Area Forecast Discussion
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000
FXUS61 KBOX 311528
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
1028 AM EST SAT JAN 31 2015

.SYNOPSIS...
BLUSTERY AND VERY COLD CONDITIONS CONTINUE THROUGH THE WEEKEND. A
MAJOR WINTER STORM WILL AFFECT THE REGION SUNDAY NIGHT INTO
MONDAY EVENING WITH POTENTIALLY HEAVY SNOW ACCUMULATION AND GUSTY
WINDS. A FRIGID AIRMASS WILL FOLLOW MONDAY NIGHT WITH DANGEROUSLY
COLD WIND CHILLS. MODERATING TEMPS WEDNESDAY THEN VERY COLD
CONDITIONS WILL RETURN TOWARD THE END OF THE WEEK. A COASTAL STORM
WILL PASS WELL SOUTH OF NEW ENGLAND LATE IN THE WEEK BUT WILL
HAVE TO BE MONITORED.

&&

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

1030 AM UPDATE...

SNOW WILL LINGER ACROSS THE CAPE FOR THE NEXT HOUR OR TWO BUT WILL
MOVE OFFSHORE. SNOW RANGES ARE GENERALLY 1-2 INCHES ACROSS THE
IMMEDIATE EAST COAST PER REPORTS. 700 MB LOW HAS CUTOFF THIS
MORNING ALLOWING FOR PRESSURE GRADIENT TO INCREASE AND GUSTY WINDS
WILL CONTINUE. WIND GUSTS AROUND 20-40 MPH WILL INCREASE THE
POTENTIAL FOR BLOWING AND DRIFTING SNOW SO HAVE INSERTED THE
POTENTIAL INTO THE FORECAST.

TEMPERATURES ARE STARTING TO INCREASE ACROSS THE REGION SO HAVE
DROPPED MOST OF THE WIND CHILL ADV. DID KEEP ON IMMEDIATE WESTERN
ZONES AND ALL OF FRANKLIN COUNTY AS THEY ARE STILL FILTERING WITH
-15F AS OF 10 AM. PLAN IS STILL TO LET THE ADVISORY DROP AT 11AM.

ASIDE FROM MINOR CHANGES...BULK OF THE FORECAST REMAINS ON TRACK
FOR TODAY.

PREVIOUS DISCUSSION...

STRONG NW WINDS WILL CONTINUE TODAY. GUSTS 35-45 MPH EXPECTED WITH
A FEW GUSTS NEAR 50 MPH NEAR THE COAST.

BITTER COLD WIND CHILLS DOWN TO -10 TO -20 THIS MORNING ACROSS
CENTRAL AND W NEW ENG AND -5 TO -10 IN THE COASTAL PLAIN.
AFTERNOON HIGH TEMPS ONLY IN THE TEENS MOST LOCATIONS BUT WITH THE
STRONG WINDS...WIND CHILLS WILL ONLY RECOVER TO -5 TO +5.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
TONIGHT...

WEAK SFC RIDGE MOVES INTO THE REGION AHEAD OF ARCTIC FRONT
DROPPING INTO N NEW ENG. THIS WILL RESULT IN GRADUAL DIMINISHING
WINDS TONIGHT...BUT REMAINING RATHER GUSTY OVER THE CAPE/ISLANDS
THROUGH THE NIGHT. MIN TEMPS WILL DROP INTO THE SINGLE NUMBERS
WITH TEENS ALONG THE IMMEDIATE COAST AND CAPE/ISLANDS.

SUNDAY...

ARCTIC FRONT WILL PUSH S INTO SNE REACHING THE S COAST BY EVENING.
SUNSHINE WILL GIVE WAY TO INCREASING CLOUDS IN THE AFTERNOON AS
OVERRUNNING MID/HIGH CLOUDS MOVE INTO THE REGION...ALONG WITH
DEVELOPMENT OF SOME LOWER CLOUDS AS LOW LEVEL MOISTURE INCREASES.
BUT REMAINING DRY THROUGH THE DAY. HIGH TEMPS MOSTLY IN THE
MID/UPPER 20S BUT DROPPING BACK INTO THE TEENS TOWARD EVENING
ACROSS N ZONES AS ARCTIC AIR BEGINS TO DRAIN SOUTH.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
HIGHLIGHTS...

* LOW PRES PASSES S OF NEW ENGLAND SUN NIGHT AND MON...COLD AIR IN
  PLACE SIGNALS PLOWABLE SNOWFALL FOR THE REGION
* WINTER STORM WATCH EXTENDED TO COVER ENTIRE REGION
* AS LOW EXITS MON NIGHT...MORE ARCTIC AIR AND STRONG WINDS MOVE
  IN...WIND CHILL HEADLINES LIKELY
* RECORD LOWS POSSIBLE TUESDAY MORNING WITH HIGH PRES
* ANOTHER LOW POSSIBLE WED OR THU...LOW CONFIDENCE CONTINUES

OVERVIEW...

MODELS AND ENSEMBLES CONTINUE TO SIGNAL PROGRESSIVE PATTERN BUT
GENERAL LONG WAVE TROUGHING ACROSS THE EASTERN U.S. THROUGH MOST OF
THE LONG TERM PERIOD. SEVERAL H5 SHORT WAVES IN NORTHERN STREAM FLOW
DURING THIS TIMEFRAME. VERY COLD AIR WILL REMAIN ACROSS THE REGION
THROUGH TUESDAY...THEN TEMPS WILL RISE CLOSER TO SEASONAL NORMALS
AROUND MID WEEK. ANOTHER ARCTIC FRONT AND POSSIBLE LOW PRESSURE MAY
BRING ANOTHER ROUND OF WINTRY PRECIPITATION AROUND WED OR THU.

DETAILS...

SUNDAY NIGHT THROUGH MONDAY NIGHT...
VIGOROUS H5 SHORT WAVE AND ASSOCIATED SURFACE LOW PRES MOVE OUT
OF THE OHIO VALLEY TO THE MID ATLC COAST BY 12Z MON. BY THEN...
THOUGH...EXCELLENT OVERRUNNING IN PLACE WITH DEEP MOISTURE FEED
WORKING INTO THE REGION. WITH COLD AIR ALREADY IN PLACE...AND HIGH
PRES MOVING IN TANDEM ACROSS SOUTHERN CANADA... WILL NOT BE
DISPLACED. EXPECT LIGHT SNOW TO SPREAD ACROSS THE REGION SUNDAY
NIGHT.

AS THE LOW MOVES OFF THE MID ATLC COAST...WILL SEE STRONG
INTENSIFICATION OF THE SYSTEM AS IT MOVES ALONG 40N LATITUDE
BEFORE TURNING NE NEAR THE 40N/70W BENCHMARK MON EVENING.
EXCELLENT DENDRITIC GROWTH WITH ARCTIC AIRMASS...SO EXPECT PERIODS
OF MODERATE TO HEAVY SNOWFALL ESPECIALLY MONDAY MORNING THROUGH
MIDDAY AS THE LOW PASSES TO THE S. LOOKS LIKE THE HEAVIEST
SNOWFALL WILL OCCUR S OF THE MASS PIKE...BUT THE ENTIRE REGION
WILL SEE A GOOD AMOUNT OF SNOWFALL. ONLY QUESTION AT THIS POINT
WILL BE WHETHER A PIECE OF SOMEWHAT MILDER AIR ALOFT WILL WORK
INTO THE OUTER CAPE AND ISLANDS WHICH COULD CAUSE A BRIEF MIX WITH
SLEET OR EVEN RAIN MON MORNING OR MIDDAY. ONCE THE LOW
PASSES...THOUGH...WILL CHANGE QUICKLY BACK TO SNOW THERE DURING
THE AFTERNOON.

