National Weather Service National Headquarters

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KBTV 131213
AFDBTV

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BURLINGTON VT
713 AM EST FRI DEC 13 2013

.SYNOPSIS...
A COLD FRONT WILL CROSS THE AREA THIS MORNING...ACCOMPANIED BY SNOW
SHOWERS AND A FEW SQUALLS. IT WILL BE FOLLOWED BY CLEARING SKIES
AND FALLING TEMPERATURES THIS AFTERNOON. HIGH PRESSURE WILL BRING
CLEAR SKIES AND VERY COLD TEMPERATURES TO THE REGION TONIGHT. A
LOW PRESSURE SYSTEM WILL MOVE FROM THE MID ATLANTIC STATES LATER
SATURDAY UP TO NEAR CAPE COD BY SUNDAY MORNING...BRINGING A
SIGNIFICANT SNOWFALL TO THE NORTH COUNTRY.

&&

.NEAR TERM /UNTIL 7 PM THIS EVENING/...
-- Changed Discussion --
AS OF 653 AM EST FRIDAY...COLD FRONT EXTENDING FROM NEAR NEWPORT
VT TO SARANAC LAKE NY WILL CONTINUE TO MAKE ITS WAY SOUTH ACROSS
FORECAST AREA THIS MORNING. FRONT WILL CONTINUE TO MAKE ITS WAY
SOUTH ACROSS FORECAST AREA THIS MORNING. IT IS BEING PRECEDED BY
SOME SNOW SHOWERS...SOME OF WHICH HAVE BEEN LOCALLY HEAVY.
UNTIL FROPA HOWEVER...THE THREAT FOR SOME LOCALLY HEAVY SNOW
SHOWERS OR A BRIEF SQUALL WILL CONTINUE. ADDITIONAL ACCUMULATIONS
EARLY TODAY WILL BE GENERALLY A DUSTING TO 2 INCHES...JUST ENOUGH
TO CREATE SOME TRAVEL ISSUES. AFTER FROPA...THE CHANCES FOR SNOW
SHOWERS WILL DIMINISH. DRIER AND COLDER AIR ADVECTS INTO THE
REGION THIS AFTERNOON AS HIGH PRESSURE BEGINS TO RIDGE SOUTH INTO
THE AREA. LOOK FOR SKIES TO BECOME PARTLY SUNNY AND FOR ANY
LINGERING SNOW SHOWERS TO COME TO AN END. 850 MB TEMPS WILL FALL
FROM AROUND -18C THIS MORNING TO -22C BY DAYS END. EXPECT HIGHS
THIS MORNING TO RANGE FROM THE MID TEENS NORTH TO LOW 20S
SOUTH...WITH FALLING TEMPS THEREAFTER. WIND CHILL VALUES WILL
APPROACH -20 OVER THE ADIRONDACKS BY AFTERNOON...THUS WIND CHILL
ADVISORY FOR THIS REGION CONTINUED.
-- End Changed Discussion --

&&

.SHORT TERM /7 PM THIS EVENING THROUGH SUNDAY/...
AS OF 504 AM EST FRIDAY...WIDESPREAD SIGNIFICANT SNOW EXPECTED
SATURDAY NIGHT INTO SUNDAY.

SURFACE RIDGE BUILDS INTO THE NORTH COUNTRY TONIGHT...RESULTING
IN MAINLY CLEAR SKIES AND DIMINISHING WINDS ALONG WITH VERY COLD
TEMPERATURES. MUCH OF THE FORECAST AREA WILL SEE LOWS BELOW ZERO
SATURDAY MORNING...WITH THE NORMALLY COLDER PORTIONS OF THE
ADIRONDACKS AND NORTHEAST KINGDOM BOTTOMING OUT AROUND 20 BELOW.
THE WARM SPOTS WILL BE IN VICINITY LAKE CHAMPLAIN WHERE IT WILL BE
IN THE SINGLE DIGITS ABOVE ZERO.

COLD AIR REMAINS ENTRENCHED OVER THE NORTHEAST ON SATURDAY AS THE
SURFACE HIGH MAKES ITS WAY EAST INTO MAINE AND THE MARITIMES. EXPECT
HIGHS ONLY IN THE UPPER SINGLE NUMBERS AND LOWER TEENS.

MEANWHILE...LOW PRESSURE WILL BE DEVELOPING IN THE OHIO VALLEY
DURING THE DAY ON SATURDAY. EXPECT INCREASING CLOUDS IN ADVANCE OF
THIS SYSTEM WITH SOME SNOW DEVELOPING FROM SOUTHWEST TO NORTHEAST
DURING THE AFTERNOON. LOW PRESSURE WILL BE LOCATED IN SOUTHERN OHIO
SATURDAY EVENING WITH SECONDARY DEVELOPMENT OCCURRING NEAR VIRGINIA
COAST. THIS SECONDARY DEVELOPMENT IS IN RESPONSE TO SHORTWAVE
ENERGY APPROACHING FROM MISSISSIPPI VALLEY. THE COASTAL LOW WILL
THEN BECOME THE PRIMARY SYSTEM...AND DEEPEN WHILE TRACKING UP ALONG
THE EAST COAST SATURDAY NIGHT. THE LOW WILL PASS INSIDE THE
BENCHMARK OF 40N 70W LATE SATURDAY NIGHT/EARLY SUNDAY...AND IS
EXPECTED TO BE IN VICINITY OF CAPE COD 12Z SUNDAY. THE LOW WILL
THEN HEAD INTO THE GULF OF MAINE SUNDAY AFTERNOON. BEST FORCING AND
LIFT WITH THIS SYSTEM OCCURS SATURDAY NIGHT INTO EARLY SUNDAY WHEN
BULK OF SNOWFALL EXPECTED. UPPER LOW TRACK NOT AS FAVORABLE FOR A
MAJOR STORM...WITH CENTER WELL NORTH OF GREAT LAKES SATURDAY
NIGHT. SHORTWAVE IN ADVANCE OF THE UPPER LOW MOVES ACROSS
FORECAST AREA SATURDAY NIGHT/EARLY SUNDAY HOWEVER. MODELS IN GOOD
AGREEMENT ON ALL OF THE SYNOPTIC FEATURES...REGARDING TRACK AND
STRENGTH OF LOW AND UPPER LEVEL FEATURES. THERE IS ALSO GOOD AGREEMENT
ON QPF AMOUNTS...WHICH ARE EXPECTED TO AVERAGE AROUND A HALF INCH
ACROSS THE REGION. SOME HIGHER AMOUNTS LIKELY IN AREAS FAVORING
UPSLOPE ON EASTERLY FLOW...AND SOME LIGHTER TOTALS WHERE
DOWNSLOPING OCCURS. AMOUNTS OF .4 TO .6 INCHES OF LIQUID WITH
EXPECTED SNOW RATIOS AVERAGING AROUND 15:1 WOULD YIELD 6 TO 10
INCHES OF SNOW ACROSS FORECAST AREA...THUS A WINTER STORM WATCH
HAS BEEN ISSUED. SNOW WILL BEGIN TO TAPER OFF SUNDAY AFTERNOON.
HIGHS ON SUNDAY IN THE MID TEENS TO LOWER 20S.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 336 AM EST FRIDAY...COASTAL LOW CONTINUES TO PULL NORTHEAST
INTO THE GULF OF ST. LAWRENCE SUNDAY NIGHT WHILE THE PARENT
500/700MB CIRCULATIONS LAG BEHIND AND PASS TO OUR NORTH INTO
MONDAY MORNING. MOISTURE IS FAIRLY LIMITED BY THIS TIME...BUT
SHOULD BE ENOUGH TO PRODUCE SOME SNOW SHOWERS WITH GREATER
EMPHASIS ON THE HIGH TERRAIN AS EARLY NAM/GFS FROUDE NUMBERS SHOW
SLIGHTLY BLOCKED FLOW. BY MONDAY AFTERNOON THOUGH HIGH PRESSURE
BOTH AT THE SURFACE AND ALOFT BUILD INTO THE REGION SO ANY
LINGERING SNOW SHOWERS SHOULD END. MONDAY WILL BE THE COLDEST DAY
OF THE UPCOMING WEEK AS WELL WITH HIGHS STRUGGLING TO GET OUT OF
THE SINGLE DIGITS ACROSS NORTHERN NEW YORK...AND MID TEENS ACROSS
VERMONT.

