FXUS61 KBTV 051136
AFDBTV
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BURLINGTON VT
636 AM EST SAT DEC 5 2009
.SYNOPSIS...
LOW PRESSURE WILL MOVE ALONG THE MID ATLANTIC COAST AND OUT OVER THE
ATLANTIC OCEAN TODAY. THIS SYSTEM WILL SPREAD LIGHT SNOW ACROSS
PORTIONS OF THE NORTH COUNTRY THIS AFTERNOON...MAINLY SOUTH AND EAST
OF BURLINGTON. SOUTH AND EAST VERMONT WILL RECEIVE AN INCH OR TWO OF
SNOW WHILE LESSER AMOUNTS ARE EXPECTED ELSEWHERE. SNOW SHOWERS WILL
LINGER IN NORTHERN AREAS SUNDAY...BUT MORE WIDESPREAD SNOW IS
EXPECTED MONDAY AS A CLIPPER-TYPE SYSTEM SKIRTS ACROSS THE
NORTHEASTERN U.S.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 354 AM EST SATURDAY...CURRENT SURFACE ANALYSIS INDICATES
LOW PRESSURE OFF THE CAROLINA COAST. THIS FEATURE WILL STRENGTHEN
AND QUICKLY TREK NORTHEAST TODAY AND TONIGHT. ALL MODELS SHOW
THIS SYSTEM WILL REMAIN WELL SOUTH OF THE BENCHMARK WHICH IS
REINFORCED BY CURRENT 3HR MSL PRESSURE CHANGE ANALYSIS. THIS WILL
KEEP THE HIGHEST QPF IN SOUTHERN NEW ENGLAND WITH LIMITED IMPACTS
TO THE NORTH COUNTRY. HOWEVER...IT IS EXPECTED THAT SOME LIGHT
SNOW WILL MAKE IT FAR ENOUGH NORTH TO FALL ACROSS PORTIONS OF THE
FORECAST AREA...ESPECIALLY SOUTH AND EAST OF BURLINGTON. ALTHOUGH
GREATEST FGEN WILL REMAIN IN SOUTHERN NEW ENGLAND...GFS DOES SHOW
A SECONDARY AREA OF 850 MB FGEN TO AFFECT SOUTHEAST VERMONT THIS
EVENING...AND EXPECT THE MAJORITY OF THE PRECIPITATION AND
MEASURABLE SNOWFALL TO BE LATE THIS AFTERNOON INTO EARLY TONIGHT.
WHILE THE HIGHER ELEVATIONS WILL BEGIN TO SEE ACCUMULATIONS BY
MID AFTERNOON...THE CHAMPLAIN VALLEY WILL BE HARD PRESSED TO SEE
ANY MEASURABLE SNOW AS TEMPERATURES WILL BE IN THE MID TO UPPER
30S. ALL TOLD...SNOWFALL AMOUNTS WILL RANGE FROM A HALF AN INCH
IN THE NORTH CENTRAL GREENS AND HIGHER PEAKS OF THE ADIRONDACKS
TO AROUND 2.5 INCHES NEAR SPRINGFIELD...WITH A TENTH OF AN INCH
OR LESS EXPECTED NORTH AND WEST OF BURLINGTON. TEMPERATURES WILL
GENERALLY BE IN THE 30S AS 850MB TEMPS LOOK TO BE -8C TO -10C.
SNOW WILL GRADUALLY SHIFT EAST TONIGHT AS THE LOW PULLS AWAY FROM
COASTAL NEW ENGLAND AND WILL COME TO AN END ACROSS MUCH OF THE
FORECAST AREA BY MIDNIGHT. LIGHT SNOW SHOWERS WILL LINGER IN
EASTERN VERMONT THROUGH THE OVERNIGHT HOURS. LOWS WILL BE NEAR
SEASONAL NORMALS...GENERALLY THE UPPER TEENS TO MID 20S.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
AS OF 354 AM EST SATURDAY...LIGHT SNOW SHOWERS WILL CONTINUE
ACROSS THE NORTHERN HALF OF THE FORECAST AREA SUNDAY AS A VORT
MAX ROTATES AROUND THE UPPER LOW AS IT SKIRTS BY TO THE NORTH.
