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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KPHI 070849
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
349 AM EST FRI MAR 7 2014

.SYNOPSIS...
A LOW PRESSURE SYSTEM ALONG THE SOUTHEASTERN SEABOARD WILL SLOWLY
MOVE NORTHEAST OFF THE CAROLINA COAST TODAY AND THEN RAPIDLY OUT TO
SEA LATE TONIGHT INTO EARLY SATURDAY. MEANWHILE, A COLD FRONT WILL
APPROACH FROM THE WEST AND CROSS OUR REGION LATE SATURDAY. HIGH
PRESSURE IS THEN EXPECTED TO BUILD TO OUR SOUTH INTO EARLY NEXT
WEEK. A WEAK DISTURBANCE OR FRONTAL BOUNDARY MAY PASS THROUGH THE
AREA AROUND TUESDAY, FOLLOWED BY THE POTENTIAL FOR A LOW PRESSURE
SYSTEM TO DEVELOP TO OUR SOUTH AND PASS OVER OUR REGION WEDNESDAY
INTO THURSDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HIGH PRESSURE WILL BE LOCATED TO THE NE TODAY.  AN AREA OF LOW
PRESSURE WILL MOVE FROM NEAR THE NC COAST NEWD WELL OUT TO SEA.  ITS
IMPACTS WILL BE MINIMAL ACRS THE REGION, BUT IT WILL BRING CLOUDS
AND SOME RAIN, MAINLY TO SOUTHERN AND EASTERN AREAS TODAY INTO THIS
EVENING.

DEPENDING ON HOW FAST THE PRECIP MOVES IN AND THE TEMPS, THERE COULD
BE SOME FREEZING DRIZZLE/RAIN OR EVEN SLEET AT THE ONSET.  HOWEVER,
TEMPS SHOULD WARM ENOUGH AFTER DAYBREAK FOR ANY PRECIP TO TURN OVER
TO PLAIN RAIN, BUT WILL CONTINUE TO MONITOR TRENDS.  CURRENT RADAR
SHOWED BULK OF PRECIP STILL WELL DOWN IN NC.

TEMPS ARE EXPECTED TO RISE TODAY TO THE MID 30S N AND W AND FROM
AROUND 40 TO THE LOWER 40S ELSEWHERE.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
THE AFOREMENTIONED LOW WILL CONTINUE ITS NEWD TREK TONIGHT.  ANY
IMPACTS SHOULD BE EARLY, WITH IMPROVEMENTS LATER ON TONIGHT AS HIGH
PRESSURE BUILDS IN FROM THE W.  OVERNIGHT LOW TEMPS SHOULD GENLY BE
IN THE 20S.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
A MAINLY QUIET START TO THE LONG TERM AS COASTAL LOW PRESSURE WILL
BE QUICKLY MOVING AWAY FROM THE CAROLINA COAST AND OUT INTO THE
ATLANTIC BY EARLY SATURDAY. THE LATEST MODEL GUIDANCE IS FAIRLY
CONSISTENT IN ENDING ANY LINGERING PRECIP ACROSS OUR FAR SOUTHEAST
ZONES PRIOR TO DAYBREAK SATURDAY. THE NEXT FEATURE TO WATCH THEN
WILL BE WEAK LOW PRESSURE SKIRTING ACROSS EASTERN CANADA AND ITS
ASSOCIATED COLD FRONT APPROACHING OUR REGION FROM THE WEST DURING
SATURDAY. AHEAD OF THIS BOUNDARY, AMPLE SUN IS EXPECTED THROUGH THE
BULK OF THE DAY, BEFORE CLOUDS INCREASE LATE. WINDS WILL BECOME MORE
WESTERLY THROUGH THE DAY, ALLOWING FOR SOME DOWNSLOPING INTO THE
REGION. OVERALL, THIS WILL MEAN A RATHER PLEASANT AND MILD DAY IS IN
STORE, WITH TEMPERATURES RIGHT AROUND AVERAGE FOR EARLY MARCH. WE
WENT SLIGHTLY ABOVE A MET/MAV BLEND FOR MAXIMUM TEMPERATURES AND
EXPECT HIGHS TO RANGE FROM THE LOWER 40S IN THE SOUTHERN POCONOS TO
THE LOWER 50S THROUGH SOUTHERN NJ AND THE DELMARVA.

BY SATURDAY NIGHT TO EARLY SUNDAY, THE PREVIOUSLY MENTIONED COLD
FRONT IS EXPECTED TO CROSS THE REGION. MODEL GUIDANCE OVER THE LAST
SEVERAL RUNS HAS BEEN CONSISTENT IN SHOWING LIMITED MOISTURE
ASSOCIATED WITH THIS FRONTAL PASSAGE, AND WE KEEP ONLY SLIGHT CHANCE
POPS FROM NORTHWEST TO SOUTHEAST THROUGH THIS TIMEFRAME WITH THE
FRONTAL PASSAGE FOR POSSIBLE LIGHT SNOW/RAIN SHOWERS. SOME CLEARING
IS EXPECTED THEN THROUGH THE DAYTIME SUNDAY, BUT A BRISK NORTHWEST
WIND WILL HELP TO FILTER IN NOTICEABLY COOLER AIR TO THE REGION,
WITH BELOW AVERAGE DAYTIME HIGHS RANGING MOSTLY FROM THE MID 30S
NORTH TO THE MID 40S SOUTH.

