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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
448 AM EST SUN FEB 14 2016

.SYNOPSIS...

HISTORIC ARCTIC OUTBREAK FOR THE MODERN ERA CONTINUES THIS MORNING
WITH DANGEROUSLY COLD WIND CHILLS OF 25 TO 40 BELOW. WINDS DIMINISH
SOME LATER TODAY AND ESPECIALLY TONIGHT...BUT IT WILL REMAIN
BITTERLY COLD. A PERIOD OF ACCUMULATING SNOW IS THEN LIKELY FOR
MUCH OF REGION ESPECIALLY AWAY FROM THE COAST LATE MONDAY
AFTERNOON AND EVENING...CHANGING TO RAIN BY TUESDAY MORNING. A
POWERFUL STORM SYSTEM WILL LIKELY TRACK WEST OF NEW ENGLAND
TUESDAY INTO TUESDAY NIGHT BRINGING HEAVY RAIN...STRONG WINDS AND
WARM TEMPERATURES TO THE REGION. A TREND TOWARD DRIER AND COLDER
WEATHER FOLLOWS ON WEDNESDAY AND THURSDAY. ANOTHER WEATHER SYSTEM
WILL BRING SNOW AND RAIN TOWARD THE END OF THE WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...

***DANGEROUS WIND CHILLS OF 25 TO 40 BELOW ZERO THIS MORNING***

***HISTORIC ARCTIC OUTBREAK FOR THE MODERN ERA BRINGS THE COLDEST
  TEMPERATURES TO BOSTON AND WORCESTER SINCE 1957***

EXTREME ARCTIC OUTBREAK FOR SOUTHERN NEW ENGLAND STANDARDS CONTINUES
WITH TEMPS DOWN TO -15 IN WORCESTER AND -9 IN BOSTON AS OF 4 AM.
THESE ARE THE COLDEST READINGS RECORDED AT BOTH LOCATIONS SINCE
1957!  SO ITS FAIR TO SAY THAT THIS IS A HISTORIC ARCTIC OUTBREAK
FOR THE MODERN ERA.  A NEW RECORD WAS ALSO BROKEN WITH THE FEB
14/00Z UPPER AIR SOUNDING AT ALBANY. THE H850 TEMP WAS -30.8 C.
THE PREVIOUS RECORD COLD 850 MB TEMPERATURE WAS -30.5 C SET BACK ON
4 JANUARY 1981 AND ON 18 JANUARY 1982.

PUTTING THE RECORDS ASIDE...MAIN STORY THIS MORNING IS THE DANGEROUS
WIND CHILLS OF 25 TO 40 BELOW ZERO.  FROSTBITE CAN OCCUR ON EXPOSED
FLESH IN JUST 10 MINUTES.  MUCH OF THE REGION WILL SEE LOWS BETWEEN
10 AND 15 BELOW ZERO EARLY THIS MORNING WITH A FEW LOCATIONS NEAR -
20 ACROSS THE HIGHER TERRAIN.

OCEAN EFFECT SNOW SHOWERS FOR OUTER-CAPE...

WHILE THE REST OF THE REGION WAS CLEAR AND BITTERLY COLD...OCEAN
EFFECT SNOW SHOWERS HAVE DEVELOPED ACROSS THE OUTER-CAPE.  DESPITE
LIMITED FETCH WITH WINDS AT 300 TO 310 DEGREES...MID LEVEL TROUGH
SINKING SOUTH IS LIKELY AIDING IN SEEDER FEEDER PROCESSES.
ALSO...EXTREME INSTABILITY WITH NEARLY 1500 J/KG OF OCEAN INDUCED
CAPE IS LIKELY OVERCOMING THE VERY LIMITED FETCH.  SO FAR THE BULK
OF THE SNOW HAS BEEN NORTH OF ORLEANS AND ESPECIALLY IN THE
PROVINCETOWN AREA....BUT THE SNOW HAS RECENTLY SLIPPED SOUTH INTO
CHATHAM.  GIVEN LIMITED FETCH NOT EXPECTING MUCH MORE THAN FLURRIES
FROM HYANNIS TO THE UPPER CAPE.

