Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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FXUS61 KPHI 021950
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
350 PM EDT THU JUL 2 2015

.SYNOPSIS...
WEAK HIGH PRESSURE WILL BUILD TO OUR NORTH TONIGHT INTO FRIDAY AS
ANOTHER WAVE OF LOW PRESSURE MOVES ALONG A STALLED FRONT TO THE
SOUTH. ANOTHER AREA OF HIGH PRESSURE WILL THEN MOVE INTO THE
REGION THROUGH THE HOLIDAY WEEKEND. A COLD FRONT WILL CROSS THE
AREA BY WEDNESDAY.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
FRONT REMAINS STALLED TO OUR SOUTH, AND WITH AN UPPER LEVEL SHORT
WAVE TROUGH LIFTING NE OVER THE REGION, WE COULD CONTINUE TO SEE
ISOLATED SCATTERED SHOWERS THROUGH THE DAY TIME HOURS. MODELS
CONTINUE TO PAINT QPF OVERNIGHT. HOWEVER, THIS SEEMS A BIT OVERDONE
AS THERE CONTINUES TO BE DRY AIR ADVECTION IN THE LOW LEVELS, NOT TO
MENTION A LACK OF UPPER LEVEL SUPPORT (SAVE FOR A BRIEF PERIOD UNDER
THE RIGHT REAR QUADRANT OF A WEAK UPPER LEVEL JET). MODELS HAVE
BACKED OFF ON ANY MID LEVEL SHORT WAVE TROUGHS AS WELL. THEREFORE
HAVE DECREASED POPS, EXCEPT IN SOUTHERN DELMARVA AS THERE CONTINUES
TO BE THE CHANCE FOR SHOWER DEVELOPMENT ALONG THE FRONT.

AS FAR AS FOG POTENTIAL, GIVEN THE LOW LEVEL DRY AIR ADVECTION, IT
WILL BE VERY DEPENDENT FIRST ON IF AND WHEN WINDS WILL SHIFT TO MORE
OF AN OFF SHORE DIRECTION. IN ADDITION, AREAS IN DELMARVA AND
SOUTHERN NJ THAT HAD RAIN TODAY MAY STILL HAVE SOME STANDING WATER
TONIGHT WHICH COULD HELP FOG DEVELOPMENT. FOR NOW, HAVE INCLUDED
PATCHY FOG GENERALLY ALONG AND SOUTH OF A MIV TO ACY LINE. HOWEVER,
WILL NOT MENTION ANY POTENTIAL FOR DENSE FOG AT THIS TIME GIVEN THE
UNCERTAINTY IN THE TIMING OF THE WIND SHIFT.


&&

.SHORT TERM /6 AM FRIDAY THROUGH 6 AM FRIDAY/...
UPPER LEVEL SHORT WAVE RIDGE MOVES OVER HEAD BRINGING MOSTLY DRY
CONDITIONS, ALTHOUGH STILL A FEW SHOWERS MAY DEVELOP ALONG THE OLD
FRONTAL BOUNDARY AND MOVE NORTHEAST INTO OUR REGION. EVEN THOUGH
THERE SHOULD BE LESS CLOUDS TOMORROW (ESPECIALLY IN THE NORTHWEST),
STILL EXPECT TEMPERATURES TO BE SLIGHTLY BELOW NORMAL GIVEN THE
RELATIVELY COOL AIR MASS STILL IN PLACE.


&&

.LONG TERM /FRIDAY THROUGH THURSDAY/...
FOR THE START OF THE EXTENDD PD, A STALLED FRONT WILL BE LOCATED S
OF THE REGION. LOW PRES IS EXPECTED TO MOV ALG THE FRONT AND CUD
TRIGGER SOME SHRA/TSRA SAT INTO SAT EVE. THE BEST CHCS ARE OVER
SRN AREA. IT STILL APPEARS THAT ANY ACTIVITY SHUD BE SCT AND OVER
WITH BY SUNSET OR SHORTLY THEREAFTER. SAT LOOKS TO BE THE WORST OF
THE TWO WEEKEND DAYS, IF WE HAD TO PICK ONE.

BY SUN, HIGH PRES BEGINS TO BUILD IN AND SUN SHUD BE DRY OVER
MOST, IF NOT ALL OF THE AREA, CONTINUING INTO SUN NIGHT.

THE MDLS HAVE SOME DISAGREEMENT AS WE MOVE INTO MON. THE GFS IS
DRY. THE CMC IS ALSO DRY. THE ECMWF TRIES TO DEVELOP ANOTHER WAVE
OF LOW PRES AND IS SUBSEQUENTLY WETTER THAN THE OTHER MDLS. RIGHT
NOW, THE ECMWF IS THE OUTLIER. BUT, FELT COMPELLED TO AT LEAST
INTRODUCE SOME VERY LOW POPS. HOWEVER, CONFIDENCE IS VERY LOW. THE
ECMWF KEEPS THINGS WET INTO TUE WHILE THE OTHER MDLS ARE DRY.

