Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS61 KPHI 250753
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
353 AM EDT SAT APR 25 2015

.SYNOPSIS...
WEAK HIGH PRESSURE COVERS OUR AREA EARLY TODAY. LOW PRESSURE OVER
THE LOWER OHIO VALLEY WILL PASS OFF THE NORTH CAROLINA COAST SUNDAY.
THAT LOW BECOMES PART OF LARGE LOW PRESSURE CIRCULATION OVER THE
NORTHWEST ATLANTIC EARLY NEXT WEEK. A LOW PRESSURE SYSTEM OVER THE
NORTHERN GULF OF MEXICO TUESDAY NIGHT EMERGES OFF THE SOUTHEASTERN
SEABOARD LATE WEDNESDAY AND THURSDAY AND HEADS NORTHEAST.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
330 AM PACKAGE: NOT MUCH CHANGE IN THE FROST/FREEZE HAZARD AS
RADIATIONAL COOLING VARIES BASED ON THE SFC WIND STIRRING BUT
OVERALL...THE ADVY/WARNING IS REASONABLE AND VERIFYING.

TODAY...VARIABLE HIGH CLOUD COVER. THE THICKER SKYCOVER FROM FAR
SE PA AND SNJ SOUTHWARD. SPRINKLES MAY DEVELOP TOWARD 6 PM OVER
TALBOT/CAROLINE AND SOUTHERN SUSSEX COUNTIES ON THE SW EDGE OF OUR
FCST AREA. FORECAST TEMPERATURES TODAY WERE A 1/3RD BLEND OF THE
00Z/25 GFS/NAM MOS AND 00Z/25 ECMWF 2M TEMPS. THE ECMWF IS QUITE
COOL UNDER THE CLOUDS OVER THE DELMARVA AND HAVE MODIFIED THE
NCEP MOS DOWNWARD THERE. WARMEST TEMPS IN OUR FCST AREA TODAY
SHOULD BE IN NORTHERN NJ WHERE THERE SHOULD BE MORE SUNSHINE.

A NICE DAY WITH MUCH LESS WIND THAN THE PREVIOUS WED-THU-FRIDAY
AFTERNOONS.

DAYTIMES TEMPS WILL BE WARMING A BIT EXCEPT THE DELMARVA WHERE IT
WILL BE CHILLY TODAY AND MAXIMUM TEMPS ALMOST 15 DEGREES BELOW
NORMAL WHILE MAXIMUM TEMPERATURES AROUND ALLENTOWN AND MOUNT
POCONO NEWD THROUGH NNJ SHOULD ONLY BE 8 TO 10 DEGREES BELOW
NORMAL.

A WEAK WIND SHIFT BOUNDARY WILL BE FORMING JUST TO OUR NORTH LATE
IN THE DAY WITH WESTERLY WINDS GUSTING TO 15 MPH DURING THE
AFTERNOON IN PA AND NNJ BUT SEA BREEZES SHOULD DEVELOP COASTAL NJ
AND COASTAL DE. WINDS ON THE DELMARVA WILL BE LIGHT WHERE LESS
MIXING IS EXPECTED DUE TO HEAVIER SKYCOVER.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/...
TONIGHT...THICK HIGH CLOUD ALONG AND SOUTH OF I-78, WITH THE NORTHERN
PORTION OF THE FORECAST RAIN SHIELD A BLEND OF HPC QPF, 50 50
00Z/25 NAM/GFS MOS AND MULTI MODEL .10 IN 6 HRS. THAT MEANS MAINLY
THE SOUTHERNMOST 40 MILES OF OUR CWA, TALBOT COUNTY, QUEEN ANNES
AND CAROLINE COUNTIES IN MD AND SUSSEX COUNTY DE, POSSIBLY KENT
COUNTY DE AND POSSIBLY THE SRN TIP OF NJ. THIS CLOUD COVER TODAY
AND CLOUD COVER/RAIN TONIGHT IS ASSOCIATED WITH THE LOW REDEVELOPING
NEAR THE NC COAST. A WIND SHIFT FROM LIGHT WEST TO NORTH-NORTHEAST
PROGRESSES FROM NORTH TO SOUTH THROUGH OUR CWA DURING THE NIGHT.

PATCHY FROST IS IN THE FCST N OF I-78 TONIGHT. NO NEW FROST ADVY
ATTM DUE TO THE UNCERTAINTY OF THE NORTHERN EDGE OF THICK CLOUD
COVER. IT ALREADY FROZE UP THERE THIS MORNING SO EARLY SUSCEPTIBLE
BLOOMS WERE PROBABLY DAMAGED.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
A LOW PRESSURE SYSTEM WILL BE MOVING OFFSHORE SUNDAY MORNING AND
ITS ASSOCIATED CLOUDS AND LIGHT RAINS WILL BE AFFECTING THE SRN
PARTS OF OUR AREA. SOME LIGHT RAIN WILL PULL AWAY BY EVENING WITH
PERHAPS UP TO A TENTH OF AN INCH POSSIBLE. ELSEWHERE...PARTLY TO
MOSTLY SUNNY NORTH AND CENTRAL AREAS WITH TEMPERATURES NEAR
NORMAL.

