Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000
FXUS61 KPHI 200138
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
938 PM EDT TUE AUG 19 2014

.SYNOPSIS...
A FRONTAL BOUNDARY WILL REMAIN WELL TO OUR SOUTH AND WEST FOR THE
NEXT SEVERAL DAYS. SURFACE LOW PRESSURE AND AN ASSOCIATED LOW
ALOFT WILL MOVE SOUTHEASTWARD FROM THE GREAT LAKES ON THURSDAY INTO
FRIDAY BRINGING A GOOD CHANCE FOR SHOWERS AND A FEW THUNDERSTORMS.
A RIDGE OF HIGH PRESSURE WILL THEN BECOME ESTABLISHED OVER THE
REGION AND BRING MAINLY FAIR WEATHER FOR THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
LOW PRESSURE WAS LOCATED WELL OFF THE VIRGINIA COAST THIS
EVENING. IT WILL CONTINUE TO DRIFT OUT TO SEA. MEANWHILE, A
SURFACE RIDGE EXTENDED ALONG THE APPALACHIANS.

WE ARE ANTICIPATING A PARTLY TO MOSTLY CLOUDY SKY OVERNIGHT,
ALONG WITH A LIGHT WIND. THE WIND DIRECTION WILL FAVOR EAST TO
SOUTHEAST. THE CLOUD COVER SHOULD PREVENT TEMPERATURES FROM
FALLING BELOW THE 60S AT MOST LOCATIONS.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
THE EASTERLY, ONSHORE FLOW IS FORECAST TO CONTINUE ACROSS THE
REGION THROUGH WEDNESDAY AS WEAK LOW PRESSURE WILL SLOWLY EDGE
FARTHER EAST AND AWAY FROM THE COAST, WITH WEAK HIGH PRESSURE
REMAINING SITUATED ACROSS PORTIONS OF NEW ENGLAND. THE NEXT
FEATURE OF INTEREST WILL BE A MID-LEVEL SHORTWAVE PROGRESSING
EASTWARD FROM THE LOWER GREAT LAKES/UPPER OHIO VALLEY REGION
ACROSS CENTRAL PA THROUGH THE DAYTIME WEDNESDAY. THERE IS FAIRLY
GOOD MODEL AGREEMENT BETWEEN THE GFS, NAM, AND ECMWF WITH REGARDS
TO THIS SHORTWAVE REMAINING OFF TO OUR WEST THROUGH THE DAYTIME
AND THUS HOLDING MOST PRECIP CHANCES FOR OUR WESTERN ZONES UNTIL
LATER WEDNESDAY EVENING/NIGHT, AND WE HAVE ONLY SOME LOW POPS FOR
ISOLATED ACTIVITY INTO THE EVENING.

FOR HIGH TEMPERATURES WEDNESDAY, WE MAINLY TOOK A MET/MAV BLEND,
BUT THEN EDGED MAX TEMPERATURES DOWN A DEGREE OR TWO ALONG THE
COAST WITH THE PERSISTENT ONSHORE FLOW. MAXIMUM TEMPERATURES
SHOULD MOSTLY RANGE FROM THE UPPER 70S ALONG THE COAST AND IN THE
SOUTHERN POCONOS TO THE LOWER 80S ELSEWHERE.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
AN OVERALL RATHER BENIGN AUGUST WEATHER PATTERN WILL CONTINUE FOR
THE MID-ATLANTIC REGION FOR THE NEXT SEVERAL DAYS. AN UPPER LOW
NOW OVER THE WESTERN GRTLKS IS FORECAST TO WEAKEN AS IT MOVES
SOUTHEAST ACROSS THE LOWER GRTLKS AND NY STATE DURING THURSDAY AND
FRIDAY...THEN REDEVELOPING SOMEWHAT EAST OF NEW ENGLAND OVER THE
WEEKEND. MEANWHILE AN UPPER LEVEL RIDGE IS FORECAST TO BUILD OVER
THE MS VALLEY...RESULTING IN CONFLUENT/SUBSIDENT FLOW OVER THE
REGION FOR MOST OF THE WEEKEND INTO EARLY NEXT WEEK.

