Area Forecast Discussion
Issued by NWS Boston, MA

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000 FXUS61 KBOX 290636 AFDBOX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TAUNTON MA 236 AM EDT WED OCT 29 2014 .SYNOPSIS...
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A COLD FRONT WILL PUSH ACROSS THE REGION TODAY...BRINGING SCATTERED SHOWERS AND AN ISOLATED THUNDERSTORM OR TWO. THE FRONT WILL PUSH OFFSHORE THIS EVENING. WEAK HIGH PRESSURE WILL MOVE ACROSS THURSDAY AND FRIDAY WHICH WILL BRING DRY...COOL CONDITIONS. A DEVELOPING COASTAL STORM OFF THE CAROLINAS WILL PASS OFFSHORE SATURDAY NIGHT. HIGH PRESSURE BUILDS OVER THE EASTERN USA EARLY NEXT WEEK.
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&& .NEAR TERM /UNTIL 6 AM THIS MORNING/...
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2 AM UPDATE... WARM FRONT HAS PUSHED INTO CENTRAL NEW ENGLAND EARLY THIS MORNING. TEMPS RANGED FROM THE MID 40S ACROSS SW NH TO AROUND 60 ACROSS S COASTAL MA AT 05Z. NOTING TEMPS ARE SLOWLY RISING MAINLY ACROSS CENTRAL AND SOUTHERN AREAS...ALONG WITH DEWPTS. LOW CLOUDS HAVE DEVELOPED FROM NEAR KMHT-KORH-KIJD S AND E EXCEPT FOR THE IMMEDIATE S COAST...CAPE COD AND THE ISLANDS. LIGHT/VRBL OR CALM WINDS ACROSS MOST OF THE REGION...EXCEPT FOR SW WINDS AROUND 10 KT ALONG THE S COAST...CAPE COD AND THE ISLANDS. AT 03Z...COLD FRONT APPEARS TO BE CUTTING ACROSS CENTRAL NY/PA. LATEST NE REGIONAL MOSAIC RADAR SHOWING BROKEN LINE OF SHOWERS ALONG AND JUST AHEAD OF THE FRONT...WITH THE STEADIEST PRECIP SEEN ACROSS FAR N NY INTO NW VT. ONLY SPOTTY SHOWERS REPORTED IN THIS AREA...THOUGH. HAVE UPDATED FORECAST TO BRING CONDITIONS CURRENT...INCLUDING INCREASING CLOUD COVER AND ADJUSTED TEMPS TO NEAR TERM TRENDS. EVEN WITH A DRY FORECAST THROUGH THE REMAINDER OF THE NIGHT...CAN NOT RULE OUT SOME STRAY SPRINKLES WITH INCREASING HUMIDITY.
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&& .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM THURSDAY/...
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TODAY... COLD FRONT WILL SWEEP ACROSS THE REGION. SHOULD ENTER WESTERN REGIONS ABOUT 12Z AND MOVE OFFSHORE BY 03-06Z. THIS IS A SLOW MOVING SYSTEM BUT THERE IS A LACK OF DEEP LAYER MOISTURE SO THE POTENTIAL FOR FLOODING IS LOW. BELIEVE THAT THE SHOWERS WILL BE MORE SCATTERED IN NATURE AS IT PASSES THROUGH TOMORROW. HOWEVER GUIDANCE DOES HINT AT STEEP LAPSE RATES AND LI VALUES BELOW -2...ACROSS THE SOUTHEAST COASTAL PLAIN. THIS COMBINED WITH A 30-40 KT JUST OVERHEAD...CANNOT RULE OUT THE POTENTIAL FOR AN ISOLATED THUNDERSTORM AT THIS TIME. IF A THUNDERSTORM OR STRONG SHOWER DOES DEVELOP...THERE IS A POTENTIAL THAT IT CAN PULL DOWN SOME OF THE STRONGER AIR ALOFT. TEMPERATURES TOMORROW WILL BE SIMILAR TO TODAY...HOWEVER LOCATIONS OUT WEST MAY BE COOLER AS COLD FRONT PASSES THEM. EASTERN MASS AND RHODE ISLAND MAY SNEAK UP TO 70F BUT NOT MUCH HIGHER AS CLOUDS DURING THE DAY WILL LIMIT DIURNAL HEATING POTENTIAL. TONIGHT... UPPER LEVEL TROUGH WILL STILL BE MOVING OVERHEAD. THE COLD FRONT WILL EVENTUALLY PUSH OFFSHORE AROUND 06Z. THERE IS THE POTENTIAL THAT IT MAY LINGER A TAD LONGER SO HAVE KEPT A SLIGHT CHANCE OF PRECIP FOR THE CAPE AND ISLANDS. COLD AIR WILL BE USHERING IN BEHIND THE FRONT DUE TO CAA. SO ANTICIPATE A COOLER NIGHT WITH LOWS DROPPING INTO THE LOW TO MID 40S.
