Area Forecast Discussion
Issued by NWS Boston, MA

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000 FXUS61 KBOX 261426 AFDBOX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TAUNTON MA 1026 AM EDT WED AUG 26 2015 .SYNOPSIS... A COLD FRONT WILL LINGER NEAR THE COAST THIS AFTERNOON BEFORE FINALLY PUSHING OFFSHORE TONIGHT. HIGH PRESSURE SLOWLY BUILDS OVER THE REGION THROUGH THE END OF THE WORK WEEK BRINGING DRY AND SEASONABLE WEATHER. THE HIGH MOVES OFFSHORE BY NEXT WEEK ALLOWING FOR THE RETURN OF HOT...HUMIDITY AND HAZY WEATHER. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... COLD FRONT NEAR THE EASTERN MASS COASTLINE WILL MOVE EAST AND OFFSHORE THIS AFTERNOON. LINGERING HIGH MOISTURE OVER THE CAPE AND ISLANDS AHEAD OF THE FRONT...WITH APPROACHING UPPER TROUGH AND WITH SUPPORTING UPPER JET OVERHEAD. THIS MAY BE ENOUGH TO SET OFF A COUPLE OF SHOWERS/TSTMS OVER CAPE COD AND VICINITY BEFORE THE WIND SHIFT AND THE SLOW ARRIVAL OF DRIER DEW POINTS. WE NUDGED POPS BACK UP TO LOW-END CHANCE IN THIS AREA FOR THE EARLY AFTERNOON. OTHERWISE A FAIR WEATHER DAY WITH CLEARING SKIES AND LOWERING DEW POINTS. ALREADY COMFORTABLE LEVELS IN WESTERN SECTIONS...THIS WILL SPREAD EAST DURING THE AFTERNOON. TEMPS IN THE MIXED LAYER WILL SUPPORT MAX SFC TEMPS IN THE LOW TO MID 80S. NO CHANGES TO FORECAST MAX TEMPS. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/... TONIGHT... COLD FRONT PUSHES OFFSHORE WITH DRY CONDITIONS AND MOCLEAR SKIES. PATCHY INTERIOR VALLEY FOG POSSIBLE LATE AT NIGHT. DECENT RADIATIONAL COOLING WILL ALLOW LOW TEMPS TO DROP INTO THE 50S...EXCEPT LOW TO MID 60S BOS/PVD URBAN CENTERS AND CAPE/ACK. THURSDAY... MID LEVEL TROF AXIS SWINGS ACROSS NEW ENG BUT THE COLUMN IS DRY AS HIGH PRES BUILDS IN FROM THE WEST. THIS WILL LEAD TO MOSUNNY SKIES AND VERY PLEASANT CONDITIONS WITH COMFORTABLE HUMIDITY LEVELS. 850 MB TEMPS 10-11C SUPPORT MAXES MID 70S HIGHER TERRAIN TO NEAR 80 DEGREES COASTAL PLAIN AND INTERIOR VALLEYS. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... HIGHLIGHTS... * MAINLY DRY/SEASONABLE WITH COMFORTABLE HUMIDITY FRIDAY AND SAT * HAZY..HOT AND HUMID CONDITIONS LOOK TO RETURN NEXT WEEK OVERVIEW... 00Z GUIDANCE IS IN GOOD AGREEMENT FOR THIS PORTION OF THE FORECAST. THERE ARE SOME UNCERTAINTY WITH REGARDS TO THE STRENGTH OF A FEW PASSING SHORTWAVES BUT THIS SHOULD NOT IMPACT THE OVERALL TREND IN THE FORECAST. ZONAL FLOW ALOFT WILL ALLOW FOR A SHORTWAVE OR TWO TO MOVE THROUGH THE FLOW. THE GFS IS MORE PROGRESSIVE WHILE THE EC AMPLIFIES THE SHORTWAVES INTO A CUT-OFF LOW. REGARDLESS HIGH PRESSURE OVER NEW ENGLAND WILL BEGIN TO SHIFT OFFSHORE AS MID-LEVEL RIDGING BEGINS TO TAKE HOLD OVER THE NORTHEAST WELL INTO NEXT WEEK. DAILIES... THURSDAY NIGHT INTO SATURDAY...HIGH CONFIDENCE. HIGH PRESSURE WILL DOMINATE THE