Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000
FXUS61 KPHI 041944
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
344 PM EDT WED MAY 4 2016

.SYNOPSIS...
A TROUGH OF LOW PRESSURE WILL EXTEND EASTWARD FROM THE OHIO VALLEY
TO THE MID-ATLANTIC COASTLINE TONIGHT. DUEL LOW PRESSURE SYSTEMS
LOCATED JUST OFFSHORE AND ACROSS THE OHIO VALLEY WILL BE SLOW TO
MOVE THROUGH THE REGION FOR THE LATER HALF OF THIS WEEK. A LOW
PRESSURE SYSTEM IS LIKELY TO LINGER JUST OFFSHORE INTO THE WEEKEND.
BY SUNDAY, A COLD FRONTAL BOUNDARY IS EXPECTED TO MOVE SOUTHEAST
THROUGH THE REGION. THIS WILL BE FOLLOWED BY WELCOMED HIGH PRESSURE
BUILDING NORTHEAST INTO THE REGION FOR THE FIRST PART OF NEXT
WEEK.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
A MID LEVEL SHORT WAVE TROUGH WAS LIFTING NORTHEASTWARD OVER OUR
REGION THIS AFTERNOON. IT HELPED TO DEVELOP THE AREA OF SHOWERS AND
EMBEDDED THUNDERSTORMS THAT PASSED ACROSS OUR COASTAL PLAIN. THE
AREA OF PRECIPITATION SHOULD BE NORTHEAST OF OUR FORECAST AREA BY
600 PM.

LOW PRESSURE WILL REMAIN ALONG AND OFF THE MIDDLE ATLANTIC COAST
TONIGHT.

ANOTHER AREA OF LOW PRESSURE WAS CENTERED OVER SOUTHEASTERN
MICHIGAN AT MID AFTERNOON. THE LOW WILL SHIFT SOUTHEASTWARD AND
IT IS EXPECTED TO MERGE WITH THE COASTAL LOW LATE TONIGHT.

THE SURFACE WEATHER PATTERN IS EXPECTED TO MAINTAIN A NORTHEAST FLOW
IN OUR REGION. AS A RESULT, WE WILL CONTINUE TO HAVE LOW CLOUDS AND
PATCHY DRIZZLE TONIGHT ALONG WITH ISOLATED LIGHT SHOWERS. PATCHY FOG
IS POSSIBLE IN THE ELEVATED TERRAIN.

MINIMUM TEMPERATURES WILL FAVOR THE MIDDLE AND UPPER 40S.

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/...
A PRIMARY SURFACE LOW IS FORECAST TO PROGRESS NORTHEASTWARD TO THE
WATERS OFF NEW ENGLAND ON THURSDAY. MEANWHILE, A LINGERING AREA OF
LOW PRESSURE SHOULD REMAIN OFF THE MIDDLE ATLANTIC COAST. AS A
RESULT, WE WILL EXPERIENCE ANOTHER DAY OF NORTHEASTERLY WIND ALONG
WITH LOW CLOUDS. SCATTERED SHOWERS ARE POSSIBLE, MAINLY IN OUR
NORTHWESTERN COUNTIES.

MAXIMUM TEMPERATURES ARE ANTICIPATED TO BE IN THE 50S.

&&

.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
THURSDAY NIGHT THROUGH SATURDAY: DUAL LOW PRESSURES WILL CONTINUE
THE GRAY AND DREARY PATTERN ACROSS THE REGION IN THIS TIMEFRAME. THE
FIRST AREA OF LOW PRESSURE WILL LIKELY BE DEPARTING TO THE NORTHEAST
OFF CAPE COD WITH THE SECOND LOW PRESSURE SYSTEM IN THE CAROLINAS.
THESE LOW PRESSURE SYSTEMS WILL PROVIDE LIFT AND MOISTURE WITH
ONSHORE FLOW LEADING TO ADDITIONAL PERIODS OF SHOWERS. THE HIGHEST
CHANCES CURRENTLY ARE LIKELY TO OCCUR ON FRIDAY WHEN THE TRAILING
LOW PRESSURE SYSTEMS LOCATED JUST TO OUR SOUTHWEST. RIGHT NOW
MODELING IS FOCUSING THE HEAVIEST AND STEADIEST SHOWERS ACROSS
NORTHERN PORTIONS OF THE REGION ON FRIDAY. QPF COULD REACH HALF AN
INCH BY FRIDAY NIGHT IN NORTHERN PARTS OF THE REGION. WITH THE
EXCESSIVE CLOUDCOVER IN PLACE WENT A LITTLE COOLER IN THE DAYS
WITH HIGHS THAN WHAT MET/MAV GUIDANCE WOULD SUGGEST AND WARMER AT
NIGHT,HIGHS WILL LIKELY STAY IN THE 50`S FOR MOST OF THE REGION.

