Area Forecast Discussion
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000
FXUS61 KBOX 241523
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
1123 AM EDT SUN MAY 24 2015

.SYNOPSIS...
SOUTHWEST WINDS WILL BRING WARMER AIR INTO SOUTHERN NEW ENGLAND
BEGINNING TODAY. WARM AND MUGGY CONDITIONS BUILD INTO MIDWEEK
AHEAD OF INCREASING CHANCES OF SHOWERS AND THUNDERSTORMS. COULD
REMAIN WET ALL THE WAY THROUGH INTO NEXT WEEKEND.

&&

.NEAR TERM /UNTIL 7 PM THIS EVENING/...

11 AM UPDATE...

OTHER THAN A FEW BRIEF PUFFY CUMULUS CLOUDS THAT DEVELOPED AND
DISSIPATED ACROSS N CENTRAL AND NE MA OVER THE LAST FEW HOURS...
SKIES HAVE BEEN MAINLY CLEAR THROUGH LATE THIS MORNING. PRETTY
GOOD W-SW FLOW IN PLACE ESPECIALLY NEAR THE COAST AND...WITH GOOD
MIXING...NOTING GUSTS UP TO AROUND 25 KT MAINLY OVER THE NEAR
SHORE WATERS. TEMPS HAVE RESPONDED NICELY AS WELL. READINGS AT 15Z
MAINLY IN THE LOWER-MID 70S EXCEPT LOWER-MID 60S ALONG THE
IMMEDIATE S COAST WITH THE ONSHORE FLOW.

NEAR TERM FORECAST IN GOOD SHAPE BUT HAVE UPDATED TO BRING
CONDITIONS CURRENT.

PREVIOUS DISCUSSION...
EXPECT WINDS TO DIMINISH TOWARD EVENING AS BOUNDARY LAYER BEGINS
TO STABILIZE...ASIDE FROM S COAST WHERE IT WILL TAKE A BIT LONGER.

&&

.SHORT TERM /7 PM THIS EVENING THROUGH 6 PM MONDAY/...
SW FLOW PERSISTS TONIGHT AND MON AS MODELS BRING WARM FRONT
THROUGH UPSTATE NY AND NORTHERN NEW ENGLAND...WHICH SHOULD BE
FOCUS FOR ANY SHOWERS OR STORMS. 00Z GFS SEEMS OVERDONE IN
BRINGING PRECIPITATION THIS FAR E...ESPECIALLY GIVEN RISING 500 MB
HEIGHTS AND LACK OF DEEP MOISTURE OR APPRECIABLE LIFT OVER OUR
AREA. AS A RESULT WE DO EXPECT TO SEE AN INCREASE IN CLOUDINESS
/MAINLY MID LEVEL/ WITH PERHAPS AN ISOLATED SHOWER OR STORM MON
ACROSS NW MA.

LOWS WILL DROP BACK INTO 50S TONIGHT AND ONCE AGAIN CLIMB INTO
70S/LOWER 80S MON EXCEPT 60S ON S COAST...CAPE COD AND ISLANDS.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
*/ HIGHLIGHTS...

 - WARM MUGGY AND DRY TUESDAY INTO TUESDAY NIGHT
 - INCREASING SHOWER / THUNDERSTORM POTENTIAL WEDNESDAY - THURSDAY
 - PERHAPS A LULL IN THE WEATHER ON FRIDAY
 - LOOKING POTENTIALLY WET AND ACTIVE FOR NEXT WEEKEND

*/ DISCUSSION...

FORECAST GUIDANCE STRUGGLING WITH BOTH STRENGTH AND INFLUENCE OF
RIDGING ACROSS THE E-CONUS AND SUBSEQUENT ALLOWANCE OF N-STREAM
ENERGY TO SLIP S. AS BEEN THE TREND THE LAST SEVERAL DAYS...THE
RIDGE DEAMPLIFIES SUBSEQUENT TO THE FLATTENING MARITIME FLOW AND
RETROGRADING LOW PULLING COOLER AIR CYCLONICALLY SW. THERE IS NOT
MUCH SUPPORT IN MAINTAINING A RIDGING PATTERN. SO EXPECTATION THRU
THE WEEK IS FOR N-STREAM ENERGY TO HAVE THE ABILITY TO TROUGH S
SHIFTING THE CONVERGENT SW-FLOW ALONG WITH THETA-E / INSTABILITY
AXES INTO NEW ENGLAND. ANTICIPATING INCREASING CHANCES FOR SHOWERS
AND THUNDERSTORMS ESP ACROSS THE INTERIOR. SHEAR NOT IMPRESSIVE
COMPARED TO INSTABILITY...SO ECHO PRIOR FORECASTER WITH CONCERN OF
HEAVY RAIN AS A THREAT.

WILL KEEP TUESDAY INTO TUESDAY NIGHT DRY. THOUGH THE WARM AND MUGGY
CONDITIONS POTENTIALLY EXCEEDING CONVECTIVE-TEMPERATURES ACROSS THE
N AND W MAY YIELD THUNDERSTORMS THAT WOULD PUSH E WITH THE STEERING
FLOW...FEEL DRY AIR AND SUBSIDENCE WILL ERODE / WEAKEN ANY ACTIVITY
INTO NEW ENGLAND. THE BETTER FORCING AND SW-CONVERGENT FLOW OF MOIST-
INSTABILITY AXES IS WELL NW AT THIS TIME. LOW-90S POSSIBLE ACROSS
INTERIOR VALLEYS. EXPECT MARINE STRATUS / FOG ALONG THE S/SE-COAST
PERHAPS DEVELOPING AS EARLY AS MONDAY NIGHT INTO TUESDAY.

