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000
FXUS61 KPHI 042032
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
332 PM EST WED DEC 4 2013

.SYNOPSIS...
HIGH PRESSURE OFF THE EAST COAST WILL MOVE FURTHER OFFSHORE TONIGHT
AND THURSDAY. A COLD FRONT WILL CROSS THE REGION THURSDAY NIGHT AND
FRIDAY, WITH ANOTHER AREA OF HIGH PRESSURE BUILDING IN FROM THE
NORTHWEST SATURDAY INTO SUNDAY. A WARM FRONT IS EXPECTED TO LIFT
NORTH SUNDAY NIGHT INTO MONDAY MORNING, FOLLOWED BY ANOTHER COLD
FRONT LATE MONDAY. HIGH PRESSURE WILL THEN BUILD IN FROM THE WEST
THROUGH THE MID PART OF NEXT WEEK.
&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
A STRONG AREA OF LOW PRESSURE WILL MOVE NORTHWARD THROUGH THE GREAT
LAKES REGION AND INTO CANADA TONIGHT. AN ASSOCIATED WEAK WARM FRONT
WILL MOVE NORTHWARD INTO OUR AREA OVERNIGHT ALONG WITH A WEAK
MID-LEVEL SHORTWAVE. WITH PLENTY OF LOW-LEVEL MOISTURE AROUND THE
REGION, THERE MAY BE SOME LIGHT RAIN OR DRIZZLE THAT DEVELOPS AND
MOVES THROUGH THE REGION OVERNIGHT TOWARD THURSDAY MORNING.

THERE WILL CONTINUE TO BE WARMING THROUGH THE LOW AND MID LEVELS OF
THE ATMOSPHERE AND IN TURN, TEMPERATURES WILL REMAIN QUITE MILD.
WITH PRETTY GOOD CLOUD COVER OVERNIGHT, WE WILL NOT BE RADIATING ALL
THAT WELL, WHICH WILL ALSO KEEP US ON THE WARMER SIDE.

IN ADDITION, AS THE WARM FRONT MOVES THROUGH, MORE WARM AIR WILL BE
PUSHED INTO THE AREA. THIS WILL ALLOW FOR RISING TEMPERATURES
OVERNIGHT, WITH THE LOWS OCCURRING BEFORE MIDNIGHT IN MOST
LOCATIONS. EXPECT LOW TEMPERATURES TO BE IN THE 40S ACROSS THE
REGION.
&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/...
THE AFOREMENTIONED WARM FRONT WILL PUSH NORTH OF THE REGION BY
LATE MORNING. LIGHT WINDS WILL START TO PICK UP JUST A BIT FROM
THE SOUTH SOUTHWEST. PRECIPITATION WILL CONTINUE MAINLY ACROSS THE
NORTHERN HALF OF THE CWA, SPREADING TO THE SOUTH TOWARD THE
EVENING AS A COLD FRONT APPROACHES FROM THE WEST.

WARM AIR WILL CONTINUE TO REMAIN OVER THE REGION IN THE SOUTHWEST
FLOW WITH UNSEASONABLY HIGH TEMPERATURES FORECAST. WE ARE NOT
EXPECTING ANY RECORDS TO OCCUR AS THE RECORDS ARE ANOMALOUSLY HIGH
FOR THIS DATE IN DECEMBER. REGARDLESS, EXPECT HIGH TEMPERATURES TO
REACH WELL INTO THE UPPER 50S TO MID 60S ACROSS THE REGION.
&&

.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
THE MID-TO-UPPER LEVEL PATTERN DURING THE EXTENDED PORTION OF THE
FORECAST PERIOD FLUCTUATES BETWEEN RIDGING IN THE EAST TO A MORE
ZONAL PATTERN, THEN BACK TO RIDGING, THEN BACK TO ZONAL, AND THE
TEMPERATURE PATTERN WILL MIMIC THIS PATTERN (WARMER THAN NORMAL,
SLIGHTLY BELOW NORMAL, WARMER THAN NORMAL, BELOW NORMAL).  GIVEN
THIS PATTERN, THE STORM TRACK WON`T STRAY FAR FROM THE MID-ATLANTIC
REGION, SO AS PRECIPITATION MOVES THROUGH FROM TIME TO TIME, SOME OF
IT WILL FALL IN THE FROZEN FORM, ESPECIALLY NORTH OF THE I-95
CORRIDOR. AS ALWAYS, THE DEVIL IS IN THE DETAILS, AND THIS FAR OUT,
THOSE DETAILS ARE SUBJECT TO CHANGE AS TIME MOVES CLOSER TO THE
ACTUAL EVENTS. HOWEVER, THE 12Z GFS IS FAIRLY SIMILAR TO ITS EARLIER
RUN, SO AT LEAST FOR NOW THERE IS SOME CONSISTENCY TO GRAB ON TO. THE
BREAKDOWN IS AS FOLLOWS:

THU NIGHT THRU FRI NIGHT...WET. THE COLD FRONT ASSD WITH A DEEP LOW
MOVING THROUGH CENTRAL AND EASTERN CANADA WILL CROSS THE AREA FRI MORNING.
A WEAK AREA OF LOW PRESSURE WILL MOVE ALONG IT FRI NIGHT/EARLY SAT
ONLY ADDING TO PCPN CHANCES. TEMPERATURES WILL BE MILD THU
NIGHT...BUT THEN BEGIN DROPPING BEHIND THE FRONT FRI. LOWS WILL FALL
BACK BELOW FREEZING BY SAT MORNING OVER MUCH OF THE NRN/WRN AREAS.
PCPN WILL PROBABLY END AS SNOW ACROSS THE FAR NRN/WRN AREAS. A LIGHT
ACCUM OF SNOW IS POSSIBLE BY SAT MORNING ACROSS THE HIGHER
ELEVATIONS...ESPECIALLY IN THE FAR NORTH. AMOUNTS ARE EXPECTED TO BE
WELL BELOW ADVISORY CRITERIA.

