Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000
FXUS61 KPHI 030355
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1155 PM EDT TUE JUN 2 2015

.SYNOPSIS...
A FRONTAL BOUNDARY WILL STALL SOUTH OF THE AREA THROUGH FRIDAY.
MEANWHILE, HIGH PRESSURE WILL PASS TO OUR NORTH OVERNIGHT AND
WEDNESDAY BEFORE MOVING OFF THE NEW ENGLAND COAST LATE IN THE
WEEK. A COLD FRONT WILL PROGRESS SOUTHWARD THROUGH THE AREA FRIDAY
NIGHT INTO SATURDAY. ANOTHER AREA OF HIGH PRESSURE WILL BUILD INTO
THE REGION SATURDAY NIGHT BEFORE MOVING OFFSHORE SUNDAY. A WARM
FRONT MOVING INTO THE AREA MONDAY WILL BE FOLLOWED BY THE PASSAGE
OF A COLD FRONT ON TUESDAY.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
RAIN CONTINUED TO FALL IN MUCH OF CENTRAL AND SOUTHERN NEW JERSEY
AROUND MIDNIGHT. AREAS OF LIGHT RAIN WERE LOCATED IN PARTS OF
SOUTHEASTERN PENNSYLVANIA, DELAWARE AND NORTHEASTERN MARYLAND, AS
WELL. THE RAIN APPEARED TO BE ENHANCED BY A SLOW MOVING WEAK
IMPULSE TRAVELING IN THE MID LEVEL FLOW.

DRYING WILL CONTINUE TO WORK ITS WAY INTO OUR REGION FROM THE
NORTH AND WEST DURING THE NIGHT. THE COVERAGE OF THE RAIN WILL
DECREASE. HOWEVER, THE SKY SHOULD REMAIN OVERCAST.

A NORTHEAST WIND WILL PERSIST OVERNIGHT. SPEEDS ARE FORECAST TO
BE AROUND 8 TO 14 MPH ON THE COASTAL PLAIN, AND ABOUT 4 TO 8 MPH
INLAND. TEMPERATURES SHOULD STAY MAINLY IN THE 50S.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
LOW CLOUDS, DRIZZLE AND LIGHT RAIN SHOWERS WILL STILL BE IN PLACE
THROUGH MOST OF THE DAY. THESE CONDITIONS WILL HANG ON LONGEST
ACROSS THE DELMARVA, CLOSEST THE FRONT. SOME BREAKS IN THE CLOUDS
MAY OCCUR LATER IN THE DAY THE FURTHER NORTH YOU GO. THIS WILL
LIKELY LEAD TO AN UNUSUAL TEMPERATURE SPREAD ACROSS THE REGION
WITH THE HIGHEST READINGS IN THE UPPER 60`S ACROSS THE NORTH WHERE
MORE SOLAR RADIATION CAN COME COME THROUGH AND COOLER TEMPERATURES
ACROSS THE DELMARVA. PHILADELPHIA METRO COULD ACTUALLY GO EITHER
WAY, TOOK A MIDDLE APPROACH BETWEEN THE COOLER, WETTER FURTHER
NORTH NAM AND THE DRIER, WARMER ECMWF FOR THE PHILADELPHIA METRO.
QPF SHOULD BE LIGHT UNDER 1/10TH OF AN INCH.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
THE CUTOFF LOW OVER THE SOUTHERN APPALACHIANS WEDNESDAY NIGHT IS
FORECAST TO BECOME AN OPEN WAVE AS IT MOVES EASTWARD TOWARD THE
CAROLINAS THROUGH THURSDAY NIGHT. THE SURFACE REFLECTION OF THIS
LOW WILL BE MARKED BY AN INVERTED TROUGH ALONG THE SOUTHEAST
COAST. THIS TROUGH IS EXPECTED TO EXTEND NORTHEASTWARD TO 50 MILES
OR SO OFF THE DELMARVA COAST. THIS SURFACE TROUGH, WHICH IS
ASSOCIATED WITH AN OLD FRONTAL BOUNDARY THAT MOVED THROUGH THE
AREA EARLIER IN THE WEEK, IS EXPECTED TO REMAIN NEARLY STATIONARY
TO OUR SOUTH AND EAST. MEANWHILE, THE FORECAST AREA WILL REMAIN
STUCK IN A HYBRID COLD-AIR DAMMING (CAD) LIKE SETUP TO THE
NORTHWEST OF THIS BOUNDARY. ALTHOUGH THE CENTER OF THE HIGH WILL
BE MOVING OFF THE NEW ENGLAND COAST (WHICH IS NOT AN IDEAL CAD
POSITION), THE POCKET OF COLDER AIR NEAR THE SURFACE WILL BE
REINFORCED BY EAST-NORTHEAST FLOW OFF THE ATLANTIC WATERS AND BY
DIABATIC COOLING. THIS SETUP WILL PROLONGED OUR STRETCH OF
SEASONABLY COOL, CLOUDY AND DAMP CONDITIONS INTO FRIDAY MORNING.
HIGHEST COVERAGE OF SHOWERS ARE EXPECTED WEDNESDAY NIGHT/THURSDAY
MORNING IN CONJUNCTION WITH THE LOW-LEVEL TROUGH LIFTING NORTHWARD
THROUGH THE NORTHERN MID-ATLANTIC STATES. POPS WERE INCREASED TO
LIKELY FOR A MAJORITY OF THE FORECAST AREA DURING THIS TIME.

