Area Forecast Discussion
Issued by NWS Boston, MA

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000 FXUS61 KBOX 230548 AFDBOX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TAUNTON MA 148 AM EDT SAT AUG 23 2014 .SYNOPSIS... THE RISK FOR A FEW SHOWERS WILL LINGER INTO SATURDAY...OTHERWISE DRY THIS WEEKEND AS HIGH PRESSURE BUILDS SOUTH INTO NEW ENGLAND LATE SATURDAY INTO SUNDAY. DRY WEATHER WITH A WARMING TREND IS LIKELY DURING THE EARLY AND MIDDLE PORTIONS OF NEXT WEEK. A FRONT MAY APPROACH FROM QUEBEC LATE NEXT WEEK WITH A LOW CHANCE OF UNSETTLED WEATHER. && .NEAR TERM /UNTIL 6 AM THIS MORNING/...
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130 AM UPDATE... BULK OF THE -SHRA ACTIVITY HAS COME TO AN END ACROSS THE REGION AS DRIER AIR SLOWLY BEGINS TO FILTER IN FROM THE NE. THERE IS ONE MORE SHORTWAVE INCOMING THAT HAS LED TO THE DEVELOPMENT OF -SHRA IN VT/NH...BUT IT WILL LIKELY TAKE MORE TIME FOR THESE TO ARRIVE. IF THEY DO AT ALL. PREVIOUS DISCUSSION... THE COLUMN BEGINS TO DRY FROM THE NORTH AS NOTED BY DECREASING PWATS AND MUCH LOWER KI VALUES APPROACHING FROM THE NE. BEST CHANCE OF ANY SHOWERS WILL BE BEFORE MIDNIGHT. STRATUS WILL LIKELY REDEVELOP TONIGHT WITH PLENTIFUL LOW LEVEL MOISTURE IN LIGHT EASTERLY FLOW. SOME FOG LIKELY AS WELL BUT WE ARE NOT EXPECTING IT TO BE WIDESPREAD. CAN NOT RULE OUT SOME PATCHY DRIZZLE IN EASTERN NEW ENG AS MID LEVEL DRYING MOVES IN OVER LOW LEVEL MOISTURE.
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&& .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SUNDAY/... SATURDAY... MID LEVEL TROF AXIS AND LAST SHORTWAVE SWINGS SOUTH ACROSS THE REGION...BUT AT THE SAME TIME MID LEVEL DRYING IS MOVING IN SO EXPECT LESS COVERAGE OF SHOWERS. BEST CHANCE WILL BE IN N/NW ZONES AS A SECONDARY AREA OF HIGHER MOISTURE AND KI VALUES MOVES IN FROM THE N. HOWEVER...IMPROVEMENT AND PARTIAL CLEARING EXPECTED BY MID/LATE AFTERNOON AS THE TROF SHIFTS S OF THE REGION. TEMPS EXPECTED TO BE SIMILAR TO TODAY...PERHAPS A FEW DEGREES WARMER IN SOME INTERIOR LOCATIONS BUT STILL BELOW NORMAL. SATURDAY NIGHT... SFC HIGH BUILDS INTO SNE WHICH WILL BRING MOSTLY CLEAR SKIES AND LIGHT WINDS. HOWEVER...PATCHY DENSE RADIATION FOG EXPECTED IN NORMAL FOG PRONE LOCATIONS. A COOL NIGHT WITH MINS MOSTLY IN THE 50S. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... HIGHLIGHTS... * DRY WEATHER EXPECTED FOR MOST OF THE PERIOD * WARMER...MORE HUMID CONDITIONS MOVE IN AROUND EARLY TO MIDDLE PORTIONS OF NEXT WEEK * UNCERTAINTY CONTINUES AS A COLD FRONT APPROACHES FROM QUEBEC LATE NEXT WEEK OVERVIEW AND MODEL PREFERENCES... MEDIUM RANGE MODELS REMAIN IN PRETTY GOOD AGREEMENT INTO EARLY NEXT WEEK...THEN START TO DIVERGE AROUND THE THURSDAY INTO EARLY FRIDAY TIMEFRAME DUE TO THE APPROACH OF A COLD FRONT OUT OF QUEBEC. ALSO NOTING MODELS ARE TRYING TO BRING A SYSTEM AROUND THE WESTERN PERIPHERY OF THE BERMUDA HIGH OUT OF THE TROPICS. USED A BLEND OF AVAILABLE MODELS THROUGH WEDNESDAY...THEN TRANSITIONED OVER TO THE ENSEMBLES WITH LESSER EMPHASIS PLACED ON THE 00Z/12Z OP RUNS LATE NEXT WEEK. 00Z/12Z ECMWF RUNS SEEM A BIT TOO FAST IN BRINGING THE FRONT ACROSS THE REGION ON THU...WHILE THE 12Z GFS BRINGS THE FRONT ACROSS LATE THU NIGHT/FRI...KIND OF CATCHING UP TO THE EC. AGREE WITH PREVIOUS FORECASTER WITH REGARDS TO THE STRENGTH OF THE DEVELOPING RIDGE