Area Forecast Discussion
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FXUS61 KBOX 051449
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
1049 AM EDT THU MAY 5 2016

.SYNOPSIS...
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/...
1040 AM UPDATE...

LOW PRESSURE WAS SLOWLY DEEPING OFF THE NORTH CAROLINA COAST...
DOWN TO 997 MB AS OF 10 AM...ABOUT 1 MB DEEPER THAN THE MODELS.
WE CONTINUE TO BE SOCKED IN WITH A MOIST NORTHEAST FLOW. MESOSCALE
MODELS INDICATE THAT THE WESTERN EDGE OF THE RAIN SHIELD...WHICH
HAS ALREADY OVERSPREAD EASTERN CAPE COD/EASTERN MARTHAS VINEYARD/
NANTUCKET...WILL CONTINUE TO SLOWLY EXPAND WESTWARD THIS
AFTERNOON. AM EXPECTING IT TO GET AS FAR WEST AS I-495 IN MA AND
THE RI/CT/MA BORDER LATE THIS AFTERNOON/EARLY EVENING BEFORE
EXITING TO THE NORTHEAST TONIGHT. A FEW SHOWERS COULD BE LOCALLY
HEAVY ESPECIALLY ON THE CAPE AND ISLANDS. HAVE INCREASED POPS IN
EASTERN AREAS.

SOUNDINGS INDICATE WINDS ALREADY 30-35 KT AT 2000 FT IN RI AND
EASTERN MA. HAVE BEEN GETTING GOOD MIXING AND SURFACE GUSTS TO
NEAR 30 KT IN THOSE AREAS LATE THIS MORNING. MODELS INDICATE WINDS
INCREASING BY ANOTHER 5 KT OR SO THIS AFTERNOON/EVENING. THUS IT
WILL BECOME WINDY WITH GUSTS TO 35 KT...OR AROUND 40 MPH POSSIBLE
IN EASTERN MA AND RI. EXPECTING IT TO REMAIN BELOW WIND ADVISORY
CRITERIA OF 46 MPH GUSTS.

COASTAL SURGES RUNNING A TAD HIGHER THAN FORECAST. NO CHANGES TO
THE COASTAL FLOOD ADVISORY BUT HAVE TWEAKED VALUES A BIT UPWARD
FOR TONIGHT...SEE COASTAL DISCUSSION BELOW.

NO CHANGE TO TEMPERATURE FORECASTS FOR THIS PERIOD. STILL
FORECASTING HIGHS IN THE UPPER 40S TO MID 50S THIS AFTERNOON.

&&

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

RAIN SHIELD ASSOCIATED WITH COASTAL LOW WILL PULL AWAY FROM CAPE
COD AND THE ISLANDS AS DRY SLOT APPROACHES FROM THE SOUTH. THIS
MAY RESULT IN AREAS OF DRIZZLE AND FOG FORMING WITH DRY AIR ALOFT
AND MOIST NE LOW LEVEL FLOW ACROSS SOUTHERN NEW ENGLAND.

FRIDAY...

OTHER THAN SPOTTY LIGHT RAIN/DRIZZLE THE DAY SHOULD START OFF
MAINLY DRY. IN FACT SOME OF THE MODEL GUID SUGGEST THERE COULD BE
A FEW BREAKS OF SUNSHINE ACROSS CAPE COD AND NANTUCKET EARLY IN
THE MORNING. ALTHOUGH THIS WILL BE SHORT LIVED AS VERTICALLY
STACKED LOW TRACKS FROM THE MID ATLC TO THE NJ COAST. THIS ADVECTS
DEEP LAYER MOISTURE IN THE FORM OF RAIN INTO CT AND WESTERN-
CENTRAL MA FRI AFTN. PRECIP MAY NOT REACH EASTERN MA UNTIL AFTER
DARK.

IT WILL BECOME BREEZY ONCE AGAIN ACROSS EASTERN MA AS EAST WINDS
INCREASE.

&&

.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.

&&7 AM UPDATE...

.AVIATION /14Z THURSDAY THROUGH MONDAY/...
FORECASTER CONFIDENCE LEVELS...

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

1445Z UPDATE...

SHORT TERM /THROUGH FRIDAY/...

THIS AFTERNOON...WIDESPREAD IFR AND LOWER-END MVFR CIGS THIS
AFTERNOON...WITH THE LOWEST CEILINGS NEAR THE COAST AND AT ORH.
PATCHY FOG EASTERN HALF. RAIN...WITH LOCALLY HEAVY SHOWERS OVER
THE CAPE AND ISLANDS. RAIN MAY SPREAD WEST TO THE I-495 BELT IN
MA AND TO NEAR THE MA/CT/RI BORDER LATE THIS AFTERNOON/EARLY
EVENING. NE WINDS GUSTING TO 25-35 JT ACROSS E MA AND RI
TERMINALS THROUGH THIS EVENING.

TONIGHT...

TRENDS OF MVFR W AND IFR-LIFR E CONTINUE. -RA OVER E/SE NEW
ENGLAND WITH 25 TO 35 KT NE WINDS CONTINUES DURING THE EVENING
HOURS CONCLUDING TOWARDS MIDNIGHT. SOME IMPROVEMENT EXPECTED INTO
THE MORNING HOURS.

FRIDAY...

GRADUAL IMPROVEMENT IF EVER BRIEFLY. MVFR LIKELY. -RA DEVELOPING
LATE ALONG WITH NE WINDS.

KBOS TERMINAL...MODERATE CONFIDENCE CONCERNING THE TAF. WILL BRING
RAIN IN ON 20Z AND KEEP CONDITIONS LOW PRIOR TOWARDS IMPROVING
CONDITIONS SHORTLY AFTER MIDNIGHT.

KBDL TERMINAL...WILL KEEP -RA WEST. CONDITIONS IMPROVING LATER
TODAY POTENTIALLY UP TO LOW END VFR.

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.

1045 AM UPDATE...

THIS AFTERNOON...

GALE WARNING IS IN EFFECT. NE WINDS WILL HAVE FREQUENT GUSTS TO
30 TO 35 KT WITH A GUST TO 40 KT POSSIBLE OVER THE SE WATERS
TOWARD EVENING. SHOWERS...LOCALLY HEAVY...WITH AREAS OF FOG WILL
RESTRICT VISIBILITY TO 3 MILES OR LESS AT TIMES OVER THE WATERS.
SEAS BUILDING TO 8 TO 12 FEET ON THE OUTER WATERS.

TONIGHT...

NE GALES CONTINUE DURING THE EVENING FOLLOWED BY WINDS DIMINISHING
AFTER MIDNIGHT. VSBY MAY BE REDUCED IN AREAS OF FOG AND DRIZZLE AT
TIMES.

FRIDAY...

LOW PRES MOVES UP THE COAST FROM THE MID ATLC TO NJ. THIS WILL
RESULT IN EAST WINDS INCREASING AS THE DAY PROGRESSES ALONG WITH
RAIN OVERSPREADING THE RI WATERS IN THE AFTERNOON.

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...
930 AM UPDATE...

PRIOR FORECAST AND ADVISORY LOCATION LOOKS GOOD. HAVE ADJUSTED
SURGE AND SEAS UP A LITTLE BASED ON LATEST TRENDS AND HIGH
RESOLUTION WIND GUIDANCE. SURGE IS PRESENTLY RUNNING A LITTLE OVER
A FOOT AT BOSTON...CHATHAM AND NANTUCKET HARBOR OR ABOUT A HALF
FOOT ABOVE BOTH THE ESTOFS AND ETSS GUIDANCE. WOULD ANTICIPATE THE
PERSISTENT NE FLOW WHICH MAY STRENGTHEN A TAD THIS EVENING TO
RESULT IN A MODEST AND GRADUAL INCREASE IN SURGE. IT IS NOT OUT OF
THE QUESTION THAT A FEW SPOTS...SUCH AS SCITUATE AND NANTUCKET
HARBOR...MAY APPROACH THE HIGH END OF MINOR IMPACTS FOR THIS
EVENING/S HIGH TIDE. HAVE KEPT THE ESSEX COUNTY COASTLINE OUT OF
THE ADVISORY AREA FOR NOW BUT WILL REEVALUATE LATER TODAY. AT
LEAST POCKETS OF MINOR COASTAL FLOODING POSSIBLE AGAIN FRI EVENING
DUE TO HIGH ASTRO TIDE AND PROBABLE SLOWNESS FOR THE SURGE TO
EVACUATE...BUT WE DO NOT THINK THIS WARRANTS A DOUBLE HEADLINE AT
THIS TIME.

COASTAL FLOOD ADVISORY HAS BEEN POSTED FOR THIS EVENING/S HIGH TIDE.
ASTRO TIDE AT BOSTON IS 11.95 FT AT 10:55 PM. NE WINDS OF 25 TO 35
KT THIS AFTERNOON AND EVENING WILL RESULT IN A STORM SURGE AROUND 1
FT. THIS COMBINED WITH SOME WAVE ACTION ONTOP OF THE SURGE WILL BE
SUFFICIENT TO PRODUCE MINOR COASTAL FLOODING ALONG THE EASTERN MA
COASTLINE FROM BOSTON SOUTHWARD THRU PLYMOUTH COUNTY...CAPE COD BAY
AND NANTUCKET. RISK IS LOWER NORTH OF BOSTON BUT LATER SHIFTS WILL
HAVE TO EVALUATE FOR POTENTIAL HEADLINES.

&&

.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 UNTIL 2 AM EDT FRIDAY FOR ANZ231>235-237.
     GALE WARNING UNTIL 10 PM EDT THIS EVENING FOR ANZ230-236.
     GALE WARNING UNTIL 2 AM EDT SATURDAY FOR ANZ250-251-254>256.

&&

$$
SYNOPSIS...NOCERA/SIPPRELL/FIELD
NEAR TERM...NOCERA/FIELD
SHORT TERM...NOCERA
LONG TERM...SIPPRELL
AVIATION...NOCERA/SIPPRELL/FIELD
MARINE...NOCERA/SIPPRELL/FIELD
TIDES/COASTAL FLOODING...THOMPSON/STAFF



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