Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000
FXUS61 KPHI 051326
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
926 AM EDT SUN JUL 5 2015

.SYNOPSIS...
WEAK HIGH PRESSURE OVER THE MID ATLANTIC STATES MOVES OFFSHORE LATE
TODAY. A WARM FRONT IS EXPECTED TO LIFT THROUGH OUR REGION TUESDAY
MORNING. A WEAK COLD FRONT IS ANTICIPATED TO ARRIVE FROM THE
NORTHWEST ON WEDNESDAY. THIS FRONT WILL REMAIN IN OR NEAR OUR REGION
ON THURSDAY INTO FRIDAY WITH AN AREA OF LOW PRESSURE EXPECTED TO
MOVE ALONG THE FRONT AT THAT TIME. WEAK HIGH PRESSURE SHOULD FOLLOW
TO START NEXT WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FAIR WEATHER WILL PREVAIL TODAY WITH WEAK HIGH PRESSURE AT THE
SURFACE BUILDING ACROSS THE AREA THIS MORNING AND MOVING OFFSHORE
THIS AFTN. THIS WILL RESULT IN LIGHT SFC WINDS TODAY ALSO.  WITH
PLENTY OF SUNSHINE MAX TEMPS THIS AFTN SHOULD BE GENLY IN THE MID
80S...CLOSE TO NORMAL FOR THIS TIME OF YEAR. A GOOD SEA BREEZE IS
EXPECTED TO DEVELOP THIS AFTERNOON AND PUSH WELL INLAND BY EARLY
EVENING...WHICH WILL COOL THINGS OFF A BIT FOR AREAS CLOSER TO THE
SHORE.

LOW CLOUDS AND FOG HAVE PRETTY MUCH CLEARED OUT ALREADY, BUT THERE
COULD BE A FEW SPOTS WHERE THEY WILL REMAIN FOR ANOTHER HOUR OR
SO. OTHERWISE, NO SIG CHANGES TO THE FCST. BUMPED TEMPS UP A BIT
IN THE REAL NEAR TERM BASED ON CURRENT OBS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
LOW PRES ALOFT...OVER MIDDLE TN EARLY THIS MRNG...WILL MOVE
SLOWLY NEWD TOWARDS US TODAY AND TONIGHT. THIS WILL RESULT IN
INCREASING SLY FLOW OVER THE MID-ATLANTIC REGION WITH A GRADUAL
RETURN OF CLOUDS AND MOISTURE. THE MAIN EFFECT SHOULD BE MONDAY
AND BEYOND BUT HAVE KEPT A SLGT CHANCE FOR SHOWERS LATE TONIGHT
OVER DELMARVA. WINDS AT THE SFC WILL AGAIN BECOME RATHER LIGHT AND
CLOUDS SHOULD NOT BE TOO THICK OR WIDESPREAD...SO OVERNIGHT MIN
TEMPS SHOULD FALL INTO THE MID/UPPER 60S FOR MOST AREAS NORTH OF
DELMARVA.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
500 MB: THE WEAK MID LEVEL LOW OVER WEST VIRGINIA MONDAY MORNING
WEAKENS NORTHEASTWARD THROUGH THE MID ATLANTIC STATES TUESDAY.
THEN A SEASONABLE SUMMERTIME WESTERLY FLOW OCCURS WEDNESDAY THROUGH
NEXT WEEKEND, FRAUGHT WITH UNCERTAINTY REGARDING TIMING OF
SHOWERS/TSTMS.

TEMPERATURES: CALENDAR DAY AVERAGE TEMPERATURES WILL BE NEAR OR
SLIGHTLY ABOVE NORMAL MONDAY, THEN AROUND 5 DEGREES ABOVE NORMAL
TUESDAY AND WEDNESDAY WITH TEMPERATURES AT OR ABOVE NORMAL THURSDAY
THROUGH NEXT WEEKEND.

FORECAST BASIS: UNLESS OTHERWISE NOTED, A 50 50 BLEND 00Z/5 GFS/NAM
MOS GUIDANCE MONDAY-TUESDAY, 00Z/5 MEX MOS TUESDAY NIGHT AND
WEDNESDAY, THEN THE 0541Z/5 WPC GRIDDED ELEMENTS OF MAX/MIN TEMP,
12 HOUR POP, 6 HOUR DEWPOINT- SKY-WIND FROM WEDNESDAY NIGHT
THROUGH NEXT SATURDAY.

THE DAILIES BELOW...

