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348
FXUS61 KBOX 010740
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
340 AM EDT MON SEP 1 2014

.SYNOPSIS...
A WARM HUMID FLOW WILL CONTINUE ACROSS NEW ENGLAND THROUGH
TUESDAY WITH SCATTERED SHOWERS AND THUNDERSTORMS EACH DAY. A COLD
FRONT WILL MOVE THROUGH TUESDAY NIGHT. LESS HUMID WEATHER WILL
THEN FOLLOW FOR WEDNESDAY THROUGH FRIDAY. ANOTHER COLD FRONT MAY
BRING A CHANCE OF SHOWERS AND THUNDERSTORMS NEXT SATURDAY.

&&

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

THROUGH 8 AM...
WARM HUMID AIR IN PLACE OVER SOUTHERN NEW ENGLAND WITH LIGHT
SOUTHWEST WIND FLOW. THIS WILL SUPPORT AREAS OF FOG THROUGH
SUNRISE. THE BEST CHANCE FOR FOG WILL BE ALONG THE SOUTH COAST OF
RI AND MASS...AS WELL AS IN THE CT RIVER VALLEY. TEMPERATURES WILL
HOLD IN THE UPPER 60S AND LOWER 70S.

AN AREA OF SHOWERS/TSTMS PASSING SOUTH OF LONG ISLAND SHOULD PASS
SOUTH OF THE ISLANDS TOWARD SUNRISE. THERE IS A LOW CHANCE THAT
THE SHOWERS COULD CLIP NANTUCKET.

TODAY...
WARM HUMID AIR WITH DEWPOINTS IN THE UPPER 60S AND 70S. A FRONT
IS STALLED ALONG THE CANADIAN BORDER. MEANWHILE A LEE TROUGH WILL
BE POSITIONED NEAR THE MID ATLANTIC COAST. BOTH OF THESE WILL
SERVE AS FOCII FOR THUNDERSTORM DEVELOPMENT.

SOMEWHAT DRIER AIR MOVES INTO NORTHERN NEW ENGLAND WITH PRECIP
WATER VALUES NEAR 1 INCH. MEANWHILE 2 INCH VALUES LINGER ALONG THE
SOUTH COAST. THIS MOISTURE WILL BE THE POTENTIAL FUEL FOR ANY
DAYTIME CONVECTION. STABILITY PARAMETERS LOOK FAVORABLE FOR TSTMS
BUT LIKELY NOT AT SEVERE LEVELS. TOTALS START LOW AND CLIMB TO
46-47 IN THE AFTERNOON WITH HIGHEST VALUES ACROSS CT-RI-SE MASS.
THE GFS SHOWS SHOWS SBCAPE REACHING 1000-1500 J/KG ESPECIALLY IN
CT. LOW LEVEL HELICITY IS MUCH LOWER THAN SUNDAY...20-30 M2/S2.
POPS WILL FAVOR AFTERNOON/EVENING TSTMS WITH HIGHEST VALUES AT THE
SOUTH COAST. WITH PRECIP WATER VALUES AT 1.5-2.0 INCHES SOUTH OF
THE MASS PIKE...ANY STORMS IN THIS AREA WILL HAVE POTENTIAL FOR
HEAVY DOWNPOURS AND POSSIBLE URBAN/POOR DRAINAGE FLOODING.
MAX SFC TEMPS WILL AGAIN BE IN THE MID 80S.

&&

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

TONIGHT...
LINGERING CONVECTION IN THE EVENING BUT DIMINISHING. HIGH HUMIDITY
AND LIGHT WIND WILL AGAIN FAVOR DEVELOPMENT OF FOG OVERNIGHT.
MIN SFC TEMPS WILL BE NEAR THE DEW POINTS...MAINLY UPPER 60S AND
LOWER 70S.

TUESDAY...
UPPER SHORTWAVE DIGS OVER THE GREAT LAKES WHILE HIGH PRESSURE
REMAINS TO OUR EAST. THIS WILL MAINTAIN THE WARM MOIST SOUTHWEST
FLOW ACROSS NEW ENGLAND. A COLD FRONT ASSOCIATED WITH THE UPPER
SHORTWAVE WILL MOVE EAST THROUGH THE EASTERN GREAT LAKES TO
EASTERN NEW YORK BY EVENING. A PRE-FRONTAL TROUGH WILL REMAIN OVER
THE HUDSON AND DELAWARE VALLEYS. FAVORABLE JET DYNAMICS REMAIN
WELL TO OUR WEST MUCH OF THE DAY...BUT APPROACH WESTERN
MASS/SOUTHERN NH LATE. TOTALS ON THE GFS ARE 50-51 WHILE THE
ECMWF AND GGEM ARE 47-48. MID LEVEL LAPSE RATES ARE AROUND 6C/KM.
SBCAPES ARE 500-1000 J/KG BY THE GFS HINTS AT 1000-1500 J/KG.
OVERALL WE WILL FAVOR CHANCE POPS FOR SHOWERS/TSTMS IN THE
AFTERNOON WITH THE BEST CHANCE IN WESTERN MASS/SOUTHERN NH AND
DIMINISHING VALUES FARTHER EAST. PRECIPITABLE WATER VALUES START
AROUND 1.5 INCHES AND CLIMB TO NEAR 2 INCHES...SO LOCALLY HEAVY
DOWNPOURS WILL AGAIN BE A CONCERN.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
OVERVIEW AND MODEL PREFERENCES...