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&& .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... BIG PICTURE... UPPER TROUGH DIGS OVER THE EASTERN USA WHILE UPPER RIDGE MIGRATES FROM THE PACIFIC COAST TO THE PLAINS. THE TROUGH LINGERS OVER NEW ENGLAND THROUGH THE WEEKEND WITH BELOW NORMAL HEIGHTS IN PLACE. THE TROUGH THEN MOVES OFF THROUGH THE MARITIMES EARLY NEXT WEEK AS THE OVERALL FLOW BECOMES MORE ZONAL. THE ECMWF SEEMS A LITTLE MORE PROGRESSIVE THAN LAST RUN...BUT NO GUARANTEE THIS TREND WILL PERSIST. THE GFS AND ECMWF BRIEFLY FORM A CLOSED LOW OVER THE MIDWEST...THEN OPEN IT ALONG THE COAST. THE ECMWF BRINGS THE SURFACE LOW TO JUST OUTSIDE THE BENCHMARK WHILE THE GFS HOLDS IT FARTHER OFFSHORE. THE ECMWF IS A WETTER SOLUTION...THE GFS IS A COLDER SOLUTION. BOTH MODELS SHOW SIMILAR PROGRESS ON THE SHORTWAVE AXIS MOVING THROUGH THE OVERALL TROUGH. WE FAVORED AN EXPANDED BLEND OF GRID DATA...BLENDING THE 12Z ECMWF WITH OUR MODEL BLENDED FIELDS. EXPECT COOLER THAN NORMAL TEMPS FOR LATE WEEK AND THE WEEKEND...THEN A WARMING TREND FOR EARLY NEXT WEEK. THE DAILIES... THURSDAY-FRIDAY... COOLING ALOFT WITH WEAK RIDGING NEAR THE SURFACE. THIS SHOULD KEEP THE WEATHER DRY THURSDAY AND AT LEAST THE FIRST PART OF FRIDAY. AS THE SHORTWAVE DIVES INTO THE GREAT LAKES TROUGH AND TURNS THE UPPER FLOW OVER US MORE SOUTH-SOUTHWEST. MEANWHILE THE WEAK RIDGING BUILDS TO OUR NORTH AND TURNS OUR WIND EAST OR NORTHEAST. THIS WOULD MEAN INCREASED SKY COVER AND POSSIBLY A FEW SHOWERS LATE IN THE DAY AND AT NIGHT. MIXING ON THURSDAY SHOULD REACH TO AT LEAST 850 MB...WHERE TEMPS BETWEEN -1C AND +2C WOULD SUPPORT MAX TEMPS 55 TO 65. MIN TEMPS UPSTREAM SUPPORT THURSDAY NIGHT MIN TEMPS 35 TO 40...LOWER 40S ALONG THE COAST. CLOUDS AND A LIGHT NORTHEAST FLOW FRIDAY SHOULD KEEP TEMPS COOL...45 TO 55. SATURDAY-SUNDAY... AS NOTED ABOVE...UPPER TROUGH MOVES EAST FROM THE GREAT LAKES TO THE ATLANTIC COAST. UPPER JET FROM CENTRAL CANADA FEEDS AROUND THE UPPER TROUGH WITH LEFT EXIT REGION MOVING OVER THE CAROLINAS FRIDAY NIGHT/EARLY SATURDAY. THIS SUPPORTS THE IDEA OF A COASTAL LOW DEVELOPING. THE DEEP DIGGING UPPER TROUGH AND NEAR-SOUTH FLOW ALOFT WOULD SUGGEST A CLOSE-TO-THE-COAST TRACK A LA THE ECMWF. BUT WITH THE ECMWF TRENDING A LITTLE MORE PROGRESSIVE THAN LAST NIGHT THE TRACK FARTHER OFFSHORE IS STILL A POSSIBLE. CONFIDENT THAT THERE WILL BE UNSETTLED WEATHER THIS WEEKEND...WITH BEST CHANCE ALONG THE COASTAL PLAIN AND DIMINISHING POPS FARTHER NORTHWEST. WILL REFLECT THIS WITH LIKELY POPS SOUTHEAST GRADING TO CHANCE POPS NORTHWEST. GFS TRACK IS FARTHER OFFSHORE AND THEREFORE CLEARS SKIES