Area Forecast Discussion
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000
FXUS61 KBOX 260814
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
414 AM EDT TUE MAY 26 2015

.SYNOPSIS...
WARM AND MUGGY CONDITIONS WILL INCREASE TODAY AND INTO TOMORROW.
SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED EACH DAY WITH
WEDNESDAY AND THURSDAY HAVING THE HIGHER POTENTIAL FOR STRONG
STORMS.

&&

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

4 AM UPDATE...

OVERALL TREND IN THE FORECAST REMAINS ON TRACK AS WARM FRONT
CONTINUES TO PUSH ACROSS NH AND MAINE. TEMPERATURES HAVE REMAINED
STEADY OVERNIGHT...IN THE MID 60S AWAY FROM THE SOUTH COAST.
SOUTHERLY WINDS CONTINUE TO GUST OCCASIONALLY THROUGH THE REST OF
THE MORNING.

TODAY...

BERMUDA HIGH CONTINUES TO BUILD UPPER LEVEL RIDGE ACROSS THE REGION
TODAY. DESCENT AMOUNT OF WARM AIR ADVECTION WILL KEEP CLOUDS AROUND
AS HIGH TEMPS WARM INTO THE MID TO UPPER 80S AWAY FROM THE SOUTH
COAST. GUSTY SOUTHWESTERLY WINDS WILL STREAM THE STABLE MARITIME
AIR ACROSS THE SOUTH COAST OF RI AND MASS...INCLUDING THE CAPE AND
ISLANDS KEEPING TEMPS INTO THE 70S.

OTHERWISE THE FOCUS IS TURNED TO THE POTENTIAL FOR SHOWERS AND
THUNDERSTORMS FOR TODAY. WEAK MID-LEVEL SHORTWAVE WILL PASS NORTH OF
THE REGION THIS AFTERNOON/EVENING WHICH COULD TRIGGER A FEW SHOWERS
AND/OR THUNDERSTORMS. HAVE A LOW CONFIDENCE AS TEMPS ALOFT REMAIN
WARM AND HEIGHTS DROP ONLY SLIGHTLY....LIMITING POTENTIAL AND
COVERAGE. HOWEVER WE DO HAVE PLENTY OF MOISTURE BUT INSTABILITY
WILL BE MARGINAL AS CLOUDS WILL LIMIT HEATING TODAY...YET WE STILL
COULD SEE CAPE VALUES NEAR 1000 J/KG. BELIEVE LOCATIONS WEST TO
THE REGION WILL SEE THE BULK OF THE ACTIVITY AS SOUTHERN NEW
ENGLAND MAY SEE JUST A FEW POP-UP SHOWERS. BEST LOCATIONS FOR THE
POTENTIAL WILL BE ACROSS NORTHERN CT AND WESTERN MASS.


&&

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

WARM...MUGGY CONDITIONS WILL CONTINUE OVERNIGHT AS SOUTHERLY FLOW
CONTINUE TO BRING IN HIGHER DEWPOINTS. THE POTENTIAL FOR FOG WILL BE
ON THE INCREASE ESPECIALLY ACROSS THE SOUTH COAST...CAPE AND THE
ISLAND AS 60F DEWPOINTS STREAM OVER THE COOLER OCEAN. IN FACT WE
COULD SEE LOCALLY DENSE FOG BUT BECAUSE OF THE UNCERTAINTY...HELD
OFF ON DENSE FOG ADVISORY.

ANY LEFT OVER CONVECTION ACROSS NEW YORK WILL HAVE THE POTENTIAL TO
MOVE OVER SOUTHERN NEW ENGLAND IN A WEAKEN STATE OVERNIGHT. SEVERAL
GUIDANCE MEMBERS SUGGEST THIS WILL OCCUR BUT SPLIT ON WHERE THIS
WILL OCCUR. THE NAM SAYS THE BULK OF THE SHOWERS WILL BE ACROSS THE
SOUTH COAST WHILE THE GFS/EC SHOWS THAT THE POTENTIAL WILL BE
ACROSS THE MASS PIKE. BECAUSE OF THE UNCERTAINTY KEPT SLIGHT CHC
ACROSS MUCH OF THE REGION.

TOMORROW...

WARM...MUGGY CONDITIONS CONTINUE INTO TOMORROW. SOUTHERLY FLOW WILL
BE A TAD STRONGER KEEPING TEMPS ALONG THE SOUTH COAST IN THE 70S
WHILE THE INTERIOR WARMS INTO THE MID 80S. SOUTHWESTERLY WIND GUSTS
WILL GUST BETWEEN 20-30 KTS.

