Area Forecast Discussion
Issued by NWS Boston, MA

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000 FXUS61 KBOX 262336 AFDBOX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TAUNTON MA 736 PM EDT WED AUG 26 2015 .SYNOPSIS... COLD FRONT ALONG THE EAST MASSACHUSETTS COAST WILL MOVE OFFSHORE TONIGHT. HIGH PRESSURE SLOWLY BUILDS OVER THE REGION INTO THIS WEEKEND...BRINGING DRY AND SEASONABLE WEATHER. THE HIGH BUILDS OFFSHORE BY EARLY NEXT WEEK...ALLOWING FOR THE RETURN OF HAZY...HOT AND HUMID CONDITIONS. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... 725 PM UPDATE... CLOUDS CONTINUE TO THIN OUT ACROSS MOST OF THE REGION EARLY THIS EVENING AS SEEN ON 23Z OBS AND IR SATELLITE IMAGERY. MOST LOCATIONS REPORTING EITHER FEW CLOUDS AROUND 5-6KFT OR CLEAR SKIES. DECK OF LOW AND MID LEVEL CLOUDS TRYING TO MOVE E OUT OF NY STATE TENDING TO DISSIPATE AS IT PUSHES TOWARD THE CT VALLEY AND BERKSHIRES. NOTING DEWPTS CONTINUE TO FALL BACK AS DRIER AIR PUSHES IN ON LIGHT WESTERLY WINDS. STILL SOME HIGHER DEWPTS...AROUND 60 DEGREES...ALONG S COAST...CAPE COD AND THE ISLANDS BUT WILL FALL BACK THERE THROUGH THE NIGHT AS WELL. EXPECT ONLY PATCHY HIGH THIN CLOUDS TO LINGER OVERNIGHT...THOUGH THIS SHOULD ALSO MOVE NE. ANY CLOUDS THAT DO WORK INTO W MA/N CENTRAL CT SHOULD CONTINUE TO DISSIPATE AS THE DRIER AIR WORKS IN. DID LEAVE MENTION OF PATCHY FOG ACROSS PORTIONS OF N CENTRAL AND W MA AFTER 06Z THROUGH AROUND DAYBREAK OR SO...THE NORMALLY PRONE VALLEY LOCATIONS. TEMPS WILL LINGER IN THE UPPER 60S AND 70S THROUGH ABOUT MIDNIGHT...THEN COOLER AIR WILL FILTER IN. CURRENT FORECASTED LOWS LOOK ON TARGET SO ONLY MADE ADJUSTMENTS ON NEAR TERM TEMPS/DEWPTS TO BRING CONDITIONS CURRENT. REMAINDER OF FORECAST IN GOOD SHAPE BUT ALSO BROUGHT NEAR TERM CONDITIONS CURRENT. PREVIOUS FORECAST... SURFACE HIGH PRESSURE OVER THE MIDWEST WILL BUILD IN WITH PLENTY OF SUBSIDENCE. UPPER TROUGH CONTAINS A FAIR AMOUNT OF MOISTURE THROUGH THE COLUMN...BUT MOST OF THIS WILL REMAIN IN NORTHERN NEW ENGLAND AND UPSTATE NEW YORK. SO THE FORECAST WILL BE FAIR AND DRY. PRESSURE GRADIENT IS WEAK ENOUGH FOR SHELTERED AREAS TO DECOUPLE...BUT EVEN EXPOSED AREAS SHOULD HAVE DIMINISHING WEST TO NORTHWEST WINDS. INTERIOR AREAS SHOULD COOL TO NEAR DEW POINT WITH VALUES IN THE MID AND UPPER 50S...COASTAL AREAS AND URBAN CENTERS WILL BE IN THE LOW TO MID 60S. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/... THURSDAY... UPPER TROUGH AXIS IS STILL OVER NEW ENGLAND WITH SOME CLOUD-LEVEL MOISTURE LINGERING AROUND 850 MB. DAYTIME HEATING SHOULD CONVERT THIS TO DIURNAL CU...BUT STILL MAINTAIN PARTLY TO MOSTLY SUNNY SKIES. THE MOST CLOUDS WILL BE IN NORTHERN MASS. TEMPS AT 850 MB WILL BE 10C-11C...WHICH SUPPORTS MAX SFC TEMPS IN THE UPPER 70S AND LOWER 80S...COOLER IN THE HIGHER HILLS AND PARTS OF THE COAST. THURSDAY NIGHT... HIGH PRESSURE REMAINS IN CHARGE. FAIR AND DRY WEATHER WITH MIN TEMPS A COUPLE OF DEGREES COOLER THAN TONIGHT. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... HIGHLIGHTS... * MAINLY DRY AND WARM WITH COMFORTABLE HUMIDITY FRIDAY AND SAT * LATE SUMMER HEAT AND HUMIDITY LOOKS TO RETURN NEXT WEEK OVERVIEW... 12Z MEDIUM RANGE MODEL SUITE CONTINUES IN GOOD AGREEMENT THROUGH A GOOD PORTION OF THIS FORECAST. TYPICAL SUMMER UPPER LEVEL PATTERN DOMINATES...WITH AMPLIFIED RIDGE THAT WORKS SLOWLY E OUT OF THE PLAINS STATES INTO CENTRAL CANADA INTO THIS WEEKEND...WHILE RATHER FLAT FLOW REMAINS ACROSS THE NORTHEAST U.S. AS TIME MOVES ON...THE HIGH AMPLITUDE RIDGE CONTINUES TO WORK E TOWARD THE GREAT LAKES AND HUDSON BAY. DO NOTE A FEW WEAK SHORT WAVES IN THE UPPER FLOW...BUT FEEL WITH LARGE SURFACE RIDGING AND GOOD SUBSIDENCE THESE WILL PROVIDE LITTLE IF ANY PRECIP THROUGH THE MIDDLE OF NEXT WEEK. LAST SEVERAL RUNS OF THE OP GFS CONTINUE TO TRY AND DEVELOP A SOMEWHAT MORE POTENT SHORT WAVE AS IT MOVES ALONG IN THE FLOW AROUND THE SUN INTO MON TIMEFRAME. THE LAST COUPLE OF RUNS OF THE ECMWF ALSO SHOWING A SMALL PROGRESSIVE UPPER CUTOFF LOW SLOWLY MOVING E. HOWEVER...EACH MODEL HANDLES THE SURFACE CONDITIONS RATHER DIFFERENTLY...WITH CHANCE FOR PRECIP REMAINING ON THE GFS WHILE REMAINING DRY ON THE EC AND GGEM EARLY NEXT WEEK. OVERALL...APPEARS THESE MINOR FEATURES PRESENT LITTLE IF ANY PRECIP AS THE LARGE SURFACE HIGH ALONG THE EASTERN SEABOARD WORKS OFFSHORE...ESTABLISHING ACROSS THE WESTERN ATLC. ALSO INTERESTING TO NOTE THAT ALL THREE OP MODEL RUNS /GFS...GGEM AND ECMWF/ TRY TO MOVE T.S. ERIKA OFF THE SE U.S. COAST AROUND TUE-WED...THOUGH HOLDING IT OFFSHORE. SOMETHING TO KEEP AN EYE ON. WENT ALONG WITH AVAILABLE MODEL GUIDANCE THROUGH THIS WEEKEND... THEN TRANSITIONED OVER THE ENSEMBLES AS MODELS DIVERGE ON THEIR INDIVIDUAL SOLUTIONS EARLY NEXT WEEK. OVERALL...IT DOES LOOK LIKE A DRY FORECAST. DETAILS... FRIDAY AND SATURDAY...HIGH CONFIDENCE. HIGH PRESSURE WILL DOMINATE ACROSS THE REGION INTO THIS WEEKEND. EXPECT TEMPS TO RUN CLOSE TO OR A BIT WARMER THAN NORMAL. HIGHS ON FRIDAY IN THE UPPER 70S TO LOWER 80S EXCEPT WHERE SEA BREEZES SET UP HOLDING TEMPS DOWN A FEW DEGREES. WINDS SHIFT AROUND TO S-SW ON SATURDAY...SO WILL SEE TEMPS RISE SEVERAL DEGREES HIGHER THAN ON FRIDAY. READINGS WILL TOP OFF IN THE LOWER-MID 80S... THOUGH DEWPTS WILL REMAIN IN THE MID 50S TO AROUND 60. SUNDAY...LOW TO MODERATE CONFIDENCE. 