312
FXUS63 KUNR 241105
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
405 AM MST Mon Nov 24 2025

.KEY MESSAGES...

- Strong cold front arrives late tonight along with light snow.
  Accumulations 1-3 inches in the northern Black Hills.

- High winds expected for western South Dakota Tuesday behind the
  front, where gusts up to 60 mph are possible.

- Cold and snowy Thanksgiving weekend.

&&

.DISCUSSION...(Today Through Sunday)
Issued at 201 AM MST Mon Nov 24 2025

A closed upper low is centered over eastern CO/western KS with a
surface low developing over SE CO/SW KS/OK Panhandle. Further
upstream, water vapor imagery shows upper level trough axis
pushing through BC and WA with vorticity maximum overspread
western MT. This wave will dive into the Northern Plains later
tonight with a strong cold front to arrive after 02-04z. As large-
scale lift overspreads the area and winds shift northwesterly,
light rain/snow is expected tonight through Tuesday. Any rain will
quickly change to all snow as colder air pushes in behind the
front. Snow accumulations will be light with less than an inch
across northwestern SD; 1-3" of snow is possible across the higher
elevations of the Wyoming and northern Black Hills through Tuesday
morning. Little to no accumulation expected elsewhere.

Strong winds will accompany the frontal passage Tuesday morning
through the afternoon hours. Strong cold air advection coupled
with steep lapse rates will result in mixing of higher momentum
air aloft, with gusts up to 60 mph possible in two waves: 1) with
the initial frontal passage and 2) after 12z when strongest winds
aloft overspread the area. The best chance of warning criteria
winds will extend from NW SD into the south-central Plains where a
High Wind Watch has been issued.

As the shortwave trough pivots east and deepens across the Upper
Midwest/Great Lakes, surface high pressure will settle over the
Northern Plains with below average temperatures and dry conditions
Wednesday through Thanksgiving.

Attention then turns to the next weather maker early Friday
through next weekend. Models continue to diverge regarding
synoptic evolution, timing, and precipitation chances. Regardless,
there remains high confidence that much colder air will filter
into the region next weekend along with near-daily chances of
light snow Friday through Sunday.

&&

.AVIATION...(For the 12Z TAFS Through 12Z Tuesday Morning)
Issued At 402 AM MST Mon Nov 24 2025

VFR conditions are expected through the afternoon hours today.
After 02-04z tonight, a cold front will push through bringing
MVFR/IFR conditions in rain/snow and low clouds to the area,
particularly NE WY and NW SD. Winds will shift northwesterly
behind the front with gusts 30-45 knots after 03-05z through
Tuesday afternoon.


&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...High Wind Watch from this evening through Tuesday afternoon for
     SDZ001-002-012>014-025-026-030>032-042>044-046-047-049-072-
     073-077-078.
WY...None.
&&

$$

DISCUSSION/KEY MESSAGES...SE
AVIATION...SE