FASTER. THE BLEND SHOULD SHOW MORE CLOUDS...AND MAY BE A LITTLE LESS COLD THAN A PURE GFS VALUE. LOW CONFIDENCE ON PTYPE. MUCH OF THE TIME SHOULD BE RAIN...BUT FIGURE WITH TEMPS FORECAST FALLING TO FREEZING OR BELOW WITH COLD AIR ALOFT THE RESULT WILL BE SOME SNOW ESPECIALLY IN THE NORTHWEST. ONE CHANGE FROM MODEL BLENDS...WE BUMPED WINDS UP 5-10 KNOTS REFLECTING 25 TO 35 KNOT WINDS ABOVE THE SURFACE SATURDAY AND 25 TO 40 KNOTS ON SUNDAY. HIGHEST WIND POTENTIAL WILL BE ALONG THE COAST. MONDAY-TUESDAY... HIGH PRESSURE BUILDS OVER THE REGION. LINGERING CLOUDS/COLD POOL ALOFT FROM THE DEPARTING UPPER LOW MAY KEEP SOME CLOUDS AROUND ESPECIALLY ON MONDAY. OTHERWISE FAIR AND DRY WITH TEMPS CLOSER TO NORMAL BY TUESDAY. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
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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 THURSDAY...MODERATE CONFIDENCE. THROUGH 12Z...MAINLY VFR. PATCHY MVFR-IFR CIGS/VSBYS WITH BRIEF LIFR IN LOCAL DENSE FOG...GENERALLY AWAY FROM THE S COAST FROM ABOUT KMHT-KORH-KIJD EAST. S-SW WINDS GUSTING TO AROUND 20 KT ALONG S COAST...CAPE COD AND THE ISLANDS. MAY SEE SCT SHOWERS APPROACH SW NH/NW MA AFTER 09Z. TODAY...MAINLY VFR. PATCHY MVFR CIGS/VSBYS IN SHOWERS. LOW PROB FOR ISOLD TSTM OR TWO FROM LATE MORNING THROUGH THE DAY NEAR OR AHEAD OF FRONT. S-SW WINDS GUSTING TO 20-25 KT MAINLY ALONG S COAST...CAPE COD AND THE ISLANDS. CONDITIONS IMPROVE ACROSS SW NH/W MA AFTER 18Z AS COLD FRONT SHIFTS E. TONIGHT...MAINLY VFR. MVFR CIGS/VSBYS ACROSS CENTRAL AND EASTERN AREAS THROUGH 03Z-05Z...THEN IMPROVING AS COLD FRONT PUSHES OFF COAST. SW WINDS GUSTING TO 20-25 KT EARLY TONIGHT ACROSS CAPE COD AND THE ISLANDS...THEN SHIFT TO W AND DIMINISH AFTER MIDNIGHT. LEFTOVER SCT SHOWERS MAY LINGER ACROSS CAPE AND ISLANDS THROUGH THE NIGHT. THURSDAY...VFR. PATCHY DIURNAL CLOUDS AT 4-5KFT ACROSS INTERIOR FROM LATE MORNING THROUGH THE AFTERNOON. KBOS...HIGH CONFIDENCE IN TAF. KBDL...HIGH CONFIDENCE IN TAF. LOW CONFIDENCE ON MVFR-IFR CONDITIONS IN LOW CLOUDS. OUTLOOK...THURSDAY THROUGH SUNDAY... THURSDAY-FRIDAY...HIGH CONFIDENCE. VFR. FRIDAY NIGHT THROUGH SUNDAY...LOW CONFIDENCE IN TIMING AND PRECIPITATION TYPE. MODERATE CONFIDENCE IN PRECIPITATION OCCURRENCE. CIGS/VSBYS LOWERING TO IFR COASTAL PLAIN AND MVFR NORTHWEST. COASTAL STORM PASSES LATER SATURDAY/SATURDAY NIGHT WITH A MIX OF RAIN AND SNOW ESPECIALLY MHT-ORH-BAF-BDL. PRECIPITATION TAPERS OFF ON SUNDAY. NORTH-NORTHEAST WINDS WITH GUSTS ALONG THE COAST 25-35 KNOTS SATURDAY. NORTHWEST WINDS SUNDAY WITH GUSTS 25 TO 30 KNOTS INLAND AND 30 TO 40 KNOTS ALONG THE COAST.
