Area Forecast Discussion
Issued by NWS Burlington, VT-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
FXUS61 KBTV 220226
Area Forecast Discussion
National Weather Service Burlington VT
1026 PM EDT Tue Mar 21 2017
An arctic cold front will push across the region tonight with
scattered snow showers, though only minor accumulations are
expected. Cold and blustery weather returns for Wednesday before
temperatures begin to moderate from Thursday onward into next
.NEAR TERM /THROUGH WEDNESDAY NIGHT/...
-- Changed Discussion --As of 1026 PM EDT Tuesday...Late evening and overnight forecast
remains in good shape. Arctic cold front remains northwest of
the region at this time, and shower activity along the boundary
has become more spotty over the past few hours as it swung into
the Ottawa valley. Locally run 4km WRF is handling it very well,
and shows the activity redeveloping as the front enters into the
BTV CWA with some orographic enhancement along the western
slopes of the Adirondacks and northern Green Mountains. Previous
forecast has this covered well so really no changes needed
there, but did adjust temps again slightly based on cooler
observations from the Champlain Valley eastward. Have a good
Previous Discussion...Well advertised arctic cold front to
sweep through the area tonight with a brief period of scattered
to perhaps numerous snow showers occurring along the boundary,
especially across northern counties. BTV SNSQ perhaps still
showing best threat of heavier shsn or squalls to occur in these
areas as well, especially along the intl border where mesoscale
output suggests formation of a small mesolow traversing west to
east from near CYOW to CYSC in the 01-08Z time frame. Indeed a
quick look at latest satellite imagery shows potential
initiation of this feature immediately north of Georgian Bay as
of 19Z. Thus prior forecasts of solid chance to likely pops
(40-70%) across the north, and slight to low chance pops south
still looks right on track. Given quick moving nature of this
system only minor snowfall is expected with a dusting to perhaps
an inch in the northern valleys and up to 2 inches in higher
terrain. Negligible amounts expected south. Temperatures a bit
tricky, holding relatively mild in the 30s before readings fall
sharply into the teens/single digits late as front clears well
east and south. This could create some areas of black ice where
moisture lingers on area roads.
Any lingering snow showers/flurries Wednesday morning to end by
afternoon as strong arctic high pressure builds into the region.
Skies should trend partly to mostly sunny in all areas by mid to
late afternoon under persistent and gusty northwesterly flow into
the 20 to 30 mph range. This will keep quite the chill in the air as
daytime temperatures hold nearly steady in the 12 to 22 range.
Blustery flow then gradually abates by Wednesday night as core of
surface high nears. Generally clear skies are expected with chilly
overnight lows in the positive/negative single digits...perhaps a
spot reading near 10 above in warmest valley locales.
-- End Changed Discussion --
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
As of 325 PM EDT Tuesday....Ridge of surface high pressure
crests over the region Thursday, shifting south and east into
the Atlantic late Thursday and Thursday night. This will bring
return SW flow which warmer air will filter into the North
Country. 500mb heights will increase Thursday night, but clouds
will increase as vorticity embedded in the midlevel flow will
extend into the North Country late Thursday night into Friday
Temperatures will reach the 20s to low 30s in Thursday, cooling
about 10 degrees in the early part of Thursday night before
warm air advection in SW flow begins a non-diurnal trend.
.LONG TERM /FRIDAY THROUGH TUESDAY/...
As of 325 PM EDT Tuesday...More active pattern in the long term
as Friday will see the aforementioned mid level weak shortwave
or vorticity bring chance of snow Friday morning. Warming
throughout the day will transition snow into rain for most
areas. Behind this shortwave, colder air filters in as winds
shift NW Friday night. Surface high pressure will build in over
James bay and extend southward into the North Country. This will
provide a break in precip as warm front associated with low
pressure system over midwest, remains south of the forecast area
over the weekend. The surface ridge will shift north and east
Sunday night with the low over the midwest traversing NW and
bringing another chance for precipitation to the beginning of
the work week. This system may bring a period of wintry mix but
uncertainty remains due to differences in thermal profiles.
.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
Through 00Z Thursday...A strong arctic cold front will move into
the region overnight, mainly after 04Z Wednesday. Expecting
some areas of IFR/MVFR in snow showers or local snow squalls,
mainly after 04Z through 14Z Wedensday. Northwest surface wind
gusts will increase to 20 to 30 knots after 06Z and continue
through 00Z Thursday. Expecting conditions to become VFR across
Vermont and northern New York by 18Z Wednesday.
00Z Thursday through Sunday...
00Z Thursday through 12Z Friday - VFR/high pressure.
12Z Friday through Sunday - VFR/MVFR/IFR in scattered rain/snow