WEDNESDAY INTO THURSDAY THE RIDGE WEAKENS ALLOWING THE FAVORABLE
ENVIRONMENT FOR SHOWERS AND THUNDERSTORMS TO SHIFT SE. INCREASING
POP CHANCES ACCORDINGLY. SOME QUESTION AS TO HOW EFFECTIVELY WE CAN
DESTABILIZE. COULD BE ISSUES WITH CLOUD COVER SHOULD ACTIVITY ON
WEDNESDAY EXPECTED MAINLY W DRIFTS E OVERNIGHT INTO THURSDAY. WILL
CONTINUE WITH WARM AND MUGGY CONDITIONS. LOW-90S POSSIBLE ACROSS
INTERIOR VALLEYS ESPECIALLY WEDNESDAY. CONTINUED POTENTIAL OF MARINE
STRATUS / FOG ALONG THE S/SE-COAST.

FRIDAY COULD BE A LULL WITH DRY AIR AND HIGH PRESSURE IN PLACE IF
YOU BELIEVE THE GFS OVER THE ECMWF. LOW CONFIDENCE. CONSENSUS OF
FORECAST GUIDANCE HAS ANOTHER WAVE N PUSHING A FRONTAL BOUNDARY S
AND STALLING OVER NEW ENGLAND MAKING IT A FOCUS FOR A PROLONGED
PERIOD OF WET-WEATHER. HAVE SOME DOUBTS WITH CONVERGENT MASS-FIELDS
N AS SURFACE REFLECTIONS FOCUS S WITH THERMAL-INSTABILITY-MOIST
AXES. SHOULD HAVE A BETTER IDEA AS WE GET CLOSER IN TIME.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...

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

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

15Z UPDATE...
VFR WITH SW FLOW. 20-25 KT GUSTS INTO EARLY THIS EVENING...MAINLY
NEAR COASTAL TERMINALS. CIGS AOA 060 LATE TONIGHT AND MONDAY. LOW
PROB OF AN ISOLATED -SHRA/TSRA POSSIBLE ACROSS NW MA MONDAY.

KBOS TERMINAL...HIGH CONFIDENCE IN TAF.

KBDL TERMINAL...HIGH CONFIDENCE IN TAF.

OUTLOOK...MONDAY NIGHT THROUGH THURSDAY NIGHT...

MONDAY NIGHT INTO TUESDAY NIGHT...MODERATE CONFIDENCE. VFR. BREEZY
SW-FLOW WITH 20-25 KT GUSTS. IFR STRATUS / FOG POSSIBLE ACROSS THE
S/SE-COAST.

WEDNESDAY INTO THURSDAY NIGHT...MODERATE CONFIDENCE. INCREASING
CHANCES FOR -SHRA / TSRA. TEMPO MVFR-IFR WITH ANY ACTIVITY. SW-FLOW
WITH 20 KT GUSTS AT TIMES. IFR STRATUS / FOG REMAINS POSSIBLE ACROSS
THE S/SE-COAST.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

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

11 AM UPDATE...

NOTING SEVERAL REPORTS FROM THE FERRIES OUT TO THE ISLANDS OF
GUSTS TO AROUND 25 KT AND SEAS UP TO 5 FT...MAINLY ON BUZZARDS BAY
AND VINEYARD SOUND ON THE SW WIND. SEAS WILL ALSO BUILD TO AROUND
5 FT ON THE SOUTHERN OPEN WATERS MAINLY S OF NANTUCKET/MARTHAS
VINEYARD THIS AFTERNOON. SMALL CRAFT CONTINUES.

PREVIOUS DISCUSSION...
GUSTS MAY BE MARGINAL ALONG E MA COAST INCLUDING BOS HARBOR BUT
DECIDED TO INCLUDE THESE AREAS DUE TO INCREASE IN HOLIDAY
RECREATIONAL TRAFFIC.

WINDS AND SEAS DIMINISH TONIGHT. SW FLOW PERSISTS MON BUT GUSTS
ARE EXPECTED TO REMAIN BELOW SCA.

OUTLOOK...MONDAY NIGHT THROUGH THURSDAY NIGHT...

MODERATE CONFIDENCE. PERSISTENT SW-FETCH WITH GUSTS AROUND 20-25 KTS
AT TIMES. WAVE HEIGHTS IN EXCESS OF 5-FEET MOSTLY ON THE OUTER
WATERS BUT GETTING INTO THE S INNER SOUNDS. FOG ANTICIPATED LENDING
TO VISIBILITY RESTRICTIONS.

&&

.FIRE WEATHER...

11 AM UPDATE...
DEWPTS AWAY FROM THE S COAST ARE A BIT LOWER THAN FORECAST...DOWN
TO THE LOWER-MID 30S. WITH TEMPS IN THE LOWER-MID 70S...NOTING MIN
RH VALUES DOWN TO 15-25 PERCENT. HOWEVER...WINDS NOT QUITE AS
STRONG THERE AS ALONG THE COAST...NOTING GUSTS BELOW 20 KT THERE.
STILL HAVE SOME CONCERNS FOR ELEVATED FIRE WEATHER SPREAD THROUGH
THIS AFTERNOON. SPECIAL WEATHER STATEMENT REMAINS IN PLACE TO
ADDRESS THIS CONCERN.

PERSISTENT SW FLOW WILL BRING GRADUAL INCREASE IN HUMIDITY THIS
WEEK.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR
     ANZ230>237-250-251.
     SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR ANZ254>256.

&&

$$
SYNOPSIS...SIPPRELL/JWD
NEAR TERM...SIPPRELL/EVT
SHORT TERM...JWD
LONG TERM...SIPPRELL
AVIATION...SIPPRELL/JWD
MARINE...SIPPRELL/EVT
FIRE WEATHER...STAFF


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