509
FXUS63 KUNR 222018
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
118 PM MST Mon Dec 22 2025

.KEY MESSAGES...

- Windy, mainly dry, and unseasonably warm this week

&&

.DISCUSSION...(This Evening Through Monday)
Issued at 117 PM MST Mon Dec 22 2025

Most recent upper air analysis depicts near zonal, westerly flow
over the Northern Plains. Skies over the CWA are mostly clear save
for a thin layer of cirrus. Most recent sfc analysis depicts E-W
oