Area Forecast Discussion
Issued by NWS Boston, MA

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000
FXUS61 KBOX 030317
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
1017 PM EST TUE FEB 2 2016

.SYNOPSIS...
CANADIAN HIGH PRESSURE WILL BUILD INTO THE REGION THROUGH TONIGHT.
A DEEPENING AREA OF LOW PRESSURE WILL TRACK NORTHEAST ACROSS THE
GREAT LAKES WED AND UP INTO EASTERN CANADA WED NIGHT...SENDING A
SLOW MOVING COLD FRONT ACROSS THE REGION. EXPECT WIDESPREAD RAIN
WITH EMBEDDED HEAVIER SHOWERS AND POSSIBLY A RUMBLE OF THUNDER ON
WEDNESDAY AHEAD OF THIS COLD FRONT. THE FRONT WILL STALL JUST OFF
THE COAST THU AS ANOTHER WAVE OF LOW PRES TRACKS TO THE EAST OF NEW
ENG THU NIGHT INTO FRI. HIGH PRESSURE BRINGS MAINLY DRY CONDITIONS
THIS WEEKEND...THEN A COASTAL STORM MAY AFFECT THE REGION EARLY NEXT
WEEK.

&&

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

1030 PM UPDATE...

NO MAJOR CHANGES TO THE FORECAST AT THIS TIME. TRIED TO LINE UP
TEMPS TOWARDS CURRENT TRENDS. MANY SITES HAVE RADIATED OUT WITH
MVY DOWN TO 26 AND OWD/TAN DOWN IN THE MID 20S. HIGH LEVEL CLOUDS
ARE ALREADY MOVING INTO THE AREA LIMITING COOLING POTENTIAL AND
WITH A SOUTHERLY BREEZE BEGIN TO DEVELOP...TEMPS MAY STALL OR
BEGIN TO RISE AFTER MIDNIGHT.

WILL CONTINUE TO MONITOR TRENDS FOR THE POTENTIAL FOR FREEZING
RAIN TOMORROW MORNING. RIGHT NOW ONLY THE HRRR AND RAP SHOW PRECIP
MOVING IN AROUND THE 7AM HOUR. WILL WAIT UNTIL THE 00Z HI-RES
GUIDANCE TO GET A BETTER PICTURE.

PREVIOUS DISCUSSION... HIGH PRES OVERHEAD WITH CLEAR SKIES AND
LIGHT WINDS WILL ALLOW TEMPS TO FALL SHARPLY THIS EVENING BEFORE
STABILIZING OR RISING SLOWLY OVERNIGHT AS CLOUDS MOVE IN AND
SOUTHERLY BREEZE DEVELOPS. UPDATED T/TD GRIDS FOR CURRENT
OBS/TRENDS. MIN TEMPS MID 20S TO LOWER 30S.

MAIN CONCERN TOWARD DAYBREAK IS THE POTENTIAL FOR SOME LIGHT
FREEZING RAIN ACROSS E SLOPES OF BERKSHIRES AND NORTHERN WORCESTER
COUNTY IF PRECIP MOVES IN BY THEN. LATEST HI-RES GUIDANCE KEEP
PRECIP TO THE WEST THROUGH 12Z WHICH WILL LIMIT THE THREAT BUT
SOMETHING TO MONITOR OVERNIGHT.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
WEDNESDAY INTO WEDNESDAY NIGHT...

LOW PRESSURE SYSTEM MOVING THROUGH THE GREAT LAKES INTO SOUTHERN
CANADA WILL BRING A WARM FRONT THROUGH SOUTHERN NEW ENGLAND
WEDNESDAY MORNING AND A COLD FRONT THROUGH LATE WEDNESDAY NIGHT.
OVERALL...THE GUIDANCE IS IN GOOD AGREEMENT WITH THIS STORM...WITH
THE EXCEPTION OF SOME MINOR TIMING DIFFERENCES IN THE ONSET OF
PRECIPITATION.

