Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000
FXUS61 KPHI 221427
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1027 AM EDT FRI AUG 22 2014

.SYNOPSIS...
A HIGH CENTERED OVER EASTERN CANADA NOW, WILL SLOWLY BUILD SOUTH
APPROACHING THE REGION OVER THE WEEKEND. THIS WILL REMAIN THE
DOMINANT WEATHER FEATURE FOR OUR REGION THROUGH EARLY NEXT WEEK. A
COLD FRONT WILL APPROACH THE AREA LATE NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
1017AM UPDATE TO ADD SPRINKLES INTO THE LATE MORNING PORTION OF
THE FCST AWAY FROM THE COAST AND OTHERWISE DIMINISHED THE CHANCE
OF RAIN ALONG THE COAST TO NO MENTION.

PWAT 1.5 TO 1.75 INCHES WITH ML CAPE 500 TO 1000J SETS THE STAGE
FOR MORE GULLY WASHERS LATE THIS AFTN OR TONIGHT...PARTICULARLY IN
E PA AND OR W NJ AS PER THE 06Z NAM. SUCCESSIVE CYCLES OF THE NAM
AND THE 00Z/21 NSSL WRF AS WELL AS THE ECMWF TO SOME EXTENT WERE
THE BEST MODELS AT HIGHLIGHTING LAST NIGHTS TORRENTS THAT IN SOME
PLACES WERE EXCESSIVE ACROSS NE PA AND NW NJ. LSR`S AND PNS`S WILL
HIGHLIGHT THOSE AMTS.

THIS MORNING...WE`RE IN A LULL AS PER COSPA/HRRR AND INN THE
PROCESS OF LIFTING AND THINNING THE CIGS OF 500 TO 1500 FT.

THIS AFTERNOON...COOLER THAN YDY DUE TO COMBINED CLOUD AND EAST-
SOUTHEASTERLY FLOW. HOW MUCH DEVELOPS IN THE WAY OF SHOWERS IS
DEBATABLE BUT MAINTAINED CONTINUITY WITH OUR EARLIER FCST.

TONIGHT...UPSLOPE FLOW AND POSSIBLY A NW FLOW SHORT WAVE TRIGGER
MAY BE FAVORING A POCKET OR TWO OF EXCESSIVE RAIN IN E PA. JURY
STILL OUT ON THIS AND AM UNLIKELY TO HIT THIS HARD TONIGHT PER
THE 12Z/22 NAM DELAY AND FURTHER WEST...NOW AXISED FROM KILG-
KIPT. STILL SOMETHING SUBSTANTIAL IS LIKELY TO OCCUR IN A NARROW
SWATH OF E PA SOMETIME LATER TONIGHT OR SATURDAY.

&&

.SHORT TERM /SATURDAY/...
ALMOST SEEMS LIKE A BROKEN RECORD; THERE REMAINS THE CHANCE FOR
SHOWERS/THUNDERSHOWERS DURING THE DAY SATURDAY INTO SATURDAY
EVENING AS ANOTHER SHORT WAVE/VORTICITY MAX PUSHES ACROSS THE
AREA. ONCE THIS IMPULSE SLIDES ACROSS THE AREA SATURDAY EVENING,
SHOWER CHANCES DROP OFF OVERNIGHT SATURDAY INTO SUNDAY MORNING AS
HIGH PRESSURE WILL BEGIN PUSHING INTO THE AREA FROM THE NORTHEAST.

CONTINUED A BLEND OF MAV/MET MOS, MOSGUIDE, AND ECMWF 2M TEMPS FOR
HIGHS AND LOWS TONIGHT-SATURDAY NIGHT.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
THROUGH WEDNESDAY...THE HIGH WILL CONTINUE TO SETTLE IN OVER THE
REGION FROM THE NORTH. WEAK ON SHORE FLOW THROUGH AT LEAST MONDAY
WILL HELP TO KEEP HIGHS BETWEEN 5 AND 10 DEGREES BELOW NORMAL EACH
DAY. BY WEDNESDAY...THE HIGH WILL HAVE SHIFTED ENOUGH OFF SHORE TO
LEAVE THE REGION UNDER SOUTHERLY FLOW BRINGING TEMPERATURES ONCE
AGAIN NEAR NORMAL. BUT IT DOESN`T LOOK LIKE THE WARM WEATHER WILL
BE AROUND FOR VERY LONG.

