Area Forecast Discussion
Issued by NWS Boston, MA

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000 FXUS61 KBOX 101405 AFDBOX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TAUNTON MA 1005 AM EDT THU JUL 10 2014 .SYNOPSIS... A COLD FRONT ALONG THE SOUTH COAST THIS MORNING WILL REMAIN STATIONARY TODAY AND TONIGHT...YIELDING LOTS OF CLOUDS AND POSSIBLY A FEW SHOWERS TO THE SOUTH COAST. ELSEWHERE MAINLY DRY WEATHER PREVAILS TODAY INTO SATURDAY WITH SEASONABLE TEMPERATURES AND TURNING LESS HUMID. UNSETTLED WEATHER RETURNS LATE SUNDAY INTO EARLY NEXT WEEK WITH THE RISK OF SHOWERS AND THUNDERSTORMS ALONG WITH INCREASING HUMIDITY. && .NEAR TERM /UNTIL 7 PM THIS EVENING/...
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10 AM UPDATE... THE REMNANTS OF UPSTREAM CONVECTION JUST ALONG AND AHEAD OF A STALLED SFC COLD FRONT HAS DIMINISHED ACROSS NANTUCKET THIS MORNING. WITH THE FRONT NOT EXPECTED TO MAKE MUCH MOVEMENT...WILL NEED TO WATCH FURTHER UPSTREAM CONVECTION CURRENTLY OFF THE NJ COAST WHICH MAY SKIRT THE ISLANDS/CAPE BY LATE DAY. OTHERWISE...DRY AIR WILL CONTINUE TO STREAM IN FROM THE NW SO ACTUALLY HAVE DWPTS DROPPING AS MIXING TAKES HOLD. MINOR ADJUSTMENTS TO POPS...WITH TEMPS AND DWPTS BROUGHT TO CURRENT TRENDS WITH THIS UPDATE. PREVIOUS DISCUSSION... THE COLD FRONT CONTINUES TO SLOWLY MOVE ACROSS SOUTHERN NEW ENGLAND EARLY THIS MORNING. LOOKING AT SURFACE OBS DEWPOINTS...FRONT IS STRADDLED OVER MARSHFIELD MA DOWN TO GROTON CT. AS THE LOW LEVEL JET CONTINUES TO INCREASE...SHOWERS AND THUNDERSTORMS HAVE CONTINUED TO DEVELOP. ALTHOUGH THERE IS A LACK OF STRONG INSTABILITY...THERE IS ENOUGH DEEP LAYER MOISTURE AS NOTICED IN K VALUES COMBINED WITH STRONG SHEAR TO ALLOW FOR THESE STORM TO CONTINUE. BELIEVE SEVERE WEATHER POTENTIAL IS LOW...CANNOT RULE OUT SOME STRONG STORMS WITH GUSTY WINDS AND LIGHTNING. HEAVY RAINFALL CAN ALSO BE AN ISSUE AS PWAT VALUES ARE ABOVE 1.5 INCHES. STRONGEST STORMS ARE CURRENTLY OVER THE CAPE...BUT LOOKING DOWNSTREAM MORE STORMS ARE FESTERING SOUTH OF LONG ISLAND. SINCE THE FLOW IS FROM THE SW TO NE...DO NOT SEE A REASON ON WHY THESE STORMS WOULD NOT MAKE IT TO THE SOUTHERN WATERS. NORTH OF THE FRONT...DRY AIR IS MOVING INTO THE REGION ALLOWING FOR MORE COMFORTABLE CONDITIONS AND TEMPS INTO THE MID 60S. TODAY... FRONT WILL CONTINUE TO LINGERING SOUTH OF THE CAPE AND ISLANDS TODAY ALLOWING FOR A SLIGHT CHANCE FOR SHOWERY WEATHER. OTHERWISE DRY AIR WILL CONTINUE TO WORK INTO THE REGION RESULTING IN COMFORTABLE CONDITIONS. TEMPERATURES WILL ALSO BE A TAD COOLER WITH HIGHS REACHING ONLY IN THE MID TO UPPER 80S. BECAUSE OF THE HIGH PRESSURE BUILDING INTO THE REGION...WINDS WILL GENERALLY BE LIGHT ALLOWING FOR SEA BREEZE DEVELOPMENT ALONG BOTH COASTLINES.
