475
FXUS61 KBTV 181124
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
724 AM EDT Sat Apr 18 2026
.WHAT HAS CHANGED...
As of 303 AM EDT Saturday...
A Wind Advisory has been issued for Franklin and Clinton
Counties in New York from 5 PM Today to Midnight Tonight for
gusts up to 40 to 50 MPH. Elsewhere gusts were increased to 30
to 40 MPH.
&&
.KEY MESSAGES...
As of 303 AM EDT Saturday...
1. Gusty winds associated with an approaching frontal system
are expected today with the strongest gusts across northern New
York and near the International Border.
2. A cold front will bring widespread rain showers tonight with
much cooler temperatures for Sunday into early next week. Rain
will turn to snow over higher elevations, with some mountain
accumulations expected.
3. Spotty, light precipitation is possible on Tuesday, then
temperatures gradually increase into late next week.
&&
.DISCUSSION...
As of 303 AM EDT Saturday...
KEY MESSAGE 1: A Wind Advisory is in effect for Franklin and
Clinton Counties in northern New York from 5 PM today to
midnight tonight for wind gusts between 40 to 50 MPH. The
strongest gusts will be located along the US Route 11 corridor
from Moira, NY to Ellenburg Depot, New York around 8 PM tonight.
A few power outages and downed tree limbs may result.
Ahead of a strong cold front tonight, lapse rates will steepen
as large scale divergence leads to drying atmospheric profiles
areawide. Surface dewpoints will dry into the low to mid 40s
across Vermont with weak cold air damming behind a departing
area of high pressure, with dewpoints slightly higher across the
St. Lawrence Valley due to increasing southerly flow throughout
the day. Temperatures will also surge into the mid 60s to near
70 across Vermont, with low to mid 70s in northern New York
where better mixing and southerly flow will be located. These
increasing temperatures, coupled with surface drying and an
approaching 850 mb low level jet to 50 to 60 knots, will help
mix down gusty winds to the surface. Widespread gusts,
beginning to increase this morning into this afternoon, will
reach 30 to 40 MPH for most locations by mid to late this
afternoon, peaking around sunset. The strongest winds are
expected to be across the northern fringes of the Adirondacks
where enhancement from downsloping will lead to gusts up to 40
to 50 MPH, particularly along US 11 near Malone, NY. Channeled
flow in the northern Champlain Valley and St. Lawrence Valley
could lead to some isolated briefly higher gusts to 45 MPH, but
confidence is lower than portions of northern New York for
reaching Wind Advisory Criteria. Winds will subside after
midnight tonight as precipitation begins to overspread the
region.
KEY MESSAGE 2: A cold front will slide through the area late
this evening into tonight with widespread rain expected. The
front is expected to move into the St. Lawrence Valley between
7-9 PM, but as it moves east, it will weaken and become washed
out by tomorrow morning as it encounters drier air and blocked
flow. However, a secondary arctic cold front will provide
additional moisture and energy leading to continued
precipitation chances across northern New York and Vermont by
late Sunday. As the secondary front enters the region,
significantly colder air aloft will mix towards the surface with
temperatures plummeting below freezing into the 20s by Sunday
Night. The timing of this cold air is tricky as the dynamics
between the two cold front is not handled very well. It is
expected that temperatures will be non-diurnal Sunday with
temperatures falling throughout the day, but when the stronger
caa arrives will play a role in a precipitation changeover to
snow. Mountain summits will see a changeover to snow first
during the day Sunday, but the timing of the precipitation with
the strongest cold air varies between models. The HRRR and ECMWF
ensembles show a warmer system with more delayed cold air
arriving leading to rain in the valleys with tapering off
precipitation before the colder air arrives. The NAM3K has been
consistent, however, in co-locating the cold air arrival with
the backside of the precipitation which could lead to a period
of briefly heavy snow across the Champlain Valley. Current
expectations, and given the time of year, is for a mix of
rain/snow with perhaps some sleet mixed in, with little to no
valley snow accumulations, however, should the system amplify
more and become oriented north-south, slowing the system, some
snow may be favored in the deeper valleys. Winds will turn to
the northwest with breezy northwest flow, leading to wind chills
in the upper 20s to mid 30s. Regardless with precipitation and
colder temperatures, expected a raw, damp, and breezy end to the
weekend.
Temperatures will remain cold Monday into Monday Night with
strong radiational cooling and brisk northwest flow.