THERE IS SOME OPTIMISM THAT SATURDAY AFTERNOON/EVENING COULD BE
DRIER THAN INDICATED IN THE VARIOUS ENSEMBLE PACKAGES. HOWEVER, AN
EQUAL POSSIBILITY IS PRESENT THAT THE SECOND LOW WILL LINGER
OFFSHORE THROUGH SATURDAY. THE CLOUDS AND SHOWERS SHOULD KEEP LOW
TEMPERATURES WARMER AT NIGHT AND COOLER IN THE DAY THAN WHAT VARIOUS
GUIDANCE PACKAGES INDICATE. TEMPERATURES WILL START A GRADUAL
WARMING TREND ON SATURDAY.

SATURDAY NIGHT THROUGH SUNDAY NIGHT: A COLD FRONTAL BOUNDARY WILL
LIKELY BE THE ULTIMATE KICKER FOR THE STUBBORN LOW PRESSURE JUST
OFFSHORE. HOWEVER, TIMING REMAINS UNCERTAIN AT THIS POINT. THE COLD
FRONT WILL BE A FOCUS FOR YET ADDITIONAL SCATTERED LIGHT SHOWERS LATE
SATURDAY NIGHT AND SUNDAY. A BREAK BETWEEN SYSTEMS WITH SOME
CLEARING IS LIKELY TO OCCUR BEFORE THE NEXT ROUND OF SHOWERS
ARRIVES.

MONDAY THROUGH WEDNESDAY: ON MONDAY HIGH PRESSURE WILL BUILD
NORTHEAST INTO THE REGION. THIS WILL ALLOW FOR A FEW DRY DAYS AND A
GRADUAL WARMING TREND THROUGH THE FIRST HALF OF NEXT WEEK AS A
NORTHWESTERLY FLOW GRADUALLY BECOMES SOUTHERLY BY WEDNESDAY. THE
CHALLENGE IN THIS PERIOD WILL BE A WARM FRONT DIVIDING A COOLER
MORE MARINE AIRMASS AND SOUTHERLY FLOW SENDING MORE SUMMERLIKE
TEMPERATURES INTO OUR REGION. RIGHT NOW THE LOCATION AND TIMING OF
THIS WARM FRONT EARLY NEXT WEEK IS STILL UNCERTAIN. HOWEVER, IT DOES
LOOK LIKE THE FRONT MAKES IT NORTH OF THE REGION. THIS WOULD
POTENTIALLY RESULT IN HIGH TEMPERATURES INTO THE 80`S BY WEDNESDAY.
FOR NOW, HAVE TEMPERED THIS CHANGE IN MODELING KEEPING SOME
CONTINUITY GIVEN THE UNCERTAINTY. LOW PRESSURE ALONG THE FRONT WILL
MOVE TOWARD OUR REGION ON WEDNESDAY. THERE IS A POTENTIAL FOR
OVERLAP OF INSTABILITY AND OVER 30 KNOTS OF 0-6 KM BULK SHEAR,
BUT IT`S TO EARLY TO ACCESS THE DEGREE OF ANY SEVERE WEATHER.

&&

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

THE AREA OF SHOWERS AND EMBEDDED THUNDERSTORMS ALONG THE NEW JERSEY
COAST AT MID AFTERNOON WILL CONTINUE TO MOVE AWAY TO OUR NORTHEAST.

CEILINGS ARE FORECAST TO FAVOR THE 1000 TO 1500 FOOT RANGE AT OUR
TAF SITES THROUGH THE BALANCE OF THE DAYLIGHT HOURS. CEILINGS ARE
EXPECTED TO DROP INTO THE 400 TO 800 FOOT RANGE FOR TONIGHT INTO
THURSDAY MORNING. DAYTIME HEATING SHOULD CAUSE THE CLOUD BASES TO
RISE BACK AROUND 1000 TO 1500 FEET FOR THURSDAY AFTERNOON.
VISIBILITY VALUES SHOULD REMAIN MOSTLY ABOVE 5 MILES. HOWEVER,
SCATTERED LIGHT SHOWERS AND PATCHY DRIZZLE FROM TONIGHT INTO
THURSDAY MAY BRIEFLY REDUCE THE VISIBILITY TO 5 MILES OR LESS IN
SPOTS.

THE WIND SHOULD CONTINUE TO FAVOR THE NORTHEAST AT 6 TO 12 KNOTS.
GUSTS NEAR 20 KNOTS ARE POSSIBLE FROM AROUND KPHL EAST AND SOUTHWARD
ON THURSDAY.

OUTLOOK...

THURSDAY NIGHT THROUGH SATURDAY: FREQUENT MVFR/IFR CEILINGS AND
VSBYS WITH SCATTERED SHOWERS. EASTERLY WINDS UP TO 10 KNOTS WITH
HIGHER GUSTS UP TO 20 KNOTS ON FRIDAY.

SATURDAY NIGHT THROUGH SUNDAY NIGHT: MAINLY VFR WITH SCATTERED
SHOWERS. SOUTHWEST WINDS INCREASING WITH GUSTS AROUND 20 KNOTS
SUNDAY AFTERNOON. WINDS SHIFTING TO NORTHWEST DURING THE DAY SUNDAY.

MONDAY: VFR, WEST TO NORTHWEST WINDS AROUND 10 KNOTS WITH HIGHER
GUSTS.

&&

.MARINE...
LOW PRESSURE ALONG AND OFF THE MIDDLE ATLANTIC COAST WILL MAINTAIN A
NORTHEASTERLY FLOW ON OUR COASTAL WATERS FOR TONIGHT AND THURSDAY.
WAVE HEIGHTS ON OUR OCEAN WATERS SHOULD BUILD TO 4 TO 7 FEET AND
GUSTS NEAR 25 KNOTS ARE POSSIBLE. THE SMALL CRAFT ADVISORY HAS BEEN
EXPANDED TO INCLUDE OUR WATERS OFF DELAWARE.

OUTLOOK...

AN SCA IS NOW IN EFFECT THROUGH FRIDAY AFTERNOON. SEAS WILL REMAIN
AT OR JUST OVER FIVE FEET THROUGH SATURDAY. SEAS WILL DECREASE FOR
THE EARLY PART OF NEXT WEEK. A PERIOD OF EASTERLY WIND GUSTS AROUND
20 KNOTS IS LIKELY FRIDAY ALONG WITH A PERIOD OF NORTHWESTERLY WIND
GUSTS AROUND 20 KNOTS ON SUNDAY.

&&

.TIDES/COASTAL FLOODING...
THE TIDAL SURGE RANGED FROM +0.7 TO +1.0 FOOT ALONG THE NEW JERSEY
AND DELAWARE COAST DURING THIS MORNING`S HIGH TIDE. THE PERSISTENT
NORTHEAST FLOW WILL LIKELY CAUSE THE TIDAL SURGE TO BE AROUND +1.0
TO +1.3 FEET FOR THIS EVENING`S HIGH TIDE. THOSE VALUES ALONG WITH
THE INCREASING ASTRONOMICAL TIDES AS WE APPROACH FRIDAY`S NEW MOON
SHOULD RESULT IN MINOR TIDAL FLOODING ALONG THE NEW JERSEY AND
DELAWARE COASTS THIS EVENING. THE COASTAL FLOOD ADVISORY REMAINS IN
EFFECT.

MINOR TIDAL FLOODING IS ALSO LIKELY TO EXTEND INTO THE HIGH TIDE
CYCLES THURSDAY AND FRIDAY NIGHT CYCLES.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...COASTAL FLOOD ADVISORY UNTIL 11 PM EDT THIS EVENING FOR
     NJZ012>014-020>027.
DE...COASTAL FLOOD ADVISORY UNTIL 11 PM EDT THIS EVENING FOR
     DEZ002>004.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EDT FRIDAY FOR ANZ450>455.

&&

$$
SYNOPSIS...GAINES
NEAR TERM...IOVINO
SHORT TERM...IOVINO
LONG TERM...GAINES
AVIATION...GAINES/IOVINO
MARINE...GAINES/IOVINO
TIDES/COASTAL FLOODING...


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