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000
FXUS61 KPHI 081159
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
659 AM EST SAT MAR 8 2014

.SYNOPSIS...
WEAK HIGH PRESSURE WILL BUILD INTO THE REGION TODAY. A COLD FRONT
WILL THEN CROSS THE AREA TONIGHT INTO SUNDAY MORNING. A LARGE AREA
OF HIGH PRESSURE WILL THEN BUILD IN BEHIND THE FRONT FOR THE FIRST
PART OF NEXT WEEK. A WEAK COLD FRONT WILL CROSS THE AREA MONDAY
NIGHT AS THE HIGH MOVES SOUTHWARD. THEN, AN AREA OF LOW PRESSURE,
DEVELOPING OVER THE GULF OF MEXICO, WILL MOVE NORTHEASTWARD AND
WILL BEGIN TO IMPACT THE REGION WEDNESDAY INTO EARLY THURSDAY.
HIGH PRESSURE WILL BUILD BACK IN BEHIND THE DEPARTING LOW.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A RATHER PLEASANT EARLY MARCH DAY IS IN STORE ACROSS THE REGION.
AMPLE SUNSHINE IS EXPECTED FOR THE FORECAST AREA, ESPECIALLY THROUGH
THE FIRST HALF OF THE DAY, BEFORE A COLD FRONT BEGINS TO APPROACH
THE REGION FROM THE NORTHWEST DURING THE MID TO LATE AFTERNOON.
CLOUDS WILL BE ON THE INCREASE AHEAD OF THIS BOUNDARY DURING THE
AFTERNOON HOURS, FROM NORTHWEST TO SOUTHEAST. THERE LOOKS TO BE
LIMITED MOISTURE ASSOCIATED WITH THIS BOUNDARY AS IT APPROACHES OUR
NORTHWEST ZONES LATE IN THE DAY, BUT WE HAVE KEPT SLIGHT CHANCE POPS
FOR LIGHT RAIN/SNOW SHOWERS MAINLY ACROSS THE SOUTHERN POCONOS FOR
THE LATE AFTERNOON TO EARLY EVENING.

WITH RESPECT TO TEMPERATURES, A NEAR AVERAGE DAY IS ANTICIPATED, AND
WE MAINLY TOOK A MET/MAV BLEND WITH A FEW LOCAL ADJUSTMENTS. HIGH
TEMPERATURES ARE EXPECTED TO RANGE FROM AROUND 40 DEGREES IN THE
SOUTHERN POCONOS TO THE LOWER AND PERHAPS MID 50S INTO THE SOUTHERN
DELMARVA. WINDS ARE EXPECTED TO REMAIN ON THE LIGHTER SIDE FOR MOST
OF THE REGION, GENERALLY OUT OF THE NORTHWEST EARLY AND BECOMING
WEST-NORTHWEST INTO THE AFTERNOON.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/...
GOING THROUGH THE EVENING TO OVERNIGHT, THE PREVIOUSLY MENTIONED
COLD FRONT WILL GRADUALLY TRAVERSE THE AREA FROM NORTHWEST TO
SOUTHEAST, CLEARING OUR REGION BEFORE DAYBREAK SUNDAY. WHILE
MOISTURE OVERALL CONTINUES TO BE LIMITED WITH THIS BOUNDARY AS IT
PASSES OVER THE REGION, MODEL GUIDANCE HAS BEEN CONSISTENT IN
SQUEEZING OUT A FEW RAIN/SNOW SHOWERS AS IT SAGS SOUTHEAST THROUGH
THE AREA. AS THE PRECIP WILL BE LIGHT AND AREAL COVERAGE SCATTERED
AT BEST, WE CARRY MOSTLY SLIGHT CHANCE POPS. LESS THAN A TENTH OF AN
INCH QPF IS EXPECTED, WITH MOST AREAS SEEING A FEW HUNDREDTHS OF AN
INCH AT BEST. SOME FCST SOUNDING DATA INDICATES THE POSSIBILITY FOR
FREEZING DRIZZLE, AND THIS IS INCLUDED FOR OUR NORTHWEST AREAS INTO
THE SOUTHERN POCONOS, LEHIGH VALLEY REGION, AND NORTHWEST NJ.

OVERNIGHT TEMPERATURES WERE MOSTLY A MET/MAV BLEND WITH CONTINUITY,
AND WE EXPECT MINIMUM TEMPS TO RANGE FROM THE LOWER/MID 20S FAR
NORTH TO THE MIDDLE 30S IN THE DELMARVA.

