Area Forecast Discussion
Issued by NWS Boston, MA

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000 FXUS61 KBOX 241614 AFDBOX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TAUNTON MA 1214 PM EDT THU APR 24 2014 .SYNOPSIS... WINDY AND DRY CONDITIONS TODAY...THEN WINDS DIMINISH TONIGHT AND FRIDAY AS HIGH PRESSURE BUILDS INTO THE REGION. LOW PRESSURE WILL BRING RAIN FRIDAY NIGHT INTO SATURDAY...THEN MAINLY DRY AND SEASONABLE CONDITIONS SUNDAY INTO MONDAY AS HIGH PRES RETURNS. && .NEAR TERM /UNTIL 6 PM THIS EVENING/...
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NOON UPDATE... DESPITE WIND SPEEDS REMAINING BELOW ADVISORY CRITERIA /40 KT/ GETTING NUMEROUS REPORTS OF DOWN TREE LIMBS. THUS HAVE HOISTED A WIND ADVISORY THRU 7 PM. STRONGEST LOW-MID LEVEL JET AND ACCOMPANYING PGRAD IS ACROSS EASTERN PORTIONS OF NEW ENGLAND. THEREFORE DID NOT INCLUDE WESTERN MA AND CT IN THE ADVISORY. ALSO EXCLUDED CAPE COD AND THE ISLANDS AS MIXED LAYER NOT AS DEEP HERE GIVEN TRAJECTORY ACROSS THE NEAR SHORE WATERS TO THE ISLANDS. PREVIOUS DISCUSSION BELOW. ----------------------------------------------------------------- EARLIER FORECAST ON TRACK WITH CURRENT CONDITIONS. THUS NO MAJOR CHANGES EXPECTED. ABUNDANT APRIL SUNSHINE WILL BE OFFSET BY COLD AIR ADVECTION ON GUSTY NW WINDS. 12Z OBSERVED SOUNDING FROM ALBANY NY HAS -4C TEMPS AT 850 MB. THIS SUPPORTS HIGHS IN THE LOW 50S BUT GIVEN BLYR WILL EXTEND BEYOND 850 MB ALONG WITH DOWNSLOPING WINDS...TEMPS THIS AFTERNOON SHOULD CLIMB INTO THE MU50S AND NEAR 60 IN THE COASTAL PLAIN INCLUDING BOSTON TO PROVIDENCE. NO WIND HEADLINES AS PREVIOUS SHIFT MENTIONED AS WIND GUSTS SHOULD REMAIN BELOW 46 MPH. EARLIER DISCUSSION BELOW.
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&& .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/... TONIGHT... GUSTY WINDS LINGERING INTO THE EVENING...THEN WINDS DIMINISH AS PRESSURE GRADIENT RELAXES WITH HIGH PRES APPROACHING FROM THE WEST. CLEAR SKIES AND DIMINISHING WIND WILL RESULT IN A COLD NIGHT WITH MINS MID 20S TO LOWER 30S ACROSS MUCH OF THE REGION...EXCEPT UPPER 30S BOS/PVD AND OUTER CAPE/ISLANDS. FRIDAY... HIGH PRES MOVES ACROSS NEW ENG THEN TO THE EAST BY DAYS END. NEXT SHORTWAVE WILL BE LIFTING NE FROM THE OHIO VALLEY WHICH WILL RESULT IN AN INCREASE IN MID/HIGH CLOUDS IN THE AFTERNOON FROM THE WEST. IT WILL REMAIN DRY AS DEEP MOISTURE TRANSPORT ASSOCD WITH THE LOW LEVEL JET REMAINS TO THE WEST THROUGH 00Z. IT WILL BE A MILDER DAY IN DEVELOPING WARM AIR ADVECTION PATTERN. SOUNDINGS SHOW MIXING TO 850 MB WHERE TEMPS INCREASE TO 2-3C AROUND 18Z. THIS SUPPORTS TEMPS INTO THE LOW AND MID 60S...BUT 50S ALONG THE S COAST DUE TO SOUTHERLY WIND. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... HIGHLIGHTS... * UNSETTLED BUT SEASONABLE WEATHER FRIDAY NIGHT INTO SATURDAY * UNCERTAINTY HIGHER THAN NORMAL FOR NEXT WEEK 24/00Z MODELS ARE IN DECENT AGREEMENT THROUGH MUCH OF THE LONG TERM. THERE ARE OF COURSE SOME DISCREPANCIES TOWARDS THE END OF THE PERIOD. A DOUBLE BARRELED LOW PRESSURE SYSTEM WILL AFFECT SOUTHERN NEW ENGLAND FRIDAY NIGHT AND SATURDAY WITH SOME UNCERTAINTY IN HOW CLOSE THE SOUTHERN LOW MOVES TO THE SOUTHERN NEW ENGLAND COAST. THE ECMWF IS FARTHEST FROM THE COAST...PASSING OVER THE 40/70 BENCHMARK AND THE NAM IS CLOSEST PASSING OVER NANTUCKET. THE ECMWF HAS TRENDED NORTH SINCE THE 12Z RUN SO WENT WITH A NAM/GFS BLEND FOR THIS PORTION OF THE FORECAST. BEYOND THIS...MODELS ARE STRUGGLING WITH A DEVELOPING BLOCKING PATTERN. MODELS ARE QUICK TO MOVE TOWARDS A MORE PROGRESSIVE PATTERN. ENSEMBLES SHOW THE BLOCKING PATTERN A BIT BETTER THOUGH THERE ARE DIFFERENCES AMONGST THE MEMBERS AS TO WHETHER WE WILL BE MORE INFLUENCED BY RIDGING OR TROUGHING. BETWEEN THIS AND THE MODELS TENDENCY TO RUSH A RETURN TO A MORE PROGRESSIVE PATTERN...HAVE A LOWER CONFIDENCE THAN NORMAL FOR NEXT WEEK. FRIDAY NIGHT AND SATURDAY...DOUBLE BARREL LOW PRESSURE MOVES EAST ACROSS SOUTHERN NEW ENGLAND. THE NORTHERN LOW MOVES THROUGH QUEBEC WHILE THE SOUTHERN LOW PASSES SOUTH OF SOUTHERN NEW ENGLAND. THE ECMWF IS THE FARTHEST SOUTH WITH THE SOUTHERN LOW WHILE THE NAM IS THE FARTHEST NORTH. EXPECT SCATTERED SHOWERS ACROSS SOUTHERN NEW ENGLAND WITH THIS SYSTEM. STEEP MID LEVEL RATES PROVIDE ENOUGH INSTABILITY FOR THUNDERSTORMS TO OCCUR AND AS SUCH HAVE MENTIONED THUNDER IN THE GRIDS. SUNDAY INTO EARLY NEXT WEEK...AS STATED ABOVE A MORE BLOCKED PATTERN LOOKS TO DEVELOP WITH MID LEVEL TROUGHING OVER THE NE BRINGING UNSETTLED WEATHER TO THE REGION. WHERE EXACTLY THE BLOCKED PATTERN SETS UP WILL DETERMINE WHAT SORT OF WEATHER WE ARE LOOKING AT. SOME MODELS HAVE A PRONOUNCED EASTERLY FLOW WHICH WOULD RESULT IN UNSEASONABLY COOL TEMPERATURES AND OVERCAST SKIES ACROSS MUCH OF THE AREA. HOWEVER...A SHIFT COULD RESULT IN MORE SEASONABLE WEATHER. && .AVIATION /16Z THURSDAY THROUGH MONDAY/... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /THROUGH FRIDAY/...HIGH CONFIDENCE 10 AM UPDATE... NO CHANGES FROM 12Z TAFS. CONFIDENCE REMAINS HIGH IN DRY RUNWAYS/VFR AND GUSTY NW WINDS. EARLIER DISCUSSION BELOW. -------------------------------------------------------- VFR THROUGH THE PERIOD. MAIN CONCERN WILL BE GUSTY NW WINDS TODAY AS GUSTS TO 35-40 KT EXPECTED. WINDS WILL GRADUALLY DIMINISH TONIGHT WITH LIGHT WINDS FRIDAY. KBOS TERMINAL...HIGH CONFIDENCE IN TAF. KBDL TERMINAL...HIGH CONFIDENCE IN TAF. OUTLOOK...FRIDAY NIGHT THROUGH MONDAY... FRIDAY NIGHT AND SATURDAY...MODERATE CONFIDENCE. MAINLY VFR. BRIEF PERIODS OF MVFR/IFR CONDITIONS IN RAIN SHOWERS/FOG. SUNDAY AND MONDAY...LOW CONFIDENCE. VFR. && .