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&& .SHORT TERM /7 PM THIS EVENING THROUGH 6 PM FRIDAY/... TONIGHT... MODELS CONTINUE TO SHOW THAT THE NEARLY STATIONARY FRONT WILL LINGER SOUTH OF THE CAPE AND ISLANDS TONIGHT. THIS FRONT MAY ALLOW FOR SOME SHOWERY WEATHER ESP ACROSS THE SOUTHERN WATERS AS WELL AS SOME CLOUDS. PATCHY FOG MAY ALSO DEVELOP SOUTH OF THE FRONT IN THE WARMER/HUMID AIRMASS. HIGH PRESSURE ACROSS THE INTERIOR WILL KEEP DRY AIR OVER THE AREA WITH MOSTLY CLEAR SKIES. LOWS IN THE MID 50S TO LOW 60S...WARMER ACROSS THE METRO REGION OF BOS AND PVD. TOMORROW... HIGH PRESSURE WILL BUILD OVER THE REGION ON FRIDAY WITH THE STALLED FRONT STILL LINGERING TO THE SOUTH. ALTHOUGH THE LOW LEVELS WILL BE DRY...SOME INCREASE MOISTURE IN THE MID TO UPPER LEVELS MAY PRODUCE A FEW MORE CLOUDS. SOME MODEL GUIDANCE IS TRYING TO SQUEEZE OUT SOME QPF ON FRIDAY AS UPPER LEVEL JET MOVES OVER THE REGION PROVIDING SOME LIFT. BECAUSE THERE IS A GOOD AMOUNT OF DRY AIR IN THE LOW LEVELS PER SOUNDINGS...KEPT THE CHANCE OUT OF THE FORECAST FOR NOW. TEMPERATURES WILL CONTINUE TO BE COOLER THEN THE START OF THE WORK WEEK WITH HIGHS REACHING IN THE LOW TO MID 80S. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... HIGHLIGHTS... * PLEASANT/DRY WEATHER AND LESS HUMID FRI NIGHT/SAT * BECOMING UNSETTLED LATE SUN INTO EARLY NEXT WEEK SYNOPTIC SCALE FLOW AND MODEL PREFERENCES... FLOW TEMPORARILY DEAMPLIFIES EARLY IN THE PERIOD TO PROVIDE DRIER AND LESS HUMID MID SUMMER WEATHER ACROSS SOUTHERN NEW ENGLAND. BY LATER SUNDAY/SUN NIGHT AND ESPECIALLY EARLY NEXT WEEK THE UPPER AIR PATTERN UNDERGOES SIGNIFICANT AMPLIFICATION WITH A PIECE OF THE POLAR VORTEX DIVING SOUTHWARD INTO THE GREAT LAKES. GEFS ANOMALIES SUGGEST 500 MB HEIGHTS FALL TO ABOUT -3 SD BELOW OVER THIS REGION EARLY NEXT WEEK. THIS CLOSED LOW WILL THEN TRACK NORTHEAST INTO SOUTHERN ONTARIO AND QUEBEC EARLY NEXT WEEK. HOWEVER THE LEADING EDGE OF ITS FRONTAL ZONE WILL PROVIDE UNSETTLED WEATHER FOR SOUTHERN NEW ENGLAND POSSIBLY AS EARLY AS LATER SUNDAY BUT MORE LIKELY MON AND TUE OF NEXT WEEK. ALL OF THE MODEL GUIDANCE INCLUDING THE GEFS AND ECENS IS IN VERY GOOD AGREEMENT ON THE EVOLUTION OF THIS HIGH AMPLITUDE TROUGH ALONG WITH THE SYNOPTIC SCALE FLOW PATTERN ACROSS NEW ENGLAND. THUS WILL FOLLOW A MODEL BLEND FOR THIS PORTION OF THE FORECAST. DAILY DETAILS... FRI NIGHT AND SATURDAY...VERY PLEASANT DRY WEATHER WITH COMFORTABLE HUMIDITY AND LIGHT WINDS AS HIGH PRES CREST OVER THE REGION. WEAK PGRAD WILL SUPPORT AFTERNOON SEA BREEZES KEEPING THE COASTLINE SLIGHTLY COOLER THAN THE INTERIOR. DEW PTS IN THE 50S WILL SUPPORT LOWS IN THE U50S TO L60S AND HIGHS 80-85. SUN/MON/TUE....WEATHER BECOMES UNSETTLED AS UPPER AIR PATTERN AMPLIFIES SIGNIFICANTLY. THE GFS AND ITS ENSEMBLES ARE ON THE FAST EDGE OF THE GUIDANCE WITH THE THREAT OF SHOWERS ARRIVING SUN. REMAINDER OF THE GUID IS SLOWER KEEPING DRY WEATHER HERE UNTIL NIGHTFALL/SUN EVENING. HIGHER RISK OF SHOWERS/T-STORMS COMES MON AND TUE AS FULL LATITUDE TROUGH