FXUS61 KBOX 260015
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
715 PM EST FRI DEC 25 2009

.SYNOPSIS...
LOW PRESSURE OVER THE CAROLINAS WILL MOVE UP THE ATLANTIC COAST
BRINGING SOME FREEZING PRECIPITATION TO SOUTHERN NEW ENGLAND TONIGHT
INTO SATURDAY...THEN RAIN LATE SATURDAY INTO EARLY SUNDAY. ANOTHER 
WEAK LOW PRESSURE SYSTEM WILL LIKELY BRING SOME LIGHT SNOW TO THE
REGION ON MONDAY. VERY COLD AND BLUSTERY WEATHER WILL FOLLOW IN THE
WAKE OF THIS LOW MONDAY NIGHT INTO WEDNESDAY. A COASTAL STORM MAY
BRING MORE WINTRY PRECIPITATION TO THE REGION AROUND NEW YEARS DAY.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...

RIBBON OF LOW LEVEL MOISTURE EMANATING FROM THE ATLANTIC HAS MOVED
ASHORE AS EXPECTED THIS EVENING. HOWEVER...THE PRECIP IS MORE OF A
MIXTURE OF SNOW AND DRIZZLE AT THIS TIME. AS OF 00Z...ORH AND FIT
HAVE DROPPED TO AROUND 2SM IN -SN. DUE TO THE MIXTURE OF
PRECIPITATION...WE HAVE TRANSITIONED THE FREEZING RAIN ADVISORY TO A
WINTER WEATHER ADVISORY. WE DO THINK FREEZING DRIZZLE WILL BECOME
PREDOMINANT LATER TONIGHT...BUT FOR NOW...ACROSS THE INTERIOR...IT
LOOKS AS THOUGH LIGHT SNOW WILL CONTINUE TO FALL FOR AWHILE. NOT
EXPECTING MUCH IN THE WAY OF ACCUMULATIONS...BUT A COATING WILL BE
POSSIBLE...ESPECIALLY IN THE AREA NORTH OF THE MASS PIKE AND WEST OF
I-495.

PREVIOUS DISCUSSION...

SOMEWHAT COMPLEX FORECAST IN THE NEAR TERM. SKIES HAVE CLOUDED UP AS
EXPECTED OVER SOUTHERN NEW ENGLAND. DAYTIME TEMPERATURES WERE HELD TO
THE LOWER AND MID 30S IN MUCH OF THE AREA...AND AS OF 430 PM...MUCH OF
SOUTHERN NH...WESTERN AND CENTRAL MA...AND NORTHERN CT...WAS AT OR
BELOW THE FREEZING MARK. 

LOTS OF PRECIPITATION ON RADAR TO OUR SOUTHWEST LATE THIS AFTERNOON...
BUT AMOUNTS HAVE ONLY RANGED FROM A TRACE TO 0.05 INCHES IN NJ AND
EASTERN PA TODAY. TAUNTON RADAR HAS BEGUN TO SHOW SOME RETURNS OVER
CAPE COD BAY IN THE PAST HOUR AND THIS IS THE BEGINNING OF A GRADUAL
INCREASE IN LOW LEVEL MOISTURE FOR SOUTHERN NEW ENGLAND TONIGHT.

THE AIR ABOVE 850 MB IS EXTREMELY DRY. THIS WAS A BIG FACTOR IN THE
FORECAST DECISION MAKING. ALTHOUGH PARTIAL THICKNESSES ARE COLD
ENOUGH FOR SNOW AND SLEET...IT IS FELT THAT THE FORCING WILL ONLY BE
IN THE LOWEST LEVELS AND THUS NOT DEEP ENOUGH MOISTURE FOR MANY
RAINDROPS...AND THUS NOT MUCH IN THE WAY OF SLEET WHICH IS FROZEN
RAINDROPS. THINK THAT OUR BIGGEST ISSUE FOR TONIGHT IS THE
DEVELOPMENT OF FREEZING DRIZZLE. AT FIRST...RESTRICTED THIS TO 06Z 
BUT SEEING THE DEVELOPMENT OVER CAPE COD BAY...BACKED THIS UP TO 03Z.
SNOW GRAINS MAY OCCUR TOO BUT ARE NOT EXPLICITLY IN FORECAST.

HAVE ISSUED A FREEZING RAIN ADVISORY BUT EXPLAINED THAT WHILE SOME
PLACES MAY RECEIVE A FEW HUNDREDTHS OF FREEZING RAIN...THE ADVISORY
IS FOR FREEZING DRIZZLE. IT COVERS NW RI...NORTHERN CT...MUCH OF MA
EXCEPT ALONG THE IMMEDIATE COAST AND INTERIOR SE MA...AND SW NH.  
UNTREATED ROADS AND SIDEWALKS COULD BECOME EXTREMELY SLICK AND
DANGEROUS OVERNIGHT.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
PREVIOUS DISCUSSION...

