUGH, A FEW SHOWERS MAY BE POSSIBLE.

&&

.AVIATION /13Z WEDNESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

FOR MOUNT HOLLY:

TODAY...PREDOMINATELY VFR CIGS TODAY AOA 5000 FT. A BRIEF PERIOD OF
MVFR CIGS/VSBYS POSSIBLE WITH HEAVIER SHRA BEHIND A COLD FRONT BUT
CONFIDENCE FOR MVFR CONDS IS VERY LOW AT THIS TIME. LIGHT SHIFTING
WIND TURNING W TO NW AND BRIEFLY GUSTING 20 KT BEHIND THE COLD FRONTAL
PASSAGE.

TONIGHT...VFR CIGS CLEARING FROM WEST TO EAST WITH LEFTOVER RAIN
IN S DELAWARE ENDING. LIGHT NORTHWEST WIND.

FOR STERLING: NWS MOUNT HOLLY IS BACKING UP THIS OFFICE AND THEIR
TAFS THROUGH 20Z TODAY.

TODAY...VFR CIGS. CDFNT CROSSING TERMINALS TDA. THE WSHFT TO NW
WILL COME FIRST...AND IS IN PROGRESS NOW THROUGH KBWI KDCA.
SHOWERS WILL FOLLOW THE WIND SHIFT BY ABOUT 2-4 HOURS AND BRIEF
MVFR CONDS POSSIBLE IN A HEAVIER SHOWER.

TONIGHT...CLEARING WITH A LIGHT NW WIND.


OUTLOOK...

THURSDAY-FRIDAY...MOSTLY VFR.

FRIDAY NIGHT-SATURDAY NIGHT...LOWER END VFR OR UPPER END MVFR WITH
CIGS 2,500-3,500 EXPECTED. LOWER VSBYS POSSIBLE WITH RAIN SHOWERS.
SNOW SHOWERS POSSIBLE ACROSS NORTHEAST PENNSYLVANIA AND NORTHWEST
NEW JERSEY. GUSTY NORTH-NORTHWEST WINDS SATURDAY INTO SATURDAY NIGHT
25-30 KNOTS, POSSIBLY HIGHER NEAR THE COAST.

SUNDAY...VFR. GUSTY NORTHWEST WINDS 25-30 KNOTS.

&&

.MARINE...
NO HEADLINES THROUGH TONIGHT. SW WIND 10-15 KT SHIFTING WNW LATER
THIS AFTERNOON WITH A GUST TO 20 KT POSSIBLE. NW WIND TONIGHT AT
10 TO 15 KT.

OUTLOOK...
THURSDAY-FRIDAY NIGHT...SUB-SMALL CRAFT ADVISORY CONDITIONS
EXPECTED, ALTHOUGH WINDS A SEAS WILL BE INCREASING LATE FRIDAY NIGHT.

SATURDAY-SATURDAY NIGHT...INCREASING WINDS SATURDAY AND SATURDAY
NIGHT AS A COASTAL LOW STRENGTHENS. GALE FORCE WINDS LOOKING MORE
LIKELY.

SUNDAY...GALE FORCE WINDS POSSIBLE EARLY, BEFORE DIMINISHING TO
SMALL CRAFT ADVISORY LEVELS LATE IN THE DAY.

&&

.EQUIPMENT...
SERVICE BACKUP FOR STERLING - LWX TODAY. LISTED UNDER EQUIPMENT...JUST
IN CASE THE MESSAGE IS MISSED IN THE NEAR TERM AND AVIATION SECTION.

&&

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

&&

$$
SYNOPSIS...ROBERTSON
NEAR TERM...DRAG/KLEIN 852
SHORT TERM...KLEIN
LONG TERM...ROBERTSON
AVIATION...DRAG/KLEIN/ROBERTSON 852
MARINE...DRAG/KLEIN/ROBERTSON 852
EQUIPMENT...852







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