Area Forecast Discussion
Issued by NWS Boston, MA

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000 FXUS61 KBOX 242025 AFDBOX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TAUNTON MA 425 PM EDT SUN MAY 24 2015 .SYNOPSIS...
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A WARM FRONT WILL MOVE ACROSS THE REGION MONDAY FOLLOWED BY WARM AND HUMID CONDITIONS WHICH WILL LIKELY LAST INTO NEXT WEEKEND. THE THREAT FOR SCATTERED SHOWERS AND THUNDERSTORMS WILL INCREASE FROM WEDNESDAY AFTERNOON INTO THE WEEKEND.
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&& .NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
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THROUGH 00Z... BAND OF HIGH CLOUDS SPREADING ACROSS THE REGION WELL AHEAD OF APPROACHING WARM FRONT OUT OF THE GREAT LAKES REGION. CLOSEST PRECIP ASSOCIATED WITH SHORT WAVE MOVING ACROSS N VT/CENTRAL NH AT 20Z BUT HEADING SE OFF THE ME COAST. EXPECT THE HIGH CLOUDS TO THICKEN A BIT INTO THIS EVENING...WHILE ANOTHER BATCH OF MID AND HIGH LEVEL CLOUDS BEGIN TO APPROACH FROM THE W. SW WIND GUSTS UP TO 20-25 MPH WILL BE DIMINISHING THIS EVENING. TONIGHT... AN AREA OF MID AND HIGH LEVEL CLOUDS WILL WORK E OUT OF NY STATE TONIGHT...REACHING INTO CENTRAL AND WESTERN AREAS. GOOD SUBSIDENCE REMAINS IN PLACE WITH HIGH PRES OFF THE MID ATLC COAST AND RIDGING INLAND TO THE TENNESSEE VALLEY WHICH WILL KEEP ANY APPRECIABLE MOISTURE WELL W OF THE REGION. SW WINDS WILL REMAIN IN PLACE...WHICH WILL ALLOW DEWPTS TO SLOWLY RISE. WILL BE A MILD NIGHT WITH LOWS ONLY DROPPING TO THE 50S. MAY SEE SOME PATCHY FOG ALONG PORTIONS OF THE IMMEDIATE S COAST...CAPE COD AND THE ISLANDS LATE TONIGHT.
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&& .SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
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MONDAY AND MONDAY NIGHT... BERMUDA HIGH SETS UP ALONG EASTERN SEABOARD. WARM FRONT DEVELOPS AS IT SHIFTS E ACROSS NY STATE DURING MONDAY. HOWEVER...WITH STRONG SUBSIDENCE IN PLACE AS WELL AS CONTINUED SW SURFACE WINDS AND H5 RIDGING BUILDING ACROSS WESTERN NEW ENGLAND...BETTER MOISTURE AND LIFT WILL REMAIN N AND W OF THE REGION. WHILE THERE WILL BE NO PRECIP WITH THIS FRONT...WILL SEE A LOT OF CLOUDINESS STREAMING ACROSS THE REGION. EXPECT THE WARM FRONT TO PUSH NE ACROSS NORTHERN NEW ENGLAND MON NIGHT. MAY SEE SOME LEFTOVER PATCHY FOG ALONG THE S COAST EARLY MON MORNING...THEN AGAIN NEAR THE S COAST AS WELL AS OUTER CAPE COD AND THE ISLANDS LATE MON NIGHT AS DEWPTS/RH VALUES INCREASE. EVEN WITH THE CLOUDS...IT WILL STILL BE WARM ON MON WITH HIGHS AROUND 80 EXCEPT IN THE UPPER 60S AND 70S ACROSS S COASTAL AREAS. READINGS WILL ONLY FALL BACK TO THE UPPER 50S TO LOWER 60S MON NIGHT...AND IT WILL BE MUGGY AS DEWPTS CONTINUE TO RISE THROUGH THE 50S.