COOLER AIR ARRIVES FOR MONDAY AND TUESDAY AS THE LARGE UPPER LOW
OFFSHORE ROTATES A FEW SHORT WAVES AND SFC TROUGHS ACROSS THE
AREA. SCT SHOWERS ARE EXPECTED MONDAY WITH CHC POPS. DRIER AIR
ARRIVES TUE...BUT STILL A SLGT CHC FOR A SHOWER FAR NORTH.
TEMPERATURES WILL RUN SEVERAL DEGREES BELOW NORMAL MON/TUE...WITH
TUE LIKELY THE MILDER DAY.

THE ECMWF/GFS MODELS BOTH SHOW ANOTHER SFC/UPPER LOW STRENGTHENING
ACROSS THE SOUTHEAST STATES AND MOVING NORTHEAST...JUST EAST OF
OUR AREA. IT APPEARS TO BE ANOTHER GLANCING SHOT OF CLOUDS AND
RAINS S/E FOR THU AND INTO EARLY FRI. ANY CHANGES WITH THE TRACK
COULD BRING SOME HEAVIER RAINS TO THE AREA. WE HAVE JUST USED THE
WPF POPS FOR NOW...MOSTLY CHC (THU) AND SLGT CHC (THU NIGHT).
TEMPERATURES WILL RETURN TO NEAR NORMAL FOR THE MIDDLE/LATE PART
OF NEXT WEEK.

&&

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

THROUGH 12Z...VFR CLEAR WITH SCT-BKN CLOUDS AOA 15000 FT ARRIVING
SE PA AND S NJ SOUTHWARD AFTER 09Z. LIGHT NORTH NORTHWEST WIND.

TODAY DURING THE DAY...SCT-BKN AOA 15000 FT MAY BRIEFLY THIN LATE
IN THE DAY. LIGHT WEST - NORTHWEST WIND BECOMING WEST MIDDAY WITH
GUSTS TO 15 KT POSSIBLE DURING THE AFTERNOON IN NJ/PA BUT SEABREEZES
DEVELOP ALONG COASTAL SECTIONS MID AND LATE AFTN.

TONIGHT...CIGS AOA 10000 FT, ESPECIALLY AFTER 03Z/26. A SPRINKLE
POSSIBLE KPHL/KILG/KMIV KACY BUT NOT IN THE FCST ATTM. IT MAY BE
TOO DRY IN THE LAYER UNDER 8000 FT. LIGHT WEST WIND SHIFTING N-NE
DURING THE NIGHT. PLEASE SEE TAFS FOR TIMING DETAILS AS A WIND
SHIFT BOUNDARY SAGS SOUTHWARD.

OUTLOOK...

SUNDAY...MAINLY VFR CONDITIONS, AS ANY SUB-VFR IN RAIN TO START
ACROSS SOUTHERN AREAS WILL IMPROVE BACK TO VFR.

MONDAY...MAINLY VFR CONDITIONS; ALTHOUGH, SOME ISOLATED SHOWERS ARE
POSSIBLE. GUSTY NORTH TO NORTHWEST WINDS, WITH GUSTS TO 20 KNOTS.

TUESDAY AND WEDNESDAY...MAINLY VFR EXPECTED; ALTHOUGH, CONDITIONS
MAY DETERIORATE LATE WEDNESDAY NIGHT DEPENDING ON THE TIMING AND
TRACK OF A POSSIBLE COASTAL LOW PRESSURE.

&&

.MARINE...
DISCONTINUING SCA AT 330 AM. SUB SCA CONDITIONS THROUGH TONIGHT
WITH NORTHWEST TO NORTHEAST WINDS THIS MORNING BECOMING WESTERLY
MIDDAY THEN SEA BREEZES DURING LATE AFTERNOON. LIGHT WINDS TONIGHT
BECOMING N-NE LATE.

OUTLOOK...
SUNDAY/SUNDAY NIGHT...SUB-SCA CONDITIONS. RAIN SOUTH.
MONDAY/MONDAY NIGHT...MOSTLY AUB-ACA BUT SOME WIND GUSTS AROUND 25
 KTS POSSIBLE. SCATTERED SHOWERS.
TUE THRU WED...MOSTLY SUB SCA.

&&

.FIRE WEATHER...
DRY CONDITIONS ARE EXPECTED ONCE AGAIN TODAY, WITH MINIMUM RH
VALUES ONCE AGAIN RANGING FROM 20 TO 30 PERCENT. HOWEVER, WINDS
WILL BE CONSIDERABLY LIGHTER, WITH GUSTS GENERALLY NEAR OR BELOW
15 MPH THROUGH THE DAY.  NO ACTION ATTM.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...FREEZE WARNING UNTIL 8 AM EDT THIS MORNING FOR PAZ060>062-
     101>106.
     FROST ADVISORY UNTIL 8 AM EDT THIS MORNING FOR PAZ070-071.
NJ...FREEZE WARNING UNTIL 8 AM EDT THIS MORNING FOR NJZ001-007>010-
     012-013-015>022-027.
     FROST ADVISORY UNTIL 8 AM EDT THIS MORNING FOR NJZ014-023>026.
DE...FROST ADVISORY UNTIL 8 AM EDT THIS MORNING FOR DEZ001>004.
MD...FREEZE WARNING UNTIL 8 AM EDT THIS MORNING FOR MDZ008.
     FROST ADVISORY UNTIL 8 AM EDT THIS MORNING FOR MDZ012-015-019-
     020.
MARINE...NONE.

&&

$$
SYNOPSIS...O`HARA
NEAR TERM...DRAG
SHORT TERM...DRAG
LONG TERM...O`HARA
AVIATION...DRAG/O`HARA
MARINE...DRAG/O`HARA
FIRE WEATHER...



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.