Area Forecast Discussion
Issued by NWS Boston, MA

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000
FXUS61 KBOX 290531
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
131 AM EDT FRI MAY 29 2015

.SYNOPSIS...
ANY LEFTOVER SHOWERS WILL COME TO AN END THIS EVENING AS THE COLD
FRONT SLOWS DOWN NEAR THE SOUTH COAST OVERNIGHT. ON FRIDAY...HIGH
PRESSURE WILL BRING DRY CONDITIONS. ANOTHER COLD FRONT WILL SLOWLY
MOVE ACROSS THE REGION THIS WEEKEND...BRINGING A GREATER CHANCE
FOR SHOWERS AND SOME SCATTERED THUNDERSTORMS. THIS FRONT MAY
LINGER NEAR OUR AREA INTO THE BEGINNING OF THE NEXT WEEK...WITH
HIGH PRESSURE RETURNING BY MIDWEEK.

&&

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

200 AM UPDATE...

COLD FRONT IS NOW SITUATED ACROSS KSNC THROUGH KPVD INTO KPVC.
THIS FRONT IS STILL SLOW GOING AND WILL EVENTUALLY BECOME WASHED
OUT OVERNIGHT. AHEAD OF THE FRONT SIGNIFICANT POOLING OF MOISTURE
HAS ALLOWED FOR FOG AND LOW CLOUDS TO DEVELOP ACROSS THE SOUTH
COAST...CAPE AND ISLANDS. VSBYS WILL DROP BETWEEN 2-5 MILES...LOW
CONFIDENCE ON DENSE FOG.

OTHERWISE DRY AIR CONTINUES TO FILTER IN ACROSS THE REGION AS
DEWPOINTS CONTINUE TO DROP INTO THE MID TO LOW 50S. WHERE RAIN
OCCURRED...AND DRY AIR MOVING IN ALOFT COULD SEE SOME FOG DEVELOP
ACROSS VALLEY REGIONS THANKS A MOIST LOW LEVEL INVERSION.



&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SATURDAY/...
TOMORROW...
WEAK RIDGE OF HIGH PRES WILL GRADUALLY CREST OVER THE REGION
THROUGH THE DAYLIGHT HOURS. WINDS WILL BE LIGHT...BUT GRADUALLY
SHIFTING BACK TO THE S...FROM THE NW THROUGH THE DAY. GIVEN THE
LIGHT WINDS...EXPECT LOCAL SEA BREEZES TO LIMIT DIURNAL TEMP
TRENDS NEAR THE COASTLINES. INLAND HOWEVER...WITH SOME
DOWNSLOPING...CT VALLEY LOCATIONS WILL MAKE A RUN AT THE MID 80S.
MAINLY UPPER 70S ELSEWHERE AWAY FROM THE COAST.

TOMORROW NIGHT...
ALTHOUGH SFC HIGH PRES CENTER WILL BE SHIFTING TO WELL S OF NOVA
SCOTIA...UPPER LVL RIDGE WILL CONTINUE TO BUILD THANKS TO STEADY
WARM ADVECTION UPSTREAM. THIS WILL KEEP ANY ACTIVITY ASSOCIATED
WITH ANOTHER SLOW MOVING COLD FRONT...WELL TO THE W. EXPECT ONLY
INCREASING HIGH CLOUDS ACROSS THE W OVERNIGHT. THE ONLY CAVEAT MAY
BE NEAR S COASTAL REGIONS...WHERE SLY FLOW AND SLIGHT INCREASE IN
DWPTS COULD PROMOTE DEVELOPMENT OF SOME LOCALIZED MARINE FOG AND
STRATUS ONCE AGAIN. THIS RISE IN DWPTS WILL ALSO KEEP MINS UP A
BIT...MAINLY DIPPING INTO THE UPPER 50S IN THE COOLEST SPOTS.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
OVERVIEW AND MODEL PREFERENCES...

OVERALL UPPER LEVEL RIDGING ALONG EASTERN SEABOARD APPEARS TO
BREAK DOWN SATURDAY...THEN TROUGH OUT OF CENTRAL CANADA BEGINS TO
SHIFT E LATE THIS WEEKEND INTO EARLY NEXT WEEK. ASSOCIATED COLD
FRONT WILL BE SLOW TO CLEAR THE REGION AS IT RUNS PARALLEL TO THE
UPPER FLOW. TIMING ISSUES COME IN PLAY FROM MONDAY ONWARD...
DEPENDING UPON HOW FAR S THE FRONT FINALLY SETTLES WHILE HIGH
PRES BUILDS OUT OF SOUTHERN ONTARIO AND THE GREAT LAKES EASTWARD.

