Area Forecast Discussion
Issued by NWS Burlington, VT
FXUS61 KBTV 172353
Area Forecast Discussion
National Weather Service Burlington VT
653 PM EST Tue Jan 17 2017
A weak area of low pressure will move northeast up the Saint
Lawrence valley overnight. A secondary low pressure area will
form south of Long Island late tonight and will move slowly
eastward south of New England on Wednesday. A mix of snow,
sleet, freezing rain and rain will be over the North Country
overnight through Wednesday. A ridge of high pressure will
slowly build into the north country on Thursday and will remain
over the region through this weekend.
.NEAR TERM /THROUGH WEDNESDAY NIGHT/...
As of 645 PM EST Tuesday...No significant changes to the
forecast needed at this point. Precipitation is gradually
overspreading nrn NY and VT at 2330z, with mainly sleet
occurring across nrn NY, and snow across VT (in Rutland and
Addison Counties thus far). Did see a brief period of rain at
KRUT, but temperatures quickly cooled to 32F as low-levels
moistened and the switch to snow was quick as expected. The
same process should take place in the immediate BTV area next
hour or so as precipitation develops. It appears best forcing
and moisture is going to affect s-central VT, and the ern slopes
of the Greens Mtns, in particular, due to sely winds 25-30kts
in the 925-850mb layer (upslope flow). Already seeing 1/2SM
moderate snow at KVSF, and suspect highest accumulations by
morning will be along the ern slopes of the Greens Mtns from
Ludlow to Brookfield.
Total snowfall amounts will range from 3-6" along the ern slopes
of the Greens, to 2-4" across wrn VT and far nrn sections of
the state. With the mix of sleet and ZR at times, anticipate
1-3" snow/sleet generally across nrn NY. Slick travel is
expected overnight with snow covered roads possible, so allow
extra time if traveling.
Expecting precipitation to wind down Wednesday morning, with
some light rain or snow possible Wednesday afternoon. Have
lowered pops to slight chance for Wednesday night for some light
rain or snow showers possible.
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
As of 316 PM EST Tuesday...Generally improving conditions as
500mb shortwave exits east and ridge begins to build in over the
North Country. Lingering light showers focused over the high
terrain will diminish Thursday and Thursday night. Cooler air
will accompany high pressure with 925mb temperatures remaining
in the negative single digits to single digits above 0C. As the
500mb ridge crests over the region, gradually clearing skies
will result in min temperatures in the 20s to low 30s throughout
the period. Max temperatures will generally range from the mid
30s to low 40s Thursday and Friday.
.LONG TERM /SATURDAY THROUGH TUESDAY/...
As of 316 PM EST Tuesday...A shortwave will attempt to move
into the 500mb ridge and produce a slight chance for
precipitation but reinforcing ridge at the surface and limited
moisture will likely lead to some clouds but not much precip
Saturday into Saturday night.
More significant system will develop a closed surface low
Sunday night around the Ohio River Valley with large southern
stream 500mb low. Moisture feeding from Carolina coast will
bring PWATs around 1 inch into the North Country as negatively
tilted 500mb trough moves NEwd. This will result in warm air
aloft and possible mixed precip moving into the North Country
from south to north late Monday. Models differ on track of
primary surface low, affecting how much warm air moves into the
region. But GFS and ECMWF agree on strong low level jet of
50-65kts late Monday through Tuesday.
.AVIATION /00Z Wednesday THROUGH Sunday/...
Through 00Z Thursday...Conditions will deteriorate rather
quickly from VFR to to MVFR/IFR as wintry mix moves into the
area in the form of snow/sleet as well as some freezing rain
for New York stations. Conditions will remain around MVFR
through then end of the period even after the precipitation
begins to taper off after 15Z.
Winds will be southerly at 5-10 knots for most of the area with
KRUT seeing some gusts around 20 knots. KMSS will be the lone
exception as northeasterly flow stays locked in though the
period with winds 05-15 knots.
00Z Thursday through 00Z Friday...VFR with brief MVFR/IFR
00Z Friday through 00Z Monday...VFR, as a ridge of high pressure
will be over the region.
VT...Winter Weather Advisory until 1 PM EST Wednesday for
NY...Winter Weather Advisory until 7 AM EST Wednesday for NYZ029-
Winter Weather Advisory until 1 PM EST Wednesday for NYZ028-