AS THE UPPER LOW/TROF MOVE BY ON THU/FRI...THERE IS SOME FORCING
FOR UVV ALONG WITH INCREASING PW AND MODEST INSTBY. THUS A PERIOD
OF SHOWERS/TSTMS IS EXPECTED WITH HIGHEST POPS LATE THU AND THU
NIGHT. THE CHC POPS CONTINUE INTO FRI ALTHOUGH INSTBY SEEMS
MARGINAL AT THAT TIME. FOR THE WEEKEND A SURFACE HIGH PRESSURE
RIDGE IS EXPECTED TO BUILD OVER NEW ENGLAND...RESULTING IN A
SOMEWHAT COOLER AND DRIER FLOW INTO THE MID-ATLANTIC REGION.

MAX/MIN TEMPS THROUGH THE PERIOD ARE FORECAST TO REMAIN WITHIN A
FEW DEGREES OF NORMAL.

&&

.AVIATION /02Z WEDNESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD WITH ONE
EXCEPTION. SOME LIGHT FOG MAY IMPACT KRDG AND KMIV AROUND
DAYBREAK. THE CLOUD COVER WILL VARY FROM BROKEN TO SCATTERED WITH
ANY CEILINGS REMAINING AT OR ABOVE 4000 FEET.

THE WIND IS FORECAST TO REMAIN LESS THAN 10 KNOTS. THE DIRECTION
SHOULD FAVOR THE SOUTHEAST TO EAST OVERNIGHT THEN IT IS EXPECTED
TO VEER TOWARD THE SOUTHEAST AND SOUTH ON WEDNESDAY.

OUTLOOK...
WEDNESDAY NIGHT THROUGH FRIDAY...CHANCE FOR SHRA/TSRA AS A SERIES
OF DISTURBANCES MOVE THRU THE REGION. LOCAL/TEMPORARY FLIGHT MVFR
RESTRICTIONS POSSIBLE. WINDS MAINLY EAST TO SOUTHEAST.

FRIDAY NIGHT THROUGH SUNDAY...PREDOMINATELY VFR CONDITIONS WITH
NORTHEAST WINDS.

&&

.MARINE...
AN OVERALL EASTERLY TO EAST-SOUTHEAST FLOW IS EXPECTED TO
CONTINUE ACROSS OUR COASTAL WATERS AND DELAWARE BAY TONIGHT
THROUGH WEDNESDAY. WIND SPEEDS WILL MOSTLY BE IN THE 5 TO 15 KNOT
RANGE FOR OUR WATERS THROUGH THIS PERIOD, STRONGEST FOR OUR
SOUTHERN COASTAL WATERS. SEAS WILL MOSTLY BE IN THE 2 TO 4 FOOT
RANGE FOR THE COASTAL WATERS TONIGHT THROUGH WEDNESDAY, WITH 1 TO
3 FOOT SEAS FOR DELAWARE BAY.

OUTLOOK...

THURSDAY THROUGH FRIDAY...NO SCA FLAGS EXPECTED WITH WINDS/SEAS
BELOW THRESHOLDS. HOWEVER... LOCALLY ROUGH CONDS ARE POSSIBLE IN
SCATTERED SHOWERS AND THUNDERSTORMS.

SATURDAY AND SUNDAY...A PERSISTENT NORTHEAST FLOW WILL LIKELY
RESULT IN BUILDING SEAS AND GUSTY WINDS. MARGINAL SCA CONDS ARE
POSSIBLE ATTM.

&&

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

&&

$$

SYNOPSIS...AMC
NEAR TERM...IOVINO
SHORT TERM...KLINE
LONG TERM...AMC
AVIATION...AMC/IOVINO
MARINE...AMC/KLINE





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