Area Forecast Discussion
Issued by NWS Burlington, VT-- Highlight Changed Discussion --
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FXUS61 KBTV 281945
Area Forecast Discussion
National Weather Service Burlington VT
345 PM EDT Tue Mar 28 2017
Low pressure tracking eastward across central Quebec will push
a cold front through the North Country this afternoon with
scattered showers developing from mid-day through this evening.
Behind the front, some scattered snow showers are expected
tonight into Wednesday, with drier conditions on Thursday as a
ridge of high pressure builds over the region. Unsettled weather
returns for the end of the week and into the weekend though, as
another storm system will bring valley rain and mountain snow
to the area Friday into Saturday.
.NEAR TERM /THROUGH WEDNESDAY/...
As of 129 PM EDT Tuesday...Composite radar loop showing rain
showers associated with northern stream upper shortwave coming
across the Champlain valley at this time. Have lowered the pops
in some areas further south and west. Further south, composite
radar loop showing some showers associated with upper shortwave
over the mid Atlantic states moving into southern Vermont at
this time. Thus, will keep in a chance of showers there for the
remainder of this afternoon.
Previous Discussion...Little overall change from previous
forecast thinking as the North Country will be in between mid-
level troughs today, one to our south and another to our north.
Northern trough and associated surface low will sag southward
through the day dragging a cold front into the forecast area
this afternoon and tonight. Abundant low level moisture
currently over the area combined with some additional moisture
from the southern stream system and frontal lift will aid in
developing scattered rain showers across the region today.
Precip will come in 2 waves with the first round shifting from
the St. Lawrence Valley this morning into northern portions of
New York and the northern Champlain Valley before additional
showers develop across more of the forecast area this afternoon
and evening. Based on current upstream radar and modeled
reflectivity expect showers to be scattered in nature and hit or
miss in any one single location. Temps will continue to run
mild with highs ranging through the 40s with a couple of spot
For tonight, aforementioned cold front slips through the region
with and lingering precipitation transitioning from rain to snow
showers, especially across the higher terrain. Modeled Froude
numbers show increasing blocked flow overnight with winds
shifting to the northwest and this combined with the parent
upper trough and weak shortwave energy passing through supports
some locally enhanced precipitation across the western slopes of
the Greens backing up all the way into the northern Champlain
Valley late tonight into early Wednesday, before becoming
unblocked by Wednesday afternoon. Ptype will be all snow by this
time with low temps tonight around freezing, so some light
accumulations are possible, perhaps up to an inch in the lower
elevations and a couple inches over the high peaks. Temps rise
Wednesday afternoon into the mid 30s to low 40s so any precip
leftover by that time will transition back to a rain/snow mix.
.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
As of 340 AM EDT Tuesday....The upper trough and attendant
backside energy then depart east on Wednesday night with broad,
albeit short-lived ridging at lower and mid levels building
across the area later at night into Thursday. As such, any
northern mountain snow showers/flurries will gradually end
Wednesday night setting the stage for a partly to mostly sunny
day on Thursday. Low temperatures a bit tricky and will be
dependent on amount of clearing or lack thereof, but generally
stuck with blended guidance showing values in the 20s to locally
near 30 in the Champlain Valley and slightly cooler in northern
NY where clearing probabilities are higher. Thursday highs from
the upper 30s to mid 40s still look on track as advertised by
.LONG TERM /FRIDAY THROUGH TUESDAY/...
-- Changed Discussion --As of 345 PM EDT Tuesday...Snow expected to spread from north
to south across the North Country on Friday with warming
temperatures during the day in southerly flow changing snow to
mostly snow. Some enhancement of QPF on eastern slopes expected
with shadowing effects on leeward slopes and valleys. Heading
into Friday night/Saturday morning, warmer air aloft will result
in wintry mix starting over Northern NY and spreading eastward
into the Champlain Valley in the middle of the night. Northeast
Kingdom has best chance of remaining snow through Saturday
morning. Winds shift out of the north on Saturday as the main
coastal low pulls east and northern stream shortwave that
provided lift for wintry mix will move out of the area with
generally drying conditions Saturday into Sunday. NW upslope
precip possible through Sunday before surface high pressure
becomes the dominant feature through Tuesday.
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.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
Through 18Z Wednesday...Highly variable flight conditions with
scattered rain showers continue through the evening as a cold
front shifts into the region. VFR conditions over Vermont TAF
sites will deteriorate to MVFR this afternoon and evening with
brief period of IFR vsbys possible mainly in the afternoon. MVFR
conditions at KPBG will persist through Wednesday morning.
Further west, KMSS & KSLK continue to have LIFR conditions to
VLIFR possible, then gradually improving early to mid Wednesday
morning. Areas of fog development possible tonight, with MVFR-
IFR vsbys. Generally expect all terminals to see improvement on
Outlook 18Z Wednesday through Sunday...
18Z Wednesday through 00Z Thursday...MVFR/IFR in scattered
scattered rain/snow showers, mainly across central/northern
00Z Thursday through 12Z Thursday...Mainly VFR. Isolated snow
showers over higher terrain.
12Z Thursday through 12Z Friday...VFR under high pressure.
12Z Friday through 06Z Sunday...Areas of MVFR/IFR in rain and
06Z Sunday onward...VFR conditions under building high pressure.