Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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763
FXUS61 KPHI 301932
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
332 PM EDT SAT APR 30 2016

.SYNOPSIS...
WEAK HIGH PRESSURE WILL BE ACROSS THE REGION EARLY TONIGHT. THE HIGH
WILL THEN MOVE OFFSHORE AS LOW PRESSURE ADVANCES UP THE OHIO VALLEY.
THIS LOW WILL AFFECT OUR WEATHER FOR SUNDAY AND INTO MONDAY. HIGH
PRESSURE WILL EXTEND ACROSS THE AREA LATER MONDAY INTO TUESDAY. MORE
LOW PRESSURE WILL MOVE TOWARDS THE AREA FOR THE MIDDLE AND END OF
THE UPCOMING WEEK BRINGING UNSETTLED WEATHER TO THE REGION.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
LOW PRESSURE WILL TRACK NORTHEAST ALONG A FRONTAL BOUNDARY FROM THE
OHIO VALLEY INTO THE GREAT LAKES KEEPING MOSTLY CLOUDY SKIES IN
PLACE TONIGHT. MOISTURE WILL LIFT ALONG AND OVERRUN THE BOUNDARY
RESULTING IN RAIN DEVELOPING TO OUR WEST OVERNIGHT. IT LOOKS TO BE
MAINLY DRY FOR THE OVERNIGHT WITH LIGHT RAIN SPREADING INTO EASTERN
PENNSYLVANIA AND THE DELMARVA BY SUNRISE. ANY QPF LOOKS TO BE UNDER
1/10TH OF AN INCH. LOWS WILL LIKELY FALL INTO THE 40`S WITH MOST OF
THE DROP IN TEMPERATURES DURING THE EVENING HOURS. DID NOT DEVIATE
MUCH FROM MET/MAV/LAV GUIDANCES IN THIS PERIOD. WINDS WILL BE UNDER
10 MPH FROM THE EAST AND SOUTHEAST.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
AN AREA OF LOW PRESSURE WILL CONTINUE TO TRACK EASTWARD INTO THE
REGION ALONG A WARM FRONTAL BOUNDARY IN THE SOUTHERN DELMARVA.
MOISTURE OVERRUNNING THE BOUNDARY WILL LEAD TO CONTINUED PERIODS OF
LIGHT TO MODERATE RAIN ACROSS MOST OF THE REGION THROUGHOUT THE DAY
ON SUNDAY. ENOUGH INSTABILITY MAY ADVECT IN JUST SOUTH OF THE WARM
FRONT FOR AN ISOLATED THUNDERSTORM AS WELL. A GRADIENT IN
TEMPERATURES IS EXPECTED AS WELL WITH THE FRONT IN THE REGION. MANY
LOCALES NORTH OF PHILADELPHIA ARE LIKELY TO BE SEVERAL DEGREES
COOLER THAN MAV/MET GUIDANCE IN THE 40`S TO LOW 50`S. ON THE
OTHER HAND, SOUTH OF THE FRONT HIGHS SHOULD GET INTO THE 60`S.
CONTINUED WINDS FROM THE EAST AND SOUTHEAST UNDER 10 MPH. THE SREF
PLUMES ARE FOR THE MOST PART TIGHTLY CLUSTERED AROUND 1/2 INCH TO
3/4 OF AN INCH OF NEEDED RAINFALL, COMPONENTS OF WPC QPF ALONG
WITH THE WRF- ARW AND NMM WERE ADDED FOR THE QPF FORECAST.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
TEMPERATURES WILL RUN 2 TO 4 DEGREES BELOW NORMAL DURING THIS TIME
PERIOD.  ONE STORM SYSTEM WILL BE IMPACTING THE REGION AT THE START
OF THIS TIME PERIOD WITH ANOTHER STORM SYSTEM EXPECTED TO AFFECT THE
REGION LATE NEXT WEEK.  BETWEEN THIS TWO STORM EVENTS, A FRONTAL
BOUNDARY WILL LINGER CLOSE TO THE AREA, RESULTING IN GENERALLY
UNSETTLED CONDITIONS THROUGH THIS TIME PERIOD.

12Z SUPERBLEND WAS USED AS PRIMARY GUIDANCE DURING THIS TIME PERIOD.
SOME ADJUSTMENTS WERE MADE TO THE COASTAL WATERS FORECAST FOR SUNDAY
NIGHT FOR BETTER CONSISTENCY WITH ADJACENT OFFICES AND
CONTINUITY.


&&

.AVIATION /19Z SATURDAY THROUGH THURSDAY/...

THE EVENING WILL START OUT WITH VFR CEILINGS. HOWEVER, WITH THE
APPROACH OF A LOW PRESSURE SYSTEM RAIN WILL DEVELOP FROM WEST TO
EAST TOWARD SUNRISE. CEILINGS AND VSBYS WILL GRADUALLY LOWER AS
WELL, REACHING IFR AROUND 12Z SUNDAY. SOME UNCERTAINTY IS STILL
PRESENT IN HOW QUICK THE CEILINGS WILL LOWER. A HIGHER DEGREE OF
CONFIDENCE IS PRESENT FOR A WINDOW OF IFR CEILINGS CENTERED AROUND
THE HEAVIEST RAINFALL IN THE MORNING AND EARLY AFTERNOON HOURS ON
SUNDAY.

OUTLOOK...
SUNDAY NIGHT THRU MONDAY...WIDESPREAD IFR/MVFR WITH FREQUENT RAINS
AND AREAS OF FOG.

MONDAY NIGHT THRU WED...VFR MOSTLY. LOWER CONDITIONS WITH OVERNIGHT
FOG POSSIBLE.

THU...INCREASING RISK OF MVFR AS RAIN MOVES BACK INTO THE AREA.

&&

.MARINE...
WITH A PERSISTENT ONSHORE SWELL, SEAS HAVE BEEN VERY SLOW TO FALL
THIS AFTERNOON. BUOY 44009 STILL HAS SEAS AROUND SIX FEET, WHILE
BUOY 44065 SEAS HAVE LOWERED TO JUST OVER FIVE FEET ON THE OCEAN.
GIVEN THE MUCH SLOWER DECREASE THAN WHAT WAVEWATCH GUIDANCE HAS, THE
SCA ON THE OCEAN HAS BEEN EXTENDED TILL 09Z FOR SEAS EXPECTED TO BE
BETWEEN FIVE AND SIX FEET. WINDS WILL BE OUT OF THE SOUTHEAST AROUND
10 KNOTS BOTH TONIGHT AND SUNDAY, WITH SOME HIGHER GUSTS UP TO 20
KNOTS IN THE AFTERNOON.

OUTLOOK...
SUN NIGHT THRU MON NIGHT...SCA CONDITIONS EXPECTED ON THE
OCEAN WATERS DUE TO SEAS.

TUE THRU THU...MOSTLY SUB SCA.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 5 AM EDT SUNDAY
     FOR ANZ450>455.

&&

$$
SYNOPSIS...SZATKOWSKI
NEAR TERM...GAINES
SHORT TERM...GAINES
LONG TERM...SZATKOWSKI
AVIATION...GAINES
MARINE...GAINES/SZATKOWSKI



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