ALSO...DAYLIGHT SAVING TIME BEGINS SUNDAY MORNING AT 2 AM, SO
PLEASE REMEMBER TO TURN YOUR CLOCKS AHEAD ONE HOUR (SPRING AHEAD)
BEFORE GOING TO BED.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
THE EXTENDD PD IS FAIRLY QUIET, WITH TEMPS GENLY NEAR OR ABV NRML
(SOMETHING THAT I HAVEN`T BEEN ABLE TO SAY FOR QUITE SOME TIME!),
WITH THE EXCEPTION OF THE WED-THU TIME FRAME.

ON SUN, HIGH PRES WILL BE BUILD IN FROM THE W, BEHIND THE PASSAGE
OF A CDFNT. SUN LOOKS TO BE DRY. MON SHOULD BE DRY AS WELL, BUT A
WK CDFNT/CLIPPER TYPE SYS WILL APPROACH FROM THE NW. A FEW SNOW OR
RAIN SHOWERS CAN NOT BE RULED OUT N AND W WITH THE WK FRONT.

BY TUE, W TO SW FLOW ALOFT PICKS UP IN ADVANCE OF A DEVELOPING LOW
IN THE GLFMEX. TUE LOOKS TO BE THE WARMEST DAY OF THE PD. THIS LOW
THEN MOVES NEWD TUE NIGH AND BEGINS TO IMPACT THE REGION LATE TUE
NIGHT OR WED MRNG.

ALL OF THE GUID HAS WEAKENED THE LOW WITH TH 08/00Z CYCLE.
HOWEVER, IT STILL REMAINS STRONGEST IN THE ECMWF.  THE ECMWF
REMAINS THE SLOWEST OF THE GUID (THAT IS ABOUT AS SURPRISING AS
THE SUN RISING IN THE EAST!). THE GREATEST IMPACTS, BASED ON
CURRENT TIMING LOOK TO BE DURG THE DAY WED. THE GFS IS FASTEST,
BASICALLY ENDING ALL PRECIP BY WED EVE. THE CMC HAS PRECIP OVER BY
THU MRNG. THE ECMWF IS WINDING THINGS DOWN DURG THU AM, BUT IS
PROBABLY NOT DONE UNTIL THU LATE MRNG OR AFTN. THE ECMWF IS QUITE
A BIT STRONGER WITH THE LOW AFTER IT PASSES US (AS IT HAS BEEN ALL
ALONG) THAN THE OTHER MDLS AS WELL. SO THERE IS STILL QUITE A BIT
OF UNCERTAINTY WRT TIMING AND ULTIMATELY THE TRACK OF THE LOW.

FOR NOW, WILL GO WITH A BLEND, WILL REMOVE POPS FROM TUE NIGHT
THEN RAMP THINGS UP ON WED AND THEN DOWN DURG THU. ALSO, ATTM,
THIS LOOKS TO BE PREDOMINANTLY A RAIN EVENT ON WED, BUT WILL
LIKELY MIX AND CHANGE TO SNOW BEFORE ENDING FROM NW TO SE WED
NIGHT INTO THU. AS USUAL, IT WILL BE THE QUESTION OF HOW MUCH
MOISTURE WILL BE LEFT BY THE TIME THE COLDER AIR MOVES IN. THE
MDLS STILL HAVE ABOUT 5 DAYS TO WORK THESE DETAILS OUT AND WILL
CONTINUE TO JUST HOLD ONTO SOME FORM OF RAIN AND SNOW IN THE
GRIDS. HIGH PRESSURE WILL THEN BUILD IN BEHIND THE DEPARTING LOW
FOR THU NIGHT INTO FRI.

HIGH TEMPS SHUD STEADILY RISE THRU TUE, BEFORE DECREASING BUT
SHOULD GENLY BE IN THE 40S AND 50S FOR MOST LOCATIONS THRU THE
EXTENDD PD. THE COLDER NRN AND WRN AREAS WILL LIKELY ONLY SEE 30S
ON THU AND FRI. OVERNIGHT LOWS WILL MAINLY BE IN THE 20S AND 30S.
WITH SOME TEENS N AND W.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

TODAY...OVERALL, MAINLY VFR CONDITIONS. CLOUDS HAVE BEEN STEADILY
ERODING AWAY FROM WEST TO EAST ACROSS THE AREA THIS MORNING. KACY AND
KMIV ARE THE ONLY SITES STILL HOLDING ONTO MVFR CIGS, BUT WE
EXPECT IMPROVEMENT TO VFR BY AROUND 13Z. MAINLY LIGHT AND
VARIABLE WINDS ARE EXPECTED AT KRDG/KABE THROUGH EARLY TODAY.
ELSEWHERE, A NORTHWEST WIND AT 10KT OR LESS WILL PREVAIL EARLY, BECOMING
MORE WEST- NORTHWEST WITH SOME POSSIBLE GUSTS IN THE 15 TO 18KT
RANGE FOR THIS AFTERNOON FROM AROUND KPHL SOUTH AND EAST.

