020
FXUS61 KBTV 241908
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
308 PM EDT Tue Mar 24 2026
.WHAT HAS CHANGED...
As of 308 PM EDT Tuesday...
Winds and temperatures trended upward somewhat on Thursday.
&&
.KEY MESSAGES...
As of 308 PM EDT Tuesday...
1. Isolated to scattered snow showers tonight, primarily in
higher terrain, then additional, spotty light precipitation
Wednesday night trending towards rain.
2. Sharp river rises expected Thursday night into Friday in
response to a brief higher elevation thaw and widespread rain.
3. Unseasonably cold start to the weekend, trending back to
near normal for next week with unsettled conditions continuing.
&&
.DISCUSSION...
As of 308 PM EDT Tuesday...
KEY MESSAGE 1: A decaying cold front will amble eastward into northern
New York and Vermont tonight. Chances of snow showers generally are
greatest from 7 PM to 9 PM in New York and between 9 PM and midnight
in Vermont. While the upper level dynamics are impressive with both
water vapor imagery and progged winds showing a good setup for upper
level divergence ahead of the front, moisture will be lacking
especially without a boost of substantial surface convergence. A
very minor wind shift from southwesterly to westerly will occur with
the passage of the front with only neutral thickness advection as
colder air largely remains displaced well to our north overnight
into Wednesday. A narrow zone of deep moisture will be
associated with the front, and then lingering snow showers
should have shallow cloud tops still sufficiently cold to
saturate the snow growth zone, such that some isolated snow
showers will persist towards daybreak, especially in the western
Adirondacks and near the spine of the Green Mountains. The
westerly 925-850 millibar flow will lead to some downsloping,
although again with the limited cold air advection do not expect
winds to gust significantly, mainly in the 25 to 30 MPH range
at greatest. Most of tomorrow will be dry and seasonable, with
temperatures ranging from the mid 30 to mid 40s for most
locations during the afternoon.
While there are no significant weather concerns with the next,
light precipitation event tomorrow night, there are some
localized hazards to note. Both the HRRR explicit precipitation
type and the dominant precipitation type output from the GFS
show at least light/transient freezing rain across the St.
Lawrence Valley and pockets of far northeastern Vermont.
Measurable freezing rain is unlikely at this time, with greatest
chance of a glaze of ice as often the case near Massena, New
York. Some light snow is also possible at the onset of
precipitation, especially in north central/eastern Vermont and
the Adirondacks, before precipitation type changes to light
rain during the nighttime hours; probability of weather type
quickly trends to liquid after midnight with push of southerly
flow. Due to combination of light amounts of precipitation and
this warmup, hazardous morning travel Thursday morning is
unlikely.
KEY MESSAGE 2: Thursday will be a warmer and breezy day. Southerly
flow will likely result in channeled, locally gusty winds. Wind
gusts in the 30 to 35 MPH range are favored at this time with
lack of a strong pressure gradient. It is questionable how
widespread breezy conditions will be with coverage of steady
rain uncertain associated a fast moving shortwave embedded in
the westerly flow aloft. Some model guidance keeps it farther
north such that much of the daytime hours on Thursday are dry.
The consensus idea is higher chances of rain as you go
northward, and the stability associated with the rain will
limit breeziness. Any sunshine will also help boost
temperatures, which are still expected to climb into the 40s and
50s through the day. 925 millibar temperatures are progged to
rise above the 90th percentile with values near 50 degrees such
that any extended dry periods and associated mixing will lead to
valley temperatures approaching 60.
The combination of a relatively brief but substantial thaw with
higher elevations becoming mild, breezy, and wet will lead to
significant snowmelt (potential for an inch or greater liquid
equivalent snow) Thursday through Thursday night. The combination of
widespread rainfall near 0.5" and this type of snowmelt will lead to
sharp river rises late Thursday into Friday morning, but with low
within banks, with a low chance of action stage at various rivers
including the Lamoille and Winooski. The only mainstem river
forecast we continue to highlight with somewhat elevated chance of
reaching flood stage (greater than 10% but less than 30% per GEFS)
is the East Branch Ausable River. The latest data suggests most
likely snowmelt in the Ausable Basin of just over a 0.5" of SWE with
about 0.75" of rainfall. Some of the warmer and breezier scenarios
suggest efficient snowmelt that could exceed 1" of SWE specifically
in this basin, although there is a lot of spread in temperatures
through the period.