THEN, BY WED, MDLS COME INTO BETTER AGREEMENT AGAIN AS A CDFNT
APPROACHES FROM THE W, PRECIP WOULD PROB LINGER INTO THU, BUT
THERE IS STILL A WEEK FOR THE MDLS TO IRON OUT ANY DIFFS IN
FRONTAL TIMING.

WITH THE EXCEPTION OF SAT, WHICH LOOKS TO BE ON THE COOL SIDE,
TEMPS SHUD BE NR OR SLIGHTLY ABV NRML THRU THE PD.

&&

.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

MOSTLY VFR CONDITIONS ARE EXPECTED THROUGH 06Z. THE ONE EXCEPTION
WILL BE UNDER ANY TRANSIENT SHOWERS WHICH COULD BRING BRIEF MVFR
CONDITIONS (OR EVEN IFR CONDITIONS FOR KMIV OR KACY). HOWEVER THE
CHANCES FOR SHOWERS WILL CONTINUE TO DECREASE THROUGH THE AFTERNOON
AND EVENING.

AFTER 06Z, BR COULD DEVELOP, BUT THERE IS CONSIDERABLE UNCERTAINTY
GIVEN DRIER AIR MOVING INTO THE REGION AND A WIND SHIFT FROM
NORTHEASTERLY TO MORE NORTHERLY (WIND SHOULD REMAIN LIGHT, GENERALLY
5 KT OR LESS THROUGH THE TAF PERIOD). FOR NOW HAVE ONLY MENTIONED
MVFR CONDITIONS AT KMIV, AND IFR CONDITIONS AT KACY, WHICH HAVE A
HIGHER RISK GIVEN SATURATED GROUND.

EXPECT TO RETURN TO VFR EVERYWHERE BY 18Z TOMORROW. THERE REMAINS A
SMALL CHANCE FOR SHOWERS, BUT TOO SMALL TO MENTION IN ANY TAFS AT
THIS TIME.


OUTLOOK...
FRI NIGHT AND SAT...GENLY VFR. HOWEVER, THERE WILL BE A CHC OF
MVFR/IFR CONDS SAT AFTN/EVE IN SCT SHWRS AND PSBL TSRA. BEST CHCS
ARE FOR THE SRN TAF SITES.  MDT CONFIDENCE.

SAT NIGHT THRU TUE...VFR CONDS EXPECTED SUN AND TUE. HIGH
CONFIDENCE. LESS CERTAINTY FOR MON, DUE TO MDL DISAGREEMENT. COULD
BE A BETTER CHANCE OF SHRA/TSRA, BUT CONFIDENCE IS MUCH LOWER.

&&

.MARINE...
WINDS AND SEAS SHOULD STAY BELOW SCA CRITERIA TONIGHT AND
TOMORROW.

OUTLOOK...
FRI NIGHT THROUGH SAT...DEPENDING ON THE STRENGTH AND TRACK OF LOW
PRES ALG STALLED FRONT, SCA MAY BE NEEDED, ESPECIALLY ON THE SRN
WATERS. HOWEVER,  LTST GUID INDICATES BOTH WIND AND SEAS WILL
REMAIN BELOW SCA CRITERIA DURG THIS PD.

SAT NIGHT THRU TUE...NO MARINE FLAGS ANTICIPATED DURG THIS PD.

&&

.TIDES/COASTAL FLOODING...
THE ONSHORE FLOW COMBINING WITH RATHER ROBUST SPRING TIDES
FOLLOWING THE FULL MOON (WHICH OCCURRED THIS PAST WEDNESDAY) MIGHT
CAUSE MINOR TIDAL FLOODING WITH THE EVENING HIGH TIDE CYCLES ON
FRIDAY (THE MORE LIKELY ONE) AND SATURDAY. HOWEVER, LTST GUID
INDICATES WE SHUD STAY JUST BELOW MINOR TIDAL FLOODING CRITERIA
ATTM.

&&

.RIP CURRENTS...
THE COMBINATION OF AN ONSHORE FLOW AND THE FULL MOON IS EXPECTED
TO INCREASE THE STRENGTH OF RIP CURRENTS ON FRIDAY AND SATURDAY,
BEFORE CONDITIONS IMPROVE ON SUNDAY. WE THINK THAT ONE OR
BOTH DAYS COULD REACH MODERATE RISK LEVELS.

&&

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

&&

$$
SYNOPSIS...NIERENBERG
NEAR TERM...JOHNSON
SHORT TERM...JOHNSON
LONG TERM...NIERENBERG
AVIATION...JOHNSON/NIERENBERG
MARINE...JOHNSON/NIERENBERG
TIDES/COASTAL FLOODING...
RIP CURRENTS...


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