Area Forecast Discussion
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000
FXUS61 KBOX 070919
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
519 AM EDT TUE JUL 7 2015

.SYNOPSIS...
A WARM FRONT WILL WEAKEN AS IT MOVES NORTH ACROSS THE REGION
TODAY. A COLD FRONT MOVES ACROSS THE REGION WEDNESDAY BRINGING
SHOWERS AND THUNDERSTORMS...SOME WITH HEAVY DOWNPOURS. THE FRONT
MOVES SOUTH OF NEW ENGLAND WEDNESDAY NIGHT AND STALLS...ALLOWING
ANOTHER ROUND OF SHOWERS AND STORMS THURSDAY. HIGH PRESSURE THEN
BUILDS IN WITH FAIR WEATHER FOR FRIDAY AND SATURDAY. ANOTHER
WEATHER SYSTEM APPROACHES EARLY NEXT WEEK AND MAY BRING MORE WET
WEATHER.

&&

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

PATCHY FOG HAS DEVELOPED SINCE 06Z ACROSS E MA AND ACROSS PORTIONS
OF THE ROUTE 2 CORRIDOR OF N MA...THOUGH LOWEST VSBYS NOTED HAVE
BEEN DOWN TO ABOUT 2 MILES AT TIMES. LOW CLOUDS HAVE MOVED IN
ACROSS W MA/N CT INTO RI AS WARM FRONT APPROACHES. HOWEVER...NOT
SEEING MUCH IN THE WAY OF SHOWERS OTHER THAN ISOLD ACTIVITY WELL S
OF THE REGION. MOST ORGANIZED SHOWERS SEEN ACROSS E PA INTO
CENTRAL NY WHICH IS MOVING N-NE INTO UPSTATE NY ON LATEST NE
REGIONAL 88D RADAR MOSAIC.

TEMPS AT 08Z REMAIN IN THE MID 60S TO LOWER 70S ACROSS MOST
AREAS...THOUGH A BIT COOLER ACROSS THE CAPE AND ISLANDS WITH LIGHT
ONSHORE WINDS. NOTING DEWPTS UP TO THE LOWER 70S WITH PATCHY DENSE
FOG ACROSS LONG ISLAND...BUT WITH LIGHT S-SE WINDS...LOOKS LIKE
THIS SHOULD REMAIN S OF THE REGION THROUGH SUNRISE.

AS FOR TODAY...WARM FRONT WILL TEND TO WEAKEN AS IT LIFTS ACROSS
THE REGION. LOOKS LIKE THE BEST LIFT WITH THIS FRONT REMAINS
ACROSS NY STATE INTO WESTERN VT...THOUGH SCT SHOWERS WILL PUSH
ACROSS THE REGION THROUGH EARLY THIS AFTERNOON THEN WILL WEAKEN.
BEST SHOT OF PRECIP WILL BE OVER THE CT VALLEY AND E SLOPES OF THE
BERKSHIRES...WHERE LIKELY POPS ARE IN PLACE AROUND MIDDAY. MAY NOT
SEE PRECIP ACROSS SE MA...CAPE COD AND THE ISLANDS THOUGH PATCHY
FOG MAY LINGER. MAY SEE SOME ISOLD INSTABILITY WORK INTO THE
REGION...WHICH MAY TRIGGER A THUNDERSTORM OR TWO. ALSO NOTING
PWATS AROUND 2 INCHES...SO IF ANY THUNDERSTORMS DO DEVELOP MAY
SEE LOCALIZED HEAVY RAINFALL.

THE MUGGIES RETURN AS SURGE OF HIGHER DEWPTS WILL PUSH IN THIS
AFTERNOON. EXPECT HIGHS MAINLY IN THE LOWER-MID 80S AWAY FROM THE
S COAST...WHERE READINGS WILL HOLD IN THE 70S WITH THE ONSHORE
WIND.

&&

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

TONIGHT...
EXPECT COLD FRONT TO SLOWLY APPROACH THE REGION OUT OF NY STATE.
SHOULD REMAIN DRY...EXCEPT FOR SOME WIDELY SCT SHOWERS POSSIBLE
ACROSS NW MA EARLY TONIGHT. HAVE INCREASED CHANCE POPS AFTER
MIDNIGHT FROM W-E. SOME SHORT RANGE MODEL DIFFERENCES IN HANDLING
MOISTURE WITH AND AHEAD OF THE FRONT...THOUGH SOUPY AIRMASS
REMAINS IN PLACE SO COULD SEE SCT PRECIP. ALSO HELD OFF MENTION
OF THUNDER AS BEST INSTABILITY REMAINS CLOSER TO THE FRONT. WILL
ALSO SEE FOG RETURN ESPECIALLY ACROSS S COASTAL AREAS ESPECIALLY
THE CAPE AND ISLANDS AS TEMPS ONLY DROP TO AROUND 70.

