Area Forecast Discussion
Issued by NWS Boston, MA

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KBOX 280148 AFDBOX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TAUNTON MA 948 PM EDT MON JUL 27 2015 .SYNOPSIS... A FAST MOVING DISTURBANCE WILL BRING A ROUND OF SCATTERED SHOWERS AND THUNDERSTORMS TO EASTERN NEW ENGLAND TUESDAY AFTERNOON AND EVENING. HOT AND HUMID TUESDAY THROUGH THURSDAY. A COLD FRONT MAY BRING SCATTERED THUNDERSTORMS LATE THURSDAY AND THURSDAY NIGHT. WARM AND DRY WEATHER IS EXPECTED FRIDAY INTO NEXT WEEKEND. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
-- Changed Discussion --
10 PM UPDATE... RADAR HAS QUIETED DOWN OVER THE PAST FEW HOURS THEREFOR HAVE LOWERED POPS FOR THE FIRST HALF OF THE NIGHT. WATER VAPOR IMAGERY SHOWING A SHORTWAVE MOVING DOWN FROM THE QUEBEC/ONTARIO LINE. BELIEVE THIS SHORTWAVE WILL TRIGGER A SHOWER OR TWO OVER THE AREA WITH NORTHERN NEW ENGLAND HAVING THE BEST CHANCE OF SEE MORE COVERAGE. STILL PLENTY OF INSTABILITY ACROSS THE AREA WHICH COULD ALLOW A RUMBLE OF THUNDER WITHIN ANY SHOWERS. SKIES ARE STARTING TO CLEAR OUT ACROSS THE CT VALLEY. SINCE THAT REGION SAW A GOOD 1-3 INCHES OF PRECIP ANTICIPATE IT TO FOG IN OVERNIGHT DO TO INVERSION. WILL CONTINUE TO WAIT AND SEE WHEN THE FOG DEVELOPS TO DEBATE ON HOISTING A DENSE FOG ADV. PREVIOUS DISCUSSION... IT LOOKS LIKE MUCH OF THE OVERNIGHT HOURS WILL BE DRY. WE WILL HAVE TO WATCH FOR THE RISK FOR A FEW SPOT SHOWERS/ISOLATED THUNDERSTORMS DEVELOPING ACROSS EASTERN NEW ENGLAND OVERNIGHT WITH SOME ELEVATED INSTABILITY. LOW LEVEL FORCING DOES NOT SEEM AS STRONG AS LAST NIGHT THOUGH DESPITE FAIRLY HIGH MUCAPES. THEREFORE...JUST WENT WITH LOW POPS OVERNIGHT AS MUCH OF THE REGION SHOULD END UP DRY. THE OTHER CONCERN WILL BE FOR AREAS OF FOG TO DEVELOP OVERNIGHT. WITH RATHER LIGHT WINDS AND WET GROUND...WILL HAVE TO WATCH FOR SOME PATCHY DENSE FOG ESPECIALLY ACROSS THE INTERIOR. THAT WILL DEPEND UPON THE AMOUNT OF BREAKS IN THE SKY COVER OVERNIGHT...BUT SOMETHING LATER SHIFTS WILL HAVE TO WATCH CLOSELY. LOW TEMPS WILL GENERALLY BOTTOM OUT BETWEEN 65 AND 70.
