-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KBOX 120753
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
353 AM EDT WED MAR 12 2014

.SYNOPSIS...
A STRONG COASTAL STORM WILL TRACK ACROSS THE SOUTHERN
NEW ENGLAND COAST WED INTO EARLY THU. HEAVY RAIN WILL BE THE PRIMARY
PRECIPITATION TYPE...EXCEPT ACROSS FAR NORTHWEST MASSACHUSETTS AND
SOUTHWEST NEW HAMPSHIRE WHERE A WINTRY MIX IS LIKELY WED BEFORE
CHANGING OVER TO SNOW WEDNESDAY NIGHT. MOST LOCATIONS WILL END AS A
BIT OF SNOW THURSDAY MORNING...BUT THE HIGHLIGHT THURSDAY WILL BE AN
ARCTIC SURGE OVERSPREADING THE REGION ON STRONG NORTHWEST WINDS.
MILDER WEATHER RETURNS FRI AND SAT...BEFORE ANOTHER INSTALLMENT OF
COLDER AIR ARRIVES SUNDAY INTO EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
940 PM UPDATE...

TEMPS THIS EVENING HAVE QUICKLY DROPPED BACK INTO THE 30S TO MIDDLE
40S IN MOST LOCALES AFTER A MILD AFTERNOON.  JUST SOME HIGH CLOUDS
AND LIGHT WINDS HAVE ALLOWED THE QUICK DROP IN TEMPS TO OCCUR.

THICKER MID LEVEL CLOUDINESS WILL BEGIN TO SPILL INTO THE REGION
OVER THE NEXT SEVERAL HOURS FROM THE WEST.  THEREFORE...LOW TEMPS
MAY ONLY DROP A FEW MORE DEGREES AND EVENTUALLY LEVEL OFF IN SOME OF
THE AREAS THAT HAVE RADIATED OUT QUICKLY.  EXPECT MOST LOCATIONS TO
BE IN THE 30S BY DAYBREAK WEDNESDAY.

LOW LEVEL DRY AIR IN PLACE WILL KEEP THE BULK OF THE PRECIPITATION
UNTIL AFTER 12Z WED.  HOWEVER...WARM ADVECTION ALOFT MAY ALLOW SOME
LIGHT SCATTERED PRECIPITATION TO DEVELOP ACROSS PORTIONS OF WESTERN
MA/SOUTHWEST NH BETWEEN 9Z AND 12Z.  PTYPE WILL PROBABLY BE MAINLY
LIGHT RAIN...BUT SOME POCKETS OF LIGHT SNOW WILL BE POSSIBLE IN
SOUTHWEST NH.  THERE ALSO IS A LOW PROBABILITY FOR A TOUCH OF LIGHT
FREEZING RAIN...BUT TEMPS APPEAR TOO MARGINAL RIGHT NOW FOR A BIG
THREAT.  WILL CONTINUE TO MONITOR CLOSELY.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM THURSDAY/...
* STORM CONTINUES TO TREND TOWARD A WARMER OUTCOME

11/12Z MODEL GUIDANCE CONTINUES TO FAVOR A WARMER SOLUTION. STAYED
CLOSE TO MODEL CONSENSUS FOR TRACK. AT THIS TIME...THE LOW TRACK
WOULD MOVE FROM NEW YORK CITY TO NEAR THE CAPE COD CANAL BEFORE
MOVING OFFSHORE. HAVE THE GREATEST CONFIDENCE IN WINTER WEATHER
ADVISORIES AT THIS TIME...SO THAT IS WHAT WE HAVE DONE WITH THIS
AFTERNOON PACKAGE. WILL NEED TO KEEP A VERY CLOSE EYE ACROSS
SOUTHERN NH AND NORTHWEST MA. IT IS STILL POSSIBLE THESE AREAS
COULD BE UPGRADED TO WARNINGS SHOULD THE TRANSITION TO SNOW OCCUR
MORE QUICKLY THAN CURRENTLY FORECAST.

