Area Forecast Discussion
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000
FXUS61 KBOX 020601
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
100 AM EST MON MAR 2 2015

.SYNOPSIS...

DRY AND BLUSTERY WEATHER TODAY BEHIND A COLD FRONT. LOW PRESSURE
FROM NORTHERN CANADA AND ASSOCIATED LOW FORMING OVER THE PLAINS
MONDAY WILL MERGE...THEN PASS WEST AND NORTH OF NEW ENGLAND. THIS
WILL SWING A COLD FRONT ACROSS THE REGION ON WEDNESDAY. DRY AND COLD
WEATHER RETURNS FOR THE END OF THE WEEK. ANOTHER COLD FRONT MOVES
THROUGH ON SATURDAY.

&&

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

1 AM UPDATE...

LAST GASP OF SNOW ACROSS RHODE ISLAND AND EASTERN MA WILL BE QUICKLY
EXITING THE REGION IN THE NEXT HOUR.  PTYPE HAS CHANGED TO
RAIN ACROSS THE CAPE/ISLANDS AND THAT WILL ALSO BE ENDING SHORTLY.
WE SHOULD BE ABLE TO TAKE DOWN ALL THE WINTER WEATHER HEADLINES
VERY SHORTLY.

OTHERWISE...AN ABUNDANCE OF MID LEVEL CLOUDINESS WILL HANG TOUGH
OVERNIGHT.  A COLD FRONT WILL CROSS THE REGION TOWARD MORNING...BUT
THE WINDS WILL NOT PICKUP TOO MUCH UNTIL AFTER SUNRISE.  LOW TEMPS
WILL GENERALLY REMAIN IN THE 20S WITH A LOT OF CLOUDS PERSISTING.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TUESDAY/...
MONDAY...
PRECIPITATION WILL HAVE LARGELY COME TO AN END FOR DAYBREAK MONDAY
WITH THE LOW PRESSURE RAPIDLY PULLING AWAY INTO THE CANADIAN
MARITIMES AND DRIER AIR/HIGH PRESSURE MOVING IN FROM THE WEST.
INCREASING SUNSHINE EXPECTED DURING THE DAY...WITH TEMPS TOPPING
OUT IN THE UPPER 20S TO MID 30S. HOWEVER AS WE GET TOWARDS
MIDDAY/AFTERNOON TIGHTENING GRADIENT WILL ALLOW NORTHWEST FLOW TO
BECOME BLUSTERY...WITH GUSTS OF 25 TO 30 MPH...25 TO 35 MPH ON THE
CAPE AND ISLANDS.

MONDAY NIGHT...
HIGH PRESSURE SETTLES OVER THE AREA WITH CLEAR SKIES EXPECTED.
GIVEN OUR SNOWPACK IN PLACE AND LIGHT WINDS...SHOULD BE ANOTHER
NIGHT FOR EXCELLENT RADIATIONAL COOLING. BECAUSE OF THIS DID
GENERALLY GO BELOW MODEL GUIDANCE FOR MIN TEMPS...LOOKING TO
ANTICIPATED SURFACE DEWPOINTS FOR A GUIDELINE ON HOW LOW WE CAN
GO. MAY SEE SOME SPOTS IN THE INTERIOR DROP BELOW ZERO.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
BIG PICTURE... THE BROAD UPPER FLOW CONTINUES TO FEATURE A TROUGH
TRANSITING EAST ACROSS THE COUNTRY...REACHING THE EASTERN USA DURING
THE LATE WEEK AND LINGERING THROUGH THE WEEKEND. MEANWHILE AN UPPER
RIDGE SHIFTS FROM THE PACIFIC OCEAN BACK ASHORE ONTO THE WEST COAST.
CONTOUR HEIGHTS IN THE TROUGH ARE LOWEST THURSDAY-FRIDAY AND NEAR
NORMAL OVER THE WEEKEND. THIS MEANS A TREND TO COLDER TEMPS THURSDAY-
FRIDAY FOLLOWED BY A TREND CLOSER TO NORMAL OVER THE WEEKEND.

DAILIES...

TUESDAY... HIGH PRESSURE OVER THE REGION MOVES OFFSHORE BY AFTERNOON
WITH AIRFLOW SWINGING FROM NORTHWEST TO SOUTHWEST. THE SURFACE
AIRMASS STARTS OUT QUITE DRY WITH DEW POINTS IN THE SINGLE NUMBERS
BELOW ZERO TO START...CLIMBING TO 5-10 ABOVE BY EVENING. MODEL CROSS
SECTIONS SHOW INCREASING MOISTURE MORNING AND AFTERNOON ABOVE 700
MB. THIS SUGGESTS INCREASING MID AND HIGH CLOUDS WHILE DRY BENEATH.
LOW LEVEL JETS FROM THE CAROLINAS AND MIDWEST AND THE SURFACE
PRESSURE GRADIENT ALL SUGGEST THE INFLOW AND ISENTROPIC LIFT WILL
REMAIN TO OUR WEST THROUGH THE DAY...POSSIBLY ENTERING WESTERN MA/CT
AT OR AFTER 21Z. SO WE EXPECT INCREASING CLOUDS TUESDAY BUT
OTHERWISE DRY WEATHER THROUGH THE DAY. POSSIBLE LIGHT SNOW AROUND
THE EVENING RUSH HOUR IN THE CT RIVER VALLEY. TEMPS SHOULD REACH THE
MID 20S TO AROUND 30.

TUESDAY NIGHT-WEDNESDAY... NORTHERN AND SOUTHERN STREAM SHORTWAVES
MERGE OVER THE GREAT LAKES AND TRACK INTO CANADA. THIS BRINGS A MILD
FLOW OF AIR UP OVER NEW ENGLAND. THE LEADING EDGE OF THIS AIR
REACHES WESTERN SECTIONS TUESDAY EVENING AND EASTERN SECTIONS
TUESDAY NIGHT. TEMPERATURE PROFILES SUPPORT AN INITIAL PERIOD OF
SNOW CHANGING TO RAIN OR FREEZING RAIN OVERNIGHT. ACTUALLY...THE
MODELS MAY NOT BE HANDLING WELL THE CHILLING MASS OF SNOW AND COLD
GROUND /A.K.A. THE GIANT ICECUBE/ WHICH WOULD MEAN THE ACTUAL MAX
SFC TEMPS WILL BE COOLER THAN MODEL FORECASTS. TEMPERATURES AT 925
AND 950 MB WILL BE IN THE 30S...SO EXPECT SURFACE TEMPS NO HIGHER
THAN THE LOWER 40S.

THE SURFACE LOW PRESSURE AREA PASSES WELL NORTH OF NEW ENGLAND
WEDNESDAY AND SWINGS A COLD FRONT THROUGH THE REGION DURING THE
AFTERNOON OR EVENING. MOISTURE CROSS SECTIONS SHOW DECREASING RH IN
THE LIFT AND NUCLEATION ZONES ALOFT WEDNESDAY MORNING...SO THE TREND
THROUGH THE DAY SHOULD BE TO DIMINISHING POPS.

THURSDAY-FRIDAY... THE WEDNESDAY COLD FRONT WILL ALIGN WITH THE
UPPER FLOW AS IT MOVES SOUTH OF NEW ENGLAND...SLOWING ITS OFFSHORE
PROGRESS TO A CRAWL. MEANWHILE WE WILL BE UNDER THE RIGHT ENTRANCE
REGION OF THE SUPPORTING UPPER JET...A SOURCE OF UPPER VENTING. THIS
SHOULD SUPPORT LINGERING CLOUDS AND A CHANCE OF PCPN...WITH TEMPS
SUPPORTIVE OF SNOW. BEST CHANCE SOUTH COAST...LESSER CHANCE FARTHER
NORTH. THE JET AND SURFACE FRONT SWEEP OFFSHORE THURSDAY NIGHT. HIGH
PRESSURE THEN MOVES OVER THE EASTERN USA FOR FRIDAY. TEMPS ALOFT
SUPPORT MAX SFC TEMPS IN THE 20S.

SATURDAY-SUNDAY... ANOTHER NORTHERN STREAM SHORTWAVE AND COLD FRONT
SWINGS THROUGH THE FLOW SATURDAY. CROSS SECTIONS SHOW SOME MOISTURE
ALOFT BUT MOST OF IT IS CONCENTRATED TO OUR NORTH.  ALSO JUST
LIMITED LIFT TO WORK ON THAT MOISTURE. WE WILL HAVE 25-50 PCT SKY
COVER AND NIL POPS. HIGH PRESSURE THEN BUILDS FOR SUNDAY.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /TODAY THROUGH TUESDAY/...

TODAY...HIGH CONFIDENCE.  LEFT OVER MVFR-IFR CONDITIONS IN LIGHT
SNOW SHOULD IMPROVE TO VFR BY 7 OR 8Z.  OTHERWISE...EXPECT VFR
CONDITIONS DESPITE A SCATTERED TO EVEN BROKEN DECK OF STRATO-CUMULUS
CLOUDS.  WEST TO NORTHWEST WIND GUSTS OF 25 TO 35 ARE EXPECTED TO
DEVELOP LATER THIS MORNING AND CONTINUE INTO THE AFTERNOON.

TONIGHT...HIGH CONFIDENCE.  WINDS GRADUALLY DIMINISH THIS EVENING
WITH VFR CONDITIONS CONTINUING.

TUESDAY...MODERATE TO HIGH CONFIDENCE.  VFR CONDITIONS
THROUGH AT LEAST MID AFTERNOON.  MVFR-IFR CONDITIONS MAY DEVELOP BY
LATE TUE AFTERNOON/EARLY EVENING ACROSS WESTERN MA/NORTHERN CT AS
SNOW OVERSPREADS THE REGION.