NAM/WRF MODELS ALSO INDICATE LAKE EFFECT SNOW OFF OF LAKE ONTARIO
FALL ACROSS PORTIONS OF THE ADIRONDACKS. ANY ACCUMULATION WITH
THESE SHOWERS SHOULD BE MINIMAL. BETTER CHANCES FOR ACCUMULATING
SNOW ARRIVE BY MONDAY AS A CLIPPER SYSTEM QUICKLY MOVES ACROSS
THE SOUTHERN GREAT LAKES AND INTO NEW ENGLAND IN ZONAL FLOW
ALOFT. TEMPS SHOULD REMAIN COLD ENOUGH FOR ALL SNOW MONDAY WITH
HIGHS IN THE LOWER TO MID 30S EXPECTED.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 354 AM EST SATURDAY...MAIN FOCUS FOR THE EXTENDED FORECAST
PERIOD IS POTENTIAL STORM SYSTEM AND HEAVY QPF EVENT FOR
WEDNESDAY AND WEDNESDAY NIGHT.
AT THE START OF THE PERIOD...LOW AMPLITUDE 700MB TROUGH SHOULD BE
EXITING THE REGION TO THE EAST DURING MONDAY NIGHT...WITH A 30
PERCENT CHANCE OF SNOW SHOWERS LINGERING...ESPECIALLY ACROSS THE
HIGHER TERRAIN. BEST CHANCE SHOULD BE BEFORE MIDNIGHT...WITH SOME
LESSENING OF CLOUD COVER TOWARD DAYBREAK AS MID-LEVEL HEIGHTS
RISE. LOW TEMPS SHOULD GENERALLY BE IN THE TEENS TO LOWER
20S...DEPENDING ON THE DEGREE OF BINOVC DURING THE LATTER HALF OF
THE NIGHT.
TUESDAY AND TUESDAY NIGHT SHOULD BE FAIR WITH A SFC RIDGE AND
MOBILE 700MB SHORTWAVE RIDGE CRESTING ACROSS THE NERN U.S..
TEMPERATURES SHOULD BE SEASONABLE TUESDAY AFTN WITH MOSTLY SUNNY
CONDITIONS AND HIGHS IN THE LOW TO MID 30S IN THE VALLEYS. CLOUDS
BEGIN TO INCREASE FROM SW-NE TUESDAY NIGHT WITH PRIMARY LOW
TRACKING NEWD FROM THE OHIO VALLEY AND ONSET OF WAA/ISENTROPIC
ASCENT ACROSS THE NORTH COUNTRY. WITH SFC RIDGE SLIDING EWD INTO
THE CANADIAN MARITIMES...OVERALL PATTERN FAVORS AN INLAND TRACK
OF PRIMARY SFC LOW...THOUGH SOME REDEVELOPMENT TOWARD THE NEW
ENGLAND COAST IS EXPECTED DURING THE DAY WEDNESDAY PER GFS/ECMWF.
IT/S STILL EARLY TO DETERMINE P-TYPE...SO HAVE USED GFS ENSEMBLE
AS A GUIDE WITH POTENTIAL FOR 850MB WARMING ABOVE 0C ACROSS THE
REGION AS PRIMARY 850MB LOW TRACKS TO THE WEST/NW. THUS...HAVE
GONE ABOVE MEX-MOS HIGH TEMPS FOR WEDNESDAY AND MAINTAIN A
RAIN/SNOW MIX FOR NOW...PENDING EVENTUAL TRACK AND COASTAL
REDEVELOPMENT POTENTIAL. CERTAINLY...QPF LOOKS SIGNIFICANT...WITH
BOTH THE OPERATIONAL 00Z GFS/ECMWF SHOWING 1 TO 1.5 INCHES QPF
FOR THE 24-HR PERIOD ENDING 12Z THURSDAY. THE OTHER ISSUE IS THE
PROSPECT FOR STRONG SELY WIND GUSTS OF 30-45 MPH...ESPECIALLY
ACROSS THE HIGHER TERRAIN AND ALONG THE WEST SLOPES OF THE GREEN
MTNS. WE WILL CONTINUE TO MONITOR THIS POTENTIAL.
