Area Forecast Discussion
Issued by NWS Boston, MA

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000 FXUS61 KBOX 111735 AFDBOX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TAUNTON MA 135 PM EDT FRI APR 11 2014 .SYNOPSIS... A WEAK COLD FRONT WILL MOVE ACROSS NEW ENGLAND TODAY AND STALL ALONG THE SOUTH COAST TONIGHT...BRINGING A FEW SHOWERS AS WEAK LOW PRESSURE PASSES SOUTH OF THE REGION. DRY AND PROGRESSIVELY MILDER CONDITIONS ARE EXPECTED OVER THE WEEKEND AND MON. A SLOW MOVING FRONT WILL BRING A SOAKING RAIN SOMETIME TUE AND WED. && .NEAR TERM /UNTIL 6 PM THIS EVENING/...
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135 PM UPDATE... WATCHING BATCH OF SHOWERS MOVING NE FROM PA AND UPSTATE NY WHICH WILL REACH CT VALLEY 3-4 PM AND E COAST CLOSER TO 5-6 PM. HIGH-RES MODELS HAVE A DECENT HANDLE ON SITUATION AND WERE FOLLOWED CLOSELY FOR POPS THROUGH EARLY TONIGHT. MAIN IDEA IS MOST OF SHOWERS FOCUS JUST ON COOL SIDE OF FRONT ACROSS INTERIOR LATE THIS AFTERNOON AND EVENING BEFORE SHIFTING SE. DESPITE PLENTY OF MID/HIGH CLOUDS...SOUTHERLY FLOW HAS ALLOWED TEMPERATURES TO RISE WELL INTO 60S AWAY FROM S COAST. A FEW SPOTS MAY TOUCH 70 THIS AFTERNOON. STILL ANTICIPATE WEAK SEA BREEZE ALONG E MA COAST LATER THIS AFTERNOON AS GRADIENT WEAKENS AHEAD OF FRONT.
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&& .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/... TONIGHT... UPPER SHORTWAVE MOVES FROM THE GREAT LAKES THIS EVENING TO NEW ENGLAND BY SUNRISE SATURDAY. UPPER JET SUPPORTING THE SHORTWAVE MOVES ACROSS NEW ENGLAND OVERNIGHT WITH SOUTHERN NEW ENGLAND IN THE RIGHT ENTRANCE REGION OF THE JET. THIS WILL GENERATE UPPER VENTING OVER OUR AREA AND ESPECIALLY OVER THE STALLED COLD FRONT...AND HELP GENERATE A WAVE OF LOW PRESSURE ALONG THE FRONT. SUFFICIENT LIFT AND MOISTURE TO GENERATE RAIN/SHOWERS ACROSS OUR AREA WITH PREFERENCE FOR CT/RI/SE MASS. HIGHEST POPS WILL BE IN THE VICINITY OF THE STALLED FRONT WITH MAX VALUES 60-65 PCT. THE WAVE AND ITS UPPER SUPPORT MOVE EAST OF CAPE COD BY 12Z...SO POPS SHOULD BE DIMINISHING BY THAT TIME. SATURDAY... HIGH PRESSURE BUILDS OVER THE REGION BRINGING CLEARING AND DRY WEATHER. MIXING SHOULD REACH TO 850 MB...WHERE TEMPS WILL BE AROUND 3C. THIS SHOULD SUPPORT MAX TEMPS IN THE LOW TO MID 60S. EVEN A DEEPER MIXING TO 800 MB WOULD SUPPORT MID 60S. WIND FIELDS WILL BE LIGHT...WHICH WOULD ALLOW SEABREEZES TO DEVELOP NEAR THE COASTS. TEMPS IN THESE AREAS SHOULD BE IN THE UPPER 40S AND 50S. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... HIGHLIGHTS... * ABOVE AVERAGE TEMPERATURES ARE EXPECTED ON SUNDAY/MONDAY * STRONG COLD FRONTAL PASSAGE NEXT TUES/WED * BELOW AVERAGE TEMPERATURES RETURN FOR THE REMAINDER OF THE WORK WEEK MODELS AND CONFIDENCE... HAVE HIGH CONFIDENCE IN THE WARMING TREND IN THE FORECAST OVER THE WEEKEND WITH A MODERATE CONFIDENCE FOR THE TIMING POTENTIAL FOR THE SYSTEM NEXT WEEK. INCREASING CONFIDENCE THAT PRECIP WILL OCCUR OVER THE MID-WEEK SYSTEM BUT THE EXACT TIMING AND LOCATION OF MODERATE RAINFALL ARE STILL UNCERTAIN. FINALLY BELIEVE THAT TEMPS WILL DROP BELOW AVERAGE BY WEDNESDAY/THURSDAY. STILL SOME UNCERTAINTY LEADING UP TO NEXT WEEK AS STRONG TROUGH DIGS TOWARDS THE NORTHEAST. OVERALL 00Z MODEL GUIDANCE IS IN GOOD AGREEMENT. THE RE- AMPLIFICATION OF THE UPPER PATTERN WILL TAKE SHAPE LATE THIS WEEKEND INTO NEXT WEEK. UPPER RIDGING WILL BUILD OVER SE ALASKA/NW CANADA AS WELL AS ACROSS THE NORTHEAST...FAVORING DIGGING TROUGHING OVER THE CENTRAL CONUS. THIS WILL SUPPORT A STRENGTHENING SURFACE FRONTAL BOUNDARY THAT WILL SLOWLY MARCH EASTWARD TOWARDS NEW ENGLAND BY TUES/WED. THE DETERMINISTIC AND ENSEMBLE GUIDANCE CONTINUE TO SHOW BETTER AGREEMENT ON THE EVOLUTION OF THIS SYSTEM...WITH BOTH THE DETERMINISTIC GFS/EC IN GOOD AGREEMENT. IN THE WAKE OF THIS FRONT HIGH PRESSURE SHOULD SETTLE OVER/NEAR NEW ENGLAND WITH ENOUGH GRADIENT SURROUNDING IT TO SUPPORT BREEZY CONDS AWAY FROM THE HIGH CENTER. TEMPS SHOULD MODERATE TO WITHIN 10F OF NORMAL BY LATE NEXT WEEK. HAVE TRENDED THIS FORECAST TOWARDS PREVIOUS FORECAST AND WPC. DETAILS... SATURDAY NIGHT INTO MONDAY... HIGH PRESSURE WILL EXIT OFFSHORE BY SUNDAY MORNING AS A FRONTAL SYSTEM TO THE NORTH OF THE REGION BEGINS TO MOVE TOWARDS SOUTHERN NEW ENGLAND. THIS FRONT WILL STALL BEFORE REACHING SOUTHERN NH AND THEN MOVE NORTHWARD BY MONDAY AS A WARM FRONT. RETURN FLOW TO THE REGION WILL ALLOW FOR GOOD WAA ON BOTH SUNDAY AND MONDAY. DURING THE DAY...A GOOD AMOUNT OF MIXING WILL OCCUR AND WITH 850MB TEMPS AT 8C ON SUNDAY AND 12C ON MONDAY...HIGH TEMPERATURES WILL FLIRT WITH 70F ON SUNDAY TO MID TO UPPER 70S ON MONDAY. IF THE ATMOSPHERE IS SUPER ADIABATIC THEN TEMPERATURES MAY REACH 80F ON MONDAY. ON CAVEAT IS FOR THOSE ALONG THE SOUTH COASTLINE...SOUTHERLY WINDS WILL BRING THE COOL MARITIME AIR ONSHORE KEEP TEMPS IN THE 50S TO LOW 60S ON BOTH DAYS. BECAUSE OF THE MIXING...WINDS WILL BE GUSTY...NEAR 20-30 MPH. ONCE THE WINDS LIGHTEN UP DURING THE OVERNIGHT HOURS...COMBINED WITH THE SOUTHERLY WINDS...ANTICIPATE FOG DEVELOPMENT ESP ALONG THE SOUTH COAST. FINALLY THERE IS A LOW PROBABILITY THAT A FEW SHOWERS MAY DEVELOP ACROSS THE HIGH TERRAIN ON MONDAY DUE TO DIABATIC HEATING. AM NOT ANTICIPATING ANY STRONG OR SEVERE STORMS BUT PERHAPS A RUMBLE OF THUNDER OR TWO. BECAUSE OF THIS UNCERTAINTY LEFT IT OUT OF THE FORECAST FOR NOW BUT IT IS SOMETHING THE BEARS WATCHING. TUESDAY INTO WEDNESDAY.... GUIDANCE IS BEGINNING TO CLUSTER MORE TOGETHER ON THE TIMING AND INTENSITY OF THE APPROACHING COLD FRONTAL SYSTEM. THE LATEST 00Z MODELS INDICATE THAT A LOW PRESSURE