SAT THRU SUN MORNING... A SHORT BREAK IN THE WET WEATHER AS HIGH
PRESSURE NOSES INTO THE AREA. COLD. HIGHS BACK A FEW DEGREES BELOW
NORMAL SAT AND 3-5 DEGREES COLDER ON SUN. HIGHS ACROSS THE SRN
AREAS MOSTLY IN THE LOW/MID 40S SAT AND CLOSE TO 40 ON SUN. READINGS
5-7 DEGREES COLDER ACROSS THE NRN AREAS.

SUN AFTERNOON THRU TUE MORNING...A WARM FRONT LIFTS NORTH WITH MORE
PCPN OVERSPREADING THE AREA ON SUN. TEMPERATURES INITIALLY COLD ENOUGH
FOR FROZEN/FREEZING PCPN. ONCE AGAIN SOME CHC FOR ACCUMS ACROSS THE
WRN/NRN AREAS. TEMPERATURES SHOULD THEN WARM OVERNIGHT AND ALL PCPN
CHANGES BACK TO RAIN BY MONDAY. QPF 0.2 TO 0.5 POSSIBLE.

TUE AFTERNOON/NIGHT...IMPROVING CONDITIONS...COLD. LOWS MOSTLY ON
THE 20S WITH TEENS FAR NORTH AND LOW 30S PHL METRO.

WED...CONTINUED COLD AS HIGH PRESSURE BUILDS IN FROM THE WEST.
&&

.AVIATION /21Z WEDNESDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

MVFR TO VFR CONDITIONS TO START THE TAF PERIOD WITH DETERIORATING
CONDITIONS LATER THIS AFTERNOON/EVENING AND CONTINUING THROUGH THE
REST OF THE TAF PERIOD.

HAZE CONTINUES TO REMAIN ACROSS THE REGION THIS AFTERNOON, REDUCING
VISIBILITIES TO 4 TO 6 SM. VISIBILITIES MAY INCREASE TO P6SM AT
TIMES THROUGH THIS AFTERNOON BUT WILL LOWER AGAIN THIS EVENING AND
OVERNIGHT. LOWEST VISIBILITIES ARE EXPECTED TO OCCUR ON THURSDAY
MORNING, DROPPING DOWN TO 2SM OR LOWER FOR A PERIOD OF TIME.

WINDS ARE LIGHT ACROSS THE REGION AND WILL CONTINUE TO REMAIN LIGHT
THROUGH THIS EVENING AND OVERNIGHT. BASES AROUND 3000-4000 FEET WILL
START TO LOWER THIS AFTERNOON TO MVFR LEVELS AND THEN CONTINUE TO
LOWER THROUGH THE OVERNIGHT PERIOD TO IFR, WITH SOME LOCATIONS
DROPPING DOWN TO LIFR BY THURSDAY MORNING. CEILINGS WILL LIFT A
LITTLE BIT TOWARD THURSDAY AFTERNOON AND WINDS WILL INCREASE OUT OF
THE SOUTH SOUTHWEST WITH SPEEDS AROUND 10 KNOTS OR LESS. WHILE THE
WINDS WILL HELP TO PROMOTE A LITTLE BIT OF MIXING, CONFIDENCE IS
PRESENTLY LOW THAT CEILINGS WILL LIFT ENOUGH TO BECOME VFR FOR THE
AFTERNOON/EVENING HOURS.

PLENTY OF LOW LEVEL MOISTURE WILL ACROSS THE REGION AND AS A
SHORTWAVE AND WEAK WARM FRONT MOVE INTO THE AREA, WE MAY SEE SOME
LIGHT RAIN AND/OR DRIZZLE OVERNIGHT THROUGH THURSDAY LATE MORNING.

OUTLOOK...
THU THRU SAT MORNING...LOW CIGS/VSBYS EXPECTED MUCH OF THE TIME.
PERIODS OF RAIN WHICH MAY CHANGE TO SNOW BEFORE ENDING EARLY SAT,
ESPECIALLY THE NORTHERN TAF SITES.
SAT AFTERNOON THRU SUN MORNING...MOSTLY VFR.
SUN AFTERNOON...DETERIORATING CIGS/VSBYS. PERIODS OF SNOW SLEET
AND RAIN.
SUN NIGHT THRU MONDAY...MAINLY IFR CONDITIONS AS A WARM FRONT LIFTS
NORTH THROUGH THE REGION. PRECIPITATION CHANGES TO RAIN...THEN BACK
TO A FROZEN FORM LATER MONDAY.
&&


.MARINE...
SUB ADVISORY CONDITIONS ARE EXPECTED THROUGH THURSDAY.

WINDS REMAIN FAIRLY LIGHT ACROSS THE AREAS WATERS WITH SEAS
REMAINING AROUND 3 FEET OR LESS. WINDS AND SEAS WILL START TO
INCREASE AS WE HEAD INTO THURSDAY NIGHT IN ADVANCE OF AN
APPROACHING COLD FRONT.

OUTLOOK...
SCA FLAG WILL PROBABLY BE NEEDED BY THU NIGHT FOR INCREASING
WINDS/SEAS. WINDS/SEAS MAY REMAIN SCA CRITERIA INTO THE WEEKEND.
&&

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

&&

$$
SYNOPSIS...MIKETTA
NEAR TERM...MEOLA
SHORT TERM...MEOLA
LONG TERM...MIKETTA
AVIATION...MEOLA/MIKETTA
MARINE...MEOLA/MIKETTA