Area Forecast Discussion
Issued by NWS Burlington, VT

Current Version | Previous Version | Text Only | 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
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KBTV 240303 AFDBTV AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BURLINGTON VT 1103 PM EDT THU APR 23 2015 .SYNOPSIS... A SLOW MOVING LOW PRESSURE SYSTEM IN THE UPPER LEVELS OF THE ATMOSPHERE WILL BE THE MAIN FEATURE ON THE WEATHER MAP. THE LOW WILL REMAIN IN THE AREA THROUGH THE WEEKEND, AND PRODUCE RAIN OR SNOW SHOWERS, PLENTY OF CLOUDS, AND BELOW NORMAL TEMPERATURES. THE BEST CHANCES FOR SNOW WILL BE ACROSS THE HIGHER TERRAIN AND DURING THE NIGHTTIME HOURS WITH COOLER TEMPERATURES. THE VALLEYS WILL SEE MAINLY RAIN SHOWERS. && .NEAR TERM /UNTIL 8 AM FRIDAY MORNING/...
-- Changed Discussion --
AS OF 1041 PM EDT THURSDAY...GOING FORECAST REMAINS IN GOOD SHAPE. WITH LATEST UPDATE...MADE SOME SMALL ADJUSTMENTS TO HOURLY PARAMETERS SUCH AS TEMPS AND POPS FOR NEXT SEVERAL HOURS...TO REFLECT LATEST OBSERVATIONAL DATA AND TRENDS. RADAR LOOP SHOWING A SCATTERING OF RAIN/SNOW SHOWERS ACROSS THE REGION AS WE REMAIN UNDER UPPER LEVEL LOW. SHOWER ACTIVITY BECOMING MORE PRONOUNCED ACROSS NORTHERN MOUNTAINS AT THIS TIME...ESPECIALLY THE NORTHERN GREENS. EXPECT THIS TREND TO CONTINUE AS UPPER LOW SLIDES TO OUR EAST AND FLOW TURNS MORE NORTHWESTERLY. CURRENT FORECAST HAS THIS WELL COVERED...ALONG WITH THE EXPECTATIONS OF SOME LIGHT SNOW ACCUMULATIONS OVER THE HIGHER TERRAIN. EARLIER DISCUSSION... VERTICALLY STACKED SURFACE AND 500 MB LOW OVER THE NORTHEAST WITH A RIDGE OVER THE WESTERN US, TYPICAL OF WHAT WE SAW ALL LAST WINTER. CENTER OF 500 MB LOW MOVES DIRECTLY OVERHEAD WEST TO EAST OVERNIGHT TONIGHT WITH A COUPLE OF VORT CENTERS ROTATING AROUND THE LOW THAT WILL CONTROL OUR WEATHER. FIRST VORT LOBE MOVED THROUGH THE FORECAST AREA TODAY WITH RAIN/SNOW SHOWERS THROUGH MIDDAY, AND A SECOND VORT WILL BRING NEW RAIN/SNOW CHANCES TO US OVERNIGHT. TEMPERATURES THROUGH THE LAYER ARE COOLING WITH COLD POOL ALOFT, AND DIURNAL TEMP DROP TONIGHT WILL LOWER SURFACE TEMPS TO SUPPORT SNOW DOWN TO 1000 FT ELEVATION OR SO. BETTER CHANCES IN THE USUAL WEST FACING UPSLOPE AREAS. ABOVE ONE FROUDE THIS AFTERNOON IN DESTABILIZED AIR BECOME LESS THAN ONE, INDICATING BLOCKED FLOW AND MOST PRECIP REMAINING IN WIND FACING SIDES. OVERNIGHT LOWS LOWER ELEVATIONS NEAR FREEZING AND IN THE UPPER 20S IN THE HIGHER TERRAIN. SNOW ACCUMULATIONS WILL VARY WITH ELEVATION AND TEMPERATURE, WITH WARM TEMPS AT LOW ELEVATIONS SUPPORTING ONLY A DUSTING ON GRASSY SURFACES AND COLDER HIGHER ELEVATIONS ACCUMULATING AN INCH OR TWO.