WITH THE SNOW ARRIVING SUNDAY NIGHT...CAN EXPECT AT LEAST LIGHT
SNOW ACCUMULATIONS BY THE TIME OF THE START OF THE MONDAY MORNING
COMMUTE. EXPECT A ROUGH COMMUTE IF ANYONE EVEN VENTURES OUT OF
DOORS MONDAY MORNING. VSBYS WILL ALSO BE REDUCED AS WELL.

WITH ALL MODELS IN VERY GOOD AGREEMENT...AND QPF TOTALS ON ORDER
OF 0.6 TO 1.1 INCHES FROM N-S ACROSS THE REGION AND COLD AIRMASS
IN PLACE...WILL SEE SNOW TO LIQUID RATIOS AROUND 13:1 OR SO PRETTY
MUCH EVERYWHERE EXCEPT AROUND 10:1 ON THE OUTER CAPE AND THE
ISLANDS. WITH THIS IN MIND...HAVE UPDATED THE WINTER STORM WATCH
TO INCLUDE THE ENTIRE REGION...ADDING NORTHERN MASSACHUSETTS AND
THE ISLANDS TO THE WATCH.

THE LOW WILL INTENSIFY RAPIDLY AS IT EXITS LATE MON AND MON NIGHT.
INCREASING PRES GRADIENT WILL CAUSE N-NW WINDS TO INCREASE...WITH
GUSTS UP TO 30-40 MPH OR HIGHER ESPECIALLY ALONG THE E COAST.

AS FOR COASTAL FLOODING...IT APPEARS THAT THE STRONGER N-NE WINDS
WILL OCCUR AROUND THE TIME OF LOW TIDE MONDAY AFTERNOON. COULD SEE
UP SURGE TO ONE OR TWO FEET. THE SURGE IS NOT COINCIDING WITH
HIGH TIDE...SO WE DO NOT EXPECT ISSUES AT THIS TIME. WILL
CONTINUE TO MONITOR THIS ASPECT CLOSELY THOUGH.

TEMPERATURES MONDAY NIGHT WILL PLUMMET AS ANOTHER SHOT OF ARCTIC
AIR WORKS IN. EXPECT OVERNIGHT LOWS TO COME CLOSE TO RECORD LOWS
DURING THE PRE-DAWN HOURS OF TUE MORNING. MAINLY LOCATIONS WILL
LIKELY SEE READINGS BELOW ZERO...EXCEPT ALONG THE IMMEDIATE S
COAST...CAPE COD AND THE ISLANDS. PLEASE SEE THE CLIMATE SECTION
BELOW FOR THE RECORDS.

TUESDAY...
HIGH PRES RIDGE BUILDS ACROSS. WILL SEE BLUSTERY CONDITIONS EARLY
TUE...BUT COLD AIR REMAINS IN PLACE. EXPECT HIGHS ONLY IN THE
TEENS...RANGING TO AROUND 20 ALONG THE IMMEDIATE S COAST.

WEDNESDAY-THURSDAY...
THE HIGH PUSHES OFFSHORE ON WED...WITH A RETURN FLOW OF MILDER
AIR. TEMPS WED INTO THU MAY ACTUALLY REBOUND CLOSE TO SEASONAL
NORMALS WITH LIGHT SW WINDS.

BIG QUESTION AT THIS POINT WILL BE THE APPROACH OF A COLD FRONT
OUT OF CENTRAL CANADA ALONG WITH THE DEVELOPMENT OF LOW PRES. NOT
A LOT OF CONFIDENCE AT THIS POINT DUE TO WIDE MODEL VARIANCE. FOR
NOW...HAVE MENTIONED CHANCE OF PRECIP...MAINLY LIGHT SNOW...AS
COLD FRONT PASSES AROUND WED NIGHT OR EARLY THU.

FRIDAY...
ANOTHER HIGH LOOKS TO BUILD E WITH MORE COLD AIR...BUT TIMING IS
UNCERTAIN.

&&

.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM.../THROUGH SUNDAY/...HIGH CONFIDENCE.

TODAY...EXPECT VFR WITH CLEARING SKIES. NW GUSTS TO 30-40 KT. A
FEW SNOW SHOWERS ALONG THE OUTER CAPE BUT CIGS SHOULD BE VFR.

