Area Forecast Discussion
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062
FXUS61 KBOX 050736
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
336 AM EDT THU MAY 5 2016

.SYNOPSIS...

 * UPDATES TO LONG TERM PORTION OF THE FORECAST...

CLOUDY...DREARY AND COOL WEATHER CONTINUES THROUGH FRIDAY WITH
PERIODS OF RAIN AS WAVES OF LOW PRESSURE TRACK NEAR SOUTHERN NEW
ENGLAND. DESPITE SOME SHOWERS POSSIBLE THIS WEEKEND THERE WILL BE
MANY HOURS OF DRY WEATHER ALONG WITH MODERATING TEMPERATURES.
SIGNIFICANT IMPROVEMENT WILL LIKELY OCCUR EARLY TO MIDDLE OF NEXT
WEEK AS HIGH PRESSURE BUILDS IN WITH MUCH MILDER TEMPERATURES.

&&

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

DRY SLOT HAS OVERSPREAD THE REGION BRINGING AN END TO THE STEADY
RAINS FROM LAST EVENING. HOWEVER MOIST LOW LEVEL NE JET PROVIDING
LOW CLOUDS ALONG WITH AREAS OF DRIZZLE AND FOG. NE WINDS OFF THE
CHILLY OCEAN WATERS WILL KEEP TEMPS IN THE LOW TO MID 40S WITH
UPPER 30S ACROSS THE HIGHER TERRAIN SUCH AS WORCESTER. THESE
CONDITIONS WILL PERSIST INTO DAYBREAK.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...

*** UNSEASONABLY COOL/DREARY WEATHER CONTINUES THURSDAY/THURSDAY
NIGHT WITH A PERIOD OF STEADY RAIN LIKELY LATE IN THE AFTERNOON AND
EVENING ACROSS EASTERN NEW ENGLAND ***

THURSDAY AND THURSDAY NIGHT...

ANOTHER WAVE OF LOW PRESSURE WILL BE TRACKING SOUTHEAST OF SOUTHERN
NEW ENGLAND THURSDAY INTO THURSDAY EVENING.  THIS COMBINED WITH HIGH
PRESSURE OVER THE CANADIAN MARITIMES WILL RESULT IN ANOTHER
DREARY/UNSEASONABLY COOL DAY ACROSS THE REGION.  THIS NEXT WAVE OF
LOW PRESSURE WILL BE A BIT STRONGER THAN THE PAST FEW...SO NORTHEAST
WIND GUSTS OF 20 TO 30 MPH ARE EXPECTED ACROSS THE EASTERN HALF OF
SOUTHERN NEW ENGLAND WITH PERHAPS A FEW GUSTS TO 35 MPH.  HIGH TEMPS
ON THURSDAY WILL ONLY BE IN THE UPPER 40S TO AROUND 50 IN MOST
LOCATIONS.  GUSTY WINDS ALONG THE COASTAL PLAIN WILL RESULT IN WIND
CHILLS IN THE UPPER 30S TO THE LOWER 40S IN THIS REGION!

AS FOR PRECIPITATION...GIVEN MOIST ONSHORE FLOW...LOW CLOUDS ALONG
WITH SCATTERED SHOWERS/AREAS OF DRIZZLE AND PATCHY FOG ARE EXPECTED
THU INTO THU NIGHT.  A PERIOD OF STEADIER RAINFALL WILL PROBABLY
OCCUR LATE THURSDAY AFTERNOON AND EVENING ACROSS EASTERN NEW
ENGLAND. THIS WILL DEPEND ON EXACTLY HOW CLOSE INTENSIFYING LOW
PRESSURE AND ITS ASSOCIATED DEEPER MOISTURE/FORCING TRACK IN REGARDS
TO THE SOUTHERN NEW ENGLAND COAST.  ECMWF/NAM ARE THE MOST ROBUST
SHOWING 40 TO 50 KNOTS OF NORTHEAST WINDS AT 925 MB...WHILE THE GFS
IS WEAKER. EITHER WAY...GIVEN THAT TYPE OF NORTHEAST LOW LEVEL FLOW
THERE SHOULD BE A PERIOD OF STEADIER RAIN AT LEAST ALONG THE EASTERN
MA COAST.

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...

*/ HIGHLIGHTS...