WEDNESDAY...
COLD FRONT SLOWLY CROSSES THE REGION. BEST INSTABILITY ALSO MOVES
IN BY MIDDAY...WITH K INDICES IN THE LOW-MID 30S...CAPES RISING TO
1000-1200 J/KG BY MIDDAY ESPECIALLY ACROSS CENTRAL AND EASTERN
AREAS ALONG WITH TQ VALUES IN THE UPPER TEENS SIGNALING SOME
ELEVATED CONVECTION.BIG CONCERN THOUGH IS THE INCREASING PWATS...
UP TO 2 TO 2.2 INCHES WITH GOOD LOW LEVEL MOISTURE CONVERGENCE.
COULD SEE A FEW STRONG STORMS THOUGH CHANCE LIMITED WITH CLOUD
COVER...BUT BETTER SHOT FOR HEAVY DOWNPOURS WHICH COULD CAUSE
LOCALIZED URBAN AND POOR DRAINAGE FLOODING.

EXPECT THREAT FOR THUNDER TO WIND DOWN ACROSS ROUTE 2 AREA AROUND
OR AFTER 18Z...WITH BEST SHOT FOR PRECIP SHIFTING TO NEAR AND S OF
THE MASS PIKE THROUGH THE REMAINDER OF THE DAY. FRONT LOOKS TO BE
SLOWING AS IT MOVES S DURING THE AFTERNOON AS WELL. MAY SEE
IMPULSE MOVE ALONG THE FRONT WHICH COULD CAUSE TRAINING OF SHOWERS
AND CONVECTION...ANOTHER PROBLEM FOR POSSIBLE FLOODING.

EXPECT A WARM AND MUGGY DAY WITH DEWPTS IN THE MID 60S TO NEAR 70
AS HIGHS REACH INTO THE MID AND UPPER 80S ACROSS THE LOWER CT
VALLEY AND INTERIOR E MA...EVEN REACHING THE LOWER 80S ON THE
CAPE. TEMPS LOOK TO HOLD IN THE UPPER 70S ON THE ISLANDS.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
BIG PICTURE...
UPPER HIGH PRESSURE REMAINS IN CONTROL OVER THE ATLANTIC COAST WHILE
LOW PRESSURE DIGS OVER THE WESTERN USA.  JET FLOW FROM WESTERN
CANADA RIDES ALONG THE US/CANADIAN BORDER. THE RIDGE SHIFTS TO THE
MIDWEST AND PLAINS OVER THE WEEKEND MAKING ROOM FOR A TROUGH TO DIG
OVER THE CANADIAN MARITIMES.  UPPER HEIGHTS REMAIN AT OR ABOVE
SEASONAL NORMALS THROUGH THE PERIOD. THIS SUGGESTS NORMAL SUMMER
TEMPERATURES...ALTHOUGH DAYTIME HIGHS WILL OF COURSE BE HELD BACK ON
DAYS OF HEAVY SKY COVER OR STRONG EAST FLOW.

THE DAILIES...

WEDNESDAY NIGHT-THURSDAY...MODERATE CONFIDENCE.
COLD FRONT IN SOUTHEAST NEW ENGLAND DURING THE EVENING MOVES
OFFSHORE BEFORE MIDNIGHT. THE FRONT THEN BECOMES ALIGNED WITH THE
UPPER FLOW AND STALLS SOUTH OF THE REGION. SHORTWAVE IN THE UPPER
FLOW MOVES THROUGH DURING THURSDAY...GENERATING A WAVE ALONG THE
FRONT AND MAINTAINING A RISK OF SHOWERS THURSDAY. THE BEST CHANCE
WILL BE SOUTH OF THE MASS PIKE NEAREST THE WAVE AND THE FRONT.
PRECIPITABLE WATER VALUES REMAIN HIGH NEAR THE SOUTH COAST...SO
LOCALLY HEAVY DOWNPOURS WILL CONTINUE TO BE A CONCERN IN SOUTHERN
AREAS.  CLOUDS AND A LIGHT EAST FLOW SHOULD KEEP DAYTIME TEMPS IN
THE 70S.

FRIDAY-SATURDAY...MODERATE TO HIGH CONFIDENCE.
HIGH PRESSURE BUILDS OVER THE REGION WITH CLEARING SKIES AND LIGHT
WINDS. MIXING SHOULD REACH TO AT LEAST 850 MB AND POSSIBLY TO 800
MB. TEMPS AT THESE LEVELS WOULD SUPPORT MAX TEMPS OF 80-85 FRIDAY
AND MID 80S SATURDAY. DEW POINTS 55 TO 65 AND LIGHT WINDS SUGGEST
MIN TEMPS IN THE SAME RANGE AS WELL AS PATCHY FOG.

SUNDAY-MONDAY...LOW CONFIDENCE.
CHANGES IN THE OPERATIONAL MODEL SOLUTIONS REGARDING MOISTURE IN THE
VERTICAL ACTS TO SUPPRESS PCPN IN SOUTHERN NEW ENGLAND DURING THIS
PERIOD. MEANWHILE A SHORTWAVE SWINGS ACROSS NORTHERN NEW ENGLAND
INTO THE MARITIMES...PUSHING A COLD FRONT THROUGH OUR AREA. IT
IS HARD TO TOTALLY KILL OFF POPS WHILE SUCH A MECHANISM IS IN PLACE.
WE WILL MAINTAIN CHANCE POPS FOR THE MOMENT AND AWAIT FUTURE MODEL
RUNS.

