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000
FXUS61 KPHI 090544
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1244 AM EST MON DEC 9 2013

.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL MOVE THROUGH THE GREAT LAKES REGION
THROUGH MONDAY, DRAGGING A COLD FRONT THROUGH OUR AREA LATE
MONDAY. MEANWHILE, A LOW PRESSURE SYSTEM WILL DEVELOP AND MOVE UP
ALONG THE MIDDLE ATLANTIC COAST ON MONDAY. A SECONDARY FRONT WILL
MOVE THROUGH THE REGION LATE TUESDAY INTO WEDNESDAY. HIGH PRESSURE
WILL THEN BUILD INTO THE REGION FROM THE WEST ON WEDNESDAY BEFORE
SHIFTING EAST OF THE AREA AT THE END OF THE WEEK.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
MADE SOME ADJUSTMENTS TO HEADLINES BASED ON TEMPS. LOWERED THE
ADVY FOR MOST OF THE ERN SHORE AND ANOTHER PIECE OF SERN NJ.  THE
CURRENT THINKING IS THAT PRECIP WILL CHANGE TO RAIN AS TEMPS
SLOWLY RISE, HOWEVER THIS HAS BEEN THE THINKING ALL DAY LONG AND
THE TRANSITION HAS BEEN MUCH SLOWER THAN ANTICIPATED. LATEST RADAR
SHOWED THE BULK OF THE PRECIP OVER SRN PORTIONS OF THE AREA MOVG
NE, MOST AMTS HAVE BEEN FAIRLY LIGHT ELSEWHERE. THE BULK OF THE
PRECIP HAS BEEN FZDZ OR FZRA WHERE TEMPS ARE AOB FREEZING.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TUESDAY/...
THE ACTIVE WEATHER SHOULD BE TAPERING DOWN AS WE GO THROUGH MONDAY.
THIS IS AS LOW PRESSURE LIFTS ACROSS THE GREAT LAKES AND INTO
SOUTHEASTERN CANADA, AND A SECONDARY LOW NEAR THE TRIPLE POINT LIFTS
TOWARD SOUTHEASTERN NEW ENGLAND THROUGH THE EARLY AFTERNOON. THIS
SHOULD RESULT IN THE LARGE SCALE LIFT GRADUALLY WANING, WITH
PRECIPITATION GRADUALLY COMING TO AN END. THERE MAY BE SOME LINGERING
ICING ACROSS THE POCONOS AND WILL RUN THE ADVISORY UNTIL 9 AM MONDAY.
A WEAK COLD FRONT WILL THEN PUSH IN FROM THE WEST AND EFFECTIVELY
PUT AN END TO PRECIPITATION, BUT IN DOING SO COLDER AIR BEGINS TO
FILTER BACK INTO THE REGION.

NO MAJOR CHANGES WERE MADE TO THIS TIME FRAME ATTM.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
NOT MANY CHANGES TO THE EXTENDED DUE TO ONGOING WEATHER IN THE
NEAR/SHORT TERM PORTION OF THE FORECAST. BLENDED IN SOME NEWER
GUIDANCE TO THE FORECAST AND ADJUSTED POPS FOR THE TUESDAY EVENT.

MODELS CONTINUE TO SHOW A DISCONTINUITY WITH EACH OTHER IN TERMS OF
THE FINAL WAVE ON TUESDAY...DOES IT SKIRT BY TO OUR SOUTH OR HAVE
ENOUGH LATITUDE TO BRUSH BY OVERHEAD. UPPER LEVEL SUPPORT IN TERMS
OF THE RIGHT ENTRANCE TO THE STRONG JET AND WEAK Q-VEC CONVERGENCE
COUPLED WITH WEAK FGEN IN THE 700-500MB LAYER, SHOULD ALLOW FOR SOME
MORE MOISTURE TO BE SQUEEZED OUT ACROSS AT LEAST THE SOUTHERN HALF
OF THE CWA TUESDAY AFTERNOON. THERMAL PROFILES WILL BE CONDUCIVE FOR
ALL SNOW TO FALL THOUGH THE ONE MAJOR QUESTION BECOMES HOW MUCH
ENERGY IS STILL LEFT IN THE MID-LEVELS. BY TUESDAY THE MID-LEVEL
ENERGY BECOMES VERY STRUNG OUT AND MAY HAVE GIVEN ALL IT CAN SO ONLY
TIME WILL TELL IN THE AFTERMATH OF TONIGHTS SYSTEM TO SEE IF IF CAN
RECOVER. SPEAKING OF SNOWFALL, NOT EXPECTING MUCH IN THE WAY OF
ACCUMULATION THOUGH SOME OF THE MODELS ARE TRYING TO SHOW A QUICK
BURST TUESDAY AFTERNOON WITH DECENT DENDRITIC GROWTH POSSIBLE WITH
UPWARDS OF AN INCH IN SPOTS...MOST SOUTH AND EAST OF PHILLY.