 - DREARY WEATHER OF LIGHT RAIN / DRIZZLE FRIDAY NIGHT - SATURDAY
 - COLD FRONT AND BEST CHANCES OF RAIN ON SUNDAY
 - QUICK BLAST OF COLDER AIR MONDAY MORNING BEHIND THE FRONT...DRY
 - POSSIBLE PROLONGED PERIOD OF UNSETTLED WEATHER THRU THE WEEK

*/ DISCUSSION...

TACKLING AN ENSEMBLE FORECAST APPROACH WITH A BROADER VIEW...BLOCKY
FLOW PATTERN DEAMPLIFIES WHILE SEEMINGLY TO SUBTLY SHIFT E OVER THE
COURSE OF NEXT WEEK. RIDGING PREVAILS ACROSS THE NE PACIFIC INTO THE
GULF OF ALASKA WITH TROUGHING OVER THE N-CENTRAL CONUS. DOWNSTREAM
RIDGING IS PREFERRED OVER THE NE CONUS WITH A FAVORABLE ENVIRONMENT
FOR STORM DEVELOPMENT S OF GREENLAND. PERHAPS A CONSEQUENCE OF POOR
FORECAST CONSENSUS OF THE PACIFIC NORTH AMERICA PATTERN...WHAT WAS
JUST A DAY OR TWO AGO A FORECAST OF DRY WEATHER AND TEMPERATURES
INTO THE 70S HAS BEEN COMPLETELY OBLITERATED INTO RENEWED PERIOD
OF DREARY WET WEATHER.

SO AN INITIAL WET AND DREARY PERIOD BENEATH A DYING LOW OCCLUSION
FRIDAY NIGHT INTO SATURDAY. SHOWERS ERODING INTO POCKETS OF LIGHT
RAIN / DRIZZLE AS DRIER AIR WRAPS INTO THE SYSTEM. TRICKY FORECAST
THAT WARRANTS AT LEAST CHANCE POPS. OVERALL SATURDAY INTO SATURDAY
NIGHT DOES NOT APPEAR TO BE A WASH-OUT...PERHAPS THE SALVAGEABLE DAY
OF THE WEEKEND PRIOR TO THE DISMAL WEATHER CONCLUDING SUNDAY AS A
N-STREAM DISTURBANCE AND ATTENDANT COLD FRONT SWEEPS NEW ENGLAND
WITH THE BEST AND LIKELY CHANCES OF RAIN. BEHIND THIS FRONT WILL
SEE A QUICK BLAST OF COLD AIR ADVECTION AND BREEZY W/NW FLOW.
OVERALL TEMPERATURES THROUGHOUT THE AFOREMENTIONED FORECAST PERIOD
REMAINING BELOW-AVERAGE.

THEREAFTER A LOW CONFIDENCE FORECAST. FROM AN ENSEMBLE APPROACH IT
WOULD APPEAR ENERGY OUT OF THE N-CENTRAL CONUS DEAMPLIFIES BENEATH A
MID-UPPER LEVEL CONFLUENT FLOW PATTERN AND FAVORABLE RIDGING. BUT IN
EVALUATING DETERMINISTIC GUIDANCE...VARIANCE IS EVIDENT IN HANDLING
INDIVIDUAL WAVES THROUGH THE MID LEVEL FLOW WITH THE 05.0Z ECMWF
HIGHLIGHTING A MORE ROBUST N STREAM WAVE AROUND MIDWEEK. LEANING ON
AN ENSEMBLE-WEIGHTED FORECAST WILL LEAN TOWARDS A FORECAST OF WAVE
ENERGY SWEEPING ALONG A STALLED W TO E FRONTAL BOUNDARY BETWEEN THE
C-CONUS AND STORMS DEVELOPING S OF GREENLAND. NO CERTAINTY ON THE
EXACT FRONTAL BOUNDARY / BAROCLINIC ZONE BUT A PROLONGED PERIOD
LOOKS PLAUSIBLE OF NUISANCE LIGHT TO MODERATE RAIN UNDER BROKEN TO
OVERCAST CONDITIONS WHICH WILL MAKE CONDITIONS COOLER THAN AVERAGE
TOWARDS MID MAY. CAN NOT RULE OUT SOME BREAKS IN-BETWEEN AND SUN-
SHINE...AND IF THE BOUNDARY LAYER IS ABLE TO MIX OUT AND H85
TEMPERATURES HOVER AROUND +10C WE COULD SEE SEASONABLE TEMPERATURES
AROUND THE 60S. AGAIN...A LOW CONFIDENCE FORECAST FROM TUESDAY INTO
THE FOLLOWING WEEKEND.

