936
FXUS63 KUNR 222257
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
357 PM MST Sat Nov 22 2025

.KEY MESSAGES...

- Mild and dry weekend.

- Pattern change by Thanksgiving Day, colder with rain/snow
  possible

- Staying cold with better chances for snow next weekend.

&&

.DISCUSSION...(This Afternoon Through Friday)
Issued at 1139 AM MST Sat Nov 22 2025

We are still tracking a shortwave embedded within the northwest
flow aloft to push into western ND and the northwestern corner of
SD later this afternoon. This will push a weak surface trough
through the western SD later this afternoon. The main weather
impact will be the increase of the surface winds. We can expect
winds to gust from the northwest between 20-30 mph later this
afternoon before diminishing this evening. Otherwise increasing
high level clouds will continue to advect into the region as the
day progresses putting a cap on the amount of heating we can
expect this afternoon. Expect a similar day tomorrow with
continued dry and mild conditions expected.

Heading into next week, long range and now short range models
continue to show that large closed low that is currently spinning
across the Desert southwest will move into the Central Plains that
could clip our border counties with some light rain showers. The
biggest weather maker will be a trough diving south into northern
Montana late Monday night. Models are in decent agreement with
this system pushing a strong cold front through the region late
Monday night into Tuesday morning ushering some much colder air
for most of western SD and eastern WY. Additionally models have
now closed this low over the upper Mississippi River valley to our
east and brings a strong area of high pressure into western
Montana. At this time the net pressure differences between this
two systems is 34mb and models and now show what looks like a
stinger jet feature developing between to these two areas and
placed directly over western SD. In response confidence has
increased slightly for the potential for some strong northwesterly
winds to develop across on Tuesday. Current forecast already has
wind gusts approaching 55 mph, so this trend will need to be
watched for the possibility of some Wind Highlights.

Looking ahead toward the Thanksgiving holiday and following
weekend, ensembles and deterministic models continue to be in
decent agreement of a longer term pattern change as a deep, long
wave trough moves into the area that will bring some of the
coldest maximum temperatures of the season so far and daily
chances for some snow to fall across a large portion of the
forecast area. This is still some five days out so trends will
continued to be monitored for where the greatest snow could fall
but overall confidence is high for a colder and wetter pattern
shift.

&&

.AVIATION...(For the 00Z TAFS Through 00Z Sunday Evening)
Issued At 357 PM MST Sat Nov 22 2025

VFR conditions are expected through the TAF period.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...None.
WY...None.
&&

$$

DISCUSSION/KEY MESSAGES...Woodward
AVIATION...Wong