SYSTEM WILL DEVELOP ALONG THE SLOW MOVING COLD FRONT BY TUESDAY NIGHT FOLLOWED BY STRONG HIGH PRESSURE BY WED NIGHT. ANTICIPATE A FEW SHOWERS TO DEVELOP AHEAD OF THE FRONT MONDAY NIGHT INTO TUESDAY. BUT AS SOON AS THE FRONT APPROACHES...EXPECT MODERATE TO POSSIBLY HEAVY PRECIP TO FALL. THIS PRECIP MAY CAUSE URBAN AND POOR DRAINAGE FLOODING...BUT MAY ALSO HELP ELEVATED THE RIVERS IF EVERYTHING LINES UP. HOWEVER WE WILL NEED TO MONITOR THIS POTENTIAL CLOSELY. BOTH AHEAD AND BEHIND THE FRONT...A VERY STRONG LLJ WILL DEVELOP WHICH WILL NOT ONLY AID IN THE MOISTURE TRANSPORT ALONG THE FRONT BUT WILL ALSO CREATE GUSTY WINDS THROUGH THE PERIOD. WIND GUSTS OF 20 TO 30 MPH ARE EXPECTED AHEAD OF THE FRONT BUT PERHAPS EVEN STRONGER GUSTS COULD OCCUR AS 925MB WINDS SPEEDS STRENGTHEN TO 60-80KTS. THIS WILL RESULT IN A POSSIBLE WIND ADV IF WE MIX ALL THE WAY TO 925MB. VERY STRONG CAA WILL OCCUR AS THE FRONT PASSES THROUGH BY WED. APPEARS THAT THE COLD AIR WILL RUSH INTO THE AREA WITH PRECIP LINGERING BEHIND THE SYSTEM. THIS WILL RESULT IN SOME P-TYPE ISSUES ESP ACROSS THE BERKSHIRES AND IN SOUTHERN NEW HAMPSHIRE. LASTLY WITH THE STRONG ONSHORE FLOW FROM THE SOUTH...WE WILL NEED TO WATCH FOR THE POTENTIAL FOR SOME MINOR SPLASHOVER ALONG THE SOUTH SHORE AND INTO NARRAGANSETT BAY. TIDES ARE SLOWLY INCREASING WITH HIGH ASTRONOMICAL TIDE PEAKING NEXT FRIDAY/SATURDAY. AS ONE CAN SEE THERE ARE A LOT OF HAZARDS THAT THIS STORM CAN POTENTIALLY DEVELOP. ALTHOUGH CONFIDENCE IS STILL A LITTLE UNCERTAIN...ESP SINCE THIS STORM IS STILL 5 DAYS AWAY...IT IS LOOKING LIKE A POTENT SPRING STORM WILL AFFECT THE EASTERN STATES NEXT WEEK. THURSDAY... STRONG HIGH PRESSURE WILL QUICKLY USHER INTO THE REGION BEHIND THE COLD FRONT. TEMPERATURES WILL DROP WELL BELOW AVERAGE WITH HIGH JUST REACHING 50F. && .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
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LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /THROUGH SATURDAY NIGHT/...HIGH CONFIDENCE. AREA OF RAIN SHOWERS ARRIVES IN WESTERN NEW ENGLAND 19-21Z AND REACHES COAST 21-23Z. MOST OF SHOWERS ARE LIGHT AND CIGS/VSBYS SHOULD REMAIN VFR. WEAK SEA BREEZE EXPECTED ALONG E MA COAST AROUND 20Z OR SO. IFR CIGS/VSBYS ARRIVE THIS EVENING NEAR S COAST DUE TO S FLOW AND MAY REACH UP E MA COAST INTO BOS LATER TONIGHT. ELSEWHERE AREAS MVFR CIGS/VSBYS IN SHOWERS/FOG. SHOULD SEE RAPID IMPROVEMENT TO VFR BY 12Z SAT...EXCEPT ON CAPE COD AND ISLANDS WHERE IT MAY TAKE UNTIL 16Z. WINDS DIMINISH SAT AFTERNOON AND SHOULD ALLOW FOR SEA BREEZES ALONG BOTH E AND S COASTS. POTENTIAL FOR MVFR/IFR CIGS TO RETURN LATE SAT NIGHT DUE TO MORE OF A S/SW FLOW...ESPECIALLY NEAR S COAST. KBOS TERMINAL...HIGH CONFIDENCE IN TAF. STILL FORECASTING WEAK SEA BREEZE AFTER 20Z BUT WINDS COULD REMAIN MORE