&&

.AVIATION /08Z THURSDAY THROUGH MONDAY/...

FORECASTER CONFIDENCE LEVELS...

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

10 PM UPDATE ...

SHORT TERM /THROUGH FRIDAY/ ... HIGH CONFIDENCE ON TRENDS BUT
LOWER ON EXACT DETAILS.

THRU 12Z ... PERSISTENCE A GOOD SHORT TERM FORECAST IN THIS
REGIME. THUS EXPECT MVFR ACROSS CT RVR VLY WITH IFR ELSEWHERE.
MAINLY DRY BUT AREAS OF DRIZZLE POSSIBLE. GUSTY NE WINDS UP TO 25
KT WITH STRONGEST WINDS ALONG THE IMMEDIATE COAST.

AFTER 12Z ... MVFR ACROSS CT RVR VLY SPREADS EASTWARD INTO RI AND
CENTRAL MA HOWEVER IFR LIKELY LINGERS ACROSS EASTERN MA. NE WINDS
INCREASE TO 30-35 KT LATE IN THE DAY OVER EASTERN MA. RAIN
REDEVELOPS ACROSS EASTERN MA AROUND 21Z AND THEREAFTER.

TONIGHT ... MVFR EXCEPT IFR EASTERN MA IN STEADY RAIN BUT THEN A
DRYING TREND AFTER MIDNIGHT ALONG WITH IFR CONFINED TO ONLY
SOUTHEAST MA. GUSTY NE WINDS 30-35 KT ACROSS EASTERN MA SLOWLY
EASE LATE.

FRI ... MVFR LIKELY WITH RAIN REDEVELOPING LATE IN THE DAY ACROSS
CT. NE WINDS FAIRLY LIGHT EARLY BUT THEN BEGINNING TO INCREASE
LATE IN THE DAY.

KBOS TERMINAL ... UNCERTAINTY IN TAF CENTERED ON POTENTIAL
STEADY/HEAVY RAIN 21Z TODAY THRU 03Z THIS EVENING. HEAVIEST RAIN
MAY REMAIN OFFSHORE. OTHERWISE ANY RAIN TODAY WILL BE LIGHT AND
SPOTTY.

KBDL TERMINAL ... HIGH CONFIDENCE IN TAF.

OUTLOOK /FRIDAY NIGHT - MONDAY NIGHT/...MODERATE CONFIDENCE.

LOW END VFR TO LIFR MIX WITH LOW CIGS AND VSBY RESTRICTIONS PER
SHRA/DZ/BR INITIALLY...IMPROVING THROUGH SATURDAY. E WINDS VEER S
WHILE INCREASING AHEAD OF A COLD FRONT SWEEPING TERMINALS SUNDAY
WITH GUSTS UP TO 25 KTS. POSSIBLE LLWS AND LIKELY -RA/RA IMPACTS
PRIOR TO THE COLD FRONT...BEHIND WHICH WINDS BACK W/NW AND ARE
IMMEDIATELY GUSTY WITH UP TO 30 KTS SUNDAY NIGHT INTO MONDAY
MORNING. IMPROVING VFR WHILE WINDS W/NW WINDS DIMINISH MONDAY INTO
MONDAY NIGHT.

&&

.MARINE...

FORECASTER CONFIDENCE LEVELS...

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

10 PM UPDATE ...

ISOLATED T-STORM CAPE COD AND NANTUCKET WATERS TIL MIDNIGHT.
OTHERWISE STEADY RAIN TAPERS OFF TO LIGHT RAIN/DRIZZLE OVERNIGHT.
GUSTY NE WINDS OF 20-30 KT CONTINUES OVERNIGHT YIELDING ROUGH
OCEAN WATERS. EARLIER DISCUSSION BELOW.

========================================================================

SHORT TERM /THROUGH FRIDAY/...HIGH CONFIDENCE.