PRECIPITATION...MAINLY IN THE FORM OF RAIN...WILL OVERSPREAD
SOUTHERN NEW ENGLAND BY WEDNESDAY MORNING.  DEPENDING UPON THE EXACT
TIMING OF ONSET...THERE MAY BE SOME LIGHT FREEZING RAIN IN THE
COLDER VALLEYS ALONG THE EAST SLOPES OF THE BERKSHIRES AND NORTHERN
WORCESTER COUNTY.  SEE NEAR TERM SECTION FOR MORE ON THIS POTENTIAL.
ANY FREEZING RAIN SHOULD CHANGEOVER TO RAIN QUICKLY AS SOUTHERLY
WINDS BRING IN MUCH WARMER TEMPERATURES.  EXPECTING 1 TO 1.5 INCHES
OF RAIN WITH THIS SYSTEM WITH ANOMALOUSLY HIGH PWATS AND A STRONG
LOW LEVEL JET.  MOST OF THIS PERIOD WILL BE WET FOR MOST AREAS.
EXPECT PRECIP TO START TO COME TO AN END ACROSS THE WESTERN ZONES
SOMETIME AFTER MIDNIGHT THURSDAY MORNING.

THUNDER...HAVE INCLUDED A MENTION OF ISOLATED THUNDER FOR AREAS
ALONG THE SOUTH COAST WEDNESDAY EVENING INTO WEDNESDAY NIGHT. MODELS
INDICATE SOME MODEST ELEVATED INSTABILITY.

WINDS...THERE IS A STRONG SOUTHERLY LOW LEVEL JET MOVING OVER
SOUTHERN NEW ENGLAND WITH THIS STORM.  WINDS 1-2KFT OFF THE SURFACE
WILL BE 50 TO 60 KTS.  HOWEVER...SOUNDINGS INDICATE A DECENT
INVERSION IN PLACE THAT WILL LIMIT THESE STRONGER GUSTS FROM
REACHING THE SURFACE.  FOR THE MOST PART...EXPECTING WINDS TO GUST
UP TO ABOUT 35 MPH WITH THE STRONGEST WINDS ON THE CAPE AND ISLANDS.
HOWEVER...IF SHOWERS OR ANY ISOLATED THUNDERSTORMS ARE ABLE TO TAP
INTO THE STRONGER WINDS ALOFT...WE MAY SEE A FEW HIGHER GUSTS IN AND
AROUND THOSE STORMS.

TEMPERATURES...QUITE MILD AS THE SOUTHERLY WINDS BRING WARMER AIR
INTO THE REGION.  HIGH TEMPERATURES WILL BE IN THE 50S ACROSS THE
REGION...DESPITE THE RAIN AND CLOUDS.  THE WARMEST TEMPERATURES WILL
ACTUALLY BE DURING THE EVENING HOURS JUST PRIOR TO THE COLD FRONT
MOVING THROUGH.  TEMPERATURES WILL REMAIN ELEVATED OVERNIGHT WITH
LOW TEMPERATURES ONLY DROPPING INTO THE 40S.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
HIGHLIGHTS...

* LINGERING RAIN SHOWERS POSSIBLE SE NEW ENG THU
* ANOTHER PERIOD OF RAIN POSSIBLE THU NIGHT SE NEW ENG CHANGING TO
  SNOW IF PRECIP MAKES IT FAR ENOUGH WEST INTO NEW ENG
* DRY CONDITIONS THIS WEEKEND
* A COASTAL STORM MAY AFFECT THE REGION SOMETIME EARLY NEXT WEEK BUT
  CONFIDENCE IS LOW

THURSDAY...
LONGWAVE TROF BACK ACROSS CENTRAL US WITH SW FLOW ALOFT ACROSS NEW
ENG. COLD FRONT WILL SLOW ITS EASTWARD PROGRESS AND LIKELY STALL OFF
THE SE NEW ENG COAST WHICH WILL CONTINUE THREAT OF SHOWERS IN THE
COASTAL PLAIN AND ESPECIALLY CAPE/ISLANDS AS DEEP MOISTURE AXIS
REMAINS NEAR THE COAST. OTHERWISE...MODELS SHOW EXCELLENT MID LEVEL
DRYING MOVING INTO W NEW ENG WHICH SHOULD ALLOW FOR AT LEAST PTSUNNY
SKIES FURTHER WEST IN THE INTERIOR. TEMPS STARTING OUT RATHER
MILD...ESPECIALLY SE NEW ENG WHERE HIGH TEMPS WILL BE IN THE
50S...BUT THERE IS A FAIRLY SHARP LOW LEVEL TEMP GRADIENT ACROSS SNE
SO EXPECT 40S FURTHER BACK IN THE INTERIOR.

