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000 
FXUS61 KBTV 191206
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
706 AM EST Tue Nov 19 2019

.SYNOPSIS...
Freezing rain with perhaps some sleet mixing in currently 
spreading across the North Country this morning. This area of 
precipitation pushes eastward today, and eventually changes to 
snow or a mix of rain and snow. The precipitation will gradually
taper off this afternoon. Quieter weather is expected on 
Wednesday and Thursday but another storm system will move into 
the region on Friday. This system will likely bring a mix of 
rain and snow to the North Country.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
As of 638 AM EST Tuesday...Freezing rain continues across most
of our area, but have begun to see some snow mixing in. Models
continue to show precipitation changing to mainly snow by about
10am. No big changes for the 630 am update this morning.
Previous discussion follows. 

Area of precipitation associated with a surface trough between 
departing surface low and another weaker surface low centered 
near Lake Erie is moving across our area early this morning. As 
of 430 am, mainly seeing freezing rain, but as colder air moves 
in aloft associated with approaching upper level trough, will 
see precipitation change to snow or a mix of rain and snow as 
maximum temperatures rise to around the lower to upper 30s. 
Could see up to two tenths of an inch of ice accumulation before
the change over to snow. Then snow accumulations will be pretty
minor, a dusting to two inches. As previous forecaster 
mentioned, best frontogenesis and deformation will be south of 
our area, perhaps grazing our southern Vermont zones. 
Precipitation will taper off from west to east this afternoon. 
Not too much of an air mass change headed into the overnight, 
expect clouds to stick around so temperatures won't go too far. 
Minimum temperatures will range through the 20s. Another upper 
level trough pushes across the area on Wednesday bringing more 
chances for light rain and snow showers as upper level shortwave
moves across the area, especially our Vermont zones and 
especially the higher elevations. Maximum temperatures will 
range from the mid to upper 30s on Wednesday, therefore 
precipitation in the valleys should fall as rain while only the 
higher elevations see snow.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY/...
As of 405 AM EST Tuesday...Generally looking at quiet conditions mid-
week as upper level low pressure exits off the East Coast Wednesday
night and is replaced by an upper ridge and surface high pressure on
Thursday. Blocked upslope flow will keep a few snow showers around
the northern mountains early Wednesday night with just a dusting to
half inch of snow accumulation expected before we see some partial
clearing of skies early Thursday morning. Clouds build back in
quickly though as our next system approaches for Thursday night with
skies back to mostly cloudy by the days end. Temps will run slightly
below normal for the period with lows in the 20s and highs in the
30s to locally near 40 in southern areas.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
As of 405 AM EST Tuesday...Not a whole lot of weather to talk about
in the extended period with the exception of a strong cold front
passage on Friday. As the aforementioned surface high and upper
ridge shift east of the forecast area Thursday night, strong surface
low pressure will track Northeast from the Great Lakes to central
Quebec by sunrise Friday. The attending warm front extending
eastward from the low center will lift through the North Country
overnight into early Friday with light snow developing at the onset
but changing to rain by Friday morning as the boundary layer warms
above freezing. In the warm sector, a brief break in precip is
expected mid-day Friday, mainly across Vermont, until the cold front
swings through Friday afternoon and evening. Currently it appears
there are some weak signals for snow squalls along the frontal
passage which features a sharp temperature gradient in 40s ahead of
the boundary and 20s behind, and a decent low level wind field of
30-40kts at 925-850mb. What's lacking is instability so don't think
we'll see anything like we did last week, but a quick wet dusting to
half inch is certainly possible as rain showers change to snow
during the late afternoon and evening hours.

Looking forward to the weekend, 00Z global models are in agreement
showing high pressure dominating over the Northeast keeping a series
of cut-off lows well south of the region passing through the Ohio
Valley and mid-Atlantic states Sunday through Monday. While
conditions will be dry across the North Country, below normal temps
will persist with daily highs in the 30s and lows in the 20s.

&&

.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
Through 06Z Wednesday...Deterioration to mainly MVFR/IFR over
the next 24 hours as upper low pressure and light mixed
precipitation move through the region. Winds light and less 
than 10 kts through the period. Precipitation type quite tricky,
with patchy -ra/-fzdz from 06-10Z transitioning to a general 
-fzra/pl mix, then light snow/pl in the 10-14Z timeframe. Light
 mixed precipitation lifts out of the area in the 14-18Z
 timeframe. Only exception will be KMSS where precipitation 
 will be patchy/intermittent at best so only VCSH there. 
 Precipitation will end from west to east between 18-21z.

Outlook...

Wednesday: Mainly MVFR, with local IFR possible. Chance SHSN.
Wednesday Night: Mainly VFR, with areas MVFR possible. Slight
chance SHSN.
Thursday: Mainly VFR, with local MVFR possible. NO SIG WX.
Thursday Night: Mainly VFR, with local MVFR possible. Definite
SHRA, Chance SHSN.
Friday: Mainly MVFR, with local IFR possible. Chance SHRA,
Definite SHSN.
Friday Night: Mainly VFR, with areas MVFR possible. Slight chance
SHSN.
Saturday: VFR. Slight chance SHSN.

&&

.BTV WATCHES/WARNINGS/ADVISORIES...
VT...Winter Weather Advisory until 1 PM EST this afternoon for 
     VTZ001>012-016>019.
NY...Winter Weather Advisory until 1 PM EST this afternoon for 
     NYZ027-028-030-031-034-035.

&&

$$

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