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 011347
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
947 AM EDT TUE SEP 1 2015

.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE MID-ATLANTIC AREA THROUGH
MIDWEEK. A WEAK BACKDOOR COLD FRONT WILL MOVE SOUTHWARD INTO OUR
REGION THURSDAY INTO FRIDAY. THEN, ANOTHER LARGE HIGH PRESSURE
SYSTEM SETS UP ACROSS THE NORTHEASTERN UNITED STATES THROUGH THE
WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CURRENT FORECAST ON TRACK WITH ONLY MINOR ADJUSTMENTS.

EARLY MORNING FOG IS DISSIPATING ATTM AS BOUNDARY LAYER MIXING
GETS UNDERWAY. WATER VAPOR IMAGERY INDICATES A SUBTLE SHORTWAVE
MOVING THRU THE MID-LEVEL RIDGE TODAY...W/SURFACE HIGH PRESSURE
CENTERED OVER THE SPINE OF THE APPALACHIANS...AND A WEAK TROUGH
IN THE DELAWARE VALLEY. THE IAD AND WAL 12Z SOUNDINGS INDICATE A
DRY COLUMN WHICH WILL CONTINUE THRU THE DAY. THE WEAK PRESSURE
GRADIENT WILL PROMOTE A SEA-BREEZE ACROSS COASTAL LOCALS THIS
AFTERNOON. THIS WILL LEAD TO A BIT MORE HUMIDITY MOVING JUST
INLAND FROM THE COAST AND HELP FOCUS MOISTURE CONVERGENCE...
BUT EXCEPT FOR SOME MORE ROBUST CU...DO NOT EXPECT ANY PRECIP.

12Z SOUNDINGS INDICATE MIXING POTENTIAL TO 800 HPA TODAY...
AND SUPPORT HIGHS GENERALLY IN THE U80S TO L90S BUT COOLER
NEAR THE COAST WITH A SEA-BREEZE. ALSO...RELATIVE HUMIDITY
VALUES WILL BE LOW ENOUGH TO PRECLUDE HEAT INDEX VALUES FROM
ADVISORY CRITERIA LEVELS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
TONIGHT SHOULD BE A CARBON COPY OF THE LAST FEW NIGHTS, WITH ONE
POSSIBLE EXCEPTION OF INCREASING HIGH CIRRUS CLOUDS OVERNIGHT.
OTHERWISE, EXPECT RADIATIONAL COOLING TO LEAD TO LOWS NEAR THE DEW
POINT TEMPERATURES. THUS COULD ALSO SEE SOME PATCHY FOG PRIMARILY IN
RIVER VALLEYS.

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
HIGH PRESSURE WILL BE THE DOMINANT WX FEATURE FOR THE FIRST FEW
DAYS OF SEPTEMBER, ALTHOUGH THE TEMPS WILL FEEL MORE LIKE AUGUST.
HIGHS ON THU WED AND THU WILL BE ABOUT 10 DEGREES ABV NRML, AND
WITH DEW POINTS IN THE MID TO UPPER 60S, IT WILL BE LESS THAN
IDEAL.

HOWEVER, BY THU AND FRI A BACKDOOR CDFNT WILL MOVE THRU THE REGION
AND BRING AT LEAST A CHC OF SOME PRECIP. WE HAVEN`T SEEN MUCH IN
THE WAY OF RAIN LATELY, SO ANY IS WELCOME. QPF AMTS ARE LOW AND
MANY AREAS WILL REMAIN DRY. HOWEVER, BEHIND THIS FRONT, TEMPS WILL
BE MUCH COOLER (CLOSER TO SEASONAL) AND IT LOOKS LIKE WE HAVE A
BEAUTIFUL HOLIDAY WEEKEND IN STORE. HIGH PRES WILL BUILD BACK IN
AND BRING ABUNDANT SUNSHINE AND LOWER HUMIDITY. SAT CUD BE A TAD
BREEZY, ESPECIALLY CLOSER TO THE CST, BUT THAT SHUD BE THE WORST
WE WILL HAVE TO DEAL WITH.

&&

.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY, AND SURROUNDING AREAS.

VFR CONDITIONS ARE EXPECTED TODAY. A ROUND OF MVFR FOG IS
POSSIBLE AFTER 03Z TONIGHT. AT THIS POINT, THE TAF SITES THAT ARE
THE MOST LIKELY TO BE AFFECTED ARE KMIV, KACY, KRDG, KTTN, AND
KABE.

NORTH TO NORTHWEST WINDS SHOULD REMAIN LIGHT (LESS THAN 10 KT).
WITH THE UPPER LEVEL RIDGE MOVING OVERHEAD, IT LOOKS TO BE A PRIME
SET UP FOR A WELL DEVELOPED SEA BREEZE THIS AFTERNOON. THUS HAVE
INCLUDED A SHIFT TO SOUTHEASTERLY NOT ONLY AT THE COASTAL (KACY
AND KMIV) AND DELAWARE VALLEY TAF SITES (KPHL, KPNE, KTTN, AND
KILG). THE SEA BREEZE SHOULD DISSIPATE NEAR OR SHORTLY AFTER
SUNSET, LEADING TO MOSTLY LIGHT AND VARIABLE WINDS OVERNIGHT.

OUTLOOK...

WED...MAINLY VFR CONDS EXPECTED. SOME MORNING FOG/STRATUS
PSBL MVFR.  HIGH CONFIDENCE.

THU THROUGH FRI...MAINLY VFR. HOWEVER, SHRA/TSRA ARE PSBL, WITH
PERIODS OF SUB-VFR CONDITIONS. THERE CUD ALSO BE SOME FOG AS A
CDFNT MOVES THRU THE REGION. MDT TO HIGH CONFIDENCE.

SAT...VFR CONDS EXPECTED.  HIGH CONFIDENCE.

&&

.MARINE...
WINDS AND SEAS SHOULD REMAIN WELL BELOW SMALL CRAFT ADVISORY
CRITERIA, WITH PEAK WIND GUSTS ONLY EXPECTED TO BE NEAR 15KT, AND
SEAS SHOULD STAY AROUND OR BELOW 2 FT.

OUTLOOK...

WED THROUGH THU...NO MARINE FLAGS ANTICIPATED. SEAS 2 TO 3 FEET
WITH SOUTHERLY WINDS 5 TO 10 KNOTS, SOME GUSTS NEAR 15 KNOTS.

FRI THRU SAT...WIND BECOMES MORE ENELY AND INCREASES AS A BACKDOOR
CDFNT MOVES THRU THE REGION. SEAS WILL RISE AND THEY COULD
APPROACH 5 FEET BY LATE FRI, THEN DECREASING BY LATER SAT. WIND
CUD GUST 25 TO 30 KT FRI INTO SAT. BY LATER SAT, CONDS SHUD DROP
BELOW SCA CRITERIA.

&&

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

&&

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


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