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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 WEDNESDAY NIGHT/...HIGH CONFIDENCE. OVERNIGHT...S-SW WINDS INCREASING AHEAD OF A COLD FRONT. ANTICIPATE GUSTS UP TO 25 KT ON THE SOUTHERN WATERS AND SEAS BUILDING. SMALL CRAFTS HAVE BEEN ISSUED. TODAY AND TONIGHT...EXPECT SW WINDS GUSTS BETWEEN 25 TO POSSIBLE 30KTS AND BUILDING SOUTHERN SEAS TO 6FT AHEAD OF AN APPROACHING COLD FRONT. THIS FRONT WILL CROSS THE WATERS DURING THE EVENING HOURS. BEHIND THE FRONT THE WIND WILL SWITCH TO THE WNW AND GUST UP TO 15 KTS...ALLOWING FOR SEAS TO RELAX. AS THE FRONT PASSES A FEW SHOWERS ARE POSSIBLE WHICH MAY REDUCE VSBYS. AN ISOLATED THUNDERSTORM CANNOT BE RULED OUT...WHICH COULD BRING GUSTS UP TO 30 KTS. OUTLOOK...THURSDAY THROUGH SUNDAY...MODERATE CONFIDENCE. THURSDAY AND FRIDAY...WEAK HIGH PRESSURE BUILDS NORTH OF THE WATERS. NORTHWEST WINDS THURSDAY BECOME NORTHEAST FRIDAY BUT REMAIN BELOW 20 KNOTS. SEAS LESS THAN 5 FEET. FRIDAY NIGHT THROUGH SUNDAY...COASTAL LOW PRESSURE DEVELOPS OFF THE CAROLINAS AND MOVES UP THE COAST. GREAT UNCERTAINTY IN THE EXACT TRACK. THE NEAREST FORECAST TRACK PASSES JUST OUTSIDE THE BENCHMARK...THE FARTHEST ONE PASSES PASSES ABOUT 400-500 MILES OUTSIDE THE BENCHMARK. AT LEAST MODERATE CONFIDENCE IN STRONG NORTH TO NORTHEAST WINDS WITH FREQUENT GUSTS SATURDAY 25 TO 35 KNOTS SHIFTING TO NORTHWEST 30 TO 40 KNOTS SUNDAY. A GALE WATCH/GALE WARNING MAY EVENTUALLY BE NEEDED DURING THE WEEKEND.
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&& .BOX WATCHES/WARNINGS/ADVISORIES...
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CT...NONE. MA...NONE. NH...NONE. RI...NONE. MARINE...SMALL CRAFT ADVISORY FROM 5 AM EARLY THIS MORNING TO 8 PM EDT THIS EVENING FOR ANZ231>234. SMALL CRAFT ADVISORY FROM 5 AM EARLY THIS MORNING TO 2 AM EDT THURSDAY FOR ANZ235-237. SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ250. SMALL CRAFT ADVISORY UNTIL 6 AM EDT THURSDAY FOR ANZ254>256.
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&& $$ SYNOPSIS...WTB/DUNTEN NEAR TERM...EVT SHORT TERM...DUNTEN LONG TERM...WTB AVIATION...WTB/EVT MARINE...WTB/EVT

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