Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000
FXUS61 KPHI 270137
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
937 PM EDT FRI SEP 26 2014

.SYNOPSIS...
HIGH PRESSURE WILL REMAIN OVER THE REGION THROUGH THE WEEKEND. A COLD
FRONT IS EXPECTED TO MOVE ACROSS THE AREA MONDAY, THEN PUSH TO OUR
SOUTH BY TUESDAY MORNING. A LOW PRESSURE SYSTEM MAY MOVE OFF THE
SOUTHEAST COAST EARLY NEXT WEEK AND THEN MOVE NORTHWARD AND MAY
IMPACT OUR REGION TUESDAY OR WEDNESDAY.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
THE MID-ATLANTIC REGION IS POSITIONED AROUND THE EASTERN PERIPHERY
OF A 1026 MB SFC HIGH CENTERED OVER THE GREAT LAKES. ONCE THE SUN
WENT DOWN, NORTHERLY WINDS DIMINISHED AND TEMPERATURES DROPPED
QUICKLY (ABOUT 10-15 DEGREES IN 2 HOURS). ADJUSTED MIN TEMPS DOWN A
FEW DEGREES FROM PREVIOUS FORECAST AS RADIATIONAL COOLING WILL
CONTINUE TO BE EFFECTIVE UNDER CLEAR SKIES AND CALM WINDS THRU THE
REMAINDER OF TONIGHT. THE AIRMASS IS DRY SO FOG SHOULD BE CONFINED
TO THE SHELTERED RIVER VALLEYS (WHERE WATER TEMPS ARE STILL
RELATIVELY WARM THIS TIME OF YEAR COMPARED TO THE AIR).

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/...
ANOTHER BEAUTIFUL DAY IS EXPECTED AS HIGH PRESSURE CONTINUES TO
OVERSPREAD THE MID ATLANTIC REGION. BOTH MOS GUIDANCE AND 850/925 MB
MODEL TEMPS INDICATE SATURDAY TO BE A FEW DEGREES WARMER ACROSS THE
REGION. SKIES ARE EXPECTED TO REMAIN MOSTLY CLEAR THROUGH THE DAY,
WITH LIGHT BREEZES MAINLY IN THE 5 TO 10 MPH RANGE. WE BLENDED THE
MET/MAV GUIDANCE WITH CONTINUITY FOR MAX TEMPERATURES AND EXPECT
HIGHS TO RANGE FROM THE MID/UPPER 70S ALONG THE COAST AND IN THE
POCONOS TO THE LOWER 80S ELSEWHERE.

&&

.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
THE EXTENDD PD STARTS OF QUIET, THEN THERE IS ANOTHER POTENTIAL
SHOT OF RAIN FOLLOWED LIKELY BY MORE QUIET.

A LARGE AREA OF HIGH PRESSURE WILL BE OVER THE REGION SAT NIGHT
THRU SUN NIGHT BEFORE MOVG OFFSHORE. THIS HIGH WILL KEEP BOTH
WEEKEND DAYS DRY AND VERY PLEASANT FOR LATE SEPTEMBER, WITH TEMPS
AVERAGING 5 TO 10 DEGREES ABOVE NRML.

A WK CDFNT WILL CROSS THE REGION ON MONDAY AS A LARGE HIGH BUILDS
TO THE N OVER ERN CANADA. AS IT DOES, THE MDLS BEGIN TO DIVERGE ON
WHAT HAPPENS AFTER MON, AND CONFIDENCE IS QUITE LOW.

EVERY PIECE OF AVAILABLE GUIDANCE ANOTHER CSTL LOW OFF THE
CAROLINA CST LATER MON INTO TUE. HOWEVER, THE GFS AND CMC KEEP
THIS LOW WELL ENOUGH OFF THE CST FOR LITTLE IF ANY IMPACT TO OUR
REGION. THE CMC IS VIRTUALLY DRY, AND THE GFS KEEPS SOME PRECIP
CONFINED TO THE CST MAINLY MON NIGHT INTO TUE THEN MOVES IT FAIRLY
QUICKLY AWAY WITH HIGH PRES BUILDING IN FOR THE REST OF THE WEEK.