TONIGHT...VFR WITH GRADUAL DIMINISHING WIND.

SUNDAY...MAINLY VFR...BUT LOW PROB FOR AREAS OF MVFR CIGS
DEVELOPING IN THE AFTERNOON.

KBOS TAF...HIGH CONFIDENCE. MVFR VSBYS DUE TO LIGHT SNOW AND
BLOWING SNOW EARLY THIS MORNING. IMPROVING CONDITIONS AFT 12Z.

KBDL TAF...HIGH CONFIDENCE.

OUTLOOK /SUNDAY NIGHT THROUGH WEDNESDAY/...

SUNDAY NIGHT INTO MONDAY NIGHT...MODERATE CONFIDENCE.

VFR TO START...THEN QUICKLY DETERIORATING CONDITIONS TO IFR-
VLIFR WITH SNOW MOVING IN FROM W-E. PERIODS OF HEAVY SNOW POSSIBLE
MONDAY MORNING INTO MIDDAY. BLUSTERY NE WINDS WITH GUSTS UP TO
AROUND 30 KT STARTING MON AFTERNOON THEN VEER TO NW BUT REMAIN
GUSTY MON NIGHT. CONDITIONS IMPROVE FROM W-E MON NIGHT...BUT LOWER
CIGS/VSBYS MAY LINGER ALONG E COAST THROUGH MOST OF THE NIGHT

TUESDAY...MODERATE CONFIDENCE. MAINLY VFR. NW WIND GUSTING TO 25-30
KT EARLY THEN SHOULD DIMINISH.

WEDNESDAY...MODERATE CONFIDENCE. VFR THROUGH MIDDAY. MAY SEE MVFR
CONDITIONS MOVE INTO N MA DURING THE AFTERNOON IN SNOW SHOWERS.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /THROUGH SATURDAY NIGHT/...HIGH CONFIDENCE.

1030 AM UPDATE...HAVE EXPANDED THE FREEZING RAIN ADV FOR THE
SOUTHERN OUTER WATERS. BUOY 44008 IS REPORTING FREEZING SPRAY SO
EXPECT IT TO BE OCCURRING ACROSS THE NEW ADVISORY REGION.

TODAY...GALE CENTER LIFTS INTO THE MARITIMES WITH NW GALES
CONTINUING OVER THE WATERS. GUSTS TO 40-45 KT LIKELY WITH
MODERATE FREEZING SPRAY LIKELY. SNOW SHOWERS REDUCE VSBY OVER
EASTERN MA WATERS IN THE MORNING.

TONIGHT...GALE CENTER PULLS FARTHER AWAY WITH WINDS DIMINISHING
BELOW GALE 00-06Z...BUT GUSTS 25-30 KT WILL CONTINUE OVERNIGHT.
MODERATE FREEZING SPRAY LIKELY CONTINUING...ESPECIALLY E MA
COASTAL WATERS.

SUNDAY...WINDS AND SEAS GRADUALLY DIMINISH THROUGH THE DAY. SUB
SCA CONDITIONS DEVELOP OVER THE S COASTAL WATERS DURING THE
MORNING...BUT SCA CONDITIONS WILL CONTINUE ACROSS THE OUTER
EASTERN WATERS. LIGHT FREEZING SPRAY WILL PERSIST.

OUTLOOK /SUNDAY NIGHT THROUGH WEDNESDAY/...

SUNDAY NIGHT...MODERATE CONFIDENCE.
WINDS BACK FROM NW TO N DURING THE NIGHT...GUSTS INCREASING TO
AROUND 20 KT ON THE SOUTHERN OUTER WATERS. VSBYS LOWER IN
DEVELOPING LIGHT SNOW FROM W-E.