Regardless of maximum temperatures, they will fall quickly Friday
morning putting an end to the thaw as a sharp cold front passes
through. Light snow accumulations are possible, although the fast
departure of the low pressure system and limited cyclonic flow
behind the front points to limited upslope potential and only brief
window where moisture and thermal profiles support snow. An early
look at Froude numbers suggests ideal blocked northwest flow
immediately behind the front for the western slopes, but
temperatures may be too slow too cool given how warm it will be out
ahead of the front for any meaningful accumulations outside of the
mountains.
KEY MESSAGE 3: Behind the end of week cold front, temperatures will be
10-15 degrees below normal for the weekend. Temperatures will fall
Friday night into the single digits to low teens for overnight lows.
Some locations in the Adirondacks and Northeast Kingdom may approach
0 degrees. On Saturday, temperatures will struggle to reach the
freezing mark with strong northwest caa, with highs in the mid to
upper 20s across northern New York and east o the Greens, and low
30s in the Champlain Valley and southern Vermont. With the northwest
caa, winds will be breezy on Saturday with winds around 10 mph, with
occasional gusts 15-20 mph, mainly across northern New York and the
higher terrain. Thankfully, this deep unseasonable cold will be
short lived with a trend back to normal by Monday as we will
transition to more zonal flow. Highs will rise towards the low to
mid 40s on Monday with perhaps a few places reaching 50 in southern
Vermont. This warm up with be accompanied by a shortwave which could
bring some shower chances Monday into Tuesday. Models remain split
both in timing and location. The GFS depicts a more moist system
overhead of the area with mountain snow and valley rains, whereas
the EURO model depicts a more northerly tracked, drier system with
less precipitation. All in all, confidence is increasing in a
blustery Monday with a tightening pressure and thermal gradient
across the region as the shortwave passes through. DESI NBM
probabilities depict a 30-50% chance for 25 mph wind gusts for the
south to north oriented valleys and higher terrain. Given the
continued uncertainty have continued with the current WPC forecast
for the period.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
Through 18Z Wednesday...Other than some high stratus building
from the west, the next 6 hours will see prevailing VFR for for
most sites with mainly light southwest-west winds under 10
knots. A few occasional gusts between 10-20 knots will be
possible at SLK/MSS/PBG this afternoon. Winds will continue to
be mainly westerly overnight with potential gusts 2- 25kts at
PBG from downsloping this evening. A weak trough will bring a
few chances for light and brief snow showers this evening mainly
between 00-04Z. Confidence remains low on overall coverage of
the showers and whether terminals will be impacted, and thus
have used PROB30 groups where confidence is higher than other
terminals. A limiting factor will be dry surface air which could
lead to more virga. Any showers could have the potential to
briefly reduce visibilities to 4SM, outside of SLK. SLK will
have the best chances for any prevailing showers and
visibilities due to increased terrain influences. The trough
looks to wash out across the Adirondacks and central Greens
which could keep some low level moisture around at SLK/EFK/MPV
into tomorrow morning with prolonged chances for light snow and
mist. As the trough swings through the areas from west to east,
ceilings will trend towards 3000-5000ft agl this evening and
into tonight. Ceilings may further lower to MVFR at SLK/EFK/MPV
intermittently overnight. More prevailing MVFR could be possible
by tomorrow morning as the boundary washes out at all sites for
a brief few hours, before clouds trend towards scattered by 18Z
tomorrow.
Outlook...
Wednesday Night: Mainly VFR, with local MVFR possible. Chance
SHRA, Chance SHSN.
Thursday: Mainly VFR, with areas MVFR possible. Chance SHRA.
Thursday Night: Mainly MVFR, with local IFR possible. Definite
SHRA, Chance SHSN.
Friday: VFR. NO SIG WX.
Friday Night: VFR. NO SIG WX.
Saturday: VFR. NO SIG WX.
Saturday Night: Mainly VFR, with local MVFR possible. Slight
chance SHSN.
Sunday: VFR. NO SIG WX.
&&
.EQUIPMENT...
The NOAA Weather Radio Transmitter on Mt. Mansfield is
experiencing an outage. We`re working to determine the cause and
do not have an estimated return to service at this time.
In Franklin County, New York, the Parishville transmitter may
be used as an alternative. For the southern Champlain Valley,
Grandpa`s Knob may be used as an alternative. For Lamoille and
Washington Counties in Vermont, the Burke transmitter may be
used as an alternative. For additional information on NOAA
Weather Radio, visit weather.gov/nwr.
The Colchester Reef meteorological station is out of service.
This site is not serviced by the NWS and there isn`t an
estimated return to service at present. Please contact us if you
observe winds significantly deviating from the recreational
forecast.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
WHAT HAS CHANGED...Kutikoff
DISCUSSION...Danzig/Kutikoff
AVIATION...Danzig
EQUIPMENT...NWS BTV
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