THURSDAY NIGHT AND FRIDAY...
SHARP MID LEVEL TROF APPROACHES FROM THE WEST WITH FAIRLY ROBUST
SHORTWAVE LEADING TO A WAVE DEVELOPING ON THE OFFSHORE FRONT THU
NIGHT. THE QUESTION BECOMES TO WHAT EXTENT WILL THIS BACK DEEP
MOISTURE PLUME INTO NEW ENG. ECMWF AND GGEM BRING PRECIP BACK WEST
OF THE I95 CORRIDOR WITH ECMWF A BIT SLOWER AND LINGERING PRECIP
INTO FRI...AND BRINGING ACCUMULATING SNOW TO SE NEW ENG AS THE
COLUMN COOLS. GFS FURTHER EAST AND CONFINE PRECIP TO CAPE/ISLANDS.
WE USED A BLEND OF GEFS AND ECMWF EPS WHICH REPRESENTS SOMEWHAT OF A
COMPROMISE. WE WILL INCREASE POPS THU NIGHT ACROSS SE NEW ENG
BRINGING CHC TO SE MA AND RI WITH LIKELY FOR CAPE/ISLANDS. THE
COLUMN IS COOLING FROM THE WEST DURING THU NIGHT SO ANY SHOWERS
WOULD CHANGE TO A PERIOD OF SNOW IF THE PRECIP MAKES IT FAR ENOUGH
WEST. THERE IS A LOW PROB FOR SOME MINOR ACCUM FAR SE MA AND CAPE
COD BUT CONFIDENCE IS LOW AND WILL DEPEND ON PRECIP MAKING IT BACK
ACROSS THE REGION. SOMETHING THAT WILL NEED TO BE MONITORED CLOSELY
IN SUBSEQUENT FORECASTS. TREND WILL BE FOR IMPROVING CONDITIONS
FRI...ALTHOUGH TIMING IS NOT CERTAIN AND SNOW SHOWERS COULD LINGER
INTO FRI MORNING IF TIMING IS SLOWER.

SATURDAY AND SUNDAY...
LOOKS MAINLY DRY DURING THIS WEEKEND. HIGH PRES IN CONTROL TO THE
SOUTH OF NEW ENG SAT...THEN NORTHERN STREAM SHORTWAVE BRINGS A COLD
FRONT INTO NEW ENG SUNDAY...BUT IT IS EXPECTED TO REMAIN DRY.

MONDAY AND TUESDAY...
COMPLEX PATTERN DEVELOPING AS AMPLIFYING NORTHERN STREAM TROF MOVES
ACROSS THE GT LAKES WHILE PACIFIC SHORTWAVE IN THE SOUTHERN STREAM
LIFTS NE OFF THE EASTERN SEABOARD. GFS AND ECMWF SHOW LARGE OCEAN
STORM TRACKING WELL TO THE S OF NEW ENG. MOST OF THE GEFS AND ECMWF
EPS MEMBERS ARE ALSO WELL OFFSHORE BUT THIS IS DAY 6 AND HOW THIS
PACIFIC SHORTWAVE INTERACTS WITH NORTHERN STREAM TROF IS UNCERTAIN SO
THIS WILL HAVE TO BE WATCHED. WILL ALSO NEED TO WATCH FOR POSSIBLE
SECONDARY SHORTWAVE ROTATING AROUND NORTHERN STREAM TROF PER ECMWF
SOLUTION WHICH SPINS UP ANOTHER SIGNIFICANT COASTAL LOW S OF NEW ENG
NEXT TUE. OBVIOUSLY A LOW CONFIDENCE FORECAST AT THIS TIME RANGE BUT
THERE IS POTENTIAL FOR WINTER WEATHER EARLY NEXT WEEK.

&&

.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /THROUGH WEDNESDAY NIGHT/...

THROUGH TONIGHT...HIGH CONFIDENCE. VFR. INCREASING CLOUDS FROM
WEST TO EAST TONIGHT.CLOUDS WILL BE ON THE INCREASE TONIGHT.

WEDNESDAY THROUGH WEDNESDAY NIGHT...MODERATE CONFIDENCE. MVFR TO
IFR CIGS THROUGH MUCH OF THE DAY WITH MVFR VSBYS. MOSTLY RAIN IS
EXPECTED...HOWEVER AT THE ONSET COULD SEE -FZRA BETWEEN 9-13Z IN
NW MA. OTHERWISE...VERY ISOLD TSRA PSBL LATE WED INTO WED NIGHT
ESP ALONG THE SOUTH COASTS OF RI/MA. SE WIND GUSTS 25-35 KTS
PSBL WED. LLWS IS POSSIBLE DUE TO INVERSION.

KBOS TERMINAL...HIGH CONFIDENCE IN TAF. TIMING OF ONSET OF PRECIP
COULD BE AN HOUR OR TWO IN EITHER DIRECTION OF FORECAST.