OVER THE GREAT LAKES ADVECTS NORTHEAST INTO SOUTHERN ONTARIO AND QUEBEC. STRONG FRONTAL ZONE ASSOCIATED WITH THIS SYSTEM WHICH WILL IMPACT THE REGION MON AND TUE WITH AN INCREASED RISK OF SHOWERS/T-STORMS. TROUGH MAY HAVE ENOUGH AMPLIFICATION TO BACK THE MID LEVEL FLOW FOR GOOD ATLC INFLOW YIELDING HEAVY RAINFALL THREAT. ALSO TURNING WARMER AND MORE HUMID THIS PERIOD AS WELL. MIDDLE OF NEXT WEEK...ENSEMBLES SUGGEST MID/UPR LVL TROUGH SHOULD BE MOVING OFFSHORE AROUND THE MIDDLE OF NEXT WEEK. THIS WOULD SUPPORT A TREND TOWARD DRIER AND LESS HUMID WEATHER. && .AVIATION /14Z THURSDAY THROUGH MONDAY/... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /THROUGH FRIDAY/... 7 AM UPDATE... COLD FRONT STALLED ALONG THE SOUTH COAST AT 7 AM. PATCHY FOG NEAR THIS BOUNDARY WILL THIN/ERODE BY MIDDAY. MAINLY VFR CIGS AND MVFR VSBYS THIS MORNING WILL IMPROVE TO VFR BY MIDDAY. ANY SHOWERS/TSTMS TODAY WILL BE CONFINED TO THE SOUTH COAST OR OFFSHORE WATERS. EARLIER DISCUSSION BELOW. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ TODAY...HIGH CONFIDENCE. VFR CONDITIONS EXPECT ACROSS THE CAPE AND ISLAND WHERE LINGERING MVFR CLOUDS AND FOG MAY OCCUR WITHIN ANY SHOWERS. SEA BREEZES ALONG BOTH COASTLINES. TONIGHT...HIGH CONFIDENCE. VFR CONDITIONS EXCEPT POSSIBLE MVFR CIGS CAPE AND ISLANDS. FRIDAY...MODERATE CONFIDENCE. VFR CONDITIONS. LOW PROB OF MVFR CIGS ACROSS THE INTERIOR. KBOS TAF...HIGH CONFIDENCE IN TAF. MODERATE CONFIDENCE ON SEA BREEZE TIMING. KBDL TAF...HIGH CONFIDENCE IN TAF. OUTLOOK...FRIDAY NIGHT THROUGH MONDAY...MODERATE CONFIDENCE. FRIDAY NIGHT AND SATURDAY...HIGH CONFIDENCE FOR VFR/DRY WEATHER AND LIGHT WINDS. SUNDAY-MONDAY...VFR TO START BUT LOWERING TO MVFR LATE SUN/SUN NIGHT AND ESPECIALLY MON AS RISK OF SHOWERS/T-STORMS INCREASES. LOCALLY HEAVY DOWNPOURS POSSIBLE IN ANY THUNDERSTORMS. && .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /TODAY THROUGH FRIDAY/...HIGH CONFIDENCE. A COLD FRONT WILL STALL NEAR OR OVER THE SOUTHERN COASTAL WATERS DURING BEGINNING THIS MORNING AND WILL LAST THROUGH FRIDAY. ANTICIPATE CLOUDS AND SHOWERY WEATHER ALONG THIS STALLED FRONT. WINDS ARE EXPECTED TO BE BELOW 25 KT. SCA CONTINUE FOR THE SOUTHERN OUTER WATERS...BUT SHOULD DROP LATE THIS MORNING AS ROUGH SEAS SLOWLY SUBSIDE AS PERSISTENT SOUTHERLY SWELL WEAKENS. OUTLOOK...FRIDAY NIGHT THROUGH MONDAY...MODERATE CONFIDENCE. FRIDAY NIGHT THROUGH SUNDAY...IDEAL BOATING WEATHER WITH GOOD VSBY/DRY WEATHER AND LIGHT WINDS AS HIGH PRES CREST OVER THE WATERS. SUNDAY NIGHT-MONDAY...HIGH PRES MOVES OFFSHORE WITH RISK OF SHOWERS/T-STORMS INCREASING. SSW WINDS INCREASE AS WELL. && .BOX WATCHES/WARNINGS/ADVISORIES...
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CT...NONE. MA...NONE. NH...NONE. RI...NONE. MARINE...NONE.
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&& $$ SYNOPSIS...NOCERA/DUNTEN NEAR TERM...NOCERA/DUNTEN SHORT TERM...DUNTEN LONG TERM...NOCERA AVIATION...NOCERA/DUNTEN MARINE...NOCERA/DUNTEN

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