-- End Changed Discussion --
&& .SHORT TERM /8 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/... AS OF 352 PM EDT THURSDAY...BY 8AM FRIDAY CENTER OF THE 500 MB LOW WILL SHIFT EAST OF VERMONT TO MAINE...HOWEVER COLD POOL REMAINS. EXPECT SOME LINGERING TERRAIN INDUCED SNOW SHOWERS/RAIN SHOWERS IN THE HIGHER TERRAIN, THEN RENEWED INSTABILITY AND SCATTERED SHOWERS AGAIN IN THE AFTERNOON AS COLD POOL ALOFT...AROUND -30C AT 500 MB...REMAINS. FAVORED LOCATIONS AGAIN WILL BE MORE SO IN THE HIGHER TERRAIN AND LESS IN THE VALLEYS. BY SATURDAY UPPER LOW SHEARS OUT TO AN ELONGATED EAST/WEST ORIENTATION AS THE RIDGE IN THE WEST FLATTENS AND MAIN WESTERLIES TRACK SOUTH OF THE AREA THROUGH THE MID ATLANTIC STATES. STILL SOME WEAK INSTABILITY AND SHORTWAVE TROUGH FORCING SO LEFT A CHANCE FOR SHOWERS MAINLY IN THE NORTHERN HIGHER TERRAIN. HOWEVER SATURDAY IS THE BEST CHANCE FOR A DRY PERIOD THROUGH THIS SHORT TERM TIMEFRAME. TEMPS WILL SEE A GRADUAL WARMING TREND AS HEIGHTS RISE AND COLDEST PART OF THE COLD POOL ASSOCIATED WITH THE UPPER LOW SHIFTS EASTWARD. HOWEVER THEY WILL GENERALLY TREND BELOW NORMAL. PLENTY OF CLOUDS TO REMAIN WITH ONLY PATCHES OF SUNSHINE. && .LONG TERM /SUNDAY THROUGH THURSDAY/... AS OF 357 PM EDT THURSDAY... THE END OF THE WEEKEND WILL BE JUST THE SAME AS THE START... PERSISTENT NORTHWEST UPSLOPE FLOW WITH A CLOSED UPPER LEVEL LOW ROTATING AROUND ITSELF CENTERED OVER NEW ENGLAND. BOTH THE GFS/ECMWF START OUT IN A SIMILAR PATTERN WITH THE UPPER LEVEL LOW ALOFT OVER NEW ENGLAND AND A NORTHERN STREAM SURFACE LOW OVER NOVA SCOTIA WITH A SOUTHERN STREAM LOW DRIFTING OFFSHORE OFF THE VIRGINIA COAST. FROM THERE THE MODELS HAVE RELATIVELY WEAK RUN TO RUN CONSISTENCY WITH REGARDS TO TIMING AND INTENSITY. YESTERDAY THE 12Z GFS WAS PROGRESSIVE AND PUSHED A WEAK LOW OFFSHORE QUICKLY AND THE ECMWF WAS A BIT SLOWER DEVELOPING A PHASED LOW PRESSURE SYSTEM OFFSHORE EAST OF THE BENCHMARK. THE 00Z AND 12Z GFS TODAY HOWEVER SHOW A LESS PROGRESSIVE SYSTEM THAT DEVELOPS A 972MB COASTAL ABOUT 200 MILES EAST OF THE BENCHMARK AND THE ECMWF NO LONGER SHOWS THAT SOLUTION AND JUST FORECASTS A WEAK LOW MOVING OFFSHORE. EITHER WAY THE NET RESULT WILL BE WEST TO NORTHWEST UPSLOPE WINDS THAT WILL BRING AN OFF AND ON CHANCE FOR UPSLOPE RAIN/SNOW SHOWERS. EXPECT RAIN SHOWERS DURING THE DAY TIME WITH A MIX OF RAIN AND SNOW OVERNIGHT DURING WEEKEND AND EARLY INTO NEXT WEEK. I TENDED TO RELY A BIT MORE ON A BLEND OF OUR SUPERBLEND AND ECMWF TO AVOID THE STRONG COASTAL LOW FROM THE GFS FOR THE TIME BEING. THROUGH TUESDAY EXPECT THAT PATTERN TO REMAIN LOCKED IN BEFORE A WEAK SURFACE