Swanton, Vermont 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

722
FXUS61 KBTV 130457
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
1157 PM EST Tue Nov 12 2024

.SYNOPSIS...
Gusty winds will continue into this evening with colder air
filtering into the North Country. Widespread freezes are expected
tonight and tomorrow night with temperatures only warming into the
upper 30s and lower 40s for Wednesday. The next chances for
precipitation will be Friday into Saturday as an upper low tracks
northwestward off the New England coast.

&&

.NEAR TERM /THROUGH THURSDAY/...
As of 919 PM EST Tuesday...Winds continue to make their steady
decrease in speeds. We still remain a little mixed, and
temperatures have been a little slow to start cooling.
Fortunately, the area of clouds that blossomed earlier has
thinned enough that it no longer casts further doubt to the
overnight lows, and so only tweaked the diurnal curve with no
change to the going low temperature forecast. Have a great
night!

Gusts 20-30 mph this evening will slow overnight with expected
decoupling of SFC winds resulting in a sharp radiation
inversion. Freezing temperatures in the 20s will be widespread
with teens likely in the Adirondacks and northeastern Vermont.
Very little in the way of warming is expected for Wednesday with
much lighter winds and temperatures warming only into the upper
30s to low 40s. Clear skies and light winds Wednesday night
will promote strong radiational cooling with temperatures even
colder Wednesday night. Teens and low/mid 20s are expected for
most spots with some single digits possible for colder hollows
in the Adirondacks.

Some flurries over and around Lake Champlain should be expected due
to a strong upward moisture flux caused by a 10-20 degree
temperature differential from the water to the air. This will mainly
be overnight tonight and Wednesday when thermal contrast is largest.

&&

.SHORT TERM /THURSDAY NIGHT/...
As of 336 PM EST Tuesday...Another sunny day is expected on Thursday,
with perhaps a touch of low cloud cover on the eastern upslope side
of the Adirondacks in with Lake Champlain influence and easterly
winds. After a seasonably cold start, steady warming will occur with
as the nocturnal boundary layer mixes out to become modestly deep
for the late fall season. As such, temperatures will recover into
the low to mid 40s for most locations at or below 1500 feet
elevation, and typically colder at elevation. Note that 850 millibar
temperatures look steady near 1 to 3 celsius such that mountain
summit temperatures look fairly steady in the mid to upper 30s.
Combined with light winds, it should be a fairly comfortable day
from a recreational standpoint, as well. While it largely will not
affect temperatures, quite a bit of translucent cirrus is expected
to mute the blue sky. These high clouds will tend to be thicker in
western portions of the region.

The strong ridge situated overhead will weaken Thursday night as it
gets squeezed by a retrograding storm over the northern Atlantic
Ocean and a wave passing to our southwest which had brought us the
cirrus. Overall it seems we`ll see little impact from either system
during this period. However, if the ocean storm retrogrades on the
faster side, we`ll see an influx of northerly winds under a growing
pressure gradient. This scenario would more likely affect eastern
Vermont than points west of the Green Mountains and across northern
New York, and limit cooling. Overall, we`ll have another cold night
with light/calm winds, but lows will be moderated a bit from the
previous night and most commonly in the upper teens to mid 20s.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
As of 336 PM EST Tuesday...There are relatively large ranges in
likely high temperatures on Friday, but overall it looks seasonably
cool. For example, the current 25th to 75th percentile range for
Montpelier is 36 to 43 with a deterministic temperature of 44. This
large range and colder than expected values is probably due to
uncertainty in light precipitation and associated cloudiness. There
are substantial model differences in how the low pressure area
retrograding towards us will interact with the trough passing to our
south. Regardless, even the very wettest solutions suggest
precipitation will be on the light side, as the ocean storm does not
get pulled far enough to the west before advancing to the east again
on Saturday.

Greatest chances of widespread precipitation peaks Friday night, but
even then chances are mainly under 60%, greatest in northeastern
Vermont. There will probably be a sharp gradient with no
precipitation over northern New York and low chances over
southern/western portions of Vermont. Precipitation type is also a
question mark. There are a lot of ensemble members showing light
freezing rain as the dominant precipitation type, consistent with a
warm layer aloft and shallow refreeze layer. However, the relatively
coarse resolution both temporally and vertically of this data and
unfavorable meteorological setup for freezing rain suggests keeping
precipitation type just rain or snow at this time.

Precipitation chances dwindle to near zero by Sunday as strong
ridging returns from the west. Spread in temperatures increases
again early next week as the pattern generally looks to favor warmer
conditions but with renewed chances of rain showers. With
differences in timing of frontal systems and the related cloud
cover, the degree to which we warm up is uncertain. Low level
temperatures and thermal advection looks to be generally westerly
with Pacific type of air masses favored with limited polar
influence. So chances for snow remain low, especially outside of the
high terrain.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
Through 06Z Thursday...Winds continue to diminish with just a
few puffs of northwesterly winds in excess of 10 knots. Winds
will continue to diminish through the TAF period with
northwesterly winds of 5-8 knots becoming light and variable by
00Z Thursday. Skies will generally be clear through the TAF
period but some lake effect clouds off of lake champlain may
bring a few low clouds (around 4000 ft) to KBTV and KPBG tonight
and again Thursday night.


Outlook...

Wednesday Night: VFR. NO SIG WX.
Thursday: VFR. NO SIG WX.
Thursday Night: VFR. NO SIG WX.
Friday: VFR. Chance RA, Chance SN.
Friday Night: Mainly VFR, with local MVFR possible. Chance SN,
Chance RA.
Saturday: Mainly VFR, with areas MVFR possible. Chance RA.
Saturday Night: Mainly VFR, with areas MVFR possible. NO SIG WX.
Sunday: VFR. NO SIG WX.

&&

.FIRE WEATHER...
Strong northwesterly winds 15-25 mph with gusts 30-40 mph are
expected through this evening behind the cold front that passed
earlier. Cool temperatures are expected to keep RH values above
critical thresholds, but fuels remain very dry across portions
of southern and central Vermont. This, combined with the gusty
winds, will have an impact on fire weather conditions today. If
any fires were to start, the weather and fuel conditions could
cause fires to quickly get out of control and be difficult to
contain.

&&

.MARINE...
A Lake Wind Advisory remains in effect for Lake Champlain into
this evening for northwesterly winds 15-20 knots sustained and
gusts 25-30 knots across all three sections of the lake. Wave
heights will be in the 3 to 6 feet range this morning. Winds
will slow after 7 PM allowing waves to begin to subside.

&&

.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.

&&

$$
SYNOPSIS...Boyd
NEAR TERM...Boyd/Haynes
SHORT TERM...Kutikoff
LONG TERM...Kutikoff
AVIATION...Clay
FIRE WEATHER...Team BTV
MARINE...Team BTV