HIGH PRESSURE IS SHORT LIVED AS OUR NEXT SYSTEM APPROACHES LATE
MONDAY NIGHT AS A WEAK CLIPPER WITH ADDITIONAL MOISTURE/DYNAMICS
PROVIDED TUESDAY/WEDNESDAY AS A BROAD UPPER TROUGH SETTLES OVER THE
NORTHEAST CONUS. COULD BE LOOKING AT A LONG DURATION ON/OFF LIGHT
SNOW EVENT THROUGH WEDNESDAY NIGHT WITH SOME MINOR IMPACTS AND
MODEST SNOW ACCUMULATIONS. HIGH PRESSURE RETURNS AGAIN FOR THE END
OF THE WORK WEEK WITH DRIER CONDITIONS. TEMPS TUESDAY THROUGH
THURSDAY MODERATE BACK TOWARDS NORMAL THOUGH STILL SLIGHTLY BELOW
WITH HIGHS IN THE 20S AND LOWS IN THE TEENS TO SINGLE DIGITS.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
THROUGH 12Z SATURDAY...GENERALLY VFR CONDITIONS ARE EXPECTED
THROUGH THE PERIOD WITH THE EXCEPTIONS AT KSLK/KMPV WHERE
LINGERING IFR SNOW CONTINUES THROUGH 14Z AS AN ARCTIC FRONT SAGS
SOUTHEASTWARD THROUGH THE REGION. WINDS WILL BE AN ISSUE TODAY
WITH WEST/NORTHWEST FLOW BEHIND THE FRONT PROVIDING GUSTS IN THE
20-25KT RANGE THROUGH THE DAY. AS HIGH PRESSURE BUILDS IN LATE IN
THE DAY AND INTO THE OVERNIGHT THOUGH...WINDS WILL DIMINISH. LOW
LEVEL MOISTURE REMAINS ABUNDANT OVERNIGHT THOUGH AND WHEN
COMBINED WITH EVEN LIGHT NORTHWEST FLOW...WE`LL LIKELY SEE
CONTINUED SCT-BKN SKIES ACROSS THE HIGHER TERRAIN TERMINALS SUCH
AS KSLK/AND KMPV...AN ALSO AT KBTV WITH SOME LAKE CLOUDS DRIFTING
AROUND IN THE VICINITY.

OUTLOOK 12Z SATURDAY THROUGH TUESDAY...

12Z SATURDAY THROUGH 21Z SATURDAY...GENERALLY VFR UNDER HIGH PRESSURE.

21Z SATURDAY THROUGH 00Z MONDAY...IFR/MVFR CONDITIONS DEVELOPING
IN LIGHT SNOW ASSOCIATED WITH COASTAL SYSTEM. HEAVIEST SNOWS LIKELY
06Z SATURDAY THROUGH 18Z SUNDAY.

00Z MONDAY THROUGH 06Z TUESDAY...MVFR CONDITIONS IMPROVING TO VFR
AS HIGH PRESSURE BUILDS INTO THE REGION.

06Z TUESDAY THROUGH 00Z WEDNESDAY...VFR TRENDING TO MVFR IN LIGHT
SNOW AS A WEAK CLIPPER SYSTEM TRACKS THROUGH THE REGION.

&&

.BTV WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
VT...WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY
     EVENING FOR VTZ001>012-016>019.
NY...WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY
     EVENING FOR NYZ026>031-034-035-087.
     WIND CHILL ADVISORY UNTIL 7 PM EST THIS EVENING FOR NYZ029>031-
     034.
-- End Changed Discussion --

&&

$$
SYNOPSIS...RJS
NEAR TERM...RJS
SHORT TERM...RJS
LONG TERM...LAHIFF
AVIATION...LAHIFF