Area Forecast Discussion
Issued by NWS Burlington, VT

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
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 KBTV 292339 AFDBTV AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BURLINGTON VT 739 PM EDT FRI MAY 29 2015 .SYNOPSIS... SURFACE HIGH PRESSURE WILL BE OVER THE REGION THROUGH EARLY SATURDAY. A STRONG SURFACE COLD FRONT WILL APPROACH FROM THE NORTHWEST SATURDAY AFTERNOON AND CROSS THE AREA OVERNIGHT. THIS FRONT WILL STALL OUT SOUTH OF OUR FORECAST AREA AND BECOME A FOCUS FOR SEVERAL WAVES OF SHOWERS DURING THE FIRST PART OF THE WEEK. && .NEAR TERM /UNTIL 8 AM SATURDAY MORNING/... AS OF 739 PM EDT FRIDAY...FRIDAY AFTERNOON CLOSES WITH FILTERED SUNSHINE ACROSS THE NORTH COUNTRY, AS MID-LEVEL MOISTURE SPILLS IN ON THE WESTERN END OF A DEEP-LAYER ANTICYCLONE CENTERED OVER LONG ISLAND/SOUTHERN NEW ENGLAND. THOUGH LOOKING AT A GENERALLY QUIET EVENING ALL THINGS CONSIDERED, SURFACE ANALYSIS DEPICTS A SUBTLE SURFACE TROUGH FROM WESTERN PA CURRENTLY TRIGGERING SHOWERS AND THUNDERSTORMS IN THAT VICINITY. THAT TROUGH SEPARATES MORE COMFORTABLE DEWPOINTS IN THE 50S IN PLACE, TO A MORE MOIST/HUMID AIRMASS WITH MID-60S DEWPOINTS. THIS FEATURE WILL LIFT NORTHEAST TOWARDS OUR AREA AFTER MIDNIGHT. MOST HI-RES GUIDANCE INDICATE A GENERALLY DRY PASSAGE, BUT A FEW, SUCH AS THE BTV-4 WRF AND TO A LESSER EXTENT MOST RECENT HRRR OUTPUT, SHOW SOME LIGHT SHOWERS ACROSS ST. LAWRENCE VALLEY INTO THE ADIRONDACKS REGION AFTER MIDNIGHT. FOR NOW, I`VE KEPT SLIGHT CHANCE SHOWERS GOING IN THIS AREA AND WILL RE-EVAL WITH TRENDS IN RADAR AND LATER EVENING GUIDANCE. OTHERWISE, PRIMARY CHALLENGE WILL BE TIMING WHEN COOLING HALTS ACROSS THE NORTH COUNTRY, IN THE FACE OF WARM/MOIST ADVECTION AND INCREASING SOUTHWEST WINDS. THIS HAPPENS SOONER FURTHEST WEST (TOWARD MIDNIGHT) WITH LONGER IN EASTERN VERMONT. LOWS TONIGHT TO RANGE IN THE UPPER 50S IN EASTERN VERMONT, BUT WILL BE SOME 10 DEGREES WARMER IN THE CHAMPLAIN AND ST. LAWRENCE VALLEYS. && .SHORT TERM /8 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/... AS OF 415 PM EDT FRIDAY...COLD FRONT APPROACHES FROM THE NORTHWEST SATURDAY AND SHOWERS AND THUNDERSTORMS DEVELOP OUT AHEAD OF THIS FEATURE ON SATURDAY AFTERNOON. BEST CHANCE FOR THUNDERSTORMS APPEARS TO BE AFTER 18Z...AND MAINLY NORTHERN NEW YORK AND THE CHAMPLAIN VALLEY. OUR REGION CONTINUES TO BE UNDER A MARGINAL RISK OUT OF SPC. BETTER DYNAMICS AND STRONGER SHEAR WILL BE WELL NORTH OF THE