Area Forecast Discussion
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FXUS61 KBTV 022030
Area Forecast Discussion
National Weather Service Burlington VT
330 PM EST Fri Dec 2 2016
An upper trough will move southeast from Canada overnight, and
will bring a chance of rain and snow showers. The region will
remain under cyclonic on Saturday with a chance for more rain
and snow showers. A ridge of high pressure will build into the
north country on Sunday, and will bring fair and dry weather to
the north country from Sunday through Tuesday.
.NEAR TERM /THROUGH SATURDAY/...
As of 330 PM EST Friday...An upper trough will move southeast
from Canada overnight, and will bring a chance of rain and snow
showers to the north country overnight. This upper trough will
bring colder air at the surface and aloft to the north country
overnight and Saturday. The higher elevations of the Adirondacks
and Green Mountains could see 1 to 3 inches of snow overnight.
Lows will be mainly in the 30s, except in the 20s over the
On Saturday, the north country will remain under cyclonic flow
from the departing surface low pressure area over the Canadian
maritimes. Will go with chance pops for rain and snow showers on
Saturday. Highs on Saturday will be mainly in the 30s.
.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY/...
As of 300 AM EST Friday...Then more of the same for Saturday as
we remain in northwesterly flow and a final upper shortwave
swings through the region. Mainly cloudy skies with solid pops
in the 40-60 percent range will be maintained, mainly across
elevated terrain where orographic forcing will aid in boundary
layer ascent supportive of snow shower activity. Considerably
drier weather is expected in the valleys however with just a
passing light rain or snow shower here or there. High
temperatures continue seasonably cool in the 30s. By Saturday
night clouds will hang tough in the mountains despite thinning
moisture as weakening northwesterly flow persists with weak high
pressure approaching from the Great Lakes. Valley locales
should see some partial clearing after midnight however. Pops
will continue to wane leaving just some scattered light snow
showers or flurries across the highest of elevations by sunrise
Sunday. Low temperatures mainly in the 20s.
By Sunday high pressure will build across the region with sunny to
partly sunny skies and light winds. Little airmass change is
expected. In fact mean 925 mb thermal profiles actually cool
slightly so high temperatures generally ranging through the 30s
looks reasonable once again despite the added insolation. Winds
light. Pops nil.
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
As of 300 AM EST Friday...Overall a fairly quiet period of
sensible weather is expected during the Monday/Tuesday time
frame with seasonably cool early December temperatures and only
low chances of light precipitation, mainly across our western
counties. Models remain generally consistent in tracking a
dampening shortwave trough through the area on Monday into
Monday evening with little fanfare. There will be a broad
increase in cloudiness, though with weakening dynamical upper
support and isentropic lift any precipitation should be light
and scattered at best, most focused across our northern New York
counties. By Tuesday high pressure returns to the region with
partial sunshine and light winds. Again, negligible airmass
change is expected with seasonal highs in the 30s both days and
overnight lows in the 20s to around 30.
Looking further out, this morning`s medium range guidance continues
to suggest the mean flow trends more amplified across the lower 48
from mid-week onward as the year`s first decent polar airmass dives
south into the Rockies and Northern Plains. This will eventually
drive cyclogenesis across the Southern Plains/northwestern Gulf
Coast which will track northeast toward the region. Still plenty of
uncertainty in regard to how quickly this system will consolidate
into a primary low pressure center with several solutions showing
some sort of lead energy and associated precipitation affecting the
area as soon as Tuesday night. At this point a blended solution
appears most reasonable given this uncertainty, and will concentrate
the bulk of higher precipitation chances during the Wednesday and
Thursday time frame. Still too early to confidently predict p-type,
though signals and synoptic pattern would suggest some sort of mix
and/or rain seems most probable at this point as warm advective
signatures increase solidly over time. Temperatures warm slightly
during this period as mean background flow trends southerly with
highs from the mid 30s to lower 40s or so, and lows in the mid 20s
to lower 30s.
.AVIATION /20Z Friday THROUGH Wednesday/...
Through 18Z Saturday...An upper trough will move through the
region overnight. Expecting rain and snow showers to gradually
change to snow showers overnight as colder air at the surface
and aloft moves into the region. Surface winds from the west-
southwest will also gradually shift to the northwest overnight,
as the upper trough moves through the region. Expecting areas of
MVFR ceilings, with some local pockets of IFR.
Outlook 18Z Saturday through Wednesday...
18Z Saturday through 12Z Sunday...Mix of VFR/MVFR with local
IFR possible at KSLK in scattered rain/snow showers.
12Z Sunday through 06Z Wednesday...Mainly VFR with high
pressure building in. Periods of MVFR ceilings possible,
especially at KMPV/KSLK.
06Z Wednesday through 00Z Thursday...areas of MVFR/IFR in rain
and snow showers.