MONDAY AND MONDAY NIGHT...MODERATE CONFIDENCE.
EXPECT INCREASING E-NE WINDS...GUSTING UP TO 35-40 KT LATE MONDAY
AND MONDAY NIGHT. SEAS BUILDING AS HIGH AS 14-17 FT ON THE EASTERN
WATERS AS LOW PRES INTENSIFIES AS IT PASSES S OF THE SOUTHERN
WATERS. WINDS SHIFT TO NW BUT REMAIN GUSTY MON NIGHT. REDUCED
VSBYS IN SNOW...FALLING HEAVILY AT TIMES.

TUESDAY...MODERATE CONFIDENCE.
NW WINDS CONTINUE TO GUST CLOSE TO GALE FORCE THROUGH THE MORNING
THEN WILL DIMINISH BUT REMAIN AT SMALL CRAFT CRITERIA. SEAS REMAIN
HIGH...UP TO 8-10 FT BUT WILL SLOWLY SUBSIDE. WINDS MAY DIMINISH
BELOW SMALL CRAFT TUE NIGHT...BUT SEAS MAY LINGER AROUND 5 FT.

WEDNESDAY....MODERATE CONFIDENCE.
WINDS BACK TO SW AND INCREASE...MAY SEE GUSTS UP TO 25-30 KT.
SEAS ALSO REMAIN AROUND 5 FT...MAINLY OVER THE OUTER WATERS.

&&

.CLIMATE...
WITH EXTREMELY COLD AIR MOVING IN BEHIND THE DEPARTING LOW MONDAY
NIGHT...TEMPERATURES MAY FALL BACK CLOSE TO OR SURPASSING RECORD
LEVELS EARLY TUESDAY MORNING. AND THAT IS NOT TAKING INTO ACCOUNT
THE STRONG WINDS.

HERE ARE THE RECORD LOWS FOR TUESDAY 2/3...

BOSTON         -5 SET IN 1881
PROVIDENCE     -6 SET IN 1961
WORCESTER      -7 SET IN 1931, 1955 AND 1971
WINDSOR LOCKS  -3 SET IN 1955
BLUE HILL OBS  -7 SET IN 1955

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...WINTER STORM WATCH FROM SUNDAY EVENING THROUGH LATE MONDAY
     NIGHT FOR CTZ002>004.
MA...WIND ADVISORY UNTIL 9 PM EST THIS EVENING FOR MAZ022>024.
     WINTER STORM WATCH FROM SUNDAY EVENING THROUGH LATE MONDAY
     NIGHT FOR MAZ002>024-026.
     WIND ADVISORY UNTIL 6 PM EST THIS EVENING FOR MAZ007-015-016-
     019>021.
     WIND CHILL ADVISORY UNTIL 11 AM EST THIS MORNING FOR MAZ002-
     003-008-009.
RI...WIND ADVISORY UNTIL 9 PM EST THIS EVENING FOR RIZ008.
     WINTER STORM WATCH FROM SUNDAY EVENING THROUGH LATE MONDAY
     NIGHT FOR RIZ001>008.
     WIND ADVISORY UNTIL 6 PM EST THIS EVENING FOR RIZ005>007.
MARINE...FREEZING SPRAY ADVISORY UNTIL 6 AM EST SUNDAY FOR ANZ231-232-
     250-251.
     GALE WARNING UNTIL 1 AM EST SUNDAY FOR ANZ231-232-250-251-
     254>256.
     FREEZING SPRAY ADVISORY UNTIL 6 PM EST THIS EVENING FOR
     ANZ233>235-237.
     GALE WARNING UNTIL 10 PM EST THIS EVENING FOR ANZ233>235-237.
     GALE WARNING UNTIL 9 PM EST THIS EVENING FOR ANZ230.
     GALE WARNING UNTIL 6 PM EST THIS EVENING FOR ANZ236.
     FREEZING SPRAY ADVISORY UNTIL 8 PM EST THIS EVENING FOR
     ANZ254>256.

&&

$$
SYNOPSIS...KJC
NEAR TERM...KJC/DUNTEN
SHORT TERM...KJC
LONG TERM...EVT
AVIATION...KJC/EVT/DUNTEN
MARINE...KJC/EVT/DUNTEN
CLIMATE...STAFF


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