Area Forecast Discussion
Issued by NWS Burlington, VT-- Highlight Changed Discussion --
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FXUS61 KBTV 290741
Area Forecast Discussion
National Weather Service Burlington VT
341 AM EDT Wed Mar 29 2017
A cold front will move through the North Country overnight with
a chance of rain or snow showers. There will be a slight chance
for rain and snow showers on Wednesday, mainly over the high
elevations of the Adirondacks and Green Mountains. A ridge of
high pressure will build into the region on Thursday with mostly
sunny skies expected. A low pressure area moving east across
the Ohio valley will bring mixed wintry precipitation to the
North Country late Friday into Saturday.
.NEAR TERM /THROUGH THURSDAY/...
As of 1108 PM EDT Tuesday...Patchy drizzle, isolated -RW, and low
ceilings persist across the North Country this evening, with
temps at 03Z mainly 34-38F. Main synoptic feature of note is
the relatively compact, vertically stacked low exiting east of
NJ. Main precipitation shield with this system will remain to
our south. However, as the low tracks ewd, will see increasing
N-NW winds, which will induce low-level CAA thru the remainder
of the overnight. Gradually cooling thermal profiles will allow
for a rain/snow mix as we move toward 04-05Z along the intl
border, and elsewhere after 06Z. Activity will be quite light
with orographics effects providing primary forcing mechanism.
Despite the low- level CAA, continued cloud cover will help to
keep temperatures up overnight with lows mainly in the lower 30s,
except in the 20s over the higher elevations.
The region will be under cold advection on Wednesday. expecting
a slight chance for some rain or snow showers on Wednesday,
mainly over the higher elevations of the Adirondacks and Green
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
-- Changed Discussion --As of 341 AM EDT Wednesday...Most active period of weather then
affects the region by late Thursday night and especially Friday
into Friday night as upper closed energy tracks east from the
Ohio Valley into the Mid Atlantic region. The forecast remains
quite complex in regard to precipitation timing, amounts and
type with lower boundary layer thermal profiles playing a
critical role through the period. This is not uncommon with
early spring systems with subtle changes of 1 to 2 degrees
either way potentially leading to large differences in sensible
weather. For now will maintain our prior idea of snows arriving
into our southwestern counties later Thursday night into mid
morning on Friday before a transition to all rain in lower
elevations, or rain/snow mix from 1000-2500 feet on Friday as
precipitation shield advances into the remainder of the forecast
area. At higher elevations above 2500 feet p-type may remain as
all snow. Negligible amounts of sleet or freezing rain is
expected. Lows Thursday night mainly in the 20s with afternoon
highs on Friday from 35 to 40 below 1500 feet and 30 to 35 above
Bulk of precipitation then affects the area Friday night as warm
thermal advection aloft will be peaking and as thermal profiles cool
slightly a transition to all snow is expected after midnight.
Amounts may be a bit tricky as flow trends southeasterly and some
slight shadowing effects may occur. Time will tell. I was also
cautious in leaning too high on our QPF given known model high bias
during warm thermal advective events. Nonetheless the potential will
exist for a light to moderate wet snow accumulation in many areas
with higher amounts possible in elevated southern terrain. Did lean
on the milder side of guidance given clouds and lack of appreciable
low level advection - mainly lower to mid 30s (upper 20s at
elevation). Please see our winter weather page at
www.weather.gov/btv/winter for specific accumulation forecasts and
By Saturday widespread light snows taper to scattered rain/snow
shower activity as system exits the Mid Atlantic coast and
gradually loses influence. Any additional snow accumulations
will be minor as late day temperatures top out in the upper 30s
to lower 40s.
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.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
-- Changed Discussion --As of 341 AM EDT Wednesday...Relatively quiet weather then
returns by later Saturday into early next week with mean high
pressure building back across the region. Any lingering
rain/snow shower activity will wane in coverage, becoming more
confined to northern higher terrain into Sunday as highs top out
in the 40s. Temperatures will be similar on Monday with dry
weather expected. The next threat of steadier precipitation
potentially arrives toward the middle of next week with chances
of rain and/or snow showers. Temperatures will remain at, or
slightly above seasonal early April norms.
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.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
Through 06Z Thursday...Variable flight conditions from VFR to
LIFR will continue through 12-13z before all sites lift to MVFR
except VFR at KMSS. Thereafter a gradual improvement at all
sites to VFR is expected by the afternoon. Areas of fog and
drizzle overnight generally dissipate after 12z as well, with
some lingering rain/snow showers across central/northern
portions of Vermont through about 18z. Winds calm/light
overnight trend to the north/northwest at 5-15kts after 12z with
some gusts up to 20kts possible from the Champlain Valley
eastward through Vermont.
Outlook 06Z Thursday through Sunday...
06Z Thursday through 12Z Thursday...Mainly VFR. Isolated MVFR
and showers over higher terrain of NE VT.
12Z Thursday through 12Z Friday...VFR under high pressure.
12Z Friday through 00Z Monday...MVFR/IFR in periods of rain and