Area Forecast Discussion
Issued by NWS Burlington, VT
FXUS61 KBTV 272003
Area Forecast Discussion
National Weather Service Burlington VT
403 PM EDT Thu Oct 27 2016
An upper level trough of low pressure will move across the region
tonight through Friday morning before exiting to our east Friday
afternoon. Widespread precipitation is expected tonight through
Friday morning before tapering off Friday afternoon. Temperatures
will remain below normal for this time of year on Friday and
continue right through the weekend. In addition...there will
continue to be the chance of showers on Saturday and Sunday.
.NEAR TERM /THROUGH FRIDAY/...
As of 338 PM EDT Thursday...Areal coverage of light precipitation
continues to increase in areal coverage over the area this
afternoon and this trend will continue through tonight as warm air
advection and an approaching upper level trough of low pressure
move into the region. Temperature scenario of readings struggling
to warm this afternoon has played out nicely and with larger
temperature-dew point spreads over Vermont...further cooling has
taken place with the onset of precipitation to produce more snow
than rain. Still looking at a dusting to 2 inches over all but the
Champlain Valley through this evening with snow at the higher
elevations. Champlain Valley should remain warm enough for
rain...but a few wet flakes could mix in.
Upper trough moves across the area on Friday. While exiting dynamic
support helps to decrease the areal coverage of precipitation...
northwest flow aloft develops and begins to enhance orographic
precipitation. This should keep accumulating snows going over the
higher terrain and generally rain showers at the lower elevations
with highs generally in the upper 30s to mid 40s.
.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/...
As of 342 PM EDT Thursday...A weak ridge will build in Friday
night as northwest flow will gradually shift to southerly flow.
Low level RH (<850mb) will still be greater than 95% while the
northwest flow remains and so I anticipate light showers to remain
in the upslope areas on the western slopes of the Greens and
Adirondacks due to the orographic lift. These showers however will
gradually come to an end as the low level moisture dissipatesby
Even with the loss of low level moisture there should still be
ample in RH in the 700-500mb range which will lead to fairly
consistent cloud cover overnight. The cloud cover should keep
temps from bottoming out, and so the forecast is a blend of
available guidance trended a bit warmer than MOS even as the winds
A weak low pressure system passes north of the border on Saturday
and the lack of any significant forcing will lead to much of the
area seeing light precip but no significant accumulations of rain.
Due to us sitting in the warm sector boundary layer temps are
warm enough to just be all rain across the North Country.
Southerly warm air advection will persist and temps should warm
into the upper 40s to near 50s in the Champlain Valley. Overnight
lows will be well above normal due to the warm air advection that
will persist through the weekend.
.LONG TERM /SUNDAY THROUGH THURSDAY/...
As of 401 PM EDT Thursday... High pressure begins to build in
behind that upper level trough as it passes to the North. This
will lead to dry weather to begin the work week. The next
"feature" that will impact the North Country is a low pressure
system tracks up the through the Great Lakes towards James Bay
which does the unfortunate thing by brining a dry warm front
through the North country. So we will be looking at a gradual warm
up with temps moderating into the mid to upper 50s Tuesday into
Wednesday under continued southerly flow.
.AVIATION /20Z Thursday THROUGH Tuesday/...
Through 18z Friday...Current VFR conditions will quickly lower to
MVFR by 20z as light precipitation moves into the region.
Precipitation should be a mix of rain and snow at the lower
elevations before becoming all rain after 00z...with snow in the
mountains. Winds will be from the east and southeast with gusts in
the 15 to 25 knot range through about 12z...then shift around to
the northwest after 12z. At this point...ceilings and visibilities
will lower into the IFR and MVFR categories for the remainder of
Outlook 18z Friday through Tuesday...Conditions will gradually
improve back to MVFR and VFR after 18z Friday as precipitation
comes to an end. A warm front feature lifting across our taf sites
on Saturday morning will shift the winds to the southwest with
some scattered showers possible...especially mss/slk. Expecting
mainly vfr conditions with intervals of mvfr cigs possible across
northern NY taf sites on Saturday. Gusty southwest up to 35 knots
are possible at MSS with 30 knots expected at SLK/BTV on Saturday.
Another wind shift to the west/northwest will occur Sat Night into
Sunday with additional scattered showers. Drier conditions with
vfr flight conditions for Sunday afternoon into Monday.
As of 255 PM Thursday...Several bouts of strong winds and rough
conditions are expected on the lake the next few days. South/southeast
winds of 15 to 25 knots are expected through late evening, before
diminishing after midnight. During the day Friday, winds will
switch to the northwest and strengthen, with winds approaching 25
knots for the afternoon and early evening. Winds will diminish
Friday night, but then switch to southerly on Saturday morning.
Winds will quickly increase again to around 25 knots during the
mid-day hours. These strong and gusty winds will result in choppy
conditions out on the lake.