12Z GFS CONTINUES TO PERSIST IN BRINGING CHANCE POPS ACROSS THE REGION AS WEAK SHORT WAVE MOVES ACROSS...WHILE MOST OTHER GUIDANCE REMAINS DRY. HOWEVER...AS MENTIONED ABOVE...DO NOTE SOME ENERGY SLIDING TOWARD THE REGION ON THE EC AS WELL. SO...CONTINUED WITH MENTION SLIGHT CHANCE POPS WITH BEST CHANCE DURING THE AFTERNOON INTO THE EVENING WITH BEST DIURNAL HEATING. MONDAY THROUGH WEDNESDAY...LOW TO MODERATE CONFIDENCE. INDIVIDUAL MODELS DIVERGE DURING THIS TIMEFRAME AS UNCERTAINTY CONTINUES WITH STRENGTH OF SHORT WAVES BEING DEPICTED ON EACH MODEL AS THEY MOVE ALONG IN THE UPPER FLOW. HOWEVER...AS UPPER RIDGE BUILDS FURTHER E AND LARGE SURFACE HIGH ESTABLISHES OFF THE EASTERN SEABOARD...LOOKS LIKE LATE SUMMER HEAT AND HUMIDITY INCREASES DURING THIS TIMEFRAME. EXPECT HIGHS MAINLY IN THE MID- UPPER 80S THOUGH COULD SEE SOME 90+ DEGREES READINGS AS WELL. VERY IMPRESSIVE WARM SIGNAL CONTINUES. && .AVIATION /00Z THURSDAY THROUGH MONDAY/... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /THROUGH THURSDAY/... TONIGHT...HIGH CONFIDENCE. VFR. PATCHY IFR FOG LATE TONIGHT INTERIOR VALLEYS. THURSDAY...HIGH CONFIDENCE. VFR. THURSDAY NIGHT...HIGH CONFIDENCE. VFR. PATCHY IFR FOG LATE AT NIGHT IN THE INTERIOR. KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. KBDL TERMINAL...HIGH CONFIDENCE IN TAF. OUTLOOK /FRIDAY THROUGH MONDAY/...HIGH CONFIDENCE. FRIDAY AND SATURDAY...MAINLY VFR. WEAK SEA BREEZES SHOULD DEVELOP EACH DAY ALONG THE IMMEDIATE COASTS. LOW CHANCE FOR BRIEF PATCHY LATE NIGHT/EARLY MORNING FOG ACROSS NORMALLY PRONE INTERIOR VALLEYS. SUNDAY...MAINLY VFR. LOW CHANCE FOR BRIEF LOCAL MVFR IN SCT SHOWERS/TSTMS MAINLY AFTERNOON/EVENING AWAY FROM THE S COAST. MONDAY...VFR. && .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /THROUGH THURSDAY NIGHT/...HIGH CONFIDENCE. QUIET BOATING WEATHER WITH WINDS AND SEAS BELOW SCA THRESHOLDS THROUGH THE PERIOD. WIND BECOMING WEST-NORTHWEST THROUGH THE PERIOD. OUTLOOK /FRIDAY THROUGH MONDAY/...HIGH CONFIDENCE. EXPECT WINDS AND SEAS REMAINING BELOW SMALL CRAFT LEVELS THROUGH MOST OF THE PERIOD. SW WINDS MAY PICK UP DURING SUNDAY ON THE SOUTHERN OUTER WATERS WITH SEAS POSSIBLY REACHING 5 FEET. WILL CONTINUE TO MONITOR IN CASE A SMALL CRAFT IS NEEDED THERE. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...NONE. RI...NONE. MARINE...NONE. && $$ SYNOPSIS...WTB/EVT NEAR TERM...WTB/EVT SHORT TERM...WTB LONG TERM...EVT AVIATION...WTB/EVT MARINE...WTB/EVT

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