A COUPLE WAVES OF LOW PRESSURE COMBINED WITH A HIGH OVER THE
CANADIAN MARITIMES WILL RESULT IN PERSISTENT NORTHEAST WIND GUSTS OF
20 TO 30 KNOTS THROUGH THURSDAY EVENING...BEFORE GRADUALLY
DIMINISHING.  THE STRONGEST OF THOSE WINDS ARE EXPECTED LATE
THURSDAY MORNING INTO THE AFTERNOON...WHERE THERE IS A LOW RISK FOR
A FEW LOCATIONS TO BRIEFLY TOUCH 35 KNOTS.  SCA HEADLINES ARE POSTED
FOR ALL WATERS. OTHER CONCERNS FOR MARINERS WILL BE A FEW EMBEDDED
THUNDERSTORMS THIS EVENING...MAINLY ACROSS OUR SOUTHERN WATERS.
PATCHY FOG MAY ALSO AFFECT THE REGION AT TIMES THROUGH THURSDAY
NIGHT.

OUTLOOK /FRIDAY NIGHT - MONDAY NIGHT/...MODERATE CONFIDENCE.

WET WEATHER CONTINUES FRIDAY NIGHT UNDER E/NE FLOW WITH POTENTIAL
VISIBILITY RESTRICTIONS. CONDITIONS IMPROVE SATURDAY INTO SATURDAY
NIGHT AS E WINDS VEER S ALLOWING WAVE ACTION TO DIMINISH. BUT SHORT
LIVED AS S WINDS INCREASE AHEAD OF A COLD FRONT SWEEPING THE WATERS
LATE SUNDAY. GUSTS TO 25 KTS AHEAD OF THE FRONT WITH WAVES BUILDING
5 TO 7 FEET...BACKING W/NW WITH GUSTS TO 30 KTS IMMEDIATELY BEHIND
THE FRONT DIMINISHING MONDAY INTO MONDAY NIGHT ALLOWING WAVES TO
DIMINISH BELOW 5 FEET BY THE END OF PERIOD.

&&

.TIDES/COASTAL FLOODING...

HIGH ASTRONOMICAL TIDES OCCUR LATE THURSDAY EVENING THROUGH THE
WEEKEND.

FORTUNATELY...SEAS/WINDS WILL BE BELOW THRESHOLDS FOR A SIGNIFICANT
COASTAL FLOOD EVENT.  HOWEVER...THE POTENTIAL FOR POCKETS OF MINOR
SPLASH OVER/MINOR COASTAL FLOODING EXIST ALONG THE EASTERN MA COAST
DURING THE LATE THURSDAY EVENING AND LATE FRIDAY EVENING HIGH TIDES.

THE ASTRONOMICAL HIGH TIDE LATE THURSDAY EVENING IS 12.0 FEET AT
BOSTON AND THE LATE FRIDAY EVENING IS 12.3 FEET.  THE WINDS WILL BE
A BIT STRONGER THURSDAY EVENING...ESPECIALLY A FEW HOURS BEFORE
ASTRO HIGH TIDE...BUT THE LATE FRIDAY EVENING HIGH TIDE IS A TAD
HIGHER.  ALL IN ALL...POCKETS OF SPLASH OVER/MINOR COASTAL FLOODING
ARE A DECENT POSSIBILITY IN THE TYPICALLY VULNERABLE AREAS.  A
COASTAL FLOOD ADVISORY MAY EVENTUALLY BE NEEDED FOR BOTH THESE HIGH
TIDE CYCLES.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...

CT...NONE.
MA...COASTAL FLOOD ADVISORY FROM 9 PM THIS EVENING TO 1 AM EDT
     FRIDAY FOR MAZ015-016-019-022-024.
RI...NONE.
MARINE...GALE WARNING FROM NOON TODAY TO 2 AM EDT FRIDAY FOR ANZ231>235-
     237.
     GALE WARNING FROM NOON TODAY TO 10 PM EDT THIS EVENING FOR
     ANZ230-236.
     GALE WARNING FROM NOON TODAY TO 2 AM EDT SATURDAY FOR ANZ250-
     251-254>256.

&&

$$

SYNOPSIS...FRANK/SIPPRELL
NEAR TERM...NOCERA
SHORT TERM...FRANK
LONG TERM...SIPPRELL
AVIATION...NOCERA/SIPPRELL
MARINE...NOCERA/SIPPRELL
TIDES/COASTAL FLOODING...WFO BOX STAFF



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