THE UPPER LOW AND INVERTED SURFACE TROUGH WILL MOVE FARTHER OFF
THE EAST COAST FRIDAY AFTERNOON AND NIGHT. WE WILL LOSE THE
ONSHORE FLOW AS WINDS BACK OUT OF THE NORTH AND EVEN BECOME
LIGHT/VARIABLE AT THE SURFACE. THE TEMP FORECAST FOR FRIDAY IS
TRICKY AS THE DIFFERENCE THIS TIME OF YEAR BETWEEN HIGHS IN THE
LOW 70S VS LOW 80S CAN BE AS LITTLE AS AN HOUR OR TWO OF SUNSHINE.
OFFICIAL FORECAST SIDES CLOSER TO THE WARMER MAX TEMP GUIDANCE
GIVEN THE OPPORTUNITY FOR BREAKS IN THE CLOUDS FRIDAY AFTERNOON.

A COLD FRONT IS FORECAST TO WEAKEN AS IT DROPS SOUTHWARD INTO THE
AREA FRIDAY NIGHT AND SATURDAY. COVERAGE OF SHOWERS SHOULD BE LOW
(20-30 POPS) DURING THIS TIME SINCE FORCING FOR ASCENT APPEARS TO
BE LIMITED WITH THIS SYSTEM. THE OPERATIONAL GFS AND SEVERAL OF
ITS GEFS MEMBERS HAVE EVEN TRENDED DRY WITH THE FROPA WITH THE
LATEST 12Z RUN. HIGH PRESSURE QUICKLY BUILDS IN FROM THE NORTH
BEHIND THE FRONT.

THE CENTER OF THE HIGH WILL START TO MOVE THE NEW ENGLAND COAST
ON SUNDAY. KEPT THE FORECAST DRY FOR SUNDAY AS THERE SHOULD BE
ENOUGH SUBSIDENCE UNDERNEATH THE RIDGE TO CAP DEEPER CONVECTION
FROM DEVELOPING.

SOUTHERLY RETURN AROUND THE WESTERN PERIPHERY OF THE OFFSHORE
HIGH AND AHEAD OF A COLD FRONT APPROACHING FROM THE WEST WILL
STRENGTHEN ALONG THE EASTERN SEABOARD, RESULTING IN A WARMING
TREND EARLY NEXT WEEK. THE HEART OF THE WARMER AIR IS EXPECTED TO
ARRIVE AFTER A WARM FRONT LIFTS NORTHEASTWARD THROUGH THE AREA
DURING THE DAY MONDAY. THERE WILL ALSO BE A CHANCE FOR SHOWERS AND
STORMS MONDAY AND TUESDAY.