SNOW AMOUNTS ACROSS THE OUTER-CAPE WILL VARY CONSIDERABLY OVER SHORT
DISTANCES AND WILL BE TOUGH TO MEASURE WITH THE STRONG WINDS.
OVERALL...A SWATH OF 1 TO 3 INCHES OF SNOW IS POSSIBLE THIS MORNING.
SHOULD SEE THE SNOW TAPER OFF THIS AFTERNOON...BUT LOW CLOUDS WILL
LINGER ACROSS THE OUTER-CAPE. THE BIGGEST CONCERN WILL PROBABLY BE
THE STRONG WINDS/BITTERLY COLD TEMPS WHICH WILL RESULT IN LOCALIZED
POOR VISIBILITY AT TIMES.  A SPECIAL WEATHER STATEMENT IS IN EFFECT.

THIS AFTERNOON...

WHILE IT STILL WILL BE BREEZY AND BITTERLY COLD...TEMPERATURES WILL
RECOVER ENOUGH TO ALLOW WIND CHILL HEADLINES TO EXPIRE THIS
AFTERNOON. 850 MB TEMPERATURES ONLY MODERATE TO -22C...SO HIGH TEMPS
WILL ONLY REACH INTO THE HIGH SINGLE DIGITS TO AROUND 10 ABOVE IN
MOST LOCATIONS. NEW RECORD LOW HIGH TEMPS WILL LIKELY BE SET IN
SOME LOCATIONS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...

***BITTERLY COLD TONIGHT BUT WITHOUT THE WIND***

HIGH PRESSURE BUILDING ACROSS SOUTHERN NEW ENGLAND WILL RESULT IN
LIGHT WINDS AND AN IDEAL NIGHT OF RADIATIONAL COOLING.  GIVEN THE
ARCTIC AIR FIRMLY IN PLACE ACROSS THE REGION...IT WILL BE ANOTHER
BITTERLY COLD NIGHT BUT WITH OUT THE WIND.  GUIDANCE TEMPS MAY BE
10+ DEGREES TOO WARM IN THE TYPICALLY PRONE OUTLYING LOCATIONS.
WOULD THINK WE SEE LOW TEMPS NEAR 20 BELOW ZERO IN THE TYPICALLY
COLDEST OUTLYING LOCATIONS OF WESTERN MA. MOST OTHER AREAS WILL
LIKELY SEE LOW TEMPS BETWEEN -5 AND -15...BUT SOME URBAN HEAT
ISLANDS WILL NOT GET QUITE THAT COLD.  ONE EXAMPLE IS BOSTON...WHICH
SHOULD SEE LOW TEMPS REMAIN ABOVE ZERO GIVEN LACK OF COLD ADVECTION
WITH THAT LOCATION NEEDS TO GET BELOW ZERO.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
HIGHLIGHTS...
* WINTRY MIX POSSIBLE MON NIGHT
* HEAVY RAIN EXPECTED ON TUE
* BRIEF COOL DOWN WED NIGHT INTO THU

OVERVIEW AND MODEL PREFERENCES...

ALTHOUGH CURRENT WESTERN HEMISPHERIC SETUP SHOWS NEGATIVE NAO/AO
AND POSITIVE PNA...WHICH HAS ALLOWED ARCTIC AIR TO SPILL SOMEWHAT
MODIFIED ARCTIC AIR ACROSS THE REGION...THIS WILL BE CHANGING. IN
FACT...THE MORE AMPLIFIED FLOW PATTERN BECOMES MUCH MORE ZONAL
ACROSS THE CENTRAL CONUS MUCH OF THE COMING WEEK AND THESE SAME
TELECONNECTIONS TREND IN THE OPPOSITE DIRECTION. THIS SUGGESTS A
FAIRLY ACTIVE PATTERN BUT WITH LESS COLD AIR THAN THE LAST WEEK OR
SO. INDEED THE TWO MOST IMPACTFUL FEATURES CURRENTLY PROGGED LOOK
TO BE INSIDE RUNNERS THANKS TO EARLIER SHARPENING OF THE
ASSOCIATED TROF ALONG WITH SOME INFLUENCE OF THE SRN STREAM. A
BLEND OF OPERATIONAL GUIDANCE WILL BE USED AS A BASELINE AS THE
TRACK DISCREPANCIES ARE BEGINNING TO CONVERGE FOR THE TUE LOW PRES
PASSAGE.