COULD SEE LINGERING SHOWERS IN THE MORNING HOURS...BUT CLOUDS SHOULD
BREAK DURING THE AFTERNOON. UPPER LEVEL RIDGE SHOULD DOMINATE THE
REGION THROUGH MUCH OF THE DAY AS A COLD FRONT SLOWLY WORKS IT WAY
EASTWARD. FEEL WEDNESDAY HAS THE BETTER POTENTIAL TO SEE A FEW
STRONG THUNDERSTORMS WITHIN THE PRE-FRONTAL TROUGH AND MODEST
SOUTHERLY FLOW...ESPECIALLY ACROSS CT AND WESTERN MA. ASIDE FROM THE
ABUNDANT MOISTURE...CAPE VALUES WILL RANGE BETWEEN 1500-2000 J/KG
WITH ABOUT 25 KTS OF SHEAR. PWAT VALUES WILL BE ABOUT 1.6 INCHES
COMBINED WITH A DESCENT SOUTHERLY LLJ AND WARM CLOUD PROCESSES PER
BUFKIT SOUNDINGS...ANY THUNDERSTORM HAS THE POTENTIAL TO PRODUCE
VERY HEAVY RAIN. HAVE ADDED ENHANCED WORDING FOR HEAVY RAINFALL TO
THE FORECAST. COULD SEE SOME STRONG WINDS GUSTS BUT BELIEVE HEAVY
RAIN IS THE MAIN THREAT.

FOG WILL BEGIN TO REDEVELOP ALONG THE SOUTH COAST BY THE EVENING
HOURS LIMITING VISIBILITIES.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
OVERVIEW AND MODEL PREFERENCES...
OVERALL SURFACE AND UPPER LEVEL PATTERN LOOKING MORE AND MORE LIKE
SUMMER WITH H5 RIDGE BUILDING ACROSS EASTERN SEABOARD THROUGH
LATE THIS WEEK. WILL SEE WARM AND HUMID CONDITIONS INTO THIS
WEEKEND AT LEAST. MODELS AND ENSEMBLES THEN DIVERGE ON HOW QUICKLY
THIS RIDGE WILL BREAK DOWN...ALLOWING FRONTAL SYSTEMS TO TRY AND
PUSH S OUT OF QUEBEC AND NORTHERN NEW ENGLAND. WITH THESE FRONTS
MOVING INTO A NEARLY PARALLEL UPPER FLOW...WILL TEND TO SLOW DOWN
AND WEAKEN AS THEY SHIFT TOWARD THE REGION. WILL SEE SOME RELIEF
TO THE EXTENDED DRY CONDITIONS ESPECIALLY DURING THE WED-FRI
TIMEFRAME WHEN BEST SHOT FOR DEEP MOISTURE PLUME MOVING NE OUT OF
THE CENTRAL U.S...WHERE THE RECORD FLOODING RAINS HAVE BEEN
OCCURRING OVER THE LAST FEW WEEKS. TIMING ISSUES COME INTO PLAY
THIS WEEKEND AS ANOTHER FRONT TRIES TO APPROACH AND WHETHER IT
WILL MOVE OFFSHORE OR SLOW DOWN ACROSS THE REGION.

LEANED TOWARD AVAILABLE GUIDANCE THROUGH THE REMAINDER OF THE WORK
WEEK...THEN TRANSITIONED OVER TO THE 00Z ECMWF AND ECENS MEANS
WHICH WERE SLOWER IN BRINGING THE WEEKEND FRONT INTO THE REGION AS
ONE WOULD EXPECT WITH HOW MODELS HANDLE LONG WAVE PATTERN
TRANSITIONS.

DETAILS...

WEDNESDAY...H5 RIDGING SHIFTS E DURING WED WITH SW WIND FLOW AT
SURFACE AND ALOFT IN PLACE. WILL SEE FIRST IN SERIES OF COLD
FRONTS WILL SLOWLY PUSH SE TOWARD THE REGION. GOOD INSTABILITY OUT
AHEAD OF THIS FRONT. MODEL CAPES RISING TO AROUND 1000 J/KG /NAM
IS HIGHER/...K INDICES RISING TO THE LOWER-MID 30S AND LI/S
FALLING BELOW ZERO. LOWEST PARAMETERS LOOK TO MOVE INTO CENTRAL
AND WESTERN AREAS DURING THE AFTERNOON AND CONTINUE THROUGH WED
NIGHT. ALSO NOTING INCREASING PWATS...UP TO 1.8 TO 1.9
INCHES...SO COULD SEE SOME DOWNPOURS WITH ANY CONVECTION.