&&

.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/...

THROUGH 12Z...MODERATE CONFIDENCE.
MAINLY VFR. MVFR CIGS ACROSS N CT/RI INTO SE MA...WHICH MAY
BRIEFLY LOWER TO IFR THROUGH 12Z. LIGHT/VRBL OR CALM WINDS.

TODAY...MODERATE TO HIGH CONFIDENCE.
PATCHY MVFR CIGS ACROSS N CT/RI/SE AND W MA EARLY WHICH SHOULD
IMPROVE TO VFR AT 4-5KFT. MAINLY VFR VSBYS DURING THE
MORNING...THEN PATCHY MVFR CIGS MAINLY ALONG THE S COAST. BRIEF
MVFR CONDITIONS IN SCT SHOWERS. LOW PROB OF ISOLD AFTERNOON
THUNDERSTORMS. S-SE WIND GUSTS UP TO 20-25 KT ALONG COAST THIS
AFTERNOON...HIGHEST ALONG E COAST.

TONIGHT...MODERATE CONFIDENCE.
CONDITIONS LOWER TO MAINLY MVFR BY 04Z-05Z IN PATCHY FOG. CHANCE
OF SHOWERS ACROSS W MA/N CENTRAL CT THROUGH MOST OF THE NIGHT
WITH CHANCE OF ISOLD THUNDERSTORMS THROUGH 04Z. MAY SEE IFR VSBYS
ACROSS E MA/RI/N CT AFTER 06Z-07Z.

WEDNESDAY...MODERATE CONFIDENCE.
EXPECT MVFR TO LOCAL IFR CONDITIONS IN SCT SHOWERS AS COLD FRONT
SLOWLY CROSSES THE REGION. CHANCE OF AFTERNOON THUNDERSTORMS...
SOME WITH HEAVY DOWNPOURS.

KBOS TERMINAL...HIGH CONFIDENCE IN TAF.

KBDL TERMINAL...HIGH CONFIDENCE IN TAF.

OUTLOOK...WEDNESDAY NIGHT THROUGH SATURDAY...

WEDNESDAY NIGHT-THURSDAY...MODERATE CONFIDENCE.
A COLD FRONT OVER SOUTHEAST MASS/RI IN THE EVENING MOVES OFFSHORE
WITH WINDS BECOMING NORTH OVERNIGHT AND NORTHEAST THURSDAY BUT WITH
SPEEDS BELOW 15 KNOTS.  SHOWERS MOVING UP THE FRONT THURSDAY WILL
BRING AREAS OF MVFR CIGS/VSBYS WITH THE BEST CHANCE IN CT-RI AND
SOUTHEAST MASS.

FRIDAY-SATURDAY...MODERATE-HIGH CONFIDENCE.
HIGH PRESSURE BRINGS CLEARING SKIES. VFR. AREAS OF IFR POSSIBLE IN
EARLY MORNING FOG.

&&

.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.

TODAY...EXPECT LIGHT/VRBL WINDS BECOMING S-SE BY MIDDAY...THEN
SHIFT TO S AS WARM FRONT LIFTS N. MAY SEE GUSTS UP TO 20-25 KT
ACROSS THE NEAR SHORE WATERS...HIGHEST ON THE EASTERN WATERS. SEAS
BUILD UP TO 4 FT...MAINLY ACROSS THE SOUTHERN WATERS.

TONIGHT...MAY SEE LEFTOVER 20-25 KT GUSTS THIS EVENING THEN WILL
DIMINISH. PATCHY FOG DEVELOPS WITH REDUCED VSBYS...BELOW 3 MILES
AFTER MIDNIGHT.

WEDNESDAY...SW WINDS WILL INCREASE...WITH GUSTS UP TO 20 KT ON THE
SOUTHERN OUTER WATERS. EXPECT SEAS TO REMAIN BELOW 5 FT...THOUGH
MAY BRIEFLY REACH 5 FT AT TIMES. CHANCE OF SHOWERS/THUNDERSTORMS
SOME WITH HEAVY RAINFALL.

OUTLOOK...WEDNESDAY NIGHT THROUGH SATURDAY...

WINDS AND SEAS REMAIN BELOW SMALL CRAFT THRESHOLDS THROUGH THE
PERIOD.  A COLD FRONT MOVES OFFSHORE WEDNESDAY NIGHT AND STALLS OVER
THE SOUTHERN WATERS. A DISTURBANCE MOVING ALONG THE FRONT WILL BRING
SHOWERS AND SCATTERED TSTMS WEDNESDAY NIGHT/THURSDAY WITH REDUCED
VSBYS IN ANY HEAVY DOWNPOURS.  HIGH PRESSURE BRINGS FAIR WEATHER
FRIDAY AND SATURDAY.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 10 PM EDT
     THIS EVENING FOR ANZ250.
     SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 8 PM EDT THIS
     EVENING FOR ANZ231-251.
     SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 6 PM EDT THIS
     EVENING FOR ANZ230.

&&

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


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