DETAILS...

MON...
HIGH PRES WILL BE MOVING OVER THE REGION THROUGH THE DAY ON MON.
ALTHOUGH TEMPS WILL START COLD THANKS TO GOOD RADIATIONAL COOLING
SUN NIGHT...MODEST LATE DAY RETURN FLOW WILL ALLOW FOR SOME
WARMING AS H92 TEMPS INCREASE BACK TO NEAR -8C. THIS WILL ALLOW A
BIT OF A REPRIEVE AS HIGHS GO BACK INTO THE 20S TO MID 30S.
HOWEVER...DIURNAL COOLING...ALONG WITH EVAPORATIONAL COOLING IS
EXPECTED AS ISENTROPIC LIFT BEGINS BY LATE AFTERNOON/EVENING.

MON NIGHT INTO TUE NIGHT...
STRENGTHENING BUT NON-OCCLUDING LOW PRES APPROACHES FROM THE
MISSISSIPPI VALLEY...CARRYING WITH IT GULF MOISTURE AND PWATS OF 2
STD DEVIATIONS ABOVE NORMAL...OR GENERALLY ABOVE 1.00 INCHES.
ISENTROPIC LIFT ON THE FRONT END MON NIGHT WILL YIELD EVAPORATIVE
COOLING AND DIURNAL COOLING SUCH THAT PRECIP WILL START IN THE
EVENING AS LIGHT-MOD SN. QPF VALUES DURING THIS PERIOD RANGE FROM
ABOUT 0.1 TO 0.25 INCHES...SO WHERE IT STAYS DEEPLY COLDEST THE
LONGEST /NW MA/...AS MUCH AS 2-3 INCHES OF SNOW /LESS AND LESS
TOWARD THE COAST/ IS POSSIBLE BEFORE WARMER AIR ABOVE 0F MOVES IN
AT H92-H85. THIS WILL BEGIN A TRANSITION TO RAIN FROM S-N AFTER
MIDNIGHT THROUGH ABOUT 7AM. NOT A TRADITIONAL COLD AIR DAMMING
SITUATION HERE AS HIGH PRES IS ORIENTED WELL TO THE
ENE...ALTHOUGH DO NOTE SOME RESPONSE IN THE MASS FIELDS IN THE
FORM OF AN INVERTED RIDGE. THEREFORE...CAN/T RULE OUT SOME ICE
ACCRETION ON THE NEW FRESH SNOWPACK...ESPECIALLY IN THE CT VALLEY
AND COLDER VALLEYS OF THE WORCESTER HILLS AND NRN CT HIGH
TERRAIN. POSSIBLE T-0.2 INCHES OF ICE IS POSSIBLE...SUGGESTING AT
LEAST WINTER WX ADVISORIES ARE LIKELY GOING TO BE NEEDED.

BY TUE...WARM ADVECTION WILL HAVE INCREASED ENOUGH TO BRING SFC
TEMPS ABOVE NORMAL IN SPITE OF THE MODEST SNOWPACK ACROSS THE
REGION. THIS WILL LEAD TO A CHANGEOVER TO ALL RAIN. HEAVY RAIN
LOOKS LIKELY AT TIMES GIVEN THE HIGH PWATS AND INCREASING LLJ WITH
60-70 KT POSSIBLE AS LOW AS H92. QPF VALUES COULD BE GREATER THAN
AN INCH AFTER THE CHANGEOVER GIVEN THE DYNAMICS AND MOISTURE
AVAILABLE...SO WILL NEED TO WATCH FOR MINOR/NUISANCE FLOODING
ESPECIALLY AS SNOWS COULD CLOG AREA DRAINS. OTHER ISSUES IS THE
LLJ ITSELF...WHICH COULD YIELD DANGEROUS STRONG WINDS.
HOWEVER...THE EARLY SNOW AND INCREASE IN TEMPS ALOFT COULD YIELD
ENOUGH OF AN INVERSION TO LIMIT POTENTIAL WIND GUSTS. BUFKIT
CURRENTLY SUPPORTS THIS HYPOTHESIS...KEEPING ANY MOMENTUM TRANSFER
NUMBERS BELOW EVEN ADVISORY CRITERIA. WILL STILL NEED TO WATCH
THIS HOWEVER...GIVEN HOW STRONG THE LLJ IS EXPECTED TO BE /AS MUCH
AS 3 STD DEVIATIONS ABOVE H92 NORMAL/. OVERNIGHT LOWS IN THE 20S
WILL GIVE WAY TO HIGHS MAINLY IN THE UPPER 30S AND 40S...ALTHOUGH
AN ISOLATED 50F CANNOT BE RULED OUT.