KBOS TAF...HIGH CONFIDENCE.  NORTHWEST WIND GUSTS OF 25 TO 35 KNOTS
LATER THIS MORNING AND AFTERNOON.

KBDL TAF...HIGH CONFIDENCE.  NORTHWEST WIND GUSTS OF 25 TO 35 KNOTS
LATER THIS MORNING AND AFTERNOON.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...

TUESDAY NIGHT-WEDNESDAY...MODERATE CONFIDENCE. CONDITIONS LOWERING
TO IFR/LIFR. INITIALLY SNOW BUT CHANGING TO SLEET/FREEZING RAIN
DURING THE NIGHT AND RAIN IN THE COASTAL PLAIN OVERNIGHT. PCPN
CHANGES TO RAIN ALL AREAS WEDNESDAY...BUT COLD SURFACES COULD
MAINTAIN A FREEZING RAIN ELEMENT WEDNESDAY MORNING. COLDER AIR MOVES
IN WEDNESDAY NIGHT CHANGING ANY RAIN TO SNOW.

THURSDAY...LOW CONFIDENCE. VFR NORTH OF A HFD-BOS LINE. MVFR CIGS
AND AREAS OF MVFR/IFR VSBYS IN SNOW...DIMINISHING BY EVENING.
NORTHWEST WINDS GUSTING TO 20 KNOTS.

FRIDAY...MODERATE CONFIDENCE. VFR.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

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

A WEAK WAVE OF LOW PRESSURE MOVES ACROSS THE WATERS TONIGHT.
THIS SYSTEM REALLY INTENSIFIES AS IT MOVES INTO THE CANADIAN
MARITIMES NEAR DAYBREAK MONDAY...SO WESTERLY WIND GUSTS MAY REACH
20 TO 25 KNOTS NEAR 12Z MONDAY. OTHERWISE...RAIN AND SNOW THIS
EVENING AND TONIGHT WILL REDUCE VISIBILITIES AT TIMES FOR
MARINERS.

MONDAY...AS THE LOW PRESSURE GOING INTO THE CANADIAN MARITIMES
INTENSIFIES...INCREASING NORTHWEST WINDS ARE EXPECTED OVER THE
SOUTHERN NEW ENGLAND COASTAL WATERS...WITH GALE FORCE GUSTS
EXPECTED. GALE WARNINGS HAVE BEEN HOISTED FOR ALL COASTAL WATERS
FROM MIDDAY MONDAY INTO MONDAY NIGHT.

OUTLOOK...TUESDAY THROUGH FRIDAY..MODERATE CONFIDENCE.

TUESDAY... LINGERING 5 FOOT SEAS SOUTH AND EAST OF NANTUCKET IN THE
MORNING BUT DIMINISHING. NORTHWEST WINDS DIMINISHING FROM 20 KNOTS.
ANY SMALL CRAFT ADVISORY SHOULD END IN THE MORNING.

TUESDAY NIGHT-WEDNESDAY...SOUTH TO SOUTHWEST WINDS WILL INCREASE TO
20-25 KNOTS. SEAS WILL BUILD 6 TO 10 FEET ON THE OUTER WATERS AND ON
RI SOUND. REDUCED VSBYS...INITIALLY SNOW BUT CHANGING TO RAIN. A
SMALL CRAFT ADVISORY MAY BE NEEDED.

THURSDAY...NORTHWEST WIND GUSTING TO 25 KNOTS. SEAS 5 TO 8 FEET
MAINLY ON THE OUTER WATERS...DIMINISHING LATE. A SMALL CRAFT
ADVISORY MAY BE NEEDED.

FRIDAY... SHIFTING WINDS LESS THAN 20 KNOTS. SEAS LESS THAN 5 FEET.
QUIET WEATHER.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...WINTER WEATHER ADVISORY UNTIL 4 AM EST EARLY THIS MORNING FOR
     CTZ002>004.
MA...WINTER STORM WARNING UNTIL 4 AM EST EARLY THIS MORNING FOR
     MAZ017>021.
     WINTER WEATHER ADVISORY UNTIL 4 AM EST EARLY THIS MORNING FOR
     MAZ002>016-022-023-026.
RI...WINTER STORM WARNING UNTIL 4 AM EST EARLY THIS MORNING FOR
     RIZ002>008.
     WINTER WEATHER ADVISORY UNTIL 4 AM EST EARLY THIS MORNING FOR
     RIZ001.
MARINE...GALE WARNING FROM 11 AM THIS MORNING TO 4 AM EST TUESDAY FOR
     ANZ231-232-250-251-254-255.
     GALE WARNING FROM 11 AM THIS MORNING TO 11 PM EST THIS EVENING
     FOR ANZ233>235-237-256.
     GALE WARNING FROM 11 AM THIS MORNING TO 8 PM EST THIS EVENING
     FOR ANZ230-236.

&&

$$
SYNOPSIS...WTB/NMB
NEAR TERM...FRANK
SHORT TERM...NMB
LONG TERM...WTB
AVIATION...FRANK/WTB
MARINE...WTB/NMB


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