-- End Changed Discussion --
&& .SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/... ***A FEW STRONG TO SEVERE THUNDERSTORMS POSSIBLE TUESDAY AFTERNOON AND EARLY EVENING ALONG WITH LOCALLY HEAVY RAINFALL ACROSS EASTERN MA AND RHODE ISLAND*** TUESDAY... ANY LOW CLOUDS AND FOG PATCHES SHOULD BURN OFF BY LATE MORNING ACROSS THE REGION. OTHERWISE...EXPECT PARTLY SUNNY SKIES TO RESULT IN A VERY WARM TO EVEN BORDERLINE HOT AFTERNOON. HIGH TEMPS WILL TOP OUT MAINLY IN THE UPPER 80S TO NEAR 90. IN ADDITION...IT WILL BE RATHER HUMID OUTSIDE WITH DEWPOINTS IN THE 60S AND RATHER LIGHT WINDS. MAINLY DRY WEATHER EXPECTED TUESDAY MORNING...BUT WE CAN NOT RULE OUT A SPOT SHOWER OR THUNDERSTORM. THE MAIN CONCERN THEN TURNS TO A STRONG PIECE OF SHORTWAVE ENERGY THAT WILL BE DROPPING SOUTH ACROSS THE EASTERN NEW ENGLAND COAST. GIVEN VERY WARM AND HUMID AIRMASS WITH 500 MB TEMPS AROUND -10C...WE SHOULD BE ABLE TO GENERATE MLCAPE VALUES ON THE ORDER OF 1500 J/KG. THE SHORTWAVE COMBINED WITH THE INSTABILITY SHOULD LEAD TO SCATTERED CONVECTION. WHILE AN ISOLATED SHOWER OR THUNDERSTORM IS POSSIBLE ACROSS THE INTERIOR...GREATEST CONCERN IS ACROSS EASTERN MA AND RHODE ISLAND AS THEY WILL BE CLOSER TO THE SHORTWAVE...BUT CAN NOT COMPLETELY RULE OUT CENTRAL MA. WILL RUN WITH SCATTERED SHOWERS/THUNDERSTORMS MAINLY ACROSS THE EASTERN HALF OF THE REGION TUESDAY AFTERNOON AND EARLY EVENING WITH SOME ENHANCED WORDING. AS FOR SEVERE WEATHER POTENTIAL...LOW LEVEL WIND FIELDS ARE RATHER WEAK WHICH WILL BE A LIMITING FACTOR. NONETHELESS...STRONG WINDS ALOFT WILL LIKELY GENERATE 0 TO 6 KM SHEAR VALUES OF 35 TO 45 KNOTS AND THERE IS AN INVERTED V LOOK TO THE SOUNDINGS. THIS MEANS THAT THERE IS THE RISK FOR A FEW STRONG TO SEVERE THUNDERSTORMS...MAINLY ACROSS EASTERN MA AND RHODE ISLAND...BUT CAN NOT RULE OUT CENTRAL MA. LOCALLY DAMAGING WIND GUSTS AND HAIL ARE THE CONCERNS FOR TUESDAY AFTERNOON AND EARLY EVENING. HIGHEST RISK MIGHT BE ALONG THE SEA BREEZE FRONT THAT SETS UP ACROSS EASTERN MA AND RHODE ISLAND AS IT WILL PROVIDE A FOCUS FOR CONVECTION. ALSO...SOMETIMES WE END UP WITH SOME TRAINING ON THESE BOUNDARIES AND THE RISK FOR VERY LOCALIZED FLOODING. && .LONG TERM /TUESDAY NIGHT THROUGH MONDAY/... HIGHLIGHTS... * TRIPLE-H WEATHER WED/THU WITH HIGHS IN 90S. * SCATTERED STORMS THU/THU NIGHT. * DRIER BUT STILL VERY WARM FRI THRU SUN. OVERALL...GOOD AGREEMENT AMONGST THE MODELS ON THE SYNOPTIC PATTERN. UPPER RIDGE OVER THE GREAT LAKES AND OHIO VALLEY SLOWLY WEAKENS AS ITS PUSHED EASTWARD BY AN UPPER LOW TRAVELING ACROSS THE CANADIAN PRAIRIE. THIS LOW WILL BECOME STATIONARY OVER HUDSON BAY AND REMAIN THERE THROUGH MUCH OF THE FORECAST PERIOD WITH THE SURFACE REFLECTION PARKED JUST BELOW IN ABOUT THE SAME LOCATION. THIS WILL KEEP SOUTHERN NEW ENGLAND IN SOUTHWESTERLY TO WESTERLY SURFACE WINDS BRINGING HOT AND HUMID AIR INTO THE REGION. TUESDAY NIGHT...COULD SEE SOME LINGERING SHOWERS AND THUNDERSTORMS INTO THE EARLY PART OF THE NIGHT AS A FRONT EXTENDING FROM LOW PRESSURE IN THE MARITIMES MOVES OFFSHORE. OTHERWISE...A FAIRLY HUMID NIGHT WITH WARM TEMPERATURES EXPECTED TO REMAIN IN THE UPPER 60S TO LOWER 70S. WEDNESDAY...ANOTHER HOT...HUMID...AND HAZY DAY EXPECTED AS THE UPPER LEVEL RIDGE MOVES OVER SOUTHERN NEW