HAVE CHANCE POPS GOING...WITH HIGHEST FROM NE...CENTRAL AND
WESTERN MASS INTO N CENTRAL CT WHERE BEST SHOT FOR ANY STRONG OR
EVEN POSSIBLY SEVERE STORMS COULD OCCUR. SPC HAS MARGINAL SHOT FOR
SEVERE STORMS IN THESE AREAS. EXPECT HIGHS IN THE 80S...WITH A
COUPLE OF SPOTS APPROACHING 90 WELL INLAND.

MAY SEE AREAS OF FOG...WHICH COULD BE LOCALLY DENSE ALONG THE
IMMEDIATE S AND SE COASTS...DEVELOP DURING WED NIGHT AS DEWPTS
CONTINUE TO SLOWLY RISE.

THURSDAY...FRONTAL BOUNDARY WASHES OUT BUT STILL SOME INSTABILITY
LINGERING WITH SOUPY AIRMASS ACROSS THE REGION. INSTABILITY
PARAMETERS NOT QUITE AS STRONG AS ON WED BUT STILL DECENT SO COULD
SEE A FEW STRONG STORMS AS MID LAYER STARTS TO COOL A BIT LENDING
TO ELEVATED INSTABILITY. SOMEWHAT LOWER PWATS...AROUND 1.5 INCHES
BUT STILL ENOUGH WITH THE HIGH DEWPTS FOR HEAVY RAINFALL FROM ANY
CONVECTION. EXPECT AREAS OF FOG TO REDEVELOP ALONG S COASTAL AREAS
THU NIGHT INTO FRI MORNING.

FRIDAY...WHILE ANOTHER BOUNDARY TENDS TO WEAKEN OVER THE REGION...
NOT A WHOLE LOT OF FORCING IN BETWEEN SYSTEMS DURING THIS
TIMEFRAME. ALSO NOTING SOMEWHAT DRIER AIR ALOFT WHICH DOES NOT
HELP IN DEVELOPING CONVECTION. HOWEVER...STILL CAN NOT RULE OUT
CHANCE FOR DIURNAL SHOWERS/TSTMS TO DEVELOP MAINLY FROM NE MASS
ACROSS CENTRAL AND WESTERN AREAS INTO N CENTRAL CT WITH DEWPTS IN
THE 60S. ONE MORE ROUND OF FOG LOOKS TO DEVELOP ALONG THE COAST
MAINLY FROM COASTAL PLYMOUTH COUNTY SOUTHWARD.

SATURDAY...MODELS BEGIN TO DIVERGE ON THEIR SOLUTIONS AS ANOTHER
FRONT TRIES TO SLIP SE OUT OF SOUTHERN QUEBEC. LOOKS LIKE MORE
DIURNAL SHOWERS/TSTMS DURING THE AFTERNOON/EVENING ACROSS INLAND
AREAS.

SUNDAY-MONDAY...TIMING DIFFERENCES WITH THE APPROACHING FRONT LEND
TO LOW CONFIDENCE DURING THIS TIMEFRAME. WENT WITH THE SLOWER
ECMWF GUIDANCE...WHICH TENDS TO BE THE CASE WITH UPPER LEVEL
BLOCKING PATTERNS TRYING TO BREAK DOWN. IN ANY EVENT...HAVE MORE
CHANCES FOR SHOWERS/THUNDERSTORMS FOR SUNDAY AS THE FRONT LOOKS TO
SLOWLY PUSH ACROSS THE REGION...THEN STALLING NEAR OR JUST OFF THE
S COAST ON MONDAY WITH LOWER CHANCE FOR SHOWERS. MAY SEE DRIER AIR
WORK INTO N MA DURING MON AFTERNOON...BUT AGAIN LOW CONFIDENCE ON
THIS TIMING.

&&

.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /THROUGH WEDNESDAY/...HIGH CONFIDENCE.

BEFORE 12Z...VFR. SOUTHWEST GUSTS BETWEEN 15-20 KTS ACROSS THE
CAPE OVERNIGHT.