TONIGHT...MAINLY VFR CONDITIONS ARE EXPECTED TO CONTINUE. A COLD
FRONT WILL BE MOVING THROUGH THE AREA FROM NORTHWEST TO SOUTHEAST
DURING THE LATE EVENING TO OVERNIGHT. WHILE LIMITED MOISTURE IS
ASSOCIATED WITH THIS BOUNDARY, WE CANNOT RULE OUT A FEW LIGHT
RAIN/SNOW SHOWERS ALONG AND BEHIND THE FRONTAL BOUNDARY. THIS COULD
LEAD TO SOME BRIEF PERIODS OF SUB-VFR CONDITIONS, BUT CONFIDENCE ON
TIMING AND LOCATION IS BELOW AVERAGE AT THIS TIME. WINDS ARE
EXPECTED TO BE WEST-NORTHWEST AT 10 KT OR LESS DURING THE EVENING,
BECOMING MORE NORTHWEST FOLLOWING THE FRONTAL PASSAGE.

OUTLOOK...
SUN...MAINLY VFR. THERE COULD BE SOME LINGERING LOW CLOUDS EARLY
AND PSBL LWR CIGS, BUT THESE SHOULD DISSIPATE AS HIGH PRES BUILDS
IN. MDT TO HIGH CONFIDENCE.

MON-TUE...VFR. HIGH PRESSURE. HIGH CONFIDENCE.

TUE NIGHT-WED...MVFR OR LOWER IN SCATTERED SHOWERS. INCREASING CHANCES
FOR MORE RAIN/SNOW DURG WED AS LOW PRESSURE APPROACHES FROM THE
SW. LOW TO MDT CONFIDENCE ON TIMING. HIGHER CONFIDENCE ON IMPACTS
WHEN THEY OCCUR.

&&

.MARINE...
IN THE WAKE OF A COASTAL LOW PRESSURE TO OUR SOUTHEAST THAT IS NOW
QUICKLY MOVING OUT TO SEA, ELEVATED SEAS WILL CONTINUE FOR OUR
COASTAL WATERS. WE CONTINUE WITH OUR CURRENT SMALL CRAFT ADVISORY
FOR ALL OF OUR COASTAL WATERS INTO THIS EVENING, AND WE WILL
CONTINUE TO MONITOR SEAS TO DETERMINE IF THIS SCA NEEDS TO BE
EXTENDED INTO TONIGHT. AT THIS TIME, SEAS IN THE 5 TO 9 FOOT RANGE
WILL CONTINUE FOR OUR COASTAL WATERS, HIGHEST FOR OUR SOUTHERN
WATERS. IN FACT, SEAS AT BUOY 44009 ARE STILL CLOSE TO 10 FEET. A
GRADUAL DOWNWARD TREND FOR SEAS IS EXPECTED THROUGH THE DAY. SOME
MARGINAL SCA WIND GUSTS AROUND 25 KTS ARE ALSO POSSIBLE EARLY,
ESPECIALLY OUT 20NM, BUT WIND GUSTS WILL ALSO BE SLOWLY LOWERING
THROUGH THE DAY.

ELSEWHERE, WINDS HAVE DIMINISHED THROUGH LOWER DELAWARE BAY THIS
MORNING, AND THUS THE SMALL CRAFT ADVISORY WAS ALLOWED TO EXPIRE
THERE. WINDS TODAY THROUGH DELAWARE BAY WILL PRIMARILY BE BETWEEN
10 TO 15 KNOTS, WITH SEAS MAINLY 1 TO 3 FEET.

OUTLOOK...
SUN-TUE...SUB-SCA CONDS ARE EXPECTED.

TUE NIGHT-WED...WIND AND OR SEAS MAY INCREASE IN ADVANCE OF
APPROACHING LOW PRES AND PSBL CSTL LOW. SCA FLAGS MAY BE NEEDED
DURG THE PD, BUT CONFIDENCE IS LOW ATTM.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR
     ANZ450>455.

&&

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