BROAD RIDGING REMAINS THE DOMINATE FEATURE ACROSS THE EASTERN USA
THROUGH MOST OF THIS FORECAST PERIOD. THIS IS MORE TYPICAL FOR THE
MIDDLE OF SUMMER RATHER THAN EARLY SEPTEMBER. EARLY IN THIS
PERIOD...THERE WILL BE A COUPLE OF FAST MOVING SYSTEMS IN THE BROAD
NORTHERN STREAM THAT WILL AFFECT OUR REGION. THIS STRONG RIDGE
FINALLY BECOMES ESTABLISHED AROUND MID WEEK ACROSS THE SOUTHERN
USA...WITH WARM BUT DRY CONDITIONS THROUGH THE END OF THIS WEEK.
SOME QUESTIONS AS TO WHEN THE RIDGING MAY BREAK DOWN...AS MODEL
SOLUTIONS LATE IN THE RUN TRY TO BREAK DOWN THE RIDGE WHILE BRINGING
A MID-LEVEL CUTOFF LOW ACROSS NORTH CENTRAL CANADA INTO NORTHERN
QUEBEC.

OVERALL...HAVE FAIRLY GOOD CONFIDENCE WITH MOST OF THIS FORECAST...
THOUGH SOME QUESTIONS WITH POSSIBLE CHANGES IN THE STEERING PATTERN
OVER THE NORTHERN TIER LATE THIS WEEK. HAVE LEANED TOWARD A BLEND OF
AVAILABLE GUIDANCE INTO FRIDAY...THEN PUSHED TOWARD A BLEND OF THE
ECENS AND GEFS MEANS WHICH SHOWED A SLOWER BREAKDOWN OF THE RIDGING
ACROSS THE REGION...WITH LOWER CONFIDENCE IN THE DETAILS OF
THIS FORECAST FOR THIS WEEKEND.

DAILIES...

WEDNESDAY...EXPECTING DRIER AIR TO SLOWLY ARRIVE DURING THE DAY
ON LIGHT WEST WINDS. HIGH PRESSURE WILL BUILD OUT OF THE
APPALACHIANS. TEMPERATURES WILL REMAIN WARM FOR THIS TIME OF
YEAR...WITH A GENERAL WEST WIND FLOW THROUGHOUT THE LAYER. COULD
SEE SOME SHOWERS LINGER ACROSS CAPE COD AND THE ISLANDS DURING THE
EARLY MORNING HOURS.

THURSDAY AND FRIDAY...EXPECTING DRY AND MILD CONDITIONS CONTINUING
WITH DEWPOINTS FALLING INTO THE 50S...THOUGH AROUND 60 ALONG THE
IMMEDIATE COAST. CENTER OF HIGH PRESSURE SHIFTS OFFSHORE...RESULTING
AND LIGHT SOUTHWEST WINDS.  THIS SHOULD MEAN SLIGHT ABOVE NORMAL
TEMPERATURES AWAY FROM THE IMMEDIATE COASTS.

SATURDAY AND SUNDAY...LOTS OF QUESTIONS DURING THIS TIMEFRAME...
MAINLY DUE TO TIMING ISSUES OF A COLD FRONT. KEPT MENTION OF CHANCE
POPS AS A COLD FRONT TRIES TO CROSS SOUTHERN NEW ENGLAND THIS
WEEKEND. LOW CONFIDENCE WITH THIS FEATURE. HIGH PRESSURE SHOULD
EVENTUALLY RETURN LATER SUNDAY.

&&

.AVIATION /07Z MONDAY THROUGH FRIDAY/...
FORECASTER CONFIDENCE LEVELS...

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

SHORT TERM /THROUGH MONDAY NIGHT/...HIGH CONFIDENCE IN TRENDS BUT
LOWER CONFIDENCE IN PRECISE DETAILS AND TIMING.

OVERNIGHT...AREAS OF IFR IN FOG AND STRATUS OVERNIGHT. BEST CHANCE
FOR THIS WILL BE ALONG THE SOUTH COAST AND ISLANDS...AND ALONG
CAPE COD BAY. ALSO A GOOD CHANCE FOR IFR/LIFR IN THE CT RIVER
VALLEY.