MONDAY...WARM AIR ADVECTION INSTABILITY BURST SHOWER/TSTM THREAT
DEVELOPS FROM SSW TO NNE MONDAY AND MONDAY NIGHT, BEGINNING FIRST
OVER MD`S E SHORE AND SPREADING NORTHWARD, PRIMARILY INTO E PA MON
NIGHT. MONDAY DURING THE DAY FOR THE MOST PART SHOULD BE HALFWAY
DECENT. CONSIDERABLE MORNING MID AND HIGH CLOUD THINS OUT DURING
THE AFTERNOON. STRATUS AND/OR FOG APPEARS LIKELY LATE MONDAY NIGHT
AHEAD OF THE WARM FRONT (DENSE FOG ADVISORY?). WIND MAINLY S-SE
WITH MAX GUSTS 15 MPH. PWAT 1.5 INCHES AT PHL DAYBREAK MONDAY
INCREASES TO 1.85 MONDAY NIGHT. 1000JML CAPE DURING THE DAYLIGHT
HOURS MD E SHORE AND DE. CONFIDENCE: OVERALL AVERAGE THOUGH BELOW
AVERAGE REGARDING AREAL COVERAGE OF SHOWERS.

TUESDAY...PARTLY SUNNY, VERY WARM OR HOT, AND HUMID WITH A S-SW
WIND AND MAX GUSTS 20 MPH. SCT SHOWERS AND TSTMS WITH BRIEF
TORRENTIAL RAINS, MAINLY NE PA AND NNJ DURING THE DAY INTO THE
EARLY EVENING THEN THE RAIN THREAT DIMINISHES OR ENDS TUESDAY
NIGHT. 1000J MLCAPE, MAINLY NR I-95 KPHL NEWD.

PWAT NEAR 1.7 INCHES THROUGHOUT OUR FORECAST AREA. COOLING COASTAL
SOUTHERLY SEABREEZES DURING THE DAY ALONG THE IMMEDIATE COASTS
ONLY.

CONFIDENCE: AVERAGE ON TEMPS AND BELOW AVERAGE AREAL COVERAGE OF
TSTMS. ONE WOULD THINK THIS WARM SECTOR PATTERN SHOULD PRODUCE 90F
HEAT IN THE I-95 CORRIDOR AND ALSO SOME TORRENTIAL DOWNPOURS IN
TSTMS ASSOCIATED WITH THE LEFTOVER MID LVL COOL POOL PASSING
THROUGH. RIGHT NOW, K INDEX FCSTS SUGGEST THUNDER CHANCES ARE BEST
ALONG AND N OF I-78.


WEDNESDAY...HOT AND HUMID WITH A GOOD CHANCE OF AFTN TORRENTIAL RAIN
PRODUCING TSTMS ALONG A WEAK COLD FRONT.  BEST CHC APPEARS TO BE I-
78 NORTHWARD.  LESS THAN 1000J MLCAPE MAINLY I-78 NORTH.  PATCHY FOG
LATE WED NIGHT IN THE WEAK FRONTAL ZONE. SW WIND WITH MAX GUSTS 20
MPH TURN NW AT NIGHT. PWAT NEAR 1.8 INCHES TO START THE DAY.
CONFIDENCE: AVERAGE, IN PART BECAUSE THE ECMWF IS NOT AS HOT AS
I`D EXPECT WITH 17-18C AT 850MB.

THURSDAY...LOW CONFIDENCE FOR THIS DAY OF THE FCST. A CONTINUED
THREAT OF SHOWERS AND TSTMS SINCE THE FRONTAL BOUNDARY STALLS
ALONG THE MASON DIXON LINE ALONG WITH CONSIDERABLE CLOUDINESS?
SINE THE ECMWF STABILIZES FOR THE DAYLIGHT HOURS RESTRICTED THE
THUNDER TO THU NIGHT WHEN WAA SHOULD REDEVELOP NEAR WEAK LOW
PRESSURE.

STRATUS/FOG POSSIBLE LATE THU NIGHT ALONG WHAT MIGHT BE A WEAK
BACK DOOR COLD FRONT I-78 NORTH. CONFIDENCE: BELOW AVERAGE.

FRIDAY AND SATURDAY: FOLLOWED WPC GUIDANCE. LIGHT WIND.
CONFIDENCE BELOW AVERAGE.

&&

.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

VFR CONDS HAVE RETURNED MOST EVERYWHERE AND WILL CONTINUE THRU THE
TAF PD. SOME LCL MVFR STILL HOLDING AT RDG, BUT SHUD DISSIPATE IN
THE NEXT HOUR OR SO.