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&& .LONG TERM /TUESDAY THROUGH SUNDAY/... HIGHLIGHTS... * WARM AND HUMID INTO THE WEEKEND * INCREASING SHOWER/THUNDERSTORM POTENTIAL WED INTO THU * MORE SHOWERS AND THUNDERSTORMS POSSIBLE THIS WEEKEND OVERVIEW... MID LEVEL RIDGING ALONG THE EAST COAST WILL BE THE DOMINANT FEATURE THROUGH MUCH OF THE WEEK...ALTHOUGH NORTHERN STREAM ENERGY RIDING OVER THE TOP WILL DEAMPLIFY THE RIDGE ALLOWING FOR A WEAK FROPA AROUND THU TIMEFRAME. ABOVE NORMAL TEMPS WITH INCREASING HUMIDITY WILL BE THE THEME THROUGH THE WEEK WITH THE WARMEST TEMPS TUE/WED...WITH POTENTIAL FOR NEAR 90 DEGREES INTERIOR VALLEYS. BEST CHANCE FOR SHOWERS/TSTMS WILL BE THU WITH THE FROPA...BUT NEARBY INSTABILITY AXIS SUGGESTS POTENTIAL FOR SCT CONVECTION FOR INTERIOR LOCATIONS ON WED/FRI. LOOKING AHEAD TO THE WEEKEND...A MORE ROBUST MID LEVEL TROF WILL BE SLIDING EAST ACROSS SE CANADA BUT MODELS DIFFER ON TIMING WHICH WILL AFFECT TIMING OF A COLD FRONT AND SENSIBLE WEATHER. WE LEANED TOWARD WPC GUIDANCE WHICH IS CLOSER TO SLOWER ECMWF. TUESDAY INTO WEDNESDAY... SNE IN THE WARM SECTOR AIRMASS WITH SW FLOW BRINGING WARM AND INCREASINGLY HUMID CONDITIONS. 850 MB TEMPS 15-16C SUGGEST POTENTIAL FOR NEAR 90 DEGREES IN SOME OF THE INTERIOR VALLEYS...BUT SW WINDS OFF COOLER OCEAN WILL KEEP TEMPS IN THE 70S NEAR THE SOUTH COAST. DEWPOINTS CLIMBING TO 60+ SO IT WILL START TO FEEL A BIT HUMID COMPARED TO RECENT DAYS. REGARDING TSTM POTENTIAL...THINK TUE WILL BE MOSTLY DRY WITH POSSIBLE EXCEPTION OF FAR W NEW ENG AS MODELS GENERATE SOME MARGINAL INSTABILITY DURING THE AFTERNOON WITH SBCAPES AROUND 500 J/KG AND KI CLIMBING TO 30+. CANT RULE OUT AN ISOLD TSTM ACROSS W ZONES DURING THE AFTERNOON/EVENING...OTHERWISE MAINLY DRY TUE. MORE INSTABILITY IS FORECAST ON WEDNESDAY WITH CAPES EXCEEDING 1000 J/KG SO EXPECT SCT AFTERNOON SHOWERS/TSTMS DEVELOPING...MAINLY CONFINED TO W ZONES WHERE BEST INSTABILITY. 0-6KM SHEAR IS WEAK...LESS THAN 25 KT SO MAIN THREAT IS LOCALLY HEAVY RAINFALL GIVEN HIGH PWATS. THURSDAY AND FRIDAY... NOT MUCH CHANGE IN AIRMASS WITH CONTINUED THREAT OF SHOWERS/TSTMS...MAINLY INTERIOR. IT APPEARS BEST CHANCE OF CONVECTION WILL BE THU AS SHORTWAVE PASSES TO THE NORTH WITH SUBTLE MID LEVEL COOLING AND WEAK FROPA MOVING INTO THE REGION. CAPES 1000+ J/KG AND SOME CONVERGENCE SUGGESTS A MORE ACTIVE DAY AND 0-6KM SHEAR IS A BIT STRONGER AS WELL BUT STILL LESS THAN 30 KT. HEAVY RAIN IS MAIN THREAT BUT A FEW STRONG TO SEVERE STORMS POSSIBLE THU. TEMPS ABOVE NORMAL...WARMEST 80S IN THE INTERIOR. SATURDAY AND SUNDAY... GFS IS CONSIDERABLY FASTER THAN ECMWF WITH COLD FRONT WITH SHOWERS/TSTMS SAT THEN DRYING OUT SUNDAY AS HIGH PRES BUILDS TO THE N. ECMWF HAS FRONT MOVING THROUGH SUN AFTERNOON/EVENING WITH BEST CHANCE OF CONVECTION DURING THIS TIME. WPC CONSENSUS FAVORED LOWER SOLUTION. A LOW CONFIDENCE FORECAST AT THIS TIME RANGE AND TIMING OF FRONT WILL DICTATE WHICH WEEKEND DAY HAS BETTER CHANCE OF CONVECTION. && .AVIATION /20Z SUNDAY THROUGH FRIDAY/...