ON THE OTHER HAND, THE ECMWF IS FURTHER W, SLOWER AND BRINGS MORE
IMPACT TO OUR REGION IN THE PD MON NIGHT THRU WED. IT ALSO KEEPS
THE LOW SPINNING OFF THE CST FOR A GOOD PORTION OF THE WEEK,
THOUGH HIGH PRES WILL BUILD IN. THE ECMWF IS ALONE IN ITS SOLN,
BUT CERTAINLY CAN NOT BE RULED OUT, ESPECIALLY SINCE IT WAS FIRST
TO THE GAME WITH THIS WEEK`S CSTL LOW. THE UKMET IS STRONGER AND
MORE CLOSED OFF THAN THE GFS/CMC BUT FASTER AND FURTHER E. SO
AGAIN, WOULD LIKE TO SEE MORE MDL AGREEMENT AND THIS REMAINS A LOW
CONFIDENCE FCST.

FOR NOW, WILL MAINTAIN LOW POPS THRU THE PD, BUT TIMING AND POSN
WILL HAVE TO BE ADJUSTED. ULTIMATELY LATER IN THE WEEK MAY NEED TO
BE ADJUSTED AS WELL, BUT WILL MAINTAIN A DRY FCST FOR NOW AS THERE
IS AMPLE TIME FOR CHANGES AND THE HOPE IS THE MDLS WILL COME INTO
BETTER AGREEMENT.

TEMPS WILL START OUT ABV NRML, BEFORE RETURNING TO NR NRML BY THE
END OF THE PD.

&&

.AVIATION /01Z SATURDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

VFR THIS EVE AT ALL TERMINALS. RADIATIONAL FOG MAY DEVELOP AT THE
THE USUAL TERMINAL (RDG, ABE, MIV) DURING THE EARLY MORNING
SATURDAY.

VFR CONDITIONS AND CONTINUED MAINLY CLEAR SKIES ON SATURDAY. ANY
PATCHY EARLY MORNING FOG SHOULD DISSIPATE RATHER QUICKLY BY ABOUT
12Z OR 13Z. LIGHT AND VARIABLE WINDS EARLY ARE EXPECTED TO
INCREASE INTO THE 5 TO 8 KNOT RANGE, MAINLY OUT OF THE NORTH-
NORTHEAST.

OUTLOOK...
SAT NIGHT-MON...VFR EXPECTED EXCEPT POSSIBLE PATCHY FOG AT NIGHT
AND EARLY MORNING HOURS WITH HIGH PRESSURE IN CONTROL.  HIGH CONFIDENCE

MON NIGHT-WED ...MVFR/IFR CIGS/VSBYS, RAIN, AND GUSTY WINDS
POSSIBLE, ESPECIALLY FOR COASTAL SITES, AS POSSIBLE COASTAL LOW
PASSES BY. BEST CHCS FOR REDUCED CIGS/VSBYS WOULD BE ON TUE. LOW
CONFIDENCE.

&&

.MARINE...
WINDS HAVE DIMINISHED EVEN FURTHER AND ARE BELOW 5 KT OVER THE
WATERS. WAVE HEIGHTS AT BUOY AT 44025 AND 44065 WERE 5 FT AT 9 PM
AND 6 FT OFF THE DE COAST AT 44009. WITH WINDS NOT BEING A FACTOR AT
ALL, SCA WAS REPLACED BY A SCA FOR HAZARDOUS SEAS THRU SATURDAY.

FOR DELAWARE BAY, WINDS AND SEAS WILL REMAIN BELOW SCA CRITERIA
THROUGH TONIGHT AND SATURDAY.

OUTLOOK...
SAT NIGHT-MON NIGHT...SUB-ADVISORY CONDITIONS EXPECTED OVER THE WEEKEND
INTO MONDAY.

TUE-WED...WINDS AND SEAS MAY INCREASE AHEAD OF A POSSIBLE
APPROACHING COASTAL LOW PRESSURE SYSTEM. MARINE FLAGS MAY BE
NEEDED FOR AT LEAST A PART OF THE AREA DURG A POTION OF THIS TIME,
BUT CONFIDENCE REMAINS LOW ON HOW THIS ALL DEVELOPS ATTM.

&&

.RIP CURRENTS...
MODERATE RIP CURRENT THREAT THIS EVENING. THE RIP CURRENT RISK
ARE FORECAST TO BE LOW ON SATURDAY AS SEAS DIMINISH AND WINDS
WILL BE LIGHT.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 8 PM EDT
     SATURDAY FOR ANZ450>455.

&&

$$
SYNOPSIS...NIERENBERG
NEAR TERM...KLEIN
SHORT TERM...KLINE
LONG TERM...NIERENBERG
AVIATION...KLEIN/NIERENBERG
MARINE...KLEIN/NIERENBERG
RIP CURRENTS...KLEIN





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