043
FXUS61 KBTV 121435
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
935 AM EST Wed Feb 12 2025

.SYNOPSIS...
Colder and drier conditions will briefly return today, then a
complex winter storm will bring a variety of weather including
wintry mixed precipitation, plain rain, and gusty winds to the
region tonight through Thursday. Yet another period of colder
conditions follows Thursday night into Friday. Our active weather
pattern resumes over the weekend with a prolonged period of snow or
wintry mixed precipitation.

&&

.NEAR TERM /THROUGH THURSDAY/...
As of 935 AM EST Wednesday...Some minor changes needed with
this update based on the latest observations, especially with
sky cover and temperature. Relatedly, there is a persistent
stratus deck in portions of the Champlain Valley and a bit
stronger north/northwest winds in the wide valleys, resulting in
wind chills as low as 13 below zero in Massena. Sky cover
generally is variable, with sunny skies in much of the rest of
northern Vermont and northern New York, but high clouds have
moved into southern areas while a mix of lower and high clouds
stream in from the west this morning. All of this should lead
towards a trend towards partly sunny skies areawide as stratus
eventually scatters out.

Previous discussion...Winter Weather Advisories have been
expanded to include the St Lawrence Valley along with all of south
central Vermont. Long story short, the warmer trend continues with
this model suite, bringing the wintry mix further to the north and
west. Full details below.

First...today will be the quiet ahead of the storm with a brief
break in the precipitation. We`ll start out with a mix of sun and
clouds, but any sunshine will quickly be overtaken by incoming
mid/high clouds ahead of our next storm system. Highs will range
from the mid teens in the north to the mid/upper 20s south.

Models continue to be in pretty good agreement with the overall set
up for our incoming messy storm system. Snow will spread in from
southwest to northeast overnight tonight as low pressure lifts from
the Ohio River Valley toward the St Lawrence River. As this primary
low traverses just to the west of the St Lawrence River during the
day Thursday, a secondary low will start to develop somewhere over
southern New England, moving into the Gulf of Maine and eventually
into the Bay of Fundy. Although this overall setup seems certain,
there`s still plenty of uncertainty in the details, and small scale
changes in the strength and/or track of either low could have
relatively big impacts in precipitation type and amounts. Still, as
mentioned above, the 00z model suite has continued to show a more
widespread intrusion of warm air, as a strong 850mb S/SE jet lifts
over New England ahead of the primary low. The NAM continues to be
the warmest solution, the GFS is the coldest, with the CMC and ECWMF
somewhere in the middle. We`re now in the time scale of some of the
other hi-res guidance such as the HRRR/HREF, and these seem to favor
the NAM`s solution. Still, we`re hesitant to bite off on the warmest
models at this point, but have trended that way, using a blend of
the NAM and CMC for the precipitation type with this forecast
package.

Steady snow spreads in tonight, and it could be heavy at times,
particularly in the St Lawrence Valley where snowfall rates of 0.5-1
in/hr are possible. Rates will be lighter as one heads eastward,
especially along the western sides of the Adirondacks/Greens/far
northeast VT due to downsloping of the aforementioned jet. After
some initial cooling, temperatures will hold steady and likely rise
overnight, so fluffy snow will trend towards wetter/slushier snow by
daybreak Thursday. The warm intrusion starts to edge into the
Adirondacks/southern VT late tonight, so expect we`ll start to see
sleet mix in with the snow. This mixed area will continue to spread
to the northeast through Thursday morning, reaching as far north as
the northern Champlain Valley and eventually into the Northeast
Kingdom. Snow/sleet will eventually mix with freezing rain as the
warm nose depth increases, with the northern St Lawrence Valley, and
sheltered locations in the Adirondacks and along/east of the central
and southern Greens the most likely to hold onto enough cold air at
the surface to remain freezing rain/sleet. Areas immediately along
the international border have the best chance of remaining all snow,
particularly the far northern St Lawrence Valley, though some
guidance has even those locations seeing at least a period of wintry
mix. Surface temperatures will warm into the mid and even upper 30s
along the western slopes of the Adirondacks, into the Champlain
Valley, and portions of the CT River Valley, and these spots could
well turn over to just plain rain for a time around midday Thursday.
As we get past noon time, the steadier precipitation will turn
toward showers as the dry slot crosses into our area. Meanwhile,
south/southeast flow will turn to the west/northwest as the primary
low moves to our northeast. The cooling of the column will allow any
wintry mix to turn over to just plain rain or snow based on surface
temperature, and then eventually just snow by Thursday evening. By
the time all is said and done, snowfall totals of 3 to 7 inches are
expected in the St Lawrence Valley, 2 to 5 inches over much of the
remainder of northern NY and far northwestern VT, and 1 to 4 inches
for much of VT. Can`t rule out a glaze of ice just about anywhere,
but the most likely locations will be the St Lawrence Valley and
south central VT, and it is these locations that are included in the
Winter Weather Advisory. It should be noted that even in places that
warm enough to see plain rain, sharply colder temperatures by
evening may allow for icy conditions as wet roads freeze.