A CLOUDY DAY IS FORECAST FOR SATURDAY WITH AREAS OF FREEZING RAIN AND
FREEZING DRIZZLE IN THE MORNING...EXCEPT JUST PLAIN DRIZZLE IN
SOUTHERN AREAS. THEN A STEADIER RAIN SHOULD MOVE IN AS LOW PRESSURE
GETS CLOSER AND LOW LEVEL SOUTHEAST WINDS REALLY PICK UP... TO 50-60
KNOTS AT 925 MB OVER THE CAPE AND ISLANDS BY SAT NIGHT. THE GOOD NEWS
IS THAT THIS SHOULD SLOWLY LEAD TO A RISE IN TEMPERATURES...TO ABOVE
FREEZING EVEN IN SOUTHERN NEW HAMPSHIRE BY NIGHTFALL OR SOONER. THE
HEAVIEST PRECIPITATION ARRIVES DURING SAT NIGHT AND EXITS THE WESTERN
AND CENTRAL AREAS BY DAYBREAK SUNDAY. LESS THAN AN INCH OF RAIN IS
EXPECTED AND THE SNOW PACK SHOULD BE ABLE TO ABSORB A LOT OF THE RAIN.
NEVERTHELESS...THIS SHOULD LEAD TO SOME LOCAL DRAINAGE PROBLEMS
ESPECIALLY IN URBAN AREAS. 

ONE MAJOR CONCERN IS THAT IF TEMPERATURES DO NOT WARM AS MUCH AS
EXPECTED...THAT THE HEAVIER RAIN LATE SAT AFTERNOON AND NIGHT COULD
FALL IN THE FORM OF FREEZING RAIN...WHICH WOULD RESULT IN BAD ICING
CONDITIONS. THIS IS CONSIDERED A LOW RISK AT THE MOMENT...BUT
SOMETHING THAT SUBSEQUENT SHIFTS WILL NEED TO MONITOR CLOSELY.

NON DIURNAL TEMPERATURE TRACE FORECAST FOR SAT NIGHT...WITH
TEMPERATURES RISING THROUGH THE 40S TO NEAR 50 IN SOUTHEAST MA AND TO
35 TO 40 IN SOUTHERN NH. IT WILL BECOME RATHER WINDY NEAR THE COAST SAT
NIGHT BUT THE STRONGEST WINDS SHOULD BE CONFINED TO THE COASTAL WATERS.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
LOW PRESSURE WILL CROSS NEW ENGLAND SUNDAY...BRINGING AND END TO ANY
RAIN OR PATCHY FREEZING RAIN DURING THE MORNING. SUNDAY AFTERNOON MAY
ACTUALLY BE QUITE NICE AS DRY SLOT LOOKS TO ADVECT IN AND ALLOW FOR A
GOOD AMOUNT OF SUNSHINE AND ABOVE NORMAL TEMPERATURES.

A STRONG SHORT WAVE TROUGH WILL MOVE TOWARD SOUTHERN NEW ENGLAND
SUNDAY NIGHT. IT LOOKS AS THOUGH ENOUGH MOISTURE AND ASCENT WILL
DEVELOP TO ALLOW LIGHT SNOW TO DEVELOP LATE SUNDAY NIGHT OR EARLY
MONDAY MORNING...LASTING THROUGH MID AFTERNOON OR SO. THERE IS STILL
A CHANCE THAT MUCH OF THE PRECIP WITH THIS SYSTEM REMAINS TO OUR
SOUTH...BUT IT LOOKS LIKE LOCATIONS MAINLY SOUTH OF THE MASS PIKE
COULD SEE 1-2 INCHES OF SNOW...WITH LOCALLY HIGHER AMOUNTS IF MORE
ATLANTIC MOISTURE CAN GET WRAPPED BACK INTO THE SYSTEM BEFORE IT
MOVES OUT TO SEA. WE WENT WITH LIKELY POPS SOUTH OF THE PIKE...WITH
CHANCE NORTH. SOUTHEASTERNMOST MASS AND COASTAL RI MAY BE WARM ENOUGH
IN THE BOUNDARY LAYER FOR A MIX WITH RAIN.

AFTER THIS SYSTEM DEPARTS LATE MONDAY...THE NEXT SHORT WAVE WILL BE
QUICK TO APPROACH...AND THIS ONE WILL HELP DRIVE AN ARCTIC FRONT
ACROSS SOUTHERN NEW ENGLAND MONDAY NIGHT. VERY COLD AND WINDY
CONDITIONS WILL FOLLOW IN THE WAKE OF THIS FRONT FOR TUESDAY AND
TUESDAY NIGHT. WIND CHILLS WILL LIKELY DROP BELOW ZERO DURING THIS
TIME. WE CAN/T RULE OUT A FEW SNOW SQUALLS WITH THE PASSAGE OF THE
FRONT MONDAY NIGHT.

SFC HIGH PRESSURE LOOKS TO CREST OVER SNE ON WEDNESDAY...ALLOWING FOR
DIMINISHING WINDS AND SLOWLY MODERATING TEMPERATURES.