AREA...CLOSER TO STRONG SHORT WAVE TROF MOVING ACROSS ONTARIO AND QUEBEC. DAYTIME MAX TEMPS WILL REACH THE MID 70S TO MID 80S. CAPE VALUES REACH OVER 2000 IN THE SAINT LAWRENCE VALLEY. OVERNIGHT AS THE FRONT CONTINUES ACROSS OUR FORECAST AREA AND WITH LOSS OF DAYTIME HEATING EXPECT CONVECTION TO END AND JUST SOME SHOWERS CONTINUING. COLD FRONT WILL STALL OUT TO OUR SOUTH AND BECOME THE FOCUS FOR SEVERAL ROUNDS OF PRECIPITATION. SUNDAY NIGHT WILL SEE SHOWERS MOVE ACROSS NEW YORK AND SOUTHERN NEW ENGLAND...HAVE SOME LIKELY POPS MENTIONED IN OUR SOUTHERN ZONES. TEMPERATURES WILL BE MUCH COOLER ON SUNDAY AS REGION IS IN THE COOL SECTOR BEHIND COLD FRONT...MAX TEMPS WILL ONLY BE IN THE UPPER 50S AND LOWER 60S...A GOOD 20 DEGREES COOLER THAN SATURDAY. SUNDAY NIGHT TEMPERATURES WILL DROP INTO THE 40S. && .LONG TERM /MONDAY THROUGH FRIDAY/... AS OF 400 PM EDT FRIDAY...RATHER TRANQUIL EXTENDED FORECAST PERIOD FORESEEN BASED ON CONSENSUS OF 00Z GFS/GFS ENSEMBLE MEAN AND 00Z ECMWF. DEEP-LAYER NWLY FLOW ON ERN PERIPHERY OF SFC ANTICYCLONE BUILDING EWD FROM THE GREAT LAKES REGION WILL PROVIDE DRIER CONDITIONS AND MORE SEASONABLE TEMPERATURES TO START THE PERIOD WEDNESDAY NIGHT. ANTICIPATE MOSTLY CLEAR SKIES...AND IF SURFACE WINDS DROP OFF SUFFICIENTLY...SHOULD SEE OVERNIGHT LOWS RANGING FROM NEAR FREEZING IN THE NORTHERN ADIRONDACKS AND FAR NORTHEASTERNVT...TO AROUND 40F IN THE CHAMPLAIN VALLEY REGION. AFOREMENTIONED SURFACE HIGH BUILDS SLOWLY EWD ACROSS THE NORTHEASTERN CONUS PROVIDING PLEASANT/MOSTLY CLEAR CONDITIONS THURSDAY THROUGH AT LEAST THE FIRST HALF OF FRIDAY. HIGHS WILL BE IN THE MID 60S THURSDAY...BEFORE MODERATING BACK INTO THE LOW 70S ON FRIDAY. SOME DIFFERENCES BETWEEN 00Z GFS AND 00Z ECMWF CONCERNING POTENTIAL SHORTWAVE TROUGH MOVING EWD FROM THE GREAT LAKES FRIDAY NIGHT INTO SATURDAY. THE GFS IS MORE ROBUST WITH THIS FEATURE...AND TRACKS STRONGEST UVV ACROSS OUR SRN ZONES LATE FRIDAY NIGHT INTO SATURDAY. THE 00Z ECMWF - ON THE OTHER HAND - KEEPS BEST PRECIPITATION CHANCES TO OUR SOUTH. THE OFFICIAL FORECAST INDICATES SOME INCREASING CLOUDS LATER FRIDAY...FOLLOWED BY 15-30 POPS FOR SHOWER ACTIVITY FRIDAY NIGHT THRU SATURDAY...WITH HIGHEST POP VALUES ACROSS SRN ZONES. CLOUDS COULD KEEP TEMPS IN THE UPR 60S TO AROUND 70F FOR SATURDAY...BEFORE TRENDING WARMING (LOW-MID 70S) WITH BETTER POTENTIAL FOR SUNSHINE ON SUNDAY. && .AVIATION /00Z SATURDAY THROUGH WEDNESDAY/... THROUGH 00Z SUNDAY...VFR (POSSIBLE MVFR MIST AT MPV) WITH INCREASING SOUTH