REGION ALLOWING FOR AVERAGE TEMPS AND LOW HUMIDITY. ASIDE FROM SEA BREEZES ALONG THE COASTLINES...HIGH TEMPS WILL BE IN THE UPPER 70S TO LOW 80S. OVERNIGHT LOWS WILL DROP INTO THE MID 50S TO LOW 60S. THIS IS A WELCOME RELIEF FROM THE OPPRESSIVE HEAT/HUMIDITY OVER THE PASS SEVERAL DAYS. SUNDAY AND BEYOND...LOW CONFIDENCE. GUIDANCE BEGINS TO DIVERGE DURING THIS PERIOD AS THERE ARE SOME UNCERTAINTIES ON THE STRENGTHS OF THE SHORTWAVES MOVING THROUGH THE FLOW. AS MENTIONED ABOVE THE DIFFERENCES BETWEEN THE GFS/EC...DECIDED TO GO AHEAD AN INSERT A SLIGHT CHC OF POP FOR THE WESTERN PORTION OF THE CWA FOR SUNDAY. THIS IS A LOW CONFIDENCE AND HOPE THAT THE GUIDANCE WILL BECOME BETTER ALIGN IN THE NEXT 24 HOURS. TEMPERATURES WILL BEGIN TO TREND ABOVE AVERAGE STARTING ON SUNDAY AND INTO THE FIRST WEEK OF SCHOOL FOR SOME. BOTH MODELS AND ENSEMBLES ARE HINTING AT ANOMALOUS UPPER LEVEL RIDGE TRYING TO BUILD. DEPENDING ON WHERE THE RIDGE SETS UP...WE COULD SEE EITHER U80S/L90S OR EVEN MID 90S FOR NEXT WEEK. IF THE GFS IS RIGHT...THEN THE POTENTIAL FOR BACK DOOR COLD FRONTS ARE POSSIBLE. WILL CONTINUE TO WATCH AS THIS IS AN IMPRESSIVE WARM SIGNAL FROM THE GUIDANCE. && .AVIATION /14Z WEDNESDAY THROUGH SUNDAY/... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /THROUGH THURSDAY/... THIS AFTERNOON...HIGH CONFIDENCE. VFR. BRIEF SHOWER OR TSTM POSSIBLE MIDDAY AND EARLY AFTERNOON CAPE COD AND ISLANDS. COASTAL SEABREEZES DEVELOPING. TONIGHT AND THURSDAY...HIGH CONFIDENCE. VFR. PATCHY IFR FOG LATE TONIGHT INTERIOR VALLEYS. KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. SEABREEZE LIKELY. ANOTHER SEABREEZE POSSIBLE THU BUT LOWER CONFIDENCE. KBDL TERMINAL...HIGH CONFIDENCE IN TAF. OUTLOOK /THURSDAY NIGHT THROUGH SUNDAY/...HIGH CONFIDENCE. FRIDAY THROUGH SATURDAY...VFR CONDITIONS. COULD SEE WEAK SEA BREEZES ALONG THE COASTLINES. SUNDAY...VFR CONDITIONS. LOW POTENTIAL FOR MVFR IN -SHRA ACROSS WESTERN MASS. && .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /THROUGH THURSDAY/...HIGH CONFIDENCE. QUIET BOATING WEATHER WITH WINDS AND SEAS BELOW SCA THRESHOLDS THROUGH THE PERIOD. A FEW SHOWERS OR PERHAPS A TSTM POSSIBLE EARLY AFTERNOON OVER EAST WATERS...OTHERWISE DRY WEATHER. OUTLOOK /THURSDAY NIGHT THROUGH SUNDAY/...HIGH CONFIDENCE. A PERIOD OF QUIET BOATING WEATHER IS EXPECTED THANKS TO BUILDING HIGH PRES. WINDS OUT OF THE W-NW THROUGH FRI...SHIFTING TO THE S BY SAT. WINDS AND SEAS BEGIN TO BUILD ON SUNDAY. WAVE GUIDANCE MAY BE A TAD HIGH BUT WILL NEED TO WATCH FOR POSSIBLE SCA. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...NONE. RI...NONE. MARINE...NONE. && $$ SYNOPSIS...KJC/DUNTEN NEAR TERM...WTB/KJC/DUNTEN SHORT TERM...KJC LONG TERM...DUNTEN AVIATION...WTB/KJC/DUNTEN MARINE...KJC/DUNTEN

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