Area Forecast Discussion
Issued by NWS Burlington, VT-- Remove Highlighting --
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FXUS61 KBTV 220826
Area Forecast Discussion
National Weather Service Burlington VT
426 AM EDT Wed Mar 22 2017
An arctic cold front moving across Vermont and New York during
the pre- dawn hours will usher in much colder air today with
strong and gusty northwesterly winds. Flurries will end this
morning, with a few icy spots possible on roadways. Afternoon
temperatures will generally range from the upper teens to lower
20s. High pressure in place for Thursday will result in lighter
winds and moderating temperatures. A warm front will arrive on
Friday with increasing clouds and mixed wintry precipitation
across the North Country.
.NEAR TERM /THROUGH THURSDAY/...
As of 159 AM EDT Wednesday...Arctic cold front is passing thru
BTV at 06Z with ongoing snow showers and localized snow
squalls. Winds in the wake of the front are gusting 25-33kts
(including 32kt at BTV), and strong low-level CAA will maintain
good low-level mixing and gusty winds to 30kts from the NW
throughout most of the day. It appears we`ll remain below wind
advisory criteria, but will still be a rather brisk day for late
March with wind chills zero to 10 below in many spots this
afternoon. Main concern early this morning is for some icy spots
on roads with "flash freeze" situation as temperatures rapidly
fall below freezing during the pre-dawn period, with snow
initially melting on relatively warm paved surfaces. We`ll
handle with a Special Weather Statement as we get closer to the
morning commute time frame to highlight for the traveling public.
Temp at 06Z still 36F at BTV but already down to 23F upstream
at MSS...and 850mb temps fall to -21C to -23C across our
forecast area by 18Z this afternoon. Thus, will see rapidly
falling temps through the morning and not much recovery this
Will continue to see some mountain flurries with upslope flow
conditions, but gradual drying will occur with decreasing clouds
from NW-SE away from the summits during the daylight hrs.
Should see mostly sunny conditions for the afternoon hrs, except
partly sunny across far n-central into nern VT with orographic
Strong surface anticyclone (1038mb) begins to move in from the
Great Lakes region tonight and Thursday, bringing diminishing
winds and mostly clear skies. Lows tonight generally in the
single digits above zero, except in the lower teens in the vcnty
of Lake Champlain. Some modest recovery on temps tomorrow aided
by relatively high late March sun angle, with highs upr 20s to
lower 30s and lighter nw winds 5-10 mph.
.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
-- Changed Discussion --As of 356 AM EDT Wednesday....Thursday night will remain quiet
with strong sfc ridge shifting eastward into the Gulf of Maine.
Will see developing south-southwest winds and increasing mid-
upper level clouds combine to mitigate radiational cooling a
bit. Should see lows in the lower 20s in the immediate vicinity
of Lake Champlain, and mainly in the teens elsewhere. Most of
the temperature drop will occur during the first half of the
night before leveling off with thickening clouds from SW-NE.
A more active weather pattern develops starting on Friday, as a
warm front moves into the region from the SW. It appears snow
will develop Friday morning, before changing to a mix of sleet
and rain during the afternoon and evening hrs. Could see some
impacts to travel in spots, mainly away from the Champlain
Valley as moderately strong S-SW winds (15-25 mph, gusts 35mph)
allow temperatures to climb through the 30s by Friday afternoon.
Could see a minimal accumulation of snow/sleet in the Champlain
Valley, with 1-3" across the nrn Adirondacks and central/ern
VT...where subfreezing air will likely hold on a bit longer.
Have started a mention in the morning Hazardous Weather Outlook.
It appears initial surge of low-level WAA and associated 700mb
shortwave trough will slide to our east Friday night. At the
same time, the GFS/ECMWF have been trending toward a stronger
sfc ridge to our north across Ontario and wrn Quebec. It`s
likely that the sfc front will stall with an east-west
orientation in vcnty of nrn NY/VT Friday night, with abundant
low clouds and possible light rain/drizzle. It`s possible that
the front may settle south a bit if there is a shallow push of
colder air from srn Quebec. That could have an impact on
precipitation type later Friday night, though again, any precip
during this time frame is expected to be light. Have shown lows
in the upr 20s to lower 30s for now, and will continue to
monitor model trends with regard to positional of the quasi-
-- End Changed Discussion --
.LONG TERM /SATURDAY THROUGH TUESDAY/...
-- Changed Discussion --As of 356 AM EDT Wednesday...Greater than average run-to-run
model variance during the long-term period. Anticipate a W-E
quasi- stationary front across the North Country Saturday
morning, with latest 00Z GFS/ECMWF suggesting a shallow push of
colder air/north winds associated with strong anticyclone to our
north. This should result in the frontal zone sagging to the
south during the day Saturday into Saturday night. If those
trends hold, should see diminishing chances for precipitation,
and even some partial clearing across nrn areas with drier air
moving in from the N-NE. Attm, showing just 20-30 PoPs across
the Adirondacks into s-central VT for possible -RW/-SW on
Saturday. Highs on Saturday expected in the mid-upr 30s north,
but possibly low-mid 40s south depending on exact trends with
the frontal boundary.
Strong surface high pressure across central Quebec should keep
us relatively dry Saturday night thru the first half of Sunday.
Next shortwave trough in the Ohio Valley may result in the next
surge of low- level WAA and isentropic lift as winds turn S-SW
across our area later Sunday into Monday. If bndry retreats nwd
as a warm front, may again see a period of mixed wintry
precipitation, with snow/sleet trending toward mainly rain for
the daylight hrs Monday. Again, greater than normal degree of
variance in the 00z NWP model suite, so we will continue to
-- End Changed Discussion --
.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
Through 12Z Thursday...A strong arctic cold front will pass
through the region early this morning bringing 1-2SM -SHSN thru
08Z, and NWLY wind gusts of 28-32kts. Improving back to VFR
with gradual clearing during the daylight hrs, but will continue
to see gusts 25-30kts from the NW thru sunset today before
gradually diminishing tonight. HIR TRRN will remain OBSCD thru
11-12Z this morning.
00Z Thursday through Sunday...
12Z Thursday through 12Z Friday - VFR/high pressure.
12Z Friday through Sunday - VFR/MVFR/IFR in mixed wintry