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /THROUGH FRIDAY/...HIGH CONFIDENCE. 10 AM UPDATE... NO MAJOR CHANGES FROM PREVIOUS FORECAST. STRONGEST WINDS NEAR SHORE GIVEN WARMER LAND TEMPS /55-60/ THAN OCEAN TEMPS /LOW 40S/. EARLIER DISCUSSION BELOW. --------------------------------------------------------------- NW GALES EXPECTED THROUGH TODAY WITH GUSTS TO 35-40 KT. WINDS DIMINISH THROUGH TONIGHT AS GRADIENT RELAXES WITH LIGHT WINDS ON FRIDAY AS HIGH PRES MOVES ACROSS THE WATERS. OUTLOOK...FRIDAY NIGHT THROUGH MONDAY... FRIDAY NIGHT AND SATURDAY...LOW TO MODERATE CONFIDENCE. S WINDS AND SEAS INCREASE AS A COLD FRONT APPROACHES THE WATERS. VISIBILITIES MAY BE REDUCED AT TIMES IN RAIN SHOWERS. SMALL CRAFT ADVISORIES MAY BE NECESSARY ON THE OUTER WATERS. WINDS SHIFT TO THE NW AS THE COLD FRONT CROSSES THE WATERS. SUNDAY AND MONDAY...MODERATE CONFIDENCE. N/NW WINDS AND SEAS GENERALLY REMAIN BELOW SMALL CRAFT CRITERIA BUT CONDITIONS ARE CLOSE. SMALL CRAFT ADVISORIES MAY BE NEEDED. && .FIRE WEATHER... 10 AM UPDATE... NO MAJOR CHANGES FROM EARLIER DISCUSSION. PREVIOUS FORECAST MATCHING UP NICELY WITH CURRENT CONDITIONS. ----------------------------------------------------------- CONDITIONS TODAY ARE FAVORABLE FOR FIRE WEATHER HEADLINES WITH MIN RH 15-25 PERCENT AND STRONG WIND GUSTS TO 40 MPH. HOWEVER...RECENT RAINFALL IN CENTRAL AND EASTERN NEW ENG WILL PRECLUDE RED FLAG CONDITIONS IN THESE AREAS. HOWEVER...LESS RAINFALL OCCURRED IN THE CT VALLEY AND AFTER COLLABORATION WITH OKX/ALY WE HAVE DECIDED TO ISSUE A RED FLAG WARNING FOR N CT. && .BOX WATCHES/WARNINGS/ADVISORIES...
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CT...RED FLAG WARNING UNTIL 8 PM EDT THIS EVENING FOR CTZ002>004. MA...WIND ADVISORY UNTIL 7 PM EDT THIS EVENING FOR MAZ004>007- 012>021-026. NH...WIND ADVISORY UNTIL 7 PM EDT THIS EVENING FOR NHZ011-012-015. RI...WIND ADVISORY UNTIL 7 PM EDT THIS EVENING FOR RIZ001>007. MARINE...GALE WARNING UNTIL 8 PM EDT THIS EVENING FOR ANZ230>237-250- 251-254>256.
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&& $$ SYNOPSIS...KJC/RLG NEAR TERM...KJC/NOCERA/RLG SHORT TERM...KJC LONG TERM...RLG AVIATION...KJC/NOCERA/RLG MARINE...NOCERA/RLG FIRE WEATHER...

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