To go with all this will be the gusty winds, due to the
aforementioned 850 mb jet. Gusts of 30 to 40 mph will be possible
along the western slopes of the western slopes of the Adirondacks
and Greens due to downsloping of these winds, and can`t totally rule
out some gusts approaching 50 mph in the northern Greens. Otherwise,
gusts of 25 to 35 mph are expected elsewhere through the early-mid
morning hours Thursday. There will be a brief lull early in the
afternoon, then as winds turn to the west/northwest and colder air
spreads in, better mixing will result in gusts around 40 mph, first
in northern NY, then spreading toward the eastern sides of the
central/southern Greens.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
As of 422 AM EST Wednesday...Low pressure tracking along the St.
Lawrence Valley will exit the region Thursday, with widespread
precipitation coming to an end and a few light upslope showers
lingering across the higher terrain. Additional snowfall
accumulations will be minimal, generally a light dusting to an inch
across the Adirondacks and northern Greens. Colder air, especially
compared to earlier in the day, will continue to filter into the
region Thursday night, with overnight lows in the single digits and
teens. Strong and gusty winds will continue to linger Thursday night
as the system, and low level jet, exit the region. A brief lull in
our extremely active weather pattern is expected for Friday as the
region remains in between systems. Some lake effect snow off Lake
Ontario will be likely, however it looks to remain to the south of
the forecast area, with seasonably cool weather expected for much of
the region on Friday. High temperatures will only climb into the
teens to low 20s, with overnight lows in the single digits above and
below zero.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
As of 422 AM EST Wednesday...Heading into the weekend, our next
system will likely arrive Saturday as low pressure tracks
northeastward out of the Ohio Valley, although ECMWF and GEFS
ensemble members continue to show a large range of possible low
tracks. A widespread and long-duration event is likely, with NBM
probabilities of snowfall amounts exceeding 6 inches remain between
50-70% across the forecast area. Although there is large agreement
that precipitation will happen this weekend, there is still a lot of
uncertainty with this system, especially in regards to precipitation
type and amounts, especially when looking at some of the
deterministic global models. Although the forecast continues to
show mostly snow for now, trends will need to be monitored for the
potential for more mixed precipitation as we get closer. Beyond this
system, broad cyclonic flow will continue to bring some chances for
upslope showers,with high pressure building in mid-week.

Temperatures throughout this period are seasonable, with highs in
the 20s and lower 30s and overnight lows in the teens and single
digits. Heading into next week, temperatures look to trend much
colder, with highs in the teens and frigid overnight lows.

&&

.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
Through 12Z Thursday...Low cloud deck has lead to localized IFR
at KRUT and MVFR at KBTV, but these are not expected to persist
beyond 14z. Thereafter, expect VFR conditions with mainly
mid/high clouds at all terminals. Ceilings will gradually lower
after 21z as low pressure approaches from the southwest, with
MVFR expected at most sites by the end of the TAF period. Snow
will move in after 00z Thu, lowering visibility to 2-5SM from
west to east after 02z. Snow will mix with ice pellets toward
the end of the TAF period, mainly at KSLK/KBTV/KRUT. Light and
variable winds will trend toward east/southeast after 21z Wed,
though remaining 5-8 kt until noticeable increasing after 00z
Thu. An incoming 65+ kt jet will result in gusts of 25 to 30 kt
and areas of LLWS and turbulence after 06z Thu.

Outlook...

Thursday: Mainly MVFR, with local IFR possible. Windy with gusts
to 35 kt. Definite SN, Definite PL, Definite FZRA, Chance RA.
Thursday Night: VFR. Windy with gusts to 30 kt. Slight chance
SHSN.
Friday: VFR. NO SIG WX.
Friday Night: VFR. NO SIG WX.
Saturday: VFR. Likely SN.
Saturday Night: MVFR and IFR. Likely SN.
Sunday: Mainly MVFR, with local IFR possible. Definite SN.

&&

.EQUIPMENT...
The Mount Ascutney NOAA Weather Radio transmitter, serving
portions of eastern Vermont, is currently out of service. The
earliest date of restoration is Tuesday, February 18th. We
apologize for any inconvenience.

&&

.BTV WATCHES/WARNINGS/ADVISORIES...
VT...Winter Weather Advisory from 7 PM this evening to 7 PM EST
     Thursday for VTZ010-011-018>021.
NY...Winter Weather Advisory from 7 PM this evening to 7 PM EST
     Thursday for NYZ026>031-034-035-087.

&&

$$
SYNOPSIS...Hastings
NEAR TERM...Hastings/Kutikoff
SHORT TERM...Kremer
LONG TERM...Kremer
AVIATION...Hastings
EQUIPMENT...WFO BTV