TODAY...VFR. CHANCE OF A TSTM WITH MVFR VSBYS/CIGS ACROSS
CT/PIONEER VALLEY THIS AFTERNOON. IFR STRATUS AND FOG WILL
INCREASE ACROSS SOUTH COAST LATE AFTERNOON/EVENING.

TONIGHT...VFR DETERIORATING TO MVFR/IFR IN AREAS OF FOG
PARTICULARLY ALONG THE SOUTH COAST...CAPE...AND ISLANDS. COULD SEE
PASSING SHOWER/TSTORM OVERNIGHT.

WEDNESDAY...IFR ALONG THE SOUTH COAST DURING THE MORNING SHOULD
PUSH OFFSHORE. ANTICIPATE VFR CONDITIONS ACROSS THE
INTERIOR...DROPPING TO MVFR WITHIN ANY -SHRA/-TSRA THAT DEVELOPS.
EXPECT SW WINDS TO GUST UP TO 20-25 KT AT TIMES MAINLY ACROSS
RI/SE MA WED AFTERNOON/EVENING.

KBOS TERMINAL...HIGH CONFIDENCE IN TAF.

KBDL TERMINAL...HIGH CONFIDENCE IN TAF. COULD SEE CONDITIONS DROP
TO MVFR WITHIN A POP-UP THUNDERSTORM TODAY.

OUTLOOK...WEDNESDAY NIGHT THROUGH SATURDAY...MODERATE CONFIDENCE.

WEDNESDAY NIGHT...AREAS OF FOG DEVELOP WED NIGHT WITH MVFR-IFR
VSBYS. MAY SEE PATCHY LIFR CIGS/VSBYS WITH OCEAN CLOUDS/DENSE FOG
ALONG THE IMMEDIATE S AND SE COASTS OVERNIGHT.

THURSDAY AND FRIDAY...EXPECT CHANCE FOR -SHRA/TSRA WITH LOCAL
MVFR-IFR CONDITIONS. WILL ALSO SEE AREAS OF FOG DEVELOP EACH LATE
NIGHT/EARLY MORNING PERIOD WITH IFR-LIFR VSBYS.

SATURDAY...PATCHY FOG EARLY SAT MORNING WITH MVFR-IFR CONDITIONS
WILL IMPROVE. SCT SHRA/TSRA SAT THROUGH SAT NIGHT WITH LOCAL
MVFR-IFR CONDITIONS.

SUNDAY...S-SW WINDS WILL GUST UP TO 25 KT AT TIMES SAT AFTERNOON/
EVENING...MAINLY ALONG THE S COAST...CAPE COD AND THE ISLANDS.
SCT SHOWERS/ISOLD TSTMS MAY LINGERING THROUGH SUNDAY...BUT SHOULD
END SUN NIGHT. MAY SEE BRIEF MVFR CONDITIONS.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /THROUGH WEDNESDAY/...HIGH CONFIDENCE.

SOUTHWESTERLY FLOW WILL CONTINUE THROUGH THE PERIOD. THIS WILL
HELP BUILD SEAS AND SWELL ACROSS THE SOUTHERN WATERS BY TONIGHT
AND TOMORROW. OTHERWISE EXPANDED THE SCA FOR NEAR SHORE WATERS AS
GUSTS WILL REACH 25KTS DURING THIS AFTERNOON. IN ADDITION...AREAS
OF FOG ARE LIKELY TO DEVELOP TONIGHT...REDUCING VISIBILITIES.

OUTLOOK...WEDNESDAY NIGHT THROUGH SATURDAY...MODERATE CONFIDENCE.


THURSDAY THROUGH SATURDAY...S-SW WINDS REMAIN PERSISTENT WITH
GUSTS UP TO AROUND 20 KT MAINLY THU INTO THU NIGHT. SEAS LINGERING
AT AROUND 5 FT ACROSS THE SOUTHERN OPEN WATERS THROUGH THU THEN
SHOULD SUBSIDE. VSBYS REDUCED IN AREAS OF FOG...LOCALLY DENSE
OFFSHORE BOTH THU AND FRI NIGHTS.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT WEDNESDAY FOR ANZ235-250-
     254>256.

&&

$$
SYNOPSIS...DUNTEN/EVT
NEAR TERM...DUNTEN
SHORT TERM...DUNTEN
LONG TERM...EVT
AVIATION...DUNTEN/EVT
MARINE...DUNTEN/EVT



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