MOISTURE IS NOT REALLY GOING TO AN ISSUE. THERMAL PROFILES WILL BE
CRITICAL. EXPECTING RAINFALL TO BECOME MORE WIDESPREAD DURING THE
DAY WEDNESDAY...WITH THE MAJORITY OF THE AREA EXPERIENCING
PRECIPITATION BY LATE IN THE DAY. TEMPERATURES SHOULD RISE ENOUGH
TO BE ALL RAIN FOR MOST OF THE DAY...WITH THE EXCEPTION OF AREAS
NORTH OF ROUTE 2 IN MA AND NH. THOSE AREAS COULD SEE SOME WINTRY
PRECIPITATION IN THE MORNING. RAINFALL WILL LIKELY BE HEAVIER AT
TIMES.

STRONG COLD AIR ADVECTION WEDNESDAY NIGHT ON THE BACKSIDE OF THE
PRECIPITATION WILL TRANSITION ALL PRECIPITATION BACK TO SNOW.
CANNOT RULE OUT A PERIOD OF SLEET OR FREEZING RAIN. TEMPERATURES
WILL PLUMMET...WHICH COULD LEAD TO A RAPID FREEZE LATE WEDNESDAY
NIGHT INTO THURSDAY MORNING. FOR SOME /ESPECIALLY CT...RI...
SOUTHERN MA/ THIS MAY ACTUALLY BE THE BIGGER ISSUE WHERE ANY
STANDING WATER/WET ROADWAYS ARE OBSERVED.

DID NOT USE A DIURNAL TREND WEDNESDAY NIGHT INTO THURSDAY.
THINKING HIGHS FOR THE CALENDAR DAY THURSDAY WILL BE NEAR OR
SHORTLY AFTER MIDNIGHT THURSDAY...THEN FALLING THEREAFTER.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
-- Changed Discussion --
*** TYPICAL MARCH WEATHER WITH A MIX OF SPRING AND WINTER-LIKE
    TEMPS THIS PERIOD ***

OVERVIEW AND MODEL PREFERENCES...
12.00Z MODEL GUIDANCE SUITE IS IN FAIRLY GOOD SYNOPTIC SCALE
AGREEMENT THROUGH THE WEEKEND AT LEAST BUT THEN BEGINS TO SHOW
TYPICAL SPREAD/BIASES BY EARLY TO MID NEXT WEEK.

THE KEY TO THE EXTENDED PERIOD WILL BE AN ARCTIC CUTOFF...THAT IS
A PIECE OF THE POLAR VORTEX WHICH WILL GRADUALLY SETTLE ACROSS
NORTHERN QUEBEC. THIS WILL BE EMBEDDED WITHIN A GENERAL POSITIVE
NAO/AO REGIME...SUGGESTING A PROGRESSIVE STORM TRACK FROM THE ERN
CONUS INTO THE NRN ATLANTIC. THEREFORE...THE KEY TO THE ULTIMATE
STORM TRACK FOR EARLY NEXT WEEK WILL BE EXACTLY WHERE THE VORTEX
AND ITS LONGWAVE TROF EXTENSION INTO THE ERN CONUS SETS UP. LATEST
ECMWF AS WELL AS SOME OF THE GEFS/ECENS MEMBERS SUGGEST A SLIGHTLY
LESS PROGRESSIVE TRACK...ALLOWING THE TROF TO SET UP MAINLY FROM
THE GREAT LAKES INTO THE GULF OF MEXICO...PICKING UP ENERGY AND
MOISTURE AS IT DOES. IT IS THIS SOLUTION THAT WOULD BRING THE BEST
SHOT AT ANOTHER COASTAL STORM FOR EARLY NEXT WEEK. THE GFS
SOLUTION IS MORE PROGRESSIVE AND SUPPRESSED TO THE S. ONCE AGAIN
THOUGH...ASIDE FROM THE LONGWAVE TROF IT WILL REQUIRE ADDITIONAL
SHORTWAVE ENERGY...BOTH FROM ARCTIC THE NRN PACIFIC. EACH OF THESE
WAVES WILL NOT BE IN AN OBSERVATION RICH AREA FOR ABOUT 48+
HOURS...SO EXPECT THE TRACK TO SETTLE BETTER BY THE WEEKEND. FOR
NOW...WILL BLEND OPERATIONAL GUIDANCE TO TAKE INTO ACCOUNT ALL
POSSIBILITIES.