AS LOW DEPARTS TO THE NORTH/NORTHEAST DURING THE DAY
THURSDAY...FLOW PATTERN BECOMES NWLY ACROSS THE NORTH COUNTRY AND
FAVORABLE FOR OROGRAPHIC SNOW SHOWER ACTIVITY...AIDED BY LOW-
LEVEL CAA AND STEEP LAPSE RATES. HAVE SHOWN 20-40 POPS FOR -SW
THU/THU NIGHT...HIGHEST ACROSS THE MTNS WITH FAVORABLE FLOW
REGIME IN PLACE. WITH 850MB TEMPERATURES TRENDING COLDER /-12 TO
-14C AT 00Z FRIDAY PER GFS/...HIGHS WILL GENERALLY BE IN THE LOW
30S IN THE VALLEYS AND 20S IN THE 1-2 KFT ELEVATIONAL BAND
THU/FRI. GUSTY NWLY WINDS ARE POSSIBLE...ESPECIALLY THURSDAY WITH
STRONG GRADIENT FLOW IN PLACE.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
THROUGH 12Z SUNDAY...A RATHER UNIFORM 10 KFT OVERCAST PREVAILS
ACROSS THE NORTH COUNTRY AS OF 11Z...EXCEPT OVC 5-6 KFT ACROSS
THE ST. LAWRENCE VALLEY/KMSS ASSOCIATED WITH CLOUDS WITH ORIGINS
ACROSS THE ERN GREAT LAKES. A STORM SYSTEM ORGANIZING OFF THE
CAROLINA COAST WILL CONTINUE TO SPREAD MID LEVEL CLOUDS NORTHWARD
ACROSS THE REGION THIS MORNING/EARLY AFTN...WITH CEILINGS
REMAINING IN THE VFR CATEGORY. GREATEST IMPACT FROM THIS SURFACE
LOW WILL REMAIN SOUTH AND EAST OF THE NORTH COUNTRY...BUT
INCREASED LIFT WILL GENERATE LOWER CLOUDS 4-5 KFT AGL THIS AFTN
AND EVENING. SFC LOW PRESSURE PASSES WELL SOUTHEAST OF NEW ENGLAND
LATE THIS AFTN AND EVENING. IT APPEARS THE NWRN EDGE OF ANY LIGHT
SNOW ACTIVITY WILL REACH RUT/MPV...WITH A PERIOD OF MVFR
CONDITIONS POSSIBLE BETWEEN ROUGHLY 21-03Z. ELSEWHERE AT THE TAF
SITES...ANTICIPATE OVERCAST CONDITIONS BUT NO PCPN EXPECTED. WINDS
WILL GENERALLY BE LIGHT FROM THE NORTH TO NORTHWEST DURING THE
DAYLIGHT HRS SATURDAY...AND THEN REMAIN SO THRU 12Z SUN. SOME
PARTIAL CLEARING IS POSSIBLE AFTER 05Z SUNDAY AS SURFACE LOW MOVES
WELL EAST OF THE AREA.
OUTLOOK 12Z SUNDAY THROUGH WEDNESDAY...A WEAK CLIPPER SYSTEM WILL
BRING A CHANCE FOR LIGHT SNOW AND GENERALLY MVFR CONDITIONS TO
THE NORTH COUNTRY MONDAY AFTN/EVE. A MORE SIGNIFICANT STORM SYSTEM
IS POSSIBLE WITH MIXED PCPN DEVELOPING DURING THE DAY WEDNESDAY
WITH LOCALLY STRONG WINDS AND MVFR/IFR CONDITIONS. OTHERWISE...MAINLY
VFR CONDITIONS ARE EXPECTED FOR SUN/SUN NIGHT...AND FOR TUE/TUE
NIGHT.
&&
.CLIMATE...
MORE INTERESTING SNOWFALL DATA FOR BURLINGTON...COUNTING TODAY
DECEMBER 4TH OUR LAST MEASURABLE SNOWFALL OCCURRED ON APRIL
8TH...WHICH IS 240 DAYS AGO. THIS RANKS 3RD LONGEST STREAK WITHOUT
MEASURABLE SNOWFALL AT BTV...BEHIND 247 DAYS IN 1948 AND 248 DAYS IN
1945. THE TOP 2 SHOULD REMAIN IN TACT...WITH SOME LIGHT SNOW
ACCUMULATION POSSIBLE BY NEXT WEEK.
BTV REMAINS WITHOUT MEASURABLE SNOWFALL SO FAR THIS SEASON. THE
RECORD LATEST DATE IS WITHIN SIGHT.
FOR BURLINGTON...ON AVERAGE THE FIRST MEASURABLE SNOW HAPPENS
NOVEMBER 6TH. HERE ARE THE 10 LATEST FIRST SNOWS FOR BURLINGTON
GOING BACK TO 1906...ALONG WITH THE SEASONAL TOTAL SNOW THAT
FOLLOWED.
SEASON TOTAL
RANK DATE SNOWFALL (INCHES)
1. 12/7/1937 45.1
2. 12/5/1915 54.4
3. 12/?/2009 ????
4. 12/1/1948 40.7
5. 11/30/1918 69.6
11/30/1953 83.6
11/30/1960 51.6
8. 11/28/1913 56.5
9. 11/27/1941 57.7
10. 11/26/1982 80.5
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MB
NEAR TERM...MB
SHORT TERM...MB
LONG TERM...BANACOS
AVIATION...BANACOS
CLIMATE...
