Area Forecast Discussion
Issued by NWS Boston, MA

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000 FXUS61 KBOX 280537 AFDBOX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TAUNTON MA 137 AM EDT TUE APR 28 2015 .SYNOPSIS... COOLER CONDITIONS MIXED IN WITH BOUTS OF WET WEATHER PREVAIL INTO THE EARLY PART OF THE WEEK. A BRIEF LULL WEDNESDAY UNDER HIGH PRESSURE AND WARMER CONDITIONS IS QUICKLY REPLACED BY A RETURN OF COOLER AND WETTER CONDITIONS INTO THE END OF THE WEEK. THE WEEKEND LOOKS BETTER WITH SEASONABLE AND DRY CONDITIONS. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... 10 PM UPDATE... A BACKDOOR COLD FRONT CONTINUES TO MOVE THROUGH THE AREA ON THE LEADING EDGE OF A MID LVL SHORTWAVE WHICH IS ACTING TO FORCE THE VORTEX ALOFT TO SHIFT S. THE CONVERGENCE OF THESE FORCING MECHANISMS IS WORKING ON WHAT REMAINING MOISTURE THERE IS THROUGH THE COLUMN TO GENERATE A BAND OF SHOWERS /WITH SOME EMBEDDED HEAVIER ELEMENTS/ TO MOVE SSW ACROSS THE ERN PORTIONS OF THE FA THIS HOUR. IT/S LIKELY THAT THESE WILL CONTINUE TO MOVE THROUGH...AT LEAST THROUGH ABOUT 06Z...BUT GENERALLY HOLD E OF THE WORCESTER HILLS OF MA...MOVING THROUGH RI AS WELL. HAVE UPDATED POPS TOWARD THIS THINKING. NOTE THAT THE ONSET OF THESE SHOWERS MAY ALSO BE ACCOMPANIED BY A BRIEF WIND GUST OVER 30 MPH. NOT EXPECTING ANY SERIOUS ISSUES WITH THIS AS RAINFALL RATES ARE MARGINAL AND THE HEAVIER ELEMENTS ARE SMALL AND FAST MOVING. TONIGHT... BACK-DOOR COLD FRONT CONTINUING TO PUSH S THROUGH THE REGION. SHOWER ACTIVITY CONTINUING ALONG AND AHEAD THOUGH STRUGGLING AGAINST DRIER AIR ACROSS THE REGION /SEE 12Z SOUNDINGS FROM AROUND S NEW ENGLAND/. NEVERTHELESS STRONG FORCING OF AVAILABLE MOISTURE PER MID-LEVEL IMPULSE TO THE BACK-BUILDING NEARLY-STACKED LOW INTO THE GULF OF MAINE SHOULD YIELD ACTIVITY. IN ITS WAKE EXPECT COLD-AIR ADVECTION TO PROCEED WITHIN THE LOW-LEVELS ALLOWING A STEEPENING BOUNDARY- LAYER PROFILE /SEE 12Z UPSTREAM SOUNDINGS OVER NEWFOUNDLAND/ THAT ALLOWS FOR THE MIX-DOWN OF FASTER MOMENTUM AND DRIER AIR TO THE SURFACE. SO WILL SEE DECENT RAIN CHANCES THAT CONTINUE INTO MIDNIGHT. LIKELY OR HIGHER POPS. LOW CONFIDENCE WITH RESPECT TO THUNDER. NW-FLOW BACKS OUT OF THE N/NE AND BECOMES BLUSTERY BEHIND THE FRONT WITH GUSTS AROUND 20 MPH...STRONGEST ACROSS THE MASS E-SHORE ESPECIALLY CAPE ANN / CAPE COD / ISLANDS. GUSTS IN THESE LOCATIONS COULD GET AS HIGH AS 35 MPH IF CONDITIONS ARE JUST RIGHT. UPSTREAM OBSERVATIONS WOULD SUGGEST POTENTIAL OUTCOMES. THE S PUSH OF A COLDER AIRMASS DROPS TEMPERATURES TO LOWS AROUND THE LOW-40S. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM WEDNESDAY/... TUESDAY... CONDITIONS IMPROVE BEHIND THE COLD FRONT. IN ITS WAKE EXPECT A WELL- MIXED PROFILE WITH A CONTINUED COLD-POOL ALOFT ENHANCED BY ABUNDANT SUNSHINE AND DAYTIME HEATING. ANTICIPATE BLUSTERY N-WINDS WITH GUSTS AROUND 20-25 MPH AND DRIER AIR WITH RELATIVE HUMIDITY VALUES FALLING DOWN TO 30-PERCENT. SOME ELEVATED FIRE WEATHER POTENTIAL CONCERNS... BUT IN COLLABORATION WITH OTHER FORECAST OFFICES AND FIRE-WEATHER STATE LIAISONS...FEEL THE THREAT IS MARGINAL AND WILL NOT BE GOING WITH ANY HEADLINES. OVERALL A DRY FORECAST AS BETTER FORCING OF AVAILABLE MOISTURE STAYS TO THE E. CLOUDS CONTINUE TO BE AN ISSUE ACROSS E NEW ENGLAND ALONG THE W-PERIPHERY OF THE NEARLY-STACKED LOW CONTINUING TO SPIN ACROSS THE WATERS SE OF CANADA. HIGHS INTO THE UPPER-50S TO LOW-60S. BUT COMBINED WITH WINDS... COULD FEEL 5-DEGREES COOLER. SLIGHTLY BELOW AVERAGE CONDITIONS MAKING IT FEEL UNSEASONABLE. TUESDAY NIGHT... REMAINING QUIET AND DRY AS NW-FLOW DIMINISHES. CLOUDS CONTINUE TO LINGER ALONG THE W-PERIPHERY OF THE LOW SE OF CANADA. IT IS POSSIBLE SOME LOCATIONS COULD RADIATE OUT SHOULD WINDS BECOME LIGHT ENOUGH. CONFIDENCE IS WITHIN SHELTERED VALLEY REGIMES. LOWS AROUND THE UPPER- 30S TO LOW-40S. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... HIGHLIGHTS... * PICK OF THE WEEK IS WEDNESDAY WITH DRY WEATHER AND NORMAL TO ABOVE NORMAL TEMPS * UNSETTLED WEATHER RETURNS FOR THURSDAY AND FRIDAY * IMPROVEMENT EXPECTED FOR THE WEEKEND THE MODELS HAVE COME INTO BETTER AGREEMENT REGARDING THE TRACK AND STRENGTH OF THE LOW PRESSURE DEVELOPING OFF THE NORTH CAROLINA COAST. HOWEVER...THEY CONTINUE TO STRUGGLE WITH THE TIMING AND HOW QUICKLY THE LOW PULLS AWAY FROM SOUTHERN NEW ENGLAND LATE IN THE WEEK. THESE DISCREPANCIES THEN AFFECT THE TIMING OF FEATURES THROUGH THE REMAINDER OF THE MODEL RUN. WEDNESDAY...SHOULD BE THE PICK OF THE WEEK. DRY WEATHER AND TEMPERATURES IN THE NORMAL TO ABOVE NORMAL RANGE ARE EXPECTED. THURSDAY AND FRIDAY...LOW PRESSURE MOVES AWAY FROM THE NORTH CAROLINA COAST AND STARTS TRACKING NORTHEASTWARD TOWARDS SOUTHERN NEW ENGLAND. RIGHT NOW...THE TRACK LOOKS TO KEEP IT WELL OUTSIDE THE BENCHMARK WITH LIMITED IMPACT ON OUR LAND ZONES...BUT SIGNIFICANT IMPACT ON THE MARINE ZONES. MAIN IMPACT TO THE LAND WILL BE OVERCAST SKIES AND POSSIBLY A BIT OF RAIN CLOSE TO THE COAST. HOWEVER...THIS IS HIGHLY DEPENDENT UPON THE EVENTUAL TRACK OF THE LOW. MODEL RUNS DO SEEM TO BE COMING INTO BETTER AGREEMENT ON KEEPING THE LOW FAIRLY PROGRESSIVE BUT THIS IS A NEW TREND SO WILL KEEP AN EYE ON THIS OVER THE NEXT COUPLE OF DAYS. SATURDAY THROUGH MONDAY...THERE IS POTENTIAL FOR A VERY NICE WEEKEND WITH SOUTHERLY FLOW BRINGING IN WARMER TEMPERATURES AND PLEASANT... DRY WEATHER. RAIN SHOWERS LOOK TO MOVE INTO SOUTHERN NEW ENGLAND SOMETIME SUNDAY INTO MONDAY. THIS AS A RESULT OF LOW PRESSURE MOVING THROUGH QUEBEC AND DRAGGING A COLD FRONT THROUGH SOUTHERN NEW ENGLAND. THE TIMING OF THIS WILL LARGELY BE BASED ON HOW THURSDAY AND FRIDAY TURN OUT. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/...