TODAY...IFR CIGS MAY LINGER ALONG THE SOUTH COAST THROUGH MOST OF
THE DAY. NORTH OF THERE CONDITIONS IMPROVE TO VFR. ANOTHER
DISTUBANCE PASSES SOUTH OF NEW ENGLAND BUT MAY GENERATE ANOTHER
ROUND OF SHOWERS/TSTMS ACROSS CT/RI/SE MASS THIS
AFTERNOON/EVENING WITH LOCALLY HEAVY DOWNPOURS POSSIBLE. BRIEF
MVFR/IFR IN ANY TSTMS.

TONIGHT...EVENING SHOWERS/TSTMS ESPECIALLY OVER THE CAPE AND
ISLANDS. BRIEF MVFR/IFR IN ANY STORMS. QUIET WEATHER THE REMAINDER
OF THE NIGHT WITH AREAS OF IFR/LIFR IN STRATUS AND FOG. BEST CHANCE
WILL AGAIN BE ALONG THE SOUTH COAST AND ISLANDS AS WELL AS THE CT
RIVER VALLEY.

TUESDAY...MORNING FOG AND LOW CONDITIONS BURN OFF. VFR THROUGH
MUCH OF THE DAY. INCREASING CLOUDS FROM THE WEST DURING THE
AFTERNOON/EVENING WITH POTENTIAL FOR BRIEF MVFR IN SCATTERED
THUNDERSTORMS.

KBOS TERMINAL...HIGH CONFIDENCE IN TAF REGARDING TRENDS BUT LOWER
CONFIDENCE ON PRECISE DETAILS AND TIMING.

KBDL TERMINAL...HIGH CONFIDENCE IN TAF REGARDING TRENDS BUT LOWER
CONFIDENCE ON PRECISE DETAILS AND TIMING.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...

TUESDAY NIGHT...MODERATE CONFIDENCE.
PRECIP SHOULD TAPER OFF AFTER MIDNIGHT. PATCHY FOG RETURNS AFTER
05Z-06Z WITH MVFR-IFR VSBYS IN NORMALLY PRONE INLAND LOCATIONS.

WEDNESDAY THROUGH FRIDAY...MODERATE CONFIDENCE. EXPECTING MAINLY VFR
CONDITIONS AS HIGH PRESSURE BUILDS IN. LOCAL MVFR-IFR VSBYS AND CIGS
IN LATE NIGHT PATCHY FOG AND STRATUS. MAIN AREAS OF CONCERN WILL BE
THE TYPICALLY PRONE LOCATIONS ACROSS THE FAR INTERIOR /SOUTHWEST NH
AND NORTH CENTRAL AND WESTERN MA/.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

MODERATE CONFIDENCE THROUGH TUESDAY.

TODAY...
HIGH PRESSURE OFFSHORE AND LOW PRESSURE OVER THE GREAT LAKES WILL
MAINTAIN A SOUTHWEST WIND FLOW ACROSS THE WATERS THROUGH TUESDAY.
WINDS WILL REMAIN AT OR BELOW 20 KNOTS. SEAS WILL START AROUND 5
FEET ON THE OUTER WATERS BUT WILL DIMINISH THROUGH THE DAY. WE
HAVE MAINTAINED SMALL CRAFT ADVISORY ON THE SOUTHERN OUTER WATERS
THROUGH THE DAY DUE TO THE LINGERING ROUGH SEAS. A FEW
THUNDERSTORMS WILL MOVE ACROSS SOUTHERN NEW ENGLAND WITH THE BEST
CHANCE ON THE WATERS OCCURING SOUTH OF BOSTON.

TONIGHT...
EVENING THUNDERSTORMS DIMINISH EARLY AT NIGHT. LIGHT SOUTHWEST
FLOW WILL ALLOW AREAS OF FOG OVERNIGHT WITH POOR VISIBILITY.

TUESDAY...
AREAS OF FOG WILL START THE MORNING...WITH VISIBILITY IMPROVING
DURING THE MORNING. SHOWERS AND THUNDERSTORMS WILL MOVE INTO
WESTERN NEW ENGLAND DURING THE AFTERNOON AND MAY THREATEN THE
COASTAL WATERS TOWARD EVENING. TSTMS COULD CAUSE STRONG WIND
GUSTS...OTHERWISE EXPECT WINDS AND SEAS TO REMAIN BELOW SMALL
CRAFT LEVELS.

OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...

MODERATE CONFIDENCE. EXPECTING WINDS AND SEAS TO REMAIN BELOW SMALL
CRAFT CRITERIA THROUGH THIS PERIOD. MAY SEE SOME SOUTHWEST WIND
GUSTS UP TO 20 KT TUE NIGHT...BEFORE SHIFTING TO W-NW AND
DIMINISHING BY WED MORNING.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR
     ANZ254>256.

&&

$$
SYNOPSIS...WTB/KJC
NEAR TERM...WTB
SHORT TERM...WTB
LONG TERM...BELK
AVIATION...WTB/BELK
MARINE...WTB/BELK




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