Area Forecast Discussion
Issued by NWS Boston, MA

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000 FXUS61 KBOX 191431 AFDBOX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TAUNTON MA 931 AM EST WED NOV 19 2014 .SYNOPSIS... HIGH PRESSURE OVER THE REGION MOVES EAST TONIGHT...THEN A WEAK DISTURBANCE MAY BRING A FEW SNOW SHOWERS TO THE COASTAL PLAIN TONIGHT. ANOTHER SHOT OF UNSEASONABLY COLD AIR IS EXPECTED THURSDAY NIGHT INTO SATURDAY. A SIGNIFICANT WARM-UP IS IN STORE BY SUNDAY INTO EARLY NEXT WEEK. A STORM MOVING OUT OF TEXAS WILL LIKELY BRING RAIN TO SOUTHERN NEW ENGLAND SUNDAY NIGHT INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 7AM UPDATE... WEAK ARE OF HIGH PRES MOVES AWAY THIS MORNING AS CLIPPER APPROACHES FROM THE W. THEREFORE...IN SPITE OF THE CLEAR START MOST LOCATIONS EXPECT INCREASING CLOUDS..INCLUDING OCEAN EFFECT FOR CAPE/ISLANDS LATE IN THE DAY. FORECAST TRENDS SHOW THIS THINKING SO ADJUSTMENTS WERE MINIMAL WITH THIS AM UPDATE. PREVIOUS DISCUSSION... MID LEVEL TROF AXIS MOVES OFFSHORE THIS MORNING AS SFC RIDGE AXIS MOVES INTO SNE THEN TO THE EAST. RESULT WILL BE SUNSHINE AND GRADUALLY DIMINISHING WINDS BECOMING SOUTHWEST IN THE AFTERNOON. SOME INCREASE IN MID/HIGH CLOUDS EXPECTED LATER IN THE AFTERNOON. SOUNDINGS INDICATE MIXING TO AROUND 925 MB WHERE TEMPS -7/-8C. THIS SUPPORTS MAX TEMPS RANGING FROM UPPER 20S BERKSHIRES/MONADNOCKS TO MID 30S COASTAL PLAIN. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/... TONIGHT... CLIPPER LOW MOVES THROUGH THE GT LAKES WITH DECENT SHOT OF 850 MB WARM AIR ADVECTION DEVELOPING IN SNE AIDED BY 40-50 KT LOW LEVEL JET. MODELS INDICATE A RAPID INCREASE IN KI/TT VALUES TONIGHT COINCIDENT WITH THE LOW LEVEL JET AND DEEPENING MOISTURE PLUME MOVING INTO THE REGION SUGGESTING POTENTIAL FOR SOME SNOW SHOWERS. BEST CHANCE WILL BE ACROSS THE COASTAL PLAIN WHERE LOW LEVEL MOISTURE ADVECTION IS GREATEST AS SW FLOW WILL BRING IN HIGHER DEWPOINTS. VERY LIGHT QPF EVENT WITH ANY ACCUM A COATING TO LESS THAN AN INCH. WE HAVE CHC POPS ACROSS RI/SE MA WITH LOWER POPS ELSEWHERE. PTYPE LIKELY TRENDING MOSTLY RAIN FOR THE IMMEDIATE S COAST AND CAPE/ISLANDS DUE TO INCREASING SW WINDS OFF THE STILL MILD SST. EXPECT STEADY OR SLOWLY RISING TEMPS IN THE 30S NEAR THE SOUTH COAST WITH LOWS IN THE 20S FURTHER INLAND. BECOMING WINDY NEAR THE COAST WITH SW GUSTS TO 30 MPH AS GOOD MIXING IS ANTICIPATED GIVEN COLD LOW LEVEL TEMPS OVER MILDER WATER. THURSDAY... ANY SHOWER ACTIVITY SHOULD BE OFF THE COAST BY MORNING WITH CLOUDS NEAR THE COAST GIVING WAY TO MOSTLY SUNNY SKIES AS DECENT MID LEVEL DRYING MOVES IN. NEXT POTENT SHORTWAVE WILL BE DIVING THROUGH THE GT LAKES AND EXPECT MODERATING TEMPS AHEAD OF THE TROF WITH TEMPS REACHING INTO THE MID 40S COASTAL PLAIN...BUT MID/UPPER 30S DISTANT INTERIOR. GUSTY WEST WINDS TO 25-35 MPH EXPECTED...STRONGEST IN THE COASTAL PLAIN. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... HIGHLIGHTS... * ANOMALOUS COLD THROUGH SATURDAY * WARMER SUNDAY THROUGH END OF PERIOD * MAINLY RAIN LIKELY MONDAY OVERVIEW AND MODEL PREFERENCES... OPERATIONAL MODELS CONTINUE TO SHOW REASONABLY GOOD AGREEMENT THROUGH THE LONG TERM. THE LONGWAVE TROF ACROSS THE REGION WILL BEGIN A SLOW LIFT TOWARD THE EAST NORTHEAST AS INCOMING PACIFIC TROF FORCES RIDGE TO THE E. THIS PATTERN SHIFT IS WELL CAPTURED BY BOTH OPERATIONAL RUNS AND ENSEMBLES ALIKE...SO CONFIDENCE REMAINS RELATIVELY HIGH THAT A TRANSITION FROM BELOW NORMAL TEMPERATURES TO POSSIBLY EVEN ABOVE NORMAL IS EXPECTED OVER THE WEEKEND. WHILE THERE ARE SOME SLIGHT DIFFERENCES REGARDING THIS WAVE AND IT/S ATTENDANT COLD FRONT FOR SUN-MON...EVEN HERE A BLEND OF GUIDANCE CAPTURES THE PATTERN WELL. SUGGESTING A WARM INSIDE RUNNER. GIVEN THIS AGREEMENT...A GENERAL BLEND WILL BE USED FOR THIS UPDATE INCLUDING THE GFS/ECMWF AND SOME OF THE PREVIOUS FORECASTER. DETAILS... THU NIGHT INTO FRI NIGHT... ONE MORE REINFORCING SHOT OF COLD AIR EXPECTED EARLY FRI IN THE FORM OF A MODEST ARCTIC FRONT ATTENDANT TO THE KICKER WAVE WHICH WILL SHIFT THE PATTERN E. THEREFORE...FOR THIS PERIOD...EXPECT CONTINUED BELOW NORMAL TEMPERATURES. THE FRONT WILL ALSO INTRODUCE YET ANOTHER ROUND OF GUSTY W-NW WINDS YIELDING BLUSTERY CONDITIONS. SOUNDINGS LOOK MAINLY DRY...SO EXPECT MAINLY JUST SOME CLOUDS WITH THIS FRONTAL PASSAGE. SAT AND SUN... UPPER LVL SHIFT AS CUTOFF/LONGWAVE TROF SHIFTS TO THE E ALLOWING STACKED RETURN FLOW WITH GULF REGION CONNECTIONS. THEREFORE...AFTER A COOL START ON SAT...EXPECT TEMPS TO GRADUALLY INCREASE THROUGH SUN. WARM FRONT WILL BE APPROACHING AS OCCLUDING SYSTEM MOVES INTO THE GREAT LAKES REGION. AT THIS TIME...HANGING LOW-MID LVL RIDGE SHOULD KEEP MOST OF SRN NEW ENGLAND DRY WITH THE BULK OF OVERRUNING PRECIP ACROSS NRN NEW ENGLAND UNTIL COLD FRONTAL/OCCLUSION PRECIP APPROACHES LATE IN THE DAY. H85 TEMPS ON SUN SUGGEST HIGHS MAY ACTUALLY BE ABOVE NORMAL BY SUN IN SPITE OF INCREASING CLOUD COVER AND OVERALL COLUMN MOISTURE. SUN NIGHT INTO MON... WHAT LOOKS LIKE A WARM OCCLUSION WILL MOVE ACROSS THE REGION LATE SUN NIGHT INTO EARLY MON. DYNAMICS ARE FAIRLY ROBUST HERE...WITH POTENTIAL FOR 60 KT H85 LLJ. COMBINE THIS WITH 1.25 INCH PWATS /NEARLY 3 STD DEV ABOVE NORMAL/ AND SETUP SUGGESTS POTENTIAL FOR HEAVY RAIN WITH MODEST CONVECTIVE ELEMENTS. INDEED THE COLUMN LOOKS TO BE WARM ENOUGH FOR ALL RAIN BY THE TIME THIS PRECIP BEGINS. GIVEN THE STRONG DYNAMIC POTENTIAL FOR THIS SYSTEM...WILL HAVE TO MONITOR FOR PRECIP/WIND HEADLINES. A SECONDARY LOW PRES MAY ATTEMPT TO MAKE A NORTHWEST PASS ON MON...CONTINUING THE UNSETTELD WX...BUT THERE ARE SOME DISCREPANCIES REGARDING THE MOISTURE BY THIS POINT. TUE INTO WED... ALTHOUGH ANOTHER /ALBEIT LESS DEEP OR COLD/ TROF WILL ATTEMPT TO SETTLE ACROSS THE NRN CONUS INTO THE GREAT LAKES...A BLOCKING PATTERN SUGGESTS THE CORE OF THE COLD AIR MAY REMAIN TO THE W AT THIS TIME. && .AVIATION /15Z WEDNESDAY THROUGH SUNDAY/... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM...HIGH CONFIDENCE. TODAY... VFR. WEST WIND GUSTS TO 20-25 KT THROUGH ABOUT 15-17Z...DIMINISHING THEREAFTER. TONIGHT...MOSTLY VFR CIGS 6-10K FT DEVELOPING...BUT A PERIOD OF MVFR CIGS AND SCT SNOW SHOWERS POSSIBLE ACROSS RI AND SE MA WITH RAIN SHOWERS POSSIBLE OUTER CAPE/ISLANDS. INCREASING SW FLOW WITH GUSTS TO 25-30 KT DEVELOPING OVER THE CAPE/ISLANDS AND IMMEDIATE SOUTH COAST AFTER MIDNIGHT. THURSDAY...VFR. CIGS AROUND 5-6K FT NEAR THE COAST EARLY. W/SW GUSTS TO 20-30 KT. KBOS TERMINAL...HIGH CONFIDENCE. KBDL TERMINAL...HIGH CONFIDENCE. OUTLOOK...THURSDAY NIGHT THROUGH SUNDAY... FRIDAY AND SATURDAY...HIGH CONFIDENCE. MAINLY VFR. NW GUSTS POSSIBLE 20 TO 25 KTS ON FRI. LIGHTER WINDS SAT. SUNDAY...MODERATE CONFIDENCE. MAINLY VFR. SW WIND GUSTS INCREASE TO AROUND 25 KTS AGAIN. && .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. HIGH CONFIDENCE THROUGH THURSDAY. TODAY...FORECAST UPDATED TO BRING DOWN GALES ON THE EASTERN OUTER WATERS. WINDS WILL GRADUALLY DIMINISH BELOW 25 KT MIDDAY AND AFTERNOON. TONIGHT...SW LOW LEVEL JET WILL BRING ANOTHER PULSE OF GUSTY WINDS TO THE WATERS. DESPITE SW FLOW...COLD BOUNDARY LAYER OVER WARMER OCEAN WILL RESULT IN GOOD MIXING. HIGH CONFIDENCE FOR SCA WIND GUSTS AND MAY SEE MARGINAL GALE FORCE GUSTS DEVELOP OVER THE SOUTH COASTAL WATERS. THURSDAY...GUSTY W/SW WINDS WITH WIDESPREAD GUSTS TO 25-30 KT. NEAR GALE FORCE GUSTS TO 35 KT POSSIBLE OVER THE SOUTH COASTAL WATERS. OUTLOOK...THURSDAY NIGHT THROUGH SUNDAY... THU NIGHT INTO FRI...HIGH CONFIDENCE. WINDS AND SEAS REMAIN ABOVE SMALL CRAFT ADVISORY THRESHOLDS...WITH GUSTS APPROACHING 30 KT AND SHIFTING TO THE NW ON FRI. SEAS START AROUND 6-10 FT...BUT THEN GRADUALLY DIMINISH THROUGH THE PERIOD. SAT...HIGH CONFIDENCE. WINDS SHIFT TO THE W-SE BUT REMAIN BELOW SCA CRITERIA AND SEAS ALSO BELOW SCA THRESHOLDS. SUN...MODERATE CONFIDENCE. WINDS SHIFT TO THE S-SW...WITH GUSTS UP TO SMALL CRAFT ADVISORY THRESHOLDS AT LEAST...BUT MAY HAVE A FEW GALE FORCE GUSTS. SEAS INCREASE TO 5-7 FT ON THE OCEAN WATERS. && .CLIMATE... RECORD LOW MAX TEMPS TODAY... BOSTON 30/1897 PROVIDENCE33/1936 HARTFORD33/1955 WORCESTER29/2008 BLUE HILL27/1897 && .BOX WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...NONE. NH...NONE. RI...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR ANZ231>235-237-250-251-254>256. SMALL CRAFT ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR ANZ230. SMALL CRAFT ADVISORY UNTIL 10 AM EST THIS MORNING FOR ANZ236. && $$ SYNOPSIS...KJC/DOODY NEAR TERM...KJC/DOODY SHORT TERM...KJC LONG TERM...DOODY AVIATION...KJC/DOODY MARINE...WTB/KJC/DOODY CLIMATE...

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