&&

.AVIATION /04Z WEDNESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

WE HAVE GONE ALONG WITH THE GUIDANCE WHICH MOSTLY SHOWS IFR
CONDITIONS ACROSS MOST AREAS OVERNIGHT. SHOWERS/FOG AND LOW CLOUDS
OVER ALL AREAS...EXCEPT NO PRECIP KRDG/KABE. VSBYS WILL SLOWLY
IMPROVE WED MORNING...FOLLOWED BY CIGS LATER. EARLIEST IMPROVEMENT
N/W WITH TIMING TO VFR DURING THE AFTERNOON FOR THE DEL VALLEY
S/E.

OUTLOOK...
WEDNESDAY NIGHT THROUGH FRIDAY MORNING...CIGS EXPECTED TO LOWER
FROM SOUTH TO NORTH TO MVFR WED NIGHT AND THU MRNG IN CONJUNCTION
WITH THE ARRIVAL OF SHRA AND STRENGTHENING ONSHORE FLOW. IFR CIGS
MAY DEVELOP, ESPECIALLY AT ACY (WHERE THE INFLUENCE OF THE MARINE
LAYER IS GREATEST). SREF PROBABILITIES FOR CIGS BELOW 1 KFT AT 12Z
THU ARE AROUND 33 PERCENT. EVEN IF CIGS BRIEFLY IMPROVE THU
AFTERNOON, THEY ARE EXPECTED TO LOWER AGAIN THU NGT. MVFR CIGS
INLAND AND IFR CIGS CLOSER TO THE COAST IS THE MOST LIKELY
OUTCOME.

FRIDAY AFTERNOON THROUGH SUNDAY...MVFR CIGS EXPECTED TO IMPROVE
TO VFR FRIDAY AFTERNOON. PREDOMINATELY VFR THRU THE WEEKEND THOUGH
THERE WILL BE A CHANCE OF SHOWERS.

&&

.MARINE...
CONTINUING WITH THE SCA ON THE COASTAL ZONES AS SEAS REMAIN NEAR
OR OR OVER FIVE FEET. SEAS WILL LIKELY BE CLOSE OR OVER FIVE FEET
THROUGH WEDNESDAY. NORTHEAST WIND GUSTS WILL INCREASE TO BETWEEN
25 AND 30 KNOTS TONIGHT AND CONTINUE THROUGH WEDNESDAY. WAVEWATCH
MAY END UP A FOOT LOW WITH SEAS IN THIS PERIOD DUE TO ONSHORE FLOW
WHICH HAS BEEN REFLECTED IN THIS FORECAST.

OUTLOOK...
WEDNESDAY NIGHT AND THURSDAY....EAST WINDS 15-20 KT WITH A
OCCASIONAL GUSTS TO 25 KT IN OUR COASTAL ATLANTIC WATERS WEDNESDAY
NIGHT WHILE SEAS ARE PREDICTED TO REMAIN AROUND 4-6 FT. HAD ENOUGH
SUPPORT FROM GUIDANCE TO EXTEND THE SCA INTO WEDNESDAY NIGHT.
EASTERLY WINDS WILL SUBSIDE THURSDAY BUT SEAS WILL STILL REMAIN
ELEVATED TO NEAR SCA THRESHOLD OF 5 FT.

THURSDAY NIGHT THROUGH SUNDAY...WINDS SHOULD REMAIN BELOW SCA
CRITERIA. SEAS SHOULD GENERALLY BE BELOW SCA CRITERIA TOO ALTHOUGH
IT MAY INCREASE TO 4 TO PERHAPS NEAR 5 FT AT TIMES THIS WEEKEND.

&&

.RIP CURRENTS...
DUE TO THE CONTINUED NORTHEAST WIND AND TODAY`S FULL MOON, WE
WILL CARRY A MODERATE RISK OF RIP CURRENTS FOR WEDNESDAY.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT THURSDAY FOR ANZ430-431-
     450>455.

&&

$$

SYNOPSIS...KLEIN
NEAR TERM...IOVINO
SHORT TERM...GAINES
LONG TERM...KLEIN
AVIATION...GAINES/KLEIN
MARINE...GAINES/KLEIN
RIP CURRENTS...PO



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