THE MODELS CONTINUE TO ADVERTISE AT LEAST THE POTENTIAL FOR A
SIGNIFICANT COASTAL STORM TO AFFECT SOUTHERN NEW ENGLAND SOMETIME
BETWEEN FRIDAY AND SUNDAY. THIS WILL ALL DEPEND ON THE
STRENGTH/ORIENTATION/AND POSITION OF SHORT WAVES A GOOD 7 DAYS
AWAY...THEREFORE WE ONLY HAVE LOW CONFIDENCE THAT SUCH STORM WOULD
OCCUR.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
TONIGHT...MODERATE TO HIGH CONFIDENCE AREAS IFR CEILINGS DEVELOP AOB
1000 FT NEAR OR SHORTLY AFT 03Z ACROSS THE INTERIOR. SPOTTY LIGHT
SNOW AND LIGHT FREEZING DRIZZLE ACROSS THE INTERIOR TERMINALS.

SATURDAY...MODERATE TO HIGH CONFIDENCE MVFR CIGS COAST/AREAS IFR
CIGS INTERIOR WITH -DZ COAST AND -FZDZ INLAND THE MORNING. PATCHY
MVFR VSBYS 3-5 SM IN FOG PATCHES. PRECIPITATION SHOULD BECOME STEADY
AFT 21Z ACROSS THE WEST. PRECIPITATION OVERSPREADING THE AREA DURING
THE EVENING AND AT NIGHT.

SATURDAY NIGHT...IFR CIGS AND VSBYS IN RAIN.

OUTLOOK...SUNDAY THROUGH WEDNESDAY...

SUNDAY...MVFR/IFR CONDITIONS IMPROVE TO VFR BY MIDDAY IF NOT SOONER.

MONDAY...MVFR CONDITIONS POSSIBLE IN LIGHT SNOW...ESPECIALLY ALONG
AND SOUTH OF THE MASS PIKE.

TUESDAY...VFR...GUSTY NW WINDS.

WEDNESDAY...VFR WITH DIMINISHING WINDS.

&&

.MARINE...
TONIGHT... EAST WINDS AND SEAS INCREASE DURING THE NIGHT WITH SMALL
CRAFT CONDITIONS EXPANDING CLOSER TO SHORE ESPECIALLY ON THE SOUTHERN
WATERS. SEAS STILL RUNNING 5 FT AT BOSTON BUOY AND 7 FT SEAS JUST OFF
OF GLOUCESTER.

SATURDAY AND SATURDAY NIGHT...EAST TO SOUTHEAST WINDS INCREASE TO 25
TO 30 KT WITH GUSTS TO GALE FORCE OVER THE SOUTHERN COASTAL WATERS
BY SATURDAY NIGHT. HAVE EXPANDED THE GALE WATCH TO INCLUDE THE WATERS
SOUTH AND EAST OF MARTHAS VINEYARD AND NANTUCKET. STILL FAR ENOUGH
OUT FOR SUBSEQUENT SHIFTS TO DETERMINE WHETHER TO UPGRADE TO A GALE
WARNING.

OUTLOOK...SUNDAY THROUGH WEDNESDAY...

SUNDAY...GALE FORCE SOUTHEASTERLIES WILL QUICKLY DIMINISH DURING THE
MORNING HOURS. HOWEVER...SEAS WILL REMAIN HIGH.

MONDAY...SMALL CRAFT CONDITIONS POSSIBLE...BUT LULL IN WINDS LIKELY
AS WEAK LOW PRESSURE MOVES ALMOST DIRECTLY OVERHEAD.

MONDAY NIGHT THROUGH WEDNESDAY...NW GALES LIKELY...THE STRONGEST OF
WHICH WILL PROBABLY OCCUR DAYTIME TUESDAY.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...WINTER WEATHER ADVISORY UNTIL 11 AM EST SATURDAY FOR 
     CTZ002>004.
MA...WINTER WEATHER ADVISORY UNTIL 11 AM EST SATURDAY FOR 
     MAZ002>006-008>013-026.
NH...WINTER WEATHER ADVISORY UNTIL 11 AM EST SATURDAY FOR NHZ011-
     012-015.
RI...WINTER WEATHER ADVISORY UNTIL 11 AM EST SATURDAY FOR RIZ001-
     003.
MARINE...GALE WATCH FROM SATURDAY AFTERNOON THROUGH LATE SATURDAY NIGHT 
     FOR ANZ232-235-255-256.
     SMALL CRAFT ADVISORY FROM 1 AM TO 4 PM EST SATURDAY FOR 
     ANZ230>237.
     SMALL CRAFT ADVISORY UNTIL 4 PM EST SATURDAY FOR ANZ250-251-
     254>256.

&&

$$
SYNOPSIS...EKSTER/GAF
NEAR TERM...EKSTER/GAF
SHORT TERM...GAF
LONG TERM...EKSTER
AVIATION...EKSTER/STRAUSS/GAF
MARINE...EKSTER/GAF