ENGLAND. HIGH TEMPERATURES ARE EXPECTED TO BE IN THE LOWER 90S FOR MOST LOCATIONS. WITH DEWPOINTS REMAINING IN THE UPPER 60S TO LOWER 70S...HEAT INDICES WILL EASILY BE IN THE UPPER 90S TO NEAR 100. MAIN QUESTION FOR WEDNESDAY WILL BE WHETHER OR NOT THEY COULD REACH 100 AND HEAT ADVISORIES BE NEEDED. THURSDAY...A WEAK FRONT EXTENDING FROM THE LOW PRESSURE IN HUDSON BAY WILL SWING THROUGH SOUTHERN NEW ENGLAND ALLOWING FOR A POTENTIAL OF SHOWERS AND THUNDERSTORMS LATE IN THE DAY INTO THURSDAY NIGHT. DECENT INSTABILITY...0-6KM SHEAR...AND MARGINAL MID LEVEL LAPSE RATES WILL ALLOW A FEW OF THESE STORMS TO BECOME STRONG. FRIDAY THROUGH SUNDAY...WITH THE SYNOPTIC SCALE PATTERN FAIRLY STATIONARY...EXPECT HOT AND SOMEWHAT HUMID WEATHER TO CONTINUE THROUGH THE WEEKEND. TEMPERATURES WILL BE IN THE UPPER 80S TO LOWER 90S. MONDAY...ANOTHER FRONTAL SYSTEM MAY BRING SHOWERS AND THUNDERSTORMS TO THE REGION. && .AVIATION /02Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /THROUGH TUESDAY AFTERNOON/... TONIGHT...LOW TO MODERATE CONFIDENCE. DRY WEATHER PROBABLY DOMINATES MOST LOCATIONS OVERNIGHT...A FEW SPOT SHOWERS OR PERHAPS A THUNDERSTORM OR TWO CAN NOT BE RULED OUT. OTHERWISE...MAIN CONCERN OVERNIGHT WILL BE FORMATION OF LOW CLOUDS AND FOG. TIMING UNCERTAIN...BUT WILL HAVE TO WATCH FOR LOCALLY DENSE FOG DEVELOPING OVERNIGHT ESPECIALLY ACROSS THE INTERIOR. TUESDAY...MODERATE TO HIGH CONFIDENCE. ANY LOW CLOUDS AND FOG PATCHES SHOULD IMPROVE TO VFR BY LATE MORNING. MAIN CONCERN IS SCATTERED SHOWERS/THUNDERSTORMS THAT ARE EXPECTED TO DEVELOP GENERALLY ACROSS EASTERN MA/RHODE ISLAND. WHILE ACTIVITY WILL BE HIT AND MISS...THE POTENTIAL IS THERE FOR ISOLATED STRONG TO SEVERE STORMS WITH LOCALLY HEAVY RAINFALL. KBOS TERMINAL...HIGH CONFIDENCE IN TAF. KBDL TERMINAL...MODERATE CONFIDENCE IN TAF. LOW CLOUDS AND SOME FOG MAY DEVELOP LATE TONIGHT. OUTLOOK /TUESDAY NIGHT THROUGH SATURDAY/... TUESDAY NIGHT...LOW CONFIDENCE. MAINLY VFR. LOW PROBABILITY OF MVFR/IFR CONDITIONS IN SCT -SHRA/TSRA ACROSS THE EASTERN HALF OF THE AREA DURING THE EARLY PART OF THE NIGHT. WEDNESDAY...HIGH CONFIDENCE. VFR. THURSDAY...MODERATE CONFIDENCE. MAINLY VFR EXCEPT IN SCT -SHRA/TSRA. FRIDAY THROUGH SATURDAY...MODERATE CONFIDENCE. VFR.
-- End Changed Discussion --
&& .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /THROUGH TUESDAY AFTERNOON/...HIGH CONFIDENCE. WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS THROUGH TUESDAY AFTERNOON. A FEW SPOT SHOWERS AND PERHAPS A THUNDERSTORM WILL BE POSSIBLE TONIGHT. HOWEVER...A BETTER CHANCE OF A FEW STRONG TO SEVERE THUNDERSTORMS TUESDAY AFTERNOON WHICH MAY RESULT IN BRIEFLY STRONG WIND GUSTS AND HAIL. SPECIAL MARINE WARNINGS MAY BE NEEDED WITH THE HIGHEST RISK ACROSS OUR WATERS ADJACENT TO EASTERN MA. OUTLOOK /TUESDAY NIGHT THROUGH SATURDAY/... HIGH CONFIDENCE. QUIET BOATING WEATHER IS EXPECTED THROUGH THE PERIOD. THERE MAY BE SHOWERS AND THUNDERSTORMS OVER THE WATERS TUESDAY NIGHT AND AGAIN THURSDAY AND THURSDAY NIGHT. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...NONE. RI...NONE. MARINE...NONE. && $$ SYNOPSIS...FRANK/RLG NEAR TERM...FRANK/DUNTEN SHORT TERM...FRANK LONG TERM...RLG AVIATION...FRANK/RLG MARINE...FRANK/RLG

USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.