Area Forecast Discussion
Issued by NWS Burlington, VT

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000 FXUS61 KBTV 030745 AFDBTV AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BURLINGTON VT 345 AM EDT MON AUG 3 2015 .SYNOPSIS... A COLD FRONT WILL MOVE INTO THE AREA LATER TODAY INTO TONIGHT WITH SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS, A FEW OF WHICH COULD BE SEVERE. BEHIND THIS FRONT SEASONABLY COOLER AIR WILL ARRIVE FOR TUESDAY INTO WEDNESDAY, THOUGH WITH A CONTINUED CHANCE OF SHOWERS AND A FEW THUNDERSTORMS. DRIER WEATHER RETURNS FROM THURSDAY ONWARD INTO MUCH OF THE UPCOMING WEEKEND AS TEMPERATURES REMAIN SLIGHTLY BELOW EARLY AUGUST NORMS. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 318 AM EDT MONDAY...POTENTIALLY ACTIVE WEATHER IS EXPECTED FOR TODAY AS THE LARGE-SCALE UPPER TROUGH ACROSS CENTRAL CANADA MAKES FURTHER INROADS INTO THE REGION. THIS WILL TAKE THE SHAPE OF A COLD FRONT AND ASSOCIATED 925-850 MB PRE-FRONTAL TROUGH WHICH WILL SWING INTO THE REGION THIS AFTERNOON AND THIS EVENING. WILL CONTINUE THE IDEA OF A FEW OF THE STORMS TRENDING STRONG TO LOCALLY SEVERE FROM MID- AFTERNOON ONWARD INTO EARLY EVENING PER LATEST SPC SWODY1, BUT AS TYPICAL WITH SEVERE WEATHER EPISODES IN OUR REGION IT`S NEVER CLEAR CUT. WORKING IN FAVOR OF MORE ROBUST ACTIVITY WILL BE UPPER DYNAMICAL JET SUPPORT, DECENT LAPSE RATES IN THE MID-LEVELS AND MORE THAN ENOUGH LOW TO MID LEVEL BULK SHEAR. WITH DEWPOINTS RANGING ONLY IN THE UPPER 50S TO LOWER 60S HOWEVER, MODIFIED SOUNDINGS SUGGEST SB CAPE VALUES LIKELY TO RANGE ONLY IN THE 500-1000 J/KG RANGE, PERHAPS SLIGHTLY HIGHER. IN ADDITION UNIDIRECTIONAL TROPOSPHERIC FLOW WILL BE NEARLY PARALLEL TO THE SLOWLY ADVANCING FRONTAL ZONE TO OUR WEST, THUS PVA VALUES WON`T BE THAT GREAT. FINALLY, WE`LL BE DEALING WITH AT LEAST SOME HIGHER LEVEL DEBRIS CLOUDINESS FROM THIS MORNING`S DEEP CONVECTION ACROSS THE GREAT LAKES. WITH ALL OF THAT SAID WE`RE STILL EXPECTING A GENERAL REDEVELOPMENT OF SHOWERS/STORMS THIS AFTERNOON ACROSS NORTHERN NEW YORK WHICH WILL PROGRESS SLOWLY EASTWARD INTO WESTERN VERMONT BY LATE AFTERNOON AND EASTERN VERMONT BY THE EVENING HOURS AS SUGGESTED BY VARIOUS CAM OUTPUT. GIVEN UNIDIRECTIONAL FLOW FIELDS, LINEAR BOWING SEGMENTS SHOULD BE THE PRIMARY CONVECTIVE MODE WITH A FEW DAMAGING WIND GUSTS AND REPORTS OF LARGE HAIL POSSIBLE IN THE 2-10 PM TIME FRAME. HIGHS TODAY WILL REMAIN WARM (80S), ESPECIALLY EAST WHERE A FEW SPOTS MAY NEAR 90F ALONG THE LOWER CT RIVER VALLEY WHERE A GREATER DEGREE OF SUNSHINE SHOULD OCCUR. && .