RIDGE BUILDS IN FINALLY PUSHING THE PERSISTENT UPPER LEVEL LOW INTO THE CANADIAN MARITIMES. AS THE RIDGE BUILDS DRIER AIR WILL FILTER INTO THE REGION AND THAT SHOULD BRING A TEMPORARY END TO THE SPORADIC UPSLOPE SNOW SHOWERS TUESDAY EVENING. REGARDING TEMPERATURES, THERE IS REALLY NO SIGNIFICANT CHANGE FROM THE PREVIOUS LINE OF THINKING. DAYTIME TEMPS WILL GRADUALLY WARM THROUGH THE EARLY PORTION OF THE WEEK SEEING TEMPS RETURN TO NEAR NORMAL WITH THE EARLY WEEK SEEING MAX TEMPS IN THE UPPER 40S TO MID 50S ON SUNDAY WARMING TO MID 50S TO LOW 60S BY WEDNESDAY NEXT WEEK. OVERNIGHT LOWS WILL BE PRETTY CONSISTENTLY IN THE UPPER 20S IN THE HIGHER TERRAIN ABOVE 2000 FEET TO THE MID TO UPPER 30S IN THE SAINT LAWRENCE AND CHAMPLAIN VALLEYS. && .AVIATION /03Z FRIDAY THROUGH TUESDAY/... THROUGH 00Z SATURDAY...A VARIETY OF FLIGHT CATEGORIES IS EXPECTED TONIGHT BEFORE GIVING WAY TO VFR CONDITIONS FOR LATER FRIDAY MORNING AND AFTERNOON. WEST/NORTHWESTERLY FLOW WILL INCREASE THIS EVENING AND TONIGHT LEADING TO TERRAIN-DRIVEN RAIN AND SNOW SHOWERS...ESPECIALLY SLK/MPV. NOT MUCH IMPACT EXPECTED AT BTV/PBG/MSS EXCEPT FOR A POSSIBLE LIGHT SHOWER...WITH VFR IN THE FORECAST. MPV/SLK WILL SEE PERIODS OF SNOW SHOWERS...WITH MVFR/IFR LIKELY. RUT EXPECTED TO SEE SOME LOWER CEILINGS (MVFR) AND A FEW SHOWERS NEARBY. LOWER CEILINGS/SHOWERS GRADUALLY DISSIPATE AND LIFT ON FRIDAY WITH ALL SITES VFR BY 16Z. SOME ADDITIONAL INSTABILITY-DRIVEN SCATTERED SHOWERS MAY DEVELOP IN THE AFTERNOON HOURS. SURFACE WINDS GENERALLY ANTICIPATED TO BE OUT OF THE WEST FROM 5-15 KNOTS...WITH SOME GUSTS UP TO 20 KNOTS...MAINLY ON FRIDAY. OUTLOOK 00Z SATURDAY THROUGH TUESDAY... FOR THE ENTIRE PERIOD - VFR WITH PERIODS OF MVFR (AND POSSIBLY BRIEF IFR) IN SCATTERED RAIN SHOWERS DURING THE DAY AND RAIN/SNOW SHOWERS AT NIGHT. && .HYDROLOGY...
-- Changed Discussion --
UPDATED 1102 PM THURSDAY...THE FLOOD WARNING CONTINUES FOR THE BARTON RIVER NEAR COVENTRY. THE RIVER WENT ABOVE FLOOD STAGE EARLY THIS MORNING AND WENT UP QUICKLY...CRESTING AROUND 8.8 FEET THIS AFTERNOON. SINCE THEN...THE WATER LEVEL OF THE RIVER HAS BEGUN TO FALL...AND AT 11 PM IT WAS AT 8.4 FEET. EXPECT THIS TREND TO CONTINUE OVERNIGHT. CURRENTLY THE BARTON RIVER NEAR COVENTRY IS THE ONLY RIVER THAT WE EXPECT TO REACH FLOOD STAGE AS MOST OF THE OTHER RIVERS AND STREAMS HAVE CRESTED BELOW FLOOD STAGE.
-- End Changed Discussion --
&& .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...HANSON NEAR TERM...RJS/HANSON SHORT TERM...HANSON LONG TERM...DEAL AVIATION...MUCCILLI HYDROLOGY...TEAM BTV

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