INTO EARLY NEXT WEEK, WEAK HIGH PRESSURE WILL BE BUILDING TO OUR
SOUTH WITH SOME SURFACE RIDGING INTO OUR AREA, ALLOWING FOR
CONTINUED QUIET WEATHER INTO MONDAY, WITH MODERATING TEMPERATURES.
WE GENERALLY TOOK A BLEND OF WPC GUIDANCE WITH CONTINUITY FOR MAX
TEMPERATURES AND FACTORED IN A LIGHT WEST-SOUTHWEST WIND, WITH ABOVE
AVERAGE HIGHS RANGING MOSTLY FROM THE MID 40S NORTH TO THE MID/UPPER
50S SOUTH. FROM HERE, THE WEAK SURFACE HIGH PUSHES FARTHER TO OUR
SOUTH, ALLOWING FOR A WEAK NORTHERN STREAM SYSTEM/FRONTAL BOUNDARY
TO PASS OVER THE REGION. TIMING OF ANY PRECIP ASSOCIATED WITH THIS
SYSTEM IS A LITTLE UNCERTAIN AT THIS TIME, BUT WE WILL CARRY SLIGHT
CHANCE POPS TUESDAY DAYTIME FOR OUR NORTHWEST ZONES LEADING TO LOW
CHANCE POPS FOR MUCH OF THE AREA INTO TUESDAY NIGHT.

OF EVEN LOWER CONFIDENCE AT THIS TIME IS THE POTENTIAL FOR A MORE
SIGNIFICANT LOW PRESSURE SYSTEM TO DEVELOP SOMEWHERE TO OUR
SOUTHWEST, PERHAPS OVER THE CENTRAL APPALACHIANS OR BACK ACROSS THE
TENNESSEE VALLEY DURING WEDNESDAY. WHILE MODEL SOLUTIONS DIFFER
GREATLY BETWEEN LOCATION, TRACK, AND STRENGTH OF THIS DEVELOPING LOW
PRESSURE, THERE IS A GENERAL CONSENSUS FOR THIS LOW TO THEN TRACK TO
THE COAST GOING INTO THURSDAY. DEPENDING ON ITS TRACK THEN EITHER
OUT TO SEA OR ALONG THE NORTHEAST COAST EARLY THURSDAY AND WITH A
POTENTIAL SHARPENING MID/UPPER TROUGH, MORE COLD AIR MAY BE BROUGHT
DOWN ACROSS THE REGION. FOR NOW, WE KEEP CHANCE POPS IN PLACE FOR
THE FCST AREA THROUGH THIS TIMEFRAME WITH THE POTENTIAL FOR
SNOW/RAIN DEPENDING ON THE TIMING AND TRACK OF LOW PRESSURE, AND WE
WILL REFINE THE DETAILS AS FUTURE MODEL RUNS SHOW BETTER AGREEMENT.

&&

.AVIATION /09Z FRIDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

CONDS RANGED FROM VFR TO MVFR THIS AM, AND A GENL DOWNWARD TREND IS
EXPECTED LATER THIS MRNG.  MOST LOCATIONS WILL BE MVFR TODAY INTO
TONIGHT WITH SRN AND ERN TAFS PSBLY IFR.  THIS IS DUE TO CLOUDS
ASSOCD WITH AN AREA OF LOW PRES NR THE NC CST.  THIS LOW WILL MOVE
BY WELL TO OUR E BUT THE LOW CLOUDS AND SOME RAIN WILL SKIRT THE
AREA THOUGH EARLY TONIGHT.  CONDS SHOULD IMPROVE LATER TONIGHT.

OUTLOOK...
SATURDAY...MAINLY VFR CONDITIONS.

SATURDAY NIGHT THROUGH SUNDAY...MAINLY VFR. BRIEF LIGHT RAIN/SNOW
SHOWERS POSSIBLE.

MONDAY AND TUESDAY...MAINLY VFR CONDITIONS.

&&

.MARINE...
HIGH PRES WILL BE LOCATED TO THE NE AND LOW PRES NR THE NC CST WILL
MOVE BY WELL OFF THE JERSEY SHORE BY SAT MRNG.  HIGH PRES WILL THEN
BUILD IN FROM THE W.  THE CURRENT SCA WILL REMAIN IN PLACE FOR BOTH
WIND AND SEAS THRU THE END OF THE SHORT TERM PD.

OUTLOOK...
SATURDAY...SMALL CRAFT ADVISORY CONDITIONS ARE EXPECTED TO CONTINUE
ON OUR COASTAL WATERS. WHILE WIND GUSTS WILL LIKELY BE BELOW SCA
LEVELS AS A STORM SYSTEM TRACKS FARTHER OUT TO SEA, ELEVATED SEAS
ARE FORECAST TO CONTINUE THROUGH THE DAYTIME SATURDAY, MOSTLY IN THE
5 TO 7 FOOT RANGE BEFORE SUBSIDING LATER SATURDAY NIGHT. MEANWHILE,
WINDS AND SEAS ARE EXPECTED TO BE SUB-SCA THROUGH DELAWARE BAY.

SUNDAY THROUGH TUESDAY...WINDS AND SEAS ARE EXPECTED TO BE BELOW SCA
LEVELS.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST SATURDAY FOR ANZ450>455.
     SMALL CRAFT ADVISORY UNTIL 6 AM EST SATURDAY FOR ANZ431.

&&

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