THURSDAY THROUGH FRIDAY...MODELS HAVE SLOWED THE TIMING OF THE
NEXT COLD FRONT SLIGHTLY AS COMPARED TO PREVIOUS RUNS, WITH IT NOW
FORECAST TO ARRIVE LATE THURSDAY OR EARLY FRIDAY. THUS...THURSDAY
SHOULD ONCE AGAIN BE NEAR NORMAL. THE FRONT WILL BRING THE NEXT
PROMISING CHANCES FOR PRECIPITATION ACROSS THE REGION, AS WELL AS
TEMPERATURES WELL BELOW NORMAL FOR FRIDAY.

&&

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

TODAY...CIGS 700 TO 2000 FT AT 14Z WILL SLOWLY LIFT TO MAINLY
VFR CIGS THIS AFTN. SCATTERED SPRINKLES POSSIBLE THIS MORNING.
SCATTERED HEAVIER SHOWERS ARE AGAIN POSSIBLE LATER TODAY, SO THEY
WERE INCLUDED IN THE TAFS AS VCSH. THERE IS THE POTENTIAL FOR
THUNDERSTORMS, BUT CONFIDENCE IN OCCURRENCE AND TIMING WAS LOW, SO
THEY WERE KEPT OUT FOR NOW. WINDS TODAY WILL GENERALLY BE OUT OF
THE EAST SOUTHEAST 5-10 KNOTS WITH GUSTS TO 15 KT POSSIBLE.

TONIGHT...WE EXPECT MVFR CONDITIONS TO DEVELOP ONCE AGAIN LATER
THIS EVENING ACROSS THE TAF SITES AS MOISTURE POOLS AT THE LOW-
LEVEL INVERSION. IN FACT, CIGS MAY END UP LOWERING TO IFR FOR MANY
AREAS OVERNIGHT. CHANCE OF SHOWERS OR A TSTM...ESPECIALLY E PA TAF
SITES. WINDS WILL REMAIN EASTERLY 5-10 KNOTS.

SATURDAY...MVFR/IFR CIGS EARLY...BECOMING VFR CIGS DURING THE AFTERNOON.
SCATTERED SHOWERS POSSIBLE.

OUTLOOK...

SATURDAY NIGHT THROUGH TUESDAY...MOSTLY VFR.

&&

.MARINE...
SUB-SMALL CRAFT ADVISORY CONDITIONS EXPECTED TO CONTINUE THROUGH
TONIGHT. HOWEVER, SEAS MAY BEGIN TO APPROACH 4 FEET AND WINDS MAY
BEGIN TO GUST AROUND 20 KNOTS OVERNIGHT AS EARLY FLOW INCREASES AS
HIGH PRESSURE APPROACHES THE AREA FROM THE NORTH.

SATURDAY...CONDITIONS MAY APPROACH SMALL CRAFT ADVISORY LEVELS AS
EASTERLY FLOW INCREASES AS HIGH PRESSURE BUILDS IN FROM THE NORTH.


OUTLOOK...
SATURDAY NIGHT...CONDITIONS MAY APPROACH SMALL CRAFT ADVISORY
LEVELS AS EASTERLY FLOW INCREASES AS HIGH PRESSURE BUILDS IN FROM
THE NORTH.

SUNDAY THROUGH TUESDAY...WINDS AND SEAS SHOULD STAY BELOW
SMALL CRAFT ADVISORY CRITERIA THROUGH AT LEAST TUESDAY.

&&

.RIP CURRENTS...
RIGHT NOW LOW RISK TODAY SINCE THE GUSTY EAST WINDS OF VERY EARLY
THIS MORNING HAVE SUBSIDED.

THE RISK FOR THE FORMATION OF DANGEROUS RIP CURRENTS MAY INCREASE
TO MODERATE THIS WEEKEND ALONG THE NJ COAST WITH EASTERLY SWELL
OF 3 TO 4 FEET AT 7 SECONDS COMBINING WITH THE PERSISTENT ONSHORE
FLOW OF 15 KT TO BUILD THE WATER BEHIND THE SAND BARS.

&&

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

&&

$$
SYNOPSIS...JOHNSON
NEAR TERM...DRAG  1026
SHORT TERM...DRAG
LONG TERM...JOHNSON
AVIATION...DRAG/JOHNSON 1026
MARINE...DRAG/JOHNSON
RIP CURRENTS...






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