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/... AS OF 318 AM EDT MONDAY...EVENING CONVECTION THEN WANES ACROSS OUR EASTERN COUNTIES INTO NH/MA WITH ANY SEVERE THREAT ENDING BEFORE MIDNIGHT. STILL COULD SEE A FEW TAIL-END SHOWERS AS THE ACTUAL FRONTAL BOUNDARY PUSHES INTO THE REGION OVERNIGHT BUT ACTIVITY SHOULD TREND WIDELY SCATTERED AT BEST. LOWS GENERALLY RANGING FROM 55 TO 65 OR VERY CLOSE TO SEASONAL NORMS. BY TUESDAY INTO WEDNESDAY UPPER TROUGH PROGRESSES BODILY EASTWARD AND SAGS SOUTHWARD SLIGHTLY OVER TIME. LATEST MODELS CONTINUE PRIOR TRENDS IN SHOWING ADDITIONAL SHORTWAVE ENERGY PROGRESSING ACROSS THE REGION IN THE DEEP CYCLONIC FLOW ALOFT WITH FAVORABLE ARRIVAL TIMES (FOR SHOWERS/ISOLD THUNDER) DURING THE AFTERNOON HOURS. SCATTERED COVERAGE IS EXPECTED, FOCUSED ACROSS OUR CENTRAL AND NORTHERN COUNTIES WITH NO SEVERE WEATHER EXPECTED. HIGHS SHOULD TREND GRADUALLY COOLER OVER TIME WITH NEAR SEASONAL READINGS IN THE 70S TO AROUND 80 EXPECTED ON TUESDAY, THEN IN THE UPPER 60S TO MID 70S ON WEDNESDAY. OVERNIGHT LOWS GENERALLY IN THE 50S, LOCALLY NEAR 60 ALONG LAKE CHAMPLAIN WHERE WATER TEMPERATURES ARE CURRENTLY IN THE LOWER TO MID 70S. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... AS OF 342 AM EDT MONDAY...CYCLONIC FLOW WILL PREVAIL IN THE MEAN FOR THE EXTENDED. THOUGH GENERALLY UNSETTLED, IT`S A MAINLY UNEVENTFUL PERIOD. 1000-500 MB THICKNESS TROUGHING ASSOCIATED WITH THE MEAN TROUGH WILL ALLOW FOR SEVERAL PERIODS OF DIURNAL SHOWERS THROUGH FRIDAY. HOWEVER, NOT LIKELY TO BE A WASHOUT ON ANY PARTICULAR DAY GIVEN AN ABSENCE OF STRONGER SHORTWAVE ENERGY AND SHALLOW MOISTURE DEPTH (PW VALUES UNDER AN INCH). WORTH NOTING THAT RECENT ECMWF SOLUTIONS CONTINUE TO TRY TO BRING NORTH A RATHER STRONG FRONTAL SYSTEM FROM THE MID-ATLANTIC TOWARD OUR SOUTHERN AREAS ON FRIDAY. I`M LARGELY DOWNPLAYING THIS IDEA AS ITS PARENT SHORTWAVE TROUGH LOOKS TO BE SPAWNED FROM CONVECTION OVER THE PLAINS DAYS EARLIER. THERMAL PROFILES ARE QUITE COOL AS 850 MB TEMPS ARE ONLY PROGGED TO BE IN THE +5 TO +8C RANGE, WHICH UNDER PARTIAL SUNSHINE WOULD SUPPORT LOW 70S FOR HIGHS AND LOWS IN THE 40S TO MID 50S. THOSE ARE BELOW EARLY-AUGUST NORMALS BY A FEW DEGREES, THOUGH QUITE COMFORTABLE. THOUGH SATURDAY LOOKS TO BE DRY, A WARM FRONT MOVES IN FROM THE WEST SATURDAY NIGHT/SUNDAY WITH POPS INCREASING TO CHANCE CATEGORY FOR SHOWERS/STORMS. HIGHS WELL INTO THE 70S/NEAR 80 AND LOWS IN THE 50S TO NEAR 60. && .AVIATION /08Z MONDAY THROUGH FRIDAY/... PLEASE SEE EQUIPMENT SECTION BELOW FOR KRUT DATA OUTAGE INFORMATION... THROUGH 06Z TUESDAY...ASIDE FROM VFR/MVFR RAIN FROM WEAKENING GREAT LAKES MCS AFFECTING MSS THROUGH 12Z, VFR ELSEWHERE. GREATER POTENTIAL IMPACTS TO AVIATION MONDAY WITH PROSPECTS FOR STRONG TO LOCALLY SEVERE THUNDERSTORMS. MCS CONTINUES TO WEAKEN WITH LEADING EDGE OF SHOWERS NEARING