KBDL TERMINAL...HIGH CONFIDENCE IN TAF. TIMING OF ONSET OF PRECIP
COULD BE AN HOUR OR TWO IN EITHER DIRECTION OF FORECAST.

OUTLOOK /THURSDAY THROUGH SUNDAY/...MODERATE CONFIDENCE

THURSDAY...HIGH CONFIDENCE. MAINLY VFR IN THE INTERIOR...BUT AREAS
OF MVFR CIGS/VSBYS IN LINGERING SHOWERS POSSIBLE SE NEW ENG

THURSDAY NIGHT INTO FRIDAY...MAINLY VFR INTERIOR. LOW CONFIDENCE ON
EXTENT OF ANOTHER PERIOD OF RAIN AND ASSOCD MVFR/IFR BACKING IN
ACROSS SE NEW ENG THU NIGHT WHICH WOULD CHANGE TO SNOW IF PRECIP
MAKES IT FAR ENOUGH WEST...THEN IMPROVING CONDITIONS FRI.

SATURDAY AND SUNDAY...MAINLY VFR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /THROUGH WEDNESDAY NIGHT/...

TONIGHT...HIGH CONFIDENCE.  HIGH PRESSURE MOVING OVER THE WATERS
WILL KEEP WINDS AND SEAS BELOW SMALL CRAFT CRITERIA.

WEDNESDAY AND WEDNESDAY NIGHT...MODERATE CONFIDENCE.  STRONG
SOUTHERLY WINDS WILL BUILD THROUGH THE DAY WITH GALE FORCE WINDS
EXPECTED WEDNESDAY AFTERNOON AND NIGHT.  HIGHEST CONFIDENCE IN GALE
FORCE WINDS IS ON THE EASTERN OUTER WATERS WHERE GALE WARNINGS HAVE
BEEN ISSUED.  ACROSS THE REMAINDER OF THE WATERS...CONFIDENCE IS
LOWER SO HAVE OPTED TO KEEP THE GALE WATCH FOR THE TIME BEING.
EITHER THE GALES ARE MARGINAL IN THESE AREAS...OR THEY ARE ONLY
EXPECTED TO LAST FOR A FEW HOURS.  SEAS INCREASE TO 5 TO 10 FEET ON
THE SOUTHERN WATERS AND 5 TO 8 FEET ON THE EASTERN WATERS AS A COLD
FRONT MOVES ACROSS THE WATERS WEDNESDAY NIGHT.

OUTLOOK /THURSDAY THROUGH SUNDAY/...HIGH CONFIDENCE...

THURSDAY...LIGHT W/NW WINDS...BUT SEAS 5-8 FT OVER SOUTHERN WATERS
IN LINGERING S SWELL. RAIN SHOWERS AND REDUCED VSBYS POSSIBLE
WATERS SOUTH AND EAST OF CAPE COD.

THU NIGHT AND FRI...INCREASING NW WINDS TO 20 KT WITH LOW PROB FOR A
FEW G25 KT. SCA SEAS PERSIST OVER OUTER WATERS. VSBYS POSSIBLY
REDUCED IN A PERIOD OF RAIN OVER WATERS SOUTH AND EAST OF CAPE COD
THU NIGHT WHICH COULD CHANGE TO SNOW SHOWERS...IMPROVING FRI.

SATURDAY...INCREASING SW WINDS WITH GUSTS TO 25 KT DEVELOPING
AFTERNOON/EVENING.

SUNDAY...WINDS TURNING NW WITH SPEEDS MOSTLY BELOW SCA.

&&

.CLIMATE...
RECORD HIGHS FOR FEB 3RD - 4TH...

BOS...59/1991 - 64/1991
BDL...61/1991 - 64/1991
PVD...60/1991 - 66/1991
ORH...57/1909 - 61/1991

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...GALE WATCH FROM WEDNESDAY AFTERNOON THROUGH LATE WEDNESDAY
     NIGHT FOR ANZ231>237.
     SMALL CRAFT ADVISORY FROM 7 AM WEDNESDAY TO 1 AM EST THURSDAY
     FOR ANZ230.
     GALE WARNING FROM 7 AM WEDNESDAY TO 4 AM EST THURSDAY FOR
     ANZ250-251-254.
     GALE WATCH FROM 7 AM EST WEDNESDAY THROUGH LATE WEDNESDAY
     NIGHT FOR ANZ255-256.

&&

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


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