WINDS WILL BE LIGHT THIS MORNG AS WEAK SFC HIGH PRES MOVES ACROSS
THE AREA... BUT BECOMING SLY THIS AFT AS THE HIGH MOVES OFFSHORE
AND A SEA BREEZE PUSHES INLAND ACROSS NJ AND DE. VFR CONDS SHOULD
ALSO CONTINUE THROUGH TONIGHT WITH LIGHT WINDS.

OUTLOOK...
MONDAY...MAINLY VFR SCT-BKN AOA 5000 FT. S-SE WIND MAX GUSTS 15
KT. CHANCE OF SHOWERS OR EVEN A TSTM FROM KILG THROUGH
KPHL-KPNE-KRDG AND KABE. CONFIDENCE: AVERAGE

MONDAY NIGHT AND TUESDAY MORNING...CONDITIONS PROBABLY LOWERING TO
MVFR OR IFR IN LOW CLOUDS FOG BETWEEN 06Z-14Z/7.  LIGHT SOUTH WIND.
CONFIDENCE: ABOVE AVERAGE

TUESDAY AFTERNOON AND TUESDAY EVENING...MAINLY VFR WITH A CHANCE
OF SHOWERS AND THUNDERSTORMS. GRADIENT SW WIND GUST 15-20 KT
DURING THE AFTERNOON. CONFIDENCE: AVERAGE.

TUESDAY NIGHT AND WEDNESDAY MORNING...CONDITIONS POSSIBLY LOWERING
TO MVFR OR IFR IN LOW CLOUDS, HAZE AND FOG ESPECIALLY DURING THE
LATE NIGHT AND EARLY MORNING HOURS. LOOKS A LOWER CHANCE OF IFR
ST/FOG EARLY WEDNESDAY THAN THE PREVIOUS EARLY TUESDAY MORNING.
CONFIDENCE: AVERAGE

WEDNESDAY AFTERNOON THROUGH THURSDAY...SCATTERED SHOWERS AND
THUNDERSTORMS POSSIBLY CAUSING CONDITIONS TO LOWER TO MVFR OR IFR
AT TIMES. GRADIENT SW WIND PROBABLY GUSTS 15-20 KT DURING THE
AFTERNOON. CONFIDENCE:AVERAGE.

&&

.MARINE...
GENLY LIGHT WINDS AND SEAS SHOULD PREVAIL THROUGH TODAY AND TONIGHT.
SOMEWHAT STRONGER ONSHORE FLOW SHOULD DEVELOP THIS AFTERNOON ALONG
WITH SLY WINDS BLOWING UP DEL BAY. HIGH PRES MOVING OFFSHORE BY LATE
TODAY WILL HELP MAINTAIN A SLY TO SELY FLOW OVERNIGHT.

OUTLOOK...
MONDAY THROUGH THURSDAY...NO MARINE HEADLINES ARE ANTICIPATED.
THERE IS A SMALL CHANCE AN SCA MIGHT BE NEEDED FOR ATLANTIC SEAS
LATE TUESDAY BUT THE PROBABILITY AT THIS TIME IS
LOW.

&&

.RIP CURRENTS...
LOW RISK TODAY FOR THE FORMATION OF DANGEROUS RIP CURRENTS. LOW
DOES NOT MEAN NO RISK.

LOOKS TO BE SLIGHTLY LESS ROUGH OUT THERE THIS MORNING THAN
COMPARED TO YDY PER OUR LBI OBSERVER. THE LEFTOVER SWELL FROM
YDYS LITTLE SEAWARD MOVING VIRGINIA CAPES LOW PRESSURE SYSTEM
SHOULD SETTLE SLIGHTLY LATE THIS MORNING AND AFTERNOON. THE TIDE
WILL BE GOING OUT THIS AFTERNOON WHICH TENDS TO BE THE MORE
DANGEROUS TIME FOR FORMING RIP CURRENTS.

ENJOY THE BEACHES AND SWIM UNDER THE WATCHFUL SAFETY NET OF THE
VIGILANT AND RESPONSIVE LIFE GUARD CREWS UP AND DOWN OUR COASTS.

SWIMMING ALONE OR NEAR JETTIES AND PIERS IS LESS SAFE AND NOT A
BEST PRACTICE.

&&

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

&&

$$
SYNOPSIS...DRAG
NEAR TERM...AMC/NIERENBERG
SHORT TERM...AMC
LONG TERM...DRAG
AVIATION...AMC/DRAG
MARINE...AMC/DRAG
RIP CURRENTS...



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