LEANED TOWARD THE AVAILABLE GUIDANCE EARLY IN THIS PERIOD THEN
TRANSITIONED OVER THE GEFS AND ECENS GUIDANCE WHICH SHOWED A BIT
BETTER CONTINUITY.

DETAILS...

SATURDAY...HIGH PRES OFF THE EASTERN SEABOARD PUSHES FURTHER
OFFSHORE DURING THIS TIMEFRAME...WITH GOOD SW WIND FLOW AND
INCREASING HUMIDITY MOVING NE INTO THE REGION. MODELS TENDING TO
SLOW THE PROGRESS OF THE APPROACHING FRONT OUT OF WESTERN QUEBEC
AS THE UPPER RIDGE SLOWLY BREAKS DOWN AND SHIFTS E. HAVE MENTION
OF CHANCE POPS MOVING INTO WESTERN AREAS DURING SAT AFTERNOON...
THEN SHOULD PUSH SLOWLY SE SAT NIGHT.

GOOD INSTABILITY WITH THIS FRONT AS K INDICES INCREASE TO THE
LOWER-MID 30S. HAVE MENTIONED CHANCE POPS...BUT MENTIONED ONLY
SLIGHT CHANCE OF THUNDERSTORMS SAT NIGHT. NOTING INCREASING PWATS
ALONG AND AHEAD OF THIS FRONT AS WELL...UP TO 1.7 INCHES DURING
SAT NIGHT SO COULD SEE SOME LOCALLY HEAVY DOWNPOURS WITH ANY
ACTIVITY. WILL SEE HIGH TEMPS REACH AROUND 80 INLAND...BUT ONLY IN
THE UPPER 60S TO LOWER 70S ALONG THE IMMEDIATE S COAST. MAY SEE
SW WINDS GUSTING UP TO AROUND 25-30 MPH ACROSS RI/SE MA SAT
AFTERNOON/NIGHT.

SUNDAY...LOOKS LIKE BEST SHOT OF MOISTURE MOVES ACROSS THE
REGION SUN/SUN NIGHT. CARRYING CAT POPS NEAR/ALONG THE SLOWLY
MOVING FRONT...AS WELL AS SOME SCT THUNDERSTORMS. PWATS INCREASE
TO 1.7 TO 1.8 INCHES...SO COULD ALSO SEE SOME HEAVY DOWNPOURS.
AT THIS POINT...THINK THE FRONT WILL PUSH NEAR OR S OF THE MASS
PIKE AROUND SUN NIGHT...BUT WILL TEND TO SLOW DOWN ACROSS SOUTHERN
AREAS OVERNIGHT. THIS WILL LOWER THE CHANCE FOR THUNDERSTORMS AS
MORE STABLE AIR MOVES INTO N MA SUN NIGHT...BUT STILL COULD SEE
SPOTTY CONVECTION ACROSS N CT/RI/SE MA. HAVE KEPT LIKELY POPS
GOING THROUGH AROUND 06Z...THEN SLOWLY LOWER ACROSS CENTRAL AND
NORTHERN AREAS AFTER THAT. PRECIP LOOKS TO TAPER OFF ACROSS THE
ROUTE 2 AREA BY AROUND SUNRISE MON...BUT TIMING IS STILL IN
QUESTION.

MONDAY...A LOT OF UNCERTAINTY CONTINUES AS MOVING THE FRONT ACROSS
THE REGION...WITH TIMING DIFFERENCES AMONGST THE MODEL SUITE.
LOOKS LIKE THE CHANCE FOR PRECIP LINGERS THROUGH MON AND EVEN INTO
MON NIGHT...WITH THE BEST CHANCE ACROSS N CT/RI/SE MA. WINDS DO
START TO SHIFT AROUND TO N-NE ACROSS CENTRAL AND N MA SO THIS WILL
CUT BACK ON THUNDERSTORM ACTIVITY AS COOLER AIR MOVES IN. FOR
NOW...TEND TO TAPER OFF PRECIP BY MON NIGHT ACROSS MOST
AREAS...BUT DO LINGER IT ALONG THE S COAST THROUGH AT LEAST
MIDNIGHT MON NIGHT. IT WILL BE MUCH COOLER WITH HIGHS ONLY IN THE
60S...AND MAY NOT EVEN BREAK 60 ALONG THE E COAST WITH ONSHORE
WINDS.

TUESDAY-WEDNESDAY...PRECIP SHOULD FINALLY PUSH OFF THE S COAST BY
AROUND MIDDAY TUE AT THE LATEST. NE WINDS PICK UP AS HIGH PRES
CROSSES NORTHERN NEW ENGLAND DURING THIS TIMEFRAME. HAVE CARRIED A
DRY AND SEASONABLE FORECAST ON WEDNESDAY.