WITH THE FINAL WAVE GONE, HIGH PRESSURE WORKS BACK IN ON WEDNESDAY
AND TEMPERATURES PLUMMET TO WELL BELOW SEASONAL AVERAGES...THROUGH
AT LEAST THE END OF THE WORK WEEK. A SLIGHT MODERATION IS EXPECTED
BY SATURDAY AS THE FLOW BEGINS TO VEER SLIGHTLY TOWARDS THE
WEST-SOUTHWEST. THE NEXT POTENTIAL SYSTEM LOOKS TO SKIRT BY THE
COAST SATURDAY NIGHT INTO SUNDAY THROWING SOME MOISTURE BACK ACROSS
THE REGION.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

TONIGHT...A TRANSITION OF THE PRECIPITATION IS GRADUALLY
OCCURRING FROM SOUTHEAST TO NORTHWEST, WITH SOME SLEET CHANGING TO
FREEZING RAIN/FREEZING DRIZZLE AND THEN RAIN. KABE AND KRDG WILL
HANG ONTO THE FROZEN/FREEZING PRECIPITATION THE LONGEST, WITH KMIV
AND KACY HAVING ALL RAIN SOONER. MVFR TO EVEN IFR CONDITIONS
/ESPECIALLY CEILINGS/ ARE EXPECTED. NORTHEAST WINDS GENERALLY
AROUND 5 TO 10 KNOTS, HOWEVER BECOMING EAST-SOUTHEAST MAINLY AT
KACY OVERNIGHT.

MONDAY...SOME LIGHT RAIN WILL CONTINUE THROUGH THE MORNING TO
EARLY AFTERNOON ACROSS THE REGION, WITH ANY IFR CONDITIONS
GRADUALLY IMPROVING TO LOW-END MVFR. MAINLY SOUTHEAST WINDS UNDER
10 KNOTS ARE EXPECTED THROUGH THE DAY, BECOMING MORE SOUTHWEST TO
WEST LATE.

OUTLOOK...
MONDAY NIGHT THROUGH TUESDAY...MVFR TO VFR CONDITIONS ARE EXPECTED
AT THE TERMINALS. SNOW/RAIN IS POSSIBLE. BETTER CHANCES FOR
PRECIPITATION SOUTH AND EAST OF KPHL ON TUESDAY. NORTHWEST WINDS
AROUND 5 TO 10 KNOTS.

WEDNESDAY...MAINLY VFR CONDITIONS EXPECTED. WEST WINDS AROUND 10 TO
15 KNOTS WITH GUSTS UP AROUND 20 KNOTS.

THURSDAY AND FRIDAY...MAINLY VFR CONDITIONS EXPECTED. WEST TO
NORTHWEST WINDS AROUND 10 KNOTS OR LESS.

&&

.MARINE...
WITH BUOY 44009 STILL HAVING SEAS AROUND 6 FT, EXTENDED THE SCA
FOR THE SRN WATERS AND FOR THE SAKE OF CONSISTENCY SAKE ALL OF THE
OCEAN NOW HAS AN EXPIRATION TIME OF 12Z. CAN MAKE FURTHER
REFINEMENTS LATER.

OUTLOOK...
MONDAY NIGHT THROUGH AND WEDNESDAY...A FAIRLY TIGHT GRADIENT WILL
EXIST FOR THE MONDAY NIGHT THROUGH WEDNESDAY TIME FRAME WITH WINDS
PICKING UP OUT OF THE WEST OR NORTHWEST. WE SHOULD HAVE ENOUGH
MIXING TO BRING SOME HIGHER WINDS FROM ALOFT TO THE SURFACE AND WE
MAY NEAR GALE FORCE GUSTS TUESDAY NIGHT AND WEDNESDAY MORNING,
ESPECIALLY ACROSS THE NORTHERN OCEAN WATERS. CONFIDENCE IS HIGH
THAT A SMALL CRAFT WILL BE NEEDED BUT NOT THAT HIGH FOR POTENTIAL
GALES.

THURSDAY AND FRIDAY...WINDS AND SEAS WILL SUBSIDE BELOW SMALL CRAFT
ADVISORY LEVELS AS HIGH PRESSURE BUILDS ACROSS THE REGION AND REMAIN
BELOW AS WE END THE WORK WEEK.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR
     PAZ060>062-101-103>106.
     WINTER WEATHER ADVISORY UNTIL 5 AM EST EARLY THIS MORNING FOR
     PAZ070-071-102.
     WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR PAZ054-
     055.
NJ...WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR
     NJZ007>009.
     WINTER WEATHER ADVISORY UNTIL 5 AM EST EARLY THIS MORNING FOR
     NJZ010-012-013-015>020-027.
     WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR NJZ001.
DE...WINTER WEATHER ADVISORY UNTIL 5 AM EST EARLY THIS MORNING FOR
     DEZ001.
MD...WINTER WEATHER ADVISORY UNTIL 5 AM EST EARLY THIS MORNING FOR
     MDZ008.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST THIS MORNING FOR
    ANZ450>455.
&&

$$
SYNOPSIS...HEAVENER/MEOLA
NEAR TERM...AMC/GORSE/KLINE/NIERENBERG
SHORT TERM...GORSE
LONG TERM...HEAVENER/MEOLA
AVIATION...GORSE/HEAVENER/KLINE/MEOLA
MARINE...GORSE/HEAVENER/MEOLA/NIERENBERG