Temperatures will struggle to reach 40 degrees on Monday. Some
snow upslope snow showers under northwest flow may be possible
in the higher terrain, but accumulations will be minimal if at
all. Strong radiative cooling under clear skies Monday night
will lead to winter like temperatures as overnight lows fall
into the low to mid 20s, with some teens in the colder hollows
of the Adirondacks and Northeast Kingdom.
KEY MESSAGE 3: An axis of high pressure ridging will shift from
northern New York and Vermont into southern New England on Tuesday,
returning southerly to southwesterly flow to the region and helping
temperatures climb back towards typical springtime normals. Highs
Tuesday will still be below seasonal averages in the 40s and lower
50s, but it will be noticeably warmer than Monday with a little more
sunshine and the warming south wind. However, clouds will be on the
increase throughout the day ahead of our next shortwave that may
bring some spotty, light precipitation Tuesday afternoon through
early Wednesday morning. Precipitation type will be highly elevation
dependent, with snow showers possible in the mountains and rain
showers in the valleys as low temperatures vary across the 30s F.
Any snow accumulations would likely be restricted to the high
terrain and very minor. Wednesday through Thursday, high pressure
over Hudson Bay will remain in control, allowing daytime
temperatures to moderate into the upper 40s and 50s but remain below
seasonal normals as upper level troughing gyrates over the Canadian
maritimes, keeping flow northwesterly as our area is on the edge of
the cyclonic flow. Due to this northwesterly flow as well as
nighttime clearing under high pressure, lows look to remain near or
below normal in the upper 20s and 30s. Towards the end of the week,
models project a wave to ride along cyclonic flow into our area,
indicating the potential for precipitation. However, deterministic
guidance does not agree on timing/strength of this feature,
placement of surface features, nor source of moisture for precip, so
it is yet to be determined how exactly this plays out. Most likely
will be showery and seasonable to start the weekend, but no major
impacts anticipated.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
Through 12Z Sunday...Patchy dense fog and low clouds are expected to mix out this morning
over the next couple of hours. Then, gusty southerly and
southeasterly winds associated with an approaching frontal system
are expected today with the strongest gusts across northern New York
and near the international border. A cold front will bring
widespread rain showers tonight, and rain will turn to snow over
higher elevations. Widespread gusts, beginning to increase this
morning into this afternoon, will reach 25-35 knots for most
locations by around 14Z Saturday, peaking around sunset. The
strongest winds are expected to be across the northern fringes of
the Adirondacks where enhancement from downsloping will lead to
gusts up to 35 to 45 knots. A Wind Advisory is in effect for
Franklin and Clinton counties, New York, from 21Z Saturday through
04Z Sunday for wind gusts 35-45 knots, mainly north of sites KSLK
and KPBG. Channeled flow in the northern Champlain and St. Lawrence
valleys could also lead to some isolated briefly higher gusts to 40
knots. Widespread LLWS is anticipated after 00Z Sunday as a strong
low level jet moves overhead.
Surface winds will then begin to decrease around 05Z-09Z Sunday
as rain showers arrive across northern New York and Vermont
from west to east. Ceilings will also be on the decrease
throughout the day today ahead of precipitation, lowering to
around or below 3000 feet above ground level around the same
time precipitation arrives, give or take a couple hours in
either direction. Visibilities with this rainfall will likely be
4+ miles, especially high at the onset of precip due to dry air
making it hard for rain to reach the surface initially.
Visibilities may lower in locations that changeover to snow,
including KSLK around 09Z Sunday or later. Winds will be
switching around to be out of the southwest for some locations
around 05Z-09Z, eventually turning out of the northwest at the
very end of or after the end of the 24 hour TAF period.
Similarly, IFR ceilings are possible at the tail end of the TAF
period (beyond 09Z Sunday), most likely at KSLK.
Outlook...
Sunday: MVFR/IFR conditions possible. Chance SHRA, Chance SHSN.
Sunday Night: VFR. Chance SHSN.
Monday: VFR. NO SIG WX.
Monday Night: VFR. NO SIG WX.
Tuesday: VFR. Slight chance SHRA.
Tuesday Night: Mainly VFR, with areas MVFR possible. Slight
chance SHRA, Slight chance SHSN.
Wednesday: Mainly MVFR, with local IFR possible. Slight chance
SHRA.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...Wind Advisory from 5 PM this afternoon to midnight EDT tonight
for NYZ027-028-030-031.
&&
$$
WHAT HAS CHANGED...Danzig
DISCUSSION...Storm/Danzig
AVIATION...Duell/Storm
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