Area Forecast Discussion
Issued by NWS Burlington, VT-- Highlight Changed Discussion --
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FXUS61 KBTV 282334
Area Forecast Discussion
National Weather Service Burlington VT
634 PM EST Mon Nov 28 2016
Quiet weather this evening will give way to increasing clouds and
periods of light precipitation by Tuesday, and again by later
Wednesday into Wednesday night. Some light mixed precipitation will
be possible for a few hours Tuesday morning, especially across
eastern Vermont where a light glaze of ice will be possible on area
roads. Temperatures will trend seasonably mild by later tomorrow
into Wednesday before trending cooler with scattered rain and snow
shower activity to round out the late week time frame.
.NEAR TERM /THROUGH TUESDAY/...
As of 613 PM EST Monday...No significant changes for 630 pm
update. Have adjusted forecast to reflect current observations
and satellite trends. Previous discussion follows.
By tonight well advertised warm occlusion pushes bodily north
and east toward the region with steadier light precipitation
arriving in earnest across the western half of the forecast area
by sunrise and across the remainder of the area by mid-morning.
With mainly clear skies through the first half of the night
feel many areas will radiate quite well so continued idea of
minimum temperatures in the lower to mid 20s northeast, mid 20s
to around 30 in western VT/Dacks, and in the lower 30s SLV. As
precipitation arrives, a 1-3 hour potential of mixed p-type
concerns will exist across northern NY, and a tad longer across
eastern VT where progs still show some minor icing issues will
be possible. Accordingly a Freezing Rain Advisory will be
issued for this area during the 6 am to noon time frame. As
boundary layer continues to slowly warm, any mixed precipitation
should transition to light rain in all areas by early afternoon.
As front lifts north and east through the area, steadier light
rain will begin to taper off across our western counties by mid
to late afternoon leaving just some scattered light shower
activity here and there. Temperatures again tricky depending on
pbl mixing and eventual placement of front, though mid to upper
30s across eastern VT, lower to mid 40s Champlain Valley, Dacks,
northern SLV, and lower 40s Southern SLV still appear
reasonable at this time.
.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY/...
As of 205 PM EST Monday...By Tuesday evening the occluded low
will push the precip out of the North Country as dry air works
in behind the warm front. Temps by Tuesday late will be warm
enough to support all rain with max layer temps pushing 4C- 5C
in the 925-700mb layer. I agree with the previous forecaster
there there will likely be periods of drizzle mixed in late
Tuesday night with the saturated RH layer becoming rather
shallow but didn`t have the confidence on timing because 12z
guidance is showing the precip lagging behind 2-3 hours slower
than the 00z suite so given the slight delay I just went with
all light rain showers.
By midnight Tuesday conditions should be dry yet with the
strong warm air advection and cloudy skies expect temps to stay
warmer than normal only falling to the upper 30s to lower 40s.
The second wave of precip lifts towards the north as a secondary
low pressure system begins to develop over the mid Atlantic
region and gradually moves towards New England. With above
normal mild temps expect all rain with the second precip event
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
As of 235 PM EST Monday...Unsettled weather will be the theme
of the extended forecast as low pressure will persist until the
Wednesday night expect the rain to still be falling however we may
see a transition to heavy wet snow at elevations above 2500ft
as temps slowly begin to cool overnight. Total accumulations
across the North Country are expected to be near 0.50" for both
events for Northern New York and range from 0.75"-1.5" for the
combined events across Vermont with the higher rainfall totals
across the southern locations. The main shift in the guidance
was to bring the bulk of the heaviest precip for the Wednesday
system further south over the Catskills with slightly smaller
precip totals over the Greens and the rest of southern Vermont.
The combination of both events, and the warmer temperatures
will mean that much of the snowpack in the higher elevations
will melt and runoff into the rivers. Modest 2-3 foot rises in
the rivers are expected with all of the water expected to
remain in the banks and no flooding expected.
For the remainder of the week and into the weekend, the upper
level low will slowly push towards the Northeast. This results
in seasonable temperatures with highs in the 30s and lows in the
20s. Copious amounts of low/mid level moisture with marginal
forcing will lead to several periods of off and on orographic
rain/snow showers under west/northwest synoptic flow each day.
.AVIATION /00Z Tuesday THROUGH Saturday/...
-- Changed Discussion --Through 00Z Wednesday...Changeable aviation conditions
expected over the next 12 to 24 hours with all sites having vfr
through 10z Tuesday. Rain mixed with sleet and freezing rain at
mpv/slk develops between 10z-14z Tuesday...with any mix quickly
changing to a cold rain by 15z at mpv/slk...with minimum icing
expected. Vis will range btwn 4-6 sm in band of rain with
elements of heavier showers possible...and cigs will lower to
mvfr...especially at mpv/pbg/slk/mss. Downslope southeast winds
should limit mvfr cigs at btv/rut through most of the day.
Localized gusty winds to 25 knots at rutland is forecasted
btween 14-21z tuesday...with areas of low level wind shear and
turbulence possible at other sites. Clouds continue to lower
with some potential ifr toward tuesday evening at mpv/slk.
Outlook 00Z Wednesday through Saturday...
Expecting a mix of conditions Tuesday Night into Weds with MVFR
cigs at rut/btv with some ifr possible as low level moisture
increases at slk/mpv/pbg/mss...with areas of drizzle and br in
the mountains taf sites. Plenty of clouds with mvfr conditions
prevail thru weds morning...before more rain showers arrive weds
aftn into thurs with periods of ifr cigs/vis possible. Unsettled
weather with showers will continue for Thursday....with some
mountains snow showers possible Thursday night into the
weekend...especially mpv/slk. Mainly mvfr cigs expected with
some brief periods of ifr possible in any snow shower activity.
-- End Changed Discussion --
VT...Freezing Rain Advisory from 6 AM to 1 PM EST Tuesday for