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FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. THROUGH 12Z...HIGH CONFIDENCE. MAINLY VFR FOR AREAS W OF A LINE FROM IJD-ORH-MHT. A MIX OF MVFR/VFR FOR AREAS E AS RAINFALL CONTINUES THROUGH ABOUT 10Z. WINDS SHIFT TO THE NNE...WITH GUSTS INCREASING TO AROUND 25 KT. TUESDAY...HIGH CONFIDENCE. LOW-END VFR WITH SOME MVFR CIGS EARLY BECOMING SCT. WIND GUSTS DROP TO MAINLY 15-25 KT THROUGH THE DAY. TONIGHT AND WEDNESDAY...HIGH CONFIDENCE. VFR. INCREASING MID-LOW VFR CLOUDS BUILD IN FROM THE N DURING THE DAY. LOW CHANCE FOR A SPRINKLE. KBOS TAF...HIGH CONFIDENCE IN TAF. KBDL TAF...HIGH CONFIDENCE IN TAF. .OUTLOOK /WEDNESDAY NIGHT THROUGH SATURDAY/... THURSDAY AND FRIDAY...LOW CONFIDENCE. MAINLY VFR WITH A LOW PROBABILITY OF MVFR/IFR CONDITIONS NEAR THE COAST. SATURDAY...MODERATE CONFIDENCE. VFR.
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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 /TILL TUESDAY EVENING/... 130 PM UPDATE... GUSTY WINDS ACROSS THE INTERIOR...BUT A WEAK SEA-BREEZE BOUNDARY REMAINS ALONG THE COAST LENDING TO SOME VARIANCE IN THE WIND AT TIMES. NEVERTHELESS THE DOMINANT FLOW WILL BE NW WITH GUSTS UP TO 20 KTS. SEAS LIKELY TO ENHANCE...ESPECIALLY TOWARDS EVENING AS A COLD FRONTAL BOUNDARY DROPS S ALONG WHICH SHOWERS ARE EXPECTED. WITH PASSAGE...WIND GUSTS INCREASE OUT OF THE N WITH THE POTENTIAL FOR GALES. THESE WINDS CONTINUE INTO MORNING DIMINISHING THROUGH TUESDAY. SMALL-CRAFTS CONTINUE...GALES FORECAST TO BE SHORT-LIVED SO WILL EMPHASIZE THREAT IN THE SMALL-CRAFT ADVISORY. WAVES BUILDING AROUND 6-8 FEET ON THE E-OUTER WATERS...SUBSIDING INTO TUESDAY NIGHT. .OUTLOOK /WEDNESDAY THROUGH SATURDAY/... WEDNESDAY...HIGH CONFIDENCE. QUIET BOATING WEATHER. THURSDAY THROUGH SATURDAY...HIGH CONFIDENCE IN TRENDS...LOWER CONFIDENCE IN DURATION AND MAGNITUDE OF TRENDS. WINDS AND SEAS WILL INCREASE IN RESPONSE TO A STRONG LOW PRESSURE SYSTEM PASSING EAST OF THE COASTAL WATERS. SMALL CRAFT ADVISORIES WILL BE NECESSARY WITH GALE WARNINGS POSSIBLE. && .BOX WATCHES/WARNINGS/ADVISORIES...
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CT...NONE. MA...NONE. RI...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR ANZ231- 232. SMALL CRAFT ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR ANZ230- 233-234. SMALL CRAFT ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR ANZ235- 237-256. SMALL CRAFT ADVISORY UNTIL 8 AM EDT WEDNESDAY FOR ANZ250-254. SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ251. SMALL CRAFT ADVISORY UNTIL 8 AM EDT WEDNESDAY FOR ANZ255.
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&& $$ SYNOPSIS...RLG/SIPPRELL NEAR TERM...DOODY/SIPPRELL SHORT TERM...SIPPRELL LONG TERM...RLG AVIATION...DOODY/RLG MARINE...RLG/SIPPRELL

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