&&

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

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

BEFORE 12Z...HIGH CONFIDENCE. COLD FRONT WILL SWEEP THROUGH
OVERNIGHT. AHEAD OF FRONT COULD SEE IFR/MVFR STRATUS AND FOG. ALSO
COULD SEE MVFR FOG DEVELOP ACROSS CT VALLEY SITES.

TODAY AND TONIGHT...HIGH CONFIDENCE. MAINLY VFR. EXPECT SEA
BREEZES WITH WINDS SHIFTING MAINLY TO THE E LATE IN THE DAY. SOME
PATCHY MVFR CIGS COULD DEVELOP ALONG SOUTH COAST TONIGHT.

SATURDAY...MODERATE CONFIDENCE. MAINLY VFR THROUGH THE DAY. MVFR
CIGS COULD DEVELOP WITHIN -SHRA/-TSRA ACROSS CT VALLEY REGION.

KBOS TERMINAL...HIGH CONFIDENCE IN TAF. SEA BREEZE WILL DEVELOP
BETWEEN 13-15Z.

KBDL TERMINAL...HIGH CONFIDENCE IN TAF.

OUTLOOK...SUNDAY THROUGH TUESDAY...MODERATE CONFIDENCE.

SUNDAY...NUMEROUS SHOWERS WITH SCATTERED TSTMS POSSIBLE DURING
THE DAY WITH LOCAL MVFR CONDITIONS. LIGHT WINDS SHIFT TO N-NE
DURING THE DAY...THEN BECOME NE SUN NIGHT WHICH MAY GUST UP TO
AROUND 20 KT ALONG THE S COAST. SHOWERS LINGER SUNDAY NIGHT.

MONDAY...SCT SHOWERS LINGERING WITH LOCAL MVFR CONDITIONS EARLY
BUT WILL IMPROVE FROM N-S DURING THE DAY EXCEPT ALONG THE S COAST
WHERE SHOWERS WILL HANG IN THROUGH SUN NIGHT. MAY SEE BRIEF MVFR
IN ANY SHOWERS THERE SUN NIGHT. NE WINDS GUSTING TO 20-25 ACROSS
OUTER CAPE COD AND THE ISLANDS.

TUESDAY...MAINLY VFR CONDITIONS. MAY SEE ISOLD SHOWERS EARLY TUE
ALONG S COAST BUT SHOULD MOVE OFFSHORE. NE WIND GUSTS TO 25 KT
STILL POSSIBLE ACROSS THE OUTER CAPE AND ISLANDS.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...

TONIGHT...HIGH CONFIDENCE.
GUSTY WINDS OVERNIGHT HAVE DROPPED OFF AND SEAS ARE BELOW 5FT.
HAVE DROPPED THE SCA.

FRIDAY AND FRIDAY NIGHT...HIGH CONFIDENCE.
HIGH PRES BUILDS OVER THE WATERS. MAINLY QUIET BOATING WEATHER
EXPECTED ALTHOUGH SOME STRATUS/FOG IS POSSIBLE MAINLY ON THE SRN
WATERS TOMORROW NIGHT.

OUTLOOK...SATURDAY THROUGH TUESDAY...MODERATE CONFIDENCE.

SATURDAY...SW WINDS WILL LIKELY GUST UP TO 25 KT ACROSS THE
EASTERN OUTER WATERS...AND POSSIBLY ON THE NEAR SHORE WATERS SAT
AFTERNOON. SEAS BUILD TO AROUND 5 FT ON ALL THE OUTER WATERS...
POSSIBLY INTO RI AND BLOCK ISLAND SOUNDS. WINDS SHOULD DIMINISH
DURING SAT NIGHT. VSBY RESTRICTIONS IN PATCHY FOG ALONG S COASTAL
WATERS EARLY...THEN SHOULD IMPROVE.

SUNDAY...COLD FRONT SLOWLY CROSSES THE WATERS. MAY SEE BRIEF
GUSTS TO 25 KT AS FRONT PASSES DURING SUNDAY...THEN WILL STALL
NEAR OR JUST S OF THE S COAST SUN NIGHT. WINDS SHIFT TO E-NE AS
FRONT PASSES. AREAS OF SHOWERS WITH SCT THUNDERSTORMS. LOCAL VSBY
RESTRICTIONS.

MONDAY-TUESDAY...EXPECT MAINLY NE WINDS. GUSTS TO 25 KT ACROSS
THE SOUTHERN OPEN WATERS AS THE FRONT SLOWLY MOVES OFFSHORE.
SEAS BUILD UP TO 6-8 FT ON THE SOUTHERN OUTER WATERS TO E OF
CAPE COD...AND UP TO 5 FT ON THE EASTERN OUTER WATERS. MAY SEE
LINGERING SHOWERS DURING MONDAY ACROSS THE SOUTHERN WATERS.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

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


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