WED INTO THU...
SECONDARY ARCTIC FRONT WILL BE SLIDING THROUGH THE REGION
FOLLOWING THE EXITING LOW PRES. WED HIGHS STILL MILD...MAINLY IN
THE UPPER 30S TO UPPER 40S AS THE COLD AIR WILL NOT ARRIVE UNTIL
OVERNIGHT. AN ISOLATED OVERNIGHT SHSN IS POSSIBLE AS THE WAVE
MOVES THROUGH...BUT OVERALL THIS FEATURE IS MOISTURE STARVED SO
ANY ACCUMS WOULD BE LIGHT. HOWEVER THE INCREASED CLOUD COVER WILL
KEEP MINS MAINLY IN THE 20S. BY THU...H92 TEMPS ARE BACK TO NEAR
-10C...SO HIGHS WILL ONLY BE IN THE 20S TO MID 30S AT THE WARMEST
IN SPITE OF THE CLEARING SKIES.

THU NIGHT INTO FRI...
HIGH PRES CRESTS OVER THE REGION...WITH ANOTHER GRADUAL WARMING
TREND AS THE HIGH MOVES E AND H92 TEMPS RETURN TO NEAR -4C. THIS
SUGGESTS HIGHS FRI BACK IN THE 40S ONCE AGAIN.

SAT INTO SUN...
ALTHOUGH FAR FROM A WASHOUT...ALBERTA CLIPPER ASSOCIATED WITH
SHORTWAVE ENERGY CURRENTLY WRAPPED UP IN THE ALLEUTIAN VORTEX WILL
BE CROSSING THE REGION. CURRENT STEERING FLOW SUGGESTS A NORTHWARD
PASSAGE WHICH KEEPS SRN NEW ENGLAND ON THE CLIMATOLOGICALLY DRIER
SIDE OF A CLIPPER. THEREFORE...EXPECT THE MILDER WX TO
CONTINUE...WITH A RISK FOR SHRA FOR A PERIOD ONCE THE TIMING IS
BETTER LOCKED IN. THIS WILL BE LIKELY ONCE THE AFOREMENTIONED
SHORTWAVE MOVES ONSHORE FROM THE PACIFIC.

&&

.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /THROUGH TONIGHT/...

TODAY AND TONIGHT...HIGH CONFIDENCE.  VFR CONDITIONS WITH CLEAR
SKIES.  NORTHWEST WIND GUSTS OF 20 TO 30 KNOTS GRADUALLY DIMINISH
TODAY AND ESPECIALLY BY EARLY THIS EVENING.  THE EXCEPTION TO THE
CLEAR SKIES WILL BE THE OUTER-CAPE/NANTUCKET WHERE OCEAN EFFECT
CLOUDS BETWEEN 2000 TO 3000 FEET WILL PERSIST INTO THE AFTERNOON.
OCEAN EFFECT SNOW SHOWERS WILL ALSO CONTINUE ACROSS THE OUTER-CAPE
THIS MORNING...BEFORE TAPERING OFF THIS AFTERNOON.  THE LIMITED
FETCH WILL RESULT IN LITTLE MORE THAN FLURRIES FROM HYANNIS TO THE
UPPER CAPE.