WINDS THROUGH OVERNIGHT. PRIMARY AVIATION FOCUS WILL BE IN THE LATTER HALF OF THE TAF PERIOD, DUE TO GUSTY SOUTH WINDS AND POTENTIAL FOR SHOWERS AND THUNDERSTORMS INTO SATURDAY AFTERNOON/EVENING. MOSTLY CLEAR WITH SCT-BKN CIRRUS CLOUDS INTO THE OVERNIGHT TONIGHT. I`VE CONTINUED MENTION OF 4SM BR AT MPV AFTER 08Z, THOUGH ENOUGH LOW-LEVEL FLOW MAY PRECLUDE MUCH IF ANY MIST FROM DEVELOPING. INITIALLY LIGHT/VARIABLE WINDS BUT BECOME SOUTH 7-10 KTS. CONTINUED MID- TO HIGH CLOUDS INTO SATURDAY. STRENGTHENING GRADIENT AHEAD OF SURFACE COLD FRONT SHOULD ALSO ALLOW FOR SOUTHERLY WINDS TO FURTHER INCREASE INTO THE 10-15 KT RANGE WITH GUSTS 25-28 KTS. SHOWER/THUNDERSTORM COVERAGE LIKELY TO BE MORE SCATTERED, BUT THREAT SOME COULD TURN STRONG WITH GUSTY OUTFLOW WINDS, LIGHTNING AND REDUCED VISIBILITY IN HEAVY DOWNPOURS. BEST SHOT AT SEEING THIS ACTIVITY AFTER 18Z WOULD BE AT MSS AND SLK, BUT I`VE ALSO SHOWN VCSH AT BTV AND PBG. MPV AND SLK NOT LIKELY TO SEE THIS ACTIVITY UNTIL AFTER 00Z. OUTLOOK 00Z SUNDAY THROUGH WEDNESDAY...A SURFACE COLD FRONT APPROACHING FROM SOUTHEASTERN ONTARIO WILL BRING SCATTERED SHOWERS AND THUNDERSTORMS ON SATURDAY AFTERNOON INTO SATURDAY NIGHT. SOME STORMS COULD BE STRONG WITH LOCALIZED GUSTY AND ERRATIC OUTFLOW WINDS...HEAVY RAINFALL...AND FREQUENT LIGHTNING...MAINLY MID AFTERNOON THROUGH EARLY EVENING HOURS SATURDAY. BRIEF IFR CONDITIONS CAN BE EXPECTED WITH ANY THUNDERSTORM ACTIVITY. MODERATELY STRONG GRADIENT WINDS (SOUTH TO SOUTHWEST AT 15-25 KTS) WILL CONTINUE THROUGH THE EARLY EVENING PERIOD. PERIODS OF RAIN CONTINUE DURING SATURDAY NIGHT WITH DEVELOPING N-NW WINDS BEHIND THE SURFACE COLD FRONT. TRENDING VFR ACROSS NORTHERN AREAS DURING THE DAYLIGHT HOURS SUNDAY...BUT STALLING FRONTAL ZONE MAY RESULT IN POSSIBLE MVFR SHOWERS AT TIMES SUNDAY NIGHT INTO MONDAY...MAINLY FOR RUT/MPV. AVIATION WX CONDITION PREDICTABILITY LOW AT THIS POINT FROM MONDAY NIGHT THRU WEDNESDAY. && .MARINE... AS OF 400 PM EDT FRIDAY...A COLD FRONT WILL MOVE ACROSS THE AREA SATURDAY AFTERNOON AND OVERNIGHT. SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED. A LAKE THUNDERSTORM ADVISORY MAY BE NEEDED FOR LAKE CHAMPLAIN SATURDAY AFTERNOON AND SATURDAY NIGHT. SOUTH WINDS WILL INCREASE TO 15 TO 25 KNOTS ON SATURDAY. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...NEILES NEAR TERM...NEILES/LOCONTO SHORT TERM...NEILES LONG TERM...BANACOS AVIATION...BANACOS/LOCONTO MARINE...NEILES

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