OVER THE REGION...WHICH MAY SLOW THINGS DOWN FURTHER. DETAILS... SUNDAY...HIGH PRES AT SURFACE AND ALOFT WILL BUILD DOWN THE COAST OUT OF EASTERN CANADA. ONSHORE FLOW WILL HOLD TEMPS IN THE LOWER 70S ALONG THE COAST...RANGING UP TO THE UPPER 70S ACROSS THE CT VALLEY. MONDAY THROUGH WEDNESDAY...HIGH PRES RIDGE BUILDS FROM THE MARITIMES TO THE MID ATLC STATES OVER TIME...WITH THE RIDGE AXIS OVER THE TOP OF THE REGION ON MONDAY THAT SLOWLY SINKS S. THIS WILL CAUSE WINDS TO SHIFT TO S-SW...BRINGING MILDER AND MORE HUMID AIR INTO THE REGION. EXPECT TO SEE HIGHS MAINLY IN THE LOWER-MID 80S DURING THIS TIMEFRAME. WITH LIGHT PRES GRADIENT ON MON AND TUE...SEA BREEZES WILL LIKELY DEVELOP KEEPING IT A BIT COOLER ALONG THE SHORELINE. ONCE THE S-SW FLOW IS ESTABLISHED... TEMPS ALONG THE S COAST MAY ALSO BE A BIT COOLER ON WED. SOME CLOUDS MAY START TO MOVE IN WED NIGHT...BUT TIMING IN QUESTION. THURSDAY-FRIDAY...LOWER CONFIDENCE ON THIS PORTION OF THE FORECAST. FOR NOW...MAY SEE FRONTAL SYSTEM TRY TO WORK S OUT OF QUEBEC AROUND LATE THU/THU NIGHT TIMEFRAME. QUESTION WILL ALSO BE HOW MUCH AVAILABLE MOISTURE WILL BE ASSOCIATED WITH THIS SYSTEM. DID KEEP ONLY LOW CHANCE POPS MAINLY FOR THE INTERIOR FOR THU AFTERNOON/EVENING. VERY LITTLE INSTABILITY WITH THIS...BUT CAN NOT RULE OUT AN ISOLD TSTM SO DID MENTION THIS. CURRENT FORECAST SUGGESTS A DRIER AND COOLER DAY ON FRIDAY. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
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FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM...THROUGH SUNDAY...HIGH CONFIDENCE. THROUGH MID DAY... PERIODS OF MVFR AND ISOLATED IFR IN LOW CIGS WILL CONTINUE BUT GRADUALLY LIFT ESPECIALLY AFTER SUNRISE. SOME AREAS REMAIN VFR. MOST TERMINALS SHOULD BE VFR BY MID DAY AND THEN REMAIN SO. NOT EXPECTED MUCH FOG THIS MORNING. WINDS MAINLY NE. AFTER MID DAY TODAY... MAINLY VFR. SOME PATCHY FOG POSSIBLE TONIGHT BUT MAINLY AT TYPICALLY PRONE TERMINALS. KBOS TERMINAL...HIGH CONFIDENCE IN OVERALL TAF TRENDS...LOWER CONFIDENCE IN EXACT TIMING OF IMPROVEMENT LATER THIS MORNING. KBDL TERMINAL...HIGH CONFIDENCE IN TAF TRENDS...LOWER CONFIDENCE IN EXACT TIMING OF IMPROVEMENT. OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY... HIGH CONFIDENCE VFR. LOW PROBABILITY OF PATCHY MVFR/IFR FOG EACH NIGHT. SEA BREEZES POSSIBLE MONDAY AND TUESDAY.
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&& .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT-TERM...THROUGH SATURDAY NIGHT...HIGH CONFIDENCE. E/NE FLOW WILL PERSIST THROUGH THE PERIOD. WINDS COULD GUST TO 15-20 KT TONIGHT INTO SAT GIVEN MODEST GRADIENT IN PLACE...BUT A DECREASE IN WIND EXPECTED LATE SAT AND ESPECIALLY SAT NIGHT AS THE SFC HIGH BUILDS INTO REGION. OUTLOOK...SUNDAY THROUGH WEDNESDAY... HIGH CONFIDENCE. HIGH CONFIDENCE. QUIET BOATING WEATHER IS EXPECTED FOR MUCH OF THIS PERIOD WITH HIGH PRESSURE ACROSS THE REGION. LOW PROBABILITY OF PATCHY OVERNIGHT FOG LIMITING VISIBILITIES. SEAS MAY APPROACH 5 FT ACROSS THE OUTERMOST SOUTHERN COASTAL WATERS ON WEDNESDAY WITH INCREASING S SWELL. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...NONE. NH...NONE. RI...NONE. MARINE...NONE. && $$ SYNOPSIS...KJC/EVT NEAR TERM...KJC/DOODY SHORT TERM...KJC LONG TERM...EVT AVIATION...DOODY/EVT MARINE...KJC/EVT

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