KBOS TERMINAL...HIGH CONFIDENCE IN TAF.

KBDL TERMINAL...HIGH CONFIDENCE IN TAF.

OUTLOOK /MONDAY THROUGH THURSDAY/...

MON...HIGH CONFIDENCE.
MAINLY VFR THROUGH THE DAY WITH HIGH PRES. WINDS SHIFT TO THE SE.

MON NIGHT INTO TUE NIGHT...MODERATE CONFIDENCE.
PERIODS OF IFR/MVFR DUE TO A COMBINATION OF LOW CIGS AND VSBYS.
PRECIP STARTS AS SNOW MON EVENING...THEN TRANSITIONS TO A BRIEF
PERIOD OF FZRA/SLEET BRIEFLY BEFORE TURNING TO ALL RAIN DURING THE
DAY ON TUE. SE WINDS MAY GUST 20-30 KT AT TIMES DURING THE DAY ON
TUE...BUT VERY STRONG WINDS JUST OFF THE DECK COULD MIX DOWN AT
TIMES. EXPECT LLWS...WITH AS MUCH AS 60-70 KT AT 2KFT.  

WED INTO THU...MODERATE CONFIDENCE.
MAINLY VFR BUT WITH COOLING CONDITIONS LATE WED INTO THU. LOW RISK
FOR AN ISOLATED SHSN WED NIGHT.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /THROUGH TONIGHT/...HIGH CONFIDENCE. 

***HEAVY FREEZING SPRAY/ARCTIC SEA SMOKE AND GALE FORCE WIND GUSTS
  PERSISTS INTO MID/LATE MORNING BEFORE DIMINISHING***

TODAY...INCREDIBLE ARCTIC OUTBREAK FOR THE MODERN ERA WILL RESULT IN
AREAS OF HEAVY FREEZING SPRAY AND GALE FORCE WIND GUSTS THIS
MORNING. IN ADDITION...ARCTIC SEA SMOKE WILL OCCUR WITH LARGE AIR TO
SST DIFFERENTIAL. WINDS SHOULD GRADUALLY BEGIN TO SLACKEN LATER THIS
MORNING AND EARLY AFTERNOON...DROPPING TO SMALL CRAFT LEVELS. STILL
MAY HAVE POCKETS OF MODERATE FREEZING SPRAY PERSIST INTO THE
AFTERNOON ACROSS OUR EASTERN MA WATERS. 

TONIGHT....LINGERING SMALL CRAFT SEAS/WIND GUSTS AND MODERATE
FREEZING SPRAY ACROSS OUR EASTERN WATERS SHOULD DIMINISH BELOW
CRITERIA AFTER MIDNIGHT. OTHERWISE...WINDS/SEAS BELOW SCA THRESHOLDS
THE REST OF THE NIGHT AS LARGE HIGH PRESSURE BUILDS ACROSS THE
REGION.

SUNDAY INTO SUNDAY NIGHT...HIGH CONFIDENCE.

NW-WINDS TAPERING ALONG WITH SEAS. GALES CONCLUDING...SMALL CRAFT
HEADLINES WILL LIKELY HOLD FOR A MAJORITY OF THE FORECAST PERIOD.
HIGH PRESSURE BUILDING ACROSS THE WATERS. 

OUTLOOK /MONDAY THROUGH THURSDAY/...

MON...HIGH CONFIDENCE.
QUIET BOATING WEATHER WITH HIGH PRES OVER THE WATERS.

MON NIGHT INTO TUE NIGHT...MODERATE CONFIDENCE.
LOW PRES WILL APPROACH FROM THE SW...THEN MOVE INLAND DURING THE
DAY TUE. INCREASE SE WINDS WILL LEAD TO GUSTS 25-30 KT MON
NIGHT...THEN SHIFTING LATE TUE NIGHT. SEAS BUILD DURING THIS TIME
AS WELL...AND COULD REACH 10-13 FT BY TUE EVENING. SMALL CRAFT
ADVISORIES WILL BE NEEDED. THERE IS A LOW RISK FOR GALES...BUT IT
IS UNCERTAIN AT THIS TIME.