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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 MONDAY NIGHT/...HIGH CONFIDENCE. THROUGH TONIGHT...VFR. W-SW WIND GUSTS UP TO 25 KT THROUGH 00Z-02Z MAINLY NEAR COASTAL TERMINALS. CIGS AOA 8KFT AFTER 03Z THROUGH THE NIGHT. MAY SEE PATCHY FOG WITH MVFR TO LOCAL IFR VSBYS AFTER 06Z MAINLY ACROSS THE ISLANDS...POSSIBLY UP TO THE IMMEDIATE S COAST. MONDAY AND MONDAY NIGHT...VFR. MAY SEE PATCHY FOG WITH MVFR VSBYS EARLY MON MORNING AND AGAIN AFTER MIDNIGHT MON NIGHT...MAINLY NEAR THE S COAST AND OUTER CAPE COD/NANTUCKET. SW WINDS INCREASE MON NIGHT...GUSTING TO 20-25 KT. KBOS TERMINAL...HIGH CONFIDENCE IN TAF. KBDL TERMINAL...HIGH CONFIDENCE IN TAF. OUTLOOK...TUESDAY THROUGH FRIDAY...MODERATE CONFIDENCE. MOSTLY VFR CIGS. BUT BRIEF MVFR/IFR IN ANY SHOWERS/THUNDERSTORMS WED THROUGH FRIDAY. LOW CONFIDENCE ON DURATION AND AREAL EXTENT OF ANY IFR STRATUS AND FOG DURING THE LATE NIGHT AND MORNING PERIODS. SW GUSTS TO 25 KT ALONG SE NEW ENG COAST TUE/WED.
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&& .MARINE...
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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 MONDAY NIGHT/...HIGH CONFIDENCE. THROUGH TONIGHT...HAVE EXTENDED SMALL CRAFTS OVER THE OUTER WATERS THROUGH 06Z AS GUSTS AND 5 FT SEAS LINGER THERE. WINDS/SEAS WILL DIMINISH...FIRST AT BOSTON HARBOR/NARRAGANSETT BAY EARLY THIS EVENING /23Z/...THEN ACROSS THE REMAINING NEAR SHORE LOCATIONS. MAY SEE PATCHY FOG DEVELOP LATE TONIGHT ACROSS PORTIONS OF THE SOUTHERN WATERS WITH REDUCED VSBYS. MONDAY-MONDAY NIGHT...SW WINDS CONTINUE...GUSTING UP TO 20 KT DURING MON. SEAS SHOULD REMAIN BELOW 5 FT DURING THE DAY. EXPECT SW WIND GUSTS TO PICK UP TO 20-25 KT MON NIGHT. SEAS ALSO BUILD TO 5-6 FT ON THE SOUTHERN WATERS AS WELL AS THE EASTERN OUTER WATERS. OUTLOOK...TUESDAY THROUGH FRIDAY...MODERATE CONFIDENCE. PERSISTENT SW FLOW WITH GUSTS AROUND 20-25 KTS AT TIMES. STRONGEST WINDS OVER THE NEARSHORE WATERS. INCREASING SWELL AND WIND WAVE WILL RESULT IN SEAS BUILDING TO 5-6 FT OVER S COASTAL WATERS. FOG ANTICIPATED DURING THE OVERNIGHT AND MORNING LENDING TO VISIBILITY RESTRICTIONS.
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&& .FIRE WEATHER...
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4 PM UPDATE... EXPECT DEWPTS TO SLOWLY BUT STEADILY RISE TONIGHT AND MONDAY WITH PERSISTENT SW WINDS IN PLACE. FORECASTED MINIMUM RH VALUES WILL BE FROM 35 TO 60 PERCENT ON MONDAY...LOWEST ACROSS INTERIOR AREAS. WITH THE INCREASING HUMIDITY...EXPECT LOWERED FIRE WEATHER RISK SO WILL NOT BE ISSUING A STATEMENT AT THIS TIME.
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&& .BOX WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...NONE. RI...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR ANZ231>235-237-251. SMALL CRAFT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR ANZ230- 236. SMALL CRAFT ADVISORY UNTIL 2 AM EDT MONDAY FOR ANZ250-254. SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR ANZ255- 256. && $$ SYNOPSIS...KJC/EVT NEAR TERM...EVT SHORT TERM...EVT LONG TERM...KJC AVIATION...KJC/EVT MARINE...KJC/EVT FIRE WEATHER...EVT

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