DETAILS...

THU NIGHT INTO FRI NIGHT...
MAINLY DRY WX THROUGH THE PERIOD AS A RIDGE OF HIGH PRES NOSES
OVER THE REGION FROM THE S. THU NIGHT IS EXPECTED TO START
COLD...WITH AMBIENT MINS DROPPING INTO THE SINGLE DIGITS AND LOW
TEENS. THIS WILL BE COMBINED WITH GUSTY NW WINDS AND MAY YIELD
WIND CHILLS APPROACHING -10F TO -15F...SO NOT OUT OF THE QUESTION
WIND CHILL ADVISORIES MAY BE NEEDED. OTHERWISE...TEMPERATURES
REBOUND BY FRI...SHIFTING INTO THE LOW TO UPPER 30S AND ONLY
DROPPING BACK INTO THE MID 20S TO LOW 30S THANKS TO INCREASING
CLOUDS FRI NIGHT.

SAT INTO SUN NIGHT...
MODERATING TEMPERATURES EXPECTED UNDER WEAK WARM ADVECTION AHEAD
OF A COLD FRONT SAT. THIS SHOULD ALLOW HIGHS TO REACH INTO THE MID
40S TO LOW 50S. THE COLD FRONT IS EXPECTED TO SLIDE THROUGH BY
AFTERNOON...LIFT WITH IT IS WEAK...MAINLY FROM THE ISENTROPIC
SUPPORT WITHIN THE WARM ADVECTION AHEAD OF IT. MOISTURE IS ALSO
LACKING...WITH ONLY ABOUT A QUARTER TO HALF INCH PWAT VALUES.
SO...A FEW SHOWERS MAY ACCOMPANY THIS FRONT AS IT PASSES...BUT
CERTAINLY NOT A WASHOUT AND SOME AREAS MAY STAY DRY ALTOGETHER.
COLD AND DRIER AIR SETTLES IN BEHIND THE FRONT SAT NIGHT INTO SUN
NIGHT. LOWS IN THE LOW TO UPPER 20S EXPECTED SAT NIGHT UNDER
CLOUD COVER AND HIGHS SUN ONLY IN THE 30S. ANOTHER ROUND OF COLD
MINS SUN NIGHT...SETTLING IN THE TEENS AND LOW 20S.

MON INTO TUE...
THE COLD FRONT SETTLES OFFSHORE SUN...ORIENTING ALONG THE MEAN
STORM TRACK...WHICH REMAINS A BIT IN QUESTION BASED ON THE
OVERVIEW DISCUSSION ABOVE. THERE ARE INGREDIENTS FOR ANOTHER
COASTAL WAVE OF LOW PRES TO DEVELOP...BUT ITS POTENCY AND TRACK
ARE UNCERTAIN. AS MENTIONED ABOVE...CURRENT ECMWF /AS WELL AS
GEFS/ECENS MEMBERS AND EVEN THE GLOBAL CMC/ SUGGEST IT MAY MAKE A
CLOSE ENOUGH PASS FOR SOME WRAP-AROUND SNOWS ACROSS SRN NEW
ENGLAND...BUT THE MORE PROGRESSIVE PATTERN /GFS AND SOME ENSEMBLE
MEMBERS/ WOULD KEEP IT TOO FAR OFFSHORE. WILL NEED TO MONITOR ONCE
SHORTWAVE ENERGY IN THE PACIFIC AND ARCTIC ARE BETTER SAMPLED.

TOWARD THE MIDDLE OF NEXT WEEK...
IN EITHER CASE...ANOTHER ROUND OF ARCTIC HIGH PRES LOOKS TO
SETTLE ACROSS THE REGION AS ANY STORM SYSTEM MOVES FURTHER
OFFSHORE...SO A PERIOD OF TEMPERATURES BELOW NORMAL LOOKS
POSSIBLE.
-- End Changed Discussion --

&&

.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TONIGHT THROUGH THURSDAY/...MODERATE TO HIGH CONFIDENCE
IN TRENDS AND TIMING.

TODAY...LATEST GUIDANCE SUGGESTS THAT VFR CONDITIONS MAY HANG TOUGH
FOR MUCH OF THE MORNING ESPECIALLY ACROSS THE COASTAL PLAIN.  SHOULD
SEE CONDITIONS DETERIORATE TO MVFR AND THEN IFR LEVELS THIS
AFTERNOON/EARLY EVENING FROM NORTHWEST TO SOUTHEAST.  PTYPE
WILL BE RAIN ACROSS THE REGION.  IN FACT...THE STEADY RAIN
WILL NOT ARRIVE UNTIL THIS AFTERNOON IN MOST AREAS AND PERHAPS LATE
AFTERNOON/EARLY EVENING ALONG THE COASTAL PLAIN.

TONIGHT...MVFR TO IFR CONDITIONS.  RAIN TRANSITIONS TO SNOW FROM
NORTHWEST TO SOUTHEAST AS THE NIGHT WEARS ON.  A BRIEF PERIOD OF
SLEET/FREEZING RAIN IS POSSIBLE DURING THE TRANSITION ESPECIALLY
NORTH OF THE MA TURNPIKE.  NORTHERLY WINDS WILL GUST BETWEEN 20 AND
30 KNOTS BEHIND THE STORM BY LATE EVENING INTO THE OVERNIGHT HOURS.
IT WILL TAKE A FEW HOURS LONGER FOR WINDS TO BECOME NORTHERLY JUST
OFF THE DECK...SO LLWS HAS BEEN INCLUDED IN THE TAFS.

THURSDAY...MVFR TO IFR CONDITIONS IN SNOW SHOWERS IN THE MORNING
SHOULD IMPROVE SOME DURING THE AFTERNOON FROM WEST TO EAST.  EXPECT
CONDITIONS TO IMPROVE TO MVFR IF NOT VFR BY MID TO LATE AFTERNOON.
NORTHWEST WIND GUSTS OF 30 TO 45 KNOTS EXPECTED.

PRELIMINARY SNOWFALL FORECAST...

BOS...1 TO 2 INCHES OVERNIGHT/THU AM
PVD...1/2 TO 2 INCHES OVERNIGHT/THU AM
BDL...1/2 TO 2 INCHES OVERNIGHT/THU AM
ORH...1-3 INCHES LATE OVERNIGHT/THU AM
MHT...2-5 INCHES LATE OVERNIGHT/THU AM

KBOS TERMINAL...HIGH CONFIDENCE IN TAF THROUGH 15Z TODAY. MODERATE
CONFIDENCE THEREAFTER.  RAIN TRANSITIONS TO A BRIEF PERIOD OF
SLEET/FREEZING RAIN BETWEEN 4Z AND 6Z TONIGHT.  THEN A CHANGE TO ALL
SNOW BETWEEN 6Z AND 8Z.

KBDL TERMINAL...HIGH CONFIDENCE IN TAF THROUGH 12Z TODAY. MODERATE
CONFIDENCE THEREAFTER.  RAIN TRANSITIONS TO SNOW BETWEEN 2Z AND 5Z
TONIGHT WITH A BRIEF PERIOD OF SLEET/FREEZING RAIN POSSIBLE DURING
THE TRANSITION.

OUTLOOK...THURSDAY NIGHT THROUGH SUNDAY.

THU NIGHT THROUGH FRI NIGHT...HIGH CONFIDENCE.
MAINLY VFR. STRONG NW WINDS DIMINISH THU NIGHT THEN SHIFT BACK TO
THE SW ON FRI AND FRI NIGHT.

SAT...MODERATE CONFIDENCE.
MAINLY VFR...BUT OCCASIONAL MVFR POSSIBLE IN LIGHT RAIN/SNOW
SHOWERS AHEAD OF A COLD FRONT.

SUN...MODERATE CONFIDENCE.
MAINLY VFR...BUT LOW PROBABILITY OF A LATE DAY OCEAN LOW PRES
LEADING TO SOME SNOW SHOWERS PARTICULARLY SE MASS. MVFR/IFR WOULD
BE POSSIBLE SHOULD THIS OCCUR.
-- End Changed Discussion --

&&

.MARINE...
-- Changed Discussion --
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

HIGH CONFIDENCE.

RATHER TRANQUIL CONDITIONS TONIGHT. SOUTH WINDS INCREASE AHEAD OF
A DEVELOPING LOW PRESSURE WEDNESDAY...WITH BUILDING SEAS AS WELL.
SMALL CRAFT SHOULD EXERCISE CAUTION WELL BEFORE THE START TIME OF
THE GALES LATE WEDNESDAY INTO WEDNESDAY NIGHT.

OUTLOOK...THURSDAY THROUGH SUNDAY...

THURSDAY AND THURSDAY NIGHT...MODERATE CONFIDENCE
NW GALES LIKELY ALONG WITH MODERATE FREEZING SPRAY POSSIBLE BY
LATE DAY THU. VSBY REDUCED IN LIGHT SNOW DURING THE DAY. VERY
ROUGH SEAS ESPECIALLY SOUTH WATERS FROM LEFTOVER SOUTH SWELLS
COMBINING WITH NEW NW WIND WAVES.

FRI...MODERATE CONFIDENCE.
NW WIND BECOMING SW DURING THE AFTERNOON. A FEW GUSTS TO 25 KT
POSSIBLE DURING THE AFTERNOON...WITH SEAS REMAINING ELEVATED ABOVE
5 FT ESPECIALLY ON THE OCEAN WATERS.

FRI NIGHT INTO SAT...MODERATE CONFIDENCE.
SW WINDS SHIFT TO THE W DURING THE DAY SATE. GUSTS SHOULD
GENERALLY REMAIN BELOW SMALL CRAFT CRITERIA BUT A BUILDING SWELL
OF 5-7 FT EXPECTED ON THE OCEAN WATERS.

SUN...
MODEST NW WIND MAY INCREASE BY SUN EVENING. DRY AND GOOD VSBY.
-- End Changed Discussion --

&&

.TIDES/COASTAL FLOODING...
NO FLOODING EXPECTED GIVEN RELATIVELY LOW ASTRO TIDES AND NOT MUCH
WIND AND SURGE ANTICIPATED AS TRACK OF SURFACE LOW PRESSURE LOOKS
TO BE DIRECTLY OVER SRN NEW ENGLAND. THIS WILL LIMIT THE ABILITY
FOR FETCH IN ANY ONE DIRECTION.

&&

.CLIMATE...
-- Changed Discussion --
NEAR RECORD COLD POSSIBLE THU NIGHT INTO EARLY FRIDAY. HERE ARE
RECORD LOW TEMPERATURES FOR FRIDAY MARCH 14TH...

BOSTON.......12/1896...FORECAST LOW...14
PROVIDENCE...12/1948...FORECAST LOW...13
BRADLEY ARPT..7/1948...FORECAST LOW...9
WORCESTER.....4/1948...FORECAST LOW...8
-- End Changed Discussion --

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CT...WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO NOON EDT
     THURSDAY FOR CTZ002>004.
MA...WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO NOON EDT
     THURSDAY FOR MAZ002-003.
     WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO NOON EDT
     THURSDAY FOR MAZ004>019-026.
NH...WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO NOON EDT
     THURSDAY FOR NHZ011-012-015.
RI...WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO NOON EDT
     THURSDAY FOR RIZ001>005.
MARINE...GALE WARNING FROM 8 AM TO 8 PM EDT THURSDAY FOR ANZ232>235-237-
     254>256.
     GALE WARNING FROM 5 AM TO 8 PM EDT THURSDAY FOR ANZ230-236.
     GALE WARNING FROM 2 AM TO 8 PM EDT THURSDAY FOR ANZ231-250-251.
-- End Changed Discussion --

&&

$$
SYNOPSIS...FRANK/DOODY
NEAR TERM...FRANK
SHORT TERM...FRANK
LONG TERM...DOODY
AVIATION...FRANK/DOODY
MARINE...FRANK/DOODY
TIDES/COASTAL FLOODING...STAFF
CLIMATE...STAFF