WED AND WED NIGHT...HIGH CONFIDENCE.
WINDS SHIFT TO THE W...BUT DROP BELOW 25 KT. SEAS WILL BEGIN TO
SUBSIDE...BUT WILL TAKE SOME TIME. SO SMALL CRAFT ADVISORIES ARE
LIKELY TO CONTINUE THROUGH MUCH OF THE DAY FOR SEAS ALONE. 

THU...HIGH CONFIDENCE.
ALTHOUGH WIND GUSTS SHOULD REMAIN BELOW THRESHOLD AS WINDS SHIFT
TO THE NW AND PERSIST...THERE COULD BE 5-7 FT SEAS PERSISTING ON
THE OCEAN WATERS.

&&

.CLIMATE...

***COLDEST TEMPERATURES RECORDED IN BOSTON/WORCESTER SINCE 1957***

BOSTON SET A NEW RECORD LOW OF -4 JUST BEFORE MIDNIGHT ON FEBRUARY
13TH.  THROUGH 4 AM THIS MORNING...TEMP IS DOWN TO -9 WHICH ALSO
ESTABLISHES A NEW RECORD FOR TODAY.  THIS IS THE FIRST TIME BOSTON
HAS SET A RECORD LOW IN THE MONTH OF FEBRUARY SINCE 1967.  ITS ALSO
THE COLDEST TEMPERATURE AT BOSTON SINCE 1957!

THROUGH 4 AM THIS MORNING...WORCESTER HAS DROPPED TO -15 BREAKING
THEIR OLD RECORD LOW OF -11 SET IN 1979.  ITS ALSO THE COLDEST
TEMPERATURES IN WORCESTER SINCE 1957!

THROUGH 4 AM THIS MORNING...HARTFORD HAS DROPPED TO -10 WHICH
BREAKS THEIR OLD RECORD LOW -9 IN 1979.  

THROUGH 4 AM THIS MORNING...PROVIDENCE HAS DROPPED TO -8 WHICH
BREAKS THEIR OLD RECORD OF LOW OF -7 IN 1979.

RECORD COLD HIGHS FOR FEB 13TH - 14TH...

BOSTON.......15/1979 - 14/1916 
HARTFORD.....11/1979 - 11/1979
PROVIDENCE...10/1979 - 10/1979
WORCESTER.... 8/1899 -  7/1979
BLUE HILL.... 9/1899 - 10/1979

RECORD COLD LOWS FOR FEB 13TH - 14TH - 15TH...

BOSTON...... -3/1967 -  -3/1934 - -14/1943
HARTFORD.... -7/1967 -  -9/1979 - -18/1943
PROVIDENCE.. -5/1967 -  -7/1979 - -14/1943
WORCESTER...-12/1967 - -11/1979 - -19/1943
BLUE HILL...-10/1967 - -9/1979 - -18/1943

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...WIND CHILL WARNING UNTIL NOON EST TODAY FOR CTZ002>004.
MA...WIND CHILL ADVISORY UNTIL NOON EST TODAY FOR MAZ022>024.
     WIND CHILL WARNING UNTIL NOON EST TODAY FOR MAZ002>021-026.
RI...WIND CHILL ADVISORY UNTIL NOON EST TODAY FOR RIZ008.
     WIND CHILL WARNING UNTIL NOON EST TODAY FOR RIZ001>007.
MARINE...HEAVY FREEZING SPRAY WARNING UNTIL 11 AM EST THIS MORNING FOR 
     ANZ231>235-237-250-251-254>256.
     GALE WARNING UNTIL 10 AM EST THIS MORNING FOR ANZ231>235-237-
     251-255-256.
     SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR ANZ230-
     236.
     GALE WARNING UNTIL 2 PM EST THIS AFTERNOON FOR ANZ250-254.

&&

$$
SYNOPSIS...FRANK/DOODY
NEAR TERM...FRANK
SHORT TERM...FRANK
LONG TERM...DOODY
AVIATION...FRANK/DOODY
MARINE...FRANK/DOODY
CLIMATE...FRANK

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