S/SE. KBDL TERMINAL...HIGH CONFIDENCE IN TAF. OUTLOOK...SUNDAY THROUGH TUESDAY... SUNDAY...MODERATE CONFIDENCE. MAINLY VFR. LOCAL MVFR-IFR CIGS/VSBYS ALONG S COAST IN LOW OCEAN CLOUDS AND PATCHY FOG WHICH SHOULD IMPROVE BY MIDDAY. EXPECT S WINDS TO INCREASE DURING THE AFTERNOON...GUSTING TO AROUND 25 KTS. MAY SEE LOW CLOUDS/PATCHY FOG RETURN AFTER MIDNIGHT ALONG S COAST WITH MVFR-IFR CONDITIONS. MONDAY...MODERATE CONFIDENCE. LOCAL MVFR-IFR CIGS/VSBYS ALONG S COAST EARLY MON SHOULD IMPROVE...OTHERWISE VFR ON MONDAY. GUSTY S-SW WINDS IN PLACE...UP AROUND 30 KTS. TUESDAY...LOW CONFIDENCE. MAINLY VFR WITH SOME MVFR IN ISOLATED SHOWER DEVELOPMENT AHEAD OF APPROACHING COLD FRONT.
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&& .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /THROUGH FRIDAY NIGHT/...HIGH CONFIDENCE. SW WINDS GRADUALLY DIMINISH THIS AFTERNOON AS WEAK SEA BREEZE DEVELOPS ALONG E MA COAST BY MID AFTERNOON. SCA REMAINS POSTED FOR OUTER WATERS DUE TO LEFTOVER SEAS. TONIGHT... STALLED FRONT NEAR THE SOUTH COAST OF MASS AND RI. THE WIND FIELD NEAR THIS FRONT WILL BE LIGHT. SWELL WILL CONTINUE AROUND 5 FEET ON THE SOUTHERN OUTER WATERS AND PARTS OF THE RI WATERS. ALSO SOME POTENTIAL FOR LOW VSBYS IN FOG OVERNIGHT. SATURDAY...HIGH PRESSURE BUILDS IN WITH A LIGHT WIND FIELD. SWELL OF 5 FEET WILL STILL LINGER ON THE OUTER WATERS AND SOME OF THE RI WATERS. OUTLOOK...SATURDAY NIGHT THROUGH TUESDAY... SATURDAY NIGHT...HIGH CONFIDENCE. VSBY RESTRICTION LATE SAT NIGHT ON THE OUTER WATERS IN PATCHY FOG. SUNDAY...MODERATE CONFIDENCE. LIGHT/VRBL WINDS SHIFT TO SE-S DURING SUNDAY. WILL INCREASE... GUSTING TO AROUND 25 KT. EXPECT SEAS TO BUILD AS WELL. VSBY RESTRICTIONS IN PATCHY FOG. MONDAY-TUESDAY...MODERATE CONFIDENCE. EXPECT S-SW WINDS TO GUST UP TO 30 KT WITH SEAS INCREASING IN RESPONSE ESP ON THE SOUTHERN OUTER WATERS. VSBY RESTRICTIONS DURING THE OVERNIGHT AND EARLY MORNING HOURS IN PATCHY FOG...THEN SHOWERS MOVE IN ON TUE. && .HYDROLOGY...
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LATEST NERFC FORECASTS BRING LOWER CT RIVER FROM HARTFORD THROUGH MIDDLE HADDAM JUST INTO MINOR FLOOD BEGINNING SUN EVENING...BASED UPON WATER BEING ROUTED DOWNSTREAM. THOSE WITH INTERESTS ALONG LOWER REACHES OF CT RIVER SHOULD PAY ATTENTION TO THE LATEST FORECASTS.
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&& .BOX WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...NONE. NH...NONE. RI...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT SATURDAY FOR ANZ235-237- 254>256. SMALL CRAFT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR ANZ250. && $$ SYNOPSIS...WTB/DUNTEN NEAR TERM...JWD SHORT TERM...WTB LONG TERM...DUNTEN AVIATION...JWD MARINE...WTB/DUNTEN HYDROLOGY...JWD

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