EASTERN SHORE OF LAKE ONTARIO WILL MOVE NORTHEASTWARD TOWARD MSS SHORTLY. I CAN`T RULE OUT ISOLATED LIGHTNING AND WILL AMEND IF A MORE IMMINENT THREAT BUT FOR NOW I`VE TREATED AS 6SM RA. LOOKS TO BE THE ONLY SITE WITH CHANCES FOR RAIN. LOW-LEVEL SOUTHELRY WIND FIELDS WILL STRENGTHEN SUPPORTING POTENTIAL LLWS AT MSS AND SLK. ASIDE FROM THAT, VFR SCT HIGH CLOUDS ELSEWHERE WITH SOUTH WINDS INCREASING UP TO 10-12 KTS. POTENTIAL FOR STRONG TO LOCALLY SEVERE THUNDERSTORMS MONDAY AFTERNOON ACROSS MOST OF THE TERMINALS AS COLD FRONT APPROACHES FROM GREAT LAKES. PRESENT INDICATIONS ARE THAT THE PRIMARY RISK AREA WOULD BE FROM SLK AND POINTS EAST. I`VE SHOWN 6SM +SHRA IN TAFS, TIMING 18-20Z THRU 01Z PER LATEST HI- RESOLUTION GUIDANCE. STRONG THUNDERSTORMS CAPABLE OF BRIEF IFR/LIFR VISIBILITY IN HEAVY DOWNPOURS, TURBULENCE AND LIGHTNING. WINDS WILL GUST TO 25 KTS DURING THE DAY BUT TEND TO STAY SUSTAINED AT 10-12 KTS TOWARD EVENING. OUTLOOK 06Z TUESDAY THROUGH FRIDAY... 06Z TUESDAY - 12Z TUESDAY...SCATTERED SHOWERS AND THUNDERSTORMS EXPECTED WITH COLD FRONTAL PASSAGE. BRIEF MVFR CIGS AND IFR VISIBILITIES POSSIBLE BENEATH HEAVIER CONVECTIVE CORES. GUSTY WINDS/TURBULENCE ALSO POSSIBLE. 12Z TUESDAY - 12Z THURSDAY...MAINLY VFR...SCT AFTERNOON SHOWERS/THUNDERSTORMS WITH BRIEF MVFR/IFR POSSIBLE. PATCHY IFR IN BR/FG POSSIBLE 06-12Z EACH MORNING, MAINLY AT KMPV/KSLK TERMINALS. 12Z THURSDAY ONWARD...MAINLY VFR AS SURFACE HIGH PRESSURE TRIES TO BUILD IN OVER THE GREAT LAKES REGION. && .MARINE... AS OF 342 AM EDT MONDAY...THE LAKE WIND ADVISORY CONTINUES. SOUTH WINDS HAVE STARTED TO INCREASE TO 15 TO 25 KNOTS AT COLCHESTER REEF AND DIAMOND ISLAND EARLY THIS MORNING. WINDS WILL CONTINUE AT/ABOVE LAKE WIND ADVISORY CRITERIA INTO THE AFTERNOON, THOUGH SHOULD BE ON THE HIGHER END OF THAT RANGE DURING THE MORNING HOURS. WAVES WILL BE AROUND 2-3 FT HIGHEST IN BROAD-LAKE AREAS EXPOSED TO THE SOUTH. IN ADDITION...STRONG TO POSSIBLY SEVERE THUNDERSTORMS ARE FORECAST MONDAY AFTERNOON AND EVENING. THESE STORMS WILL BE CAPABLE OF PRODUCING HEAVY RAIN WITH SIGNIFICANTLY REDUCED VISIBILITIES, GUSTY WINDS, FREQUENT LIGHTNING AND HAIL. PLEASE REMAIN WEATHER AWARE IF PLANNING TO BE OUT ON THE LAKE MONDAY. && .EQUIPMENT... AWOS OBSERVATIONAL DATA FROM THE RUTLAND/SOUTHERN VERMONT REGIONAL AIRPORT (KRUT) REMAIN UNAVAILABLE AT THIS TIME. FOR AVIATION PARTNERS CURRENT OBSERVATIONS MAY BE ACCESSED VIA TELCO. PLEASE REFERENCE FAA KRUT NOTAM 07/007 FOR MORE INFORMATION. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...JMG NEAR TERM...JMG SHORT TERM...JMG LONG TERM...LOCONTO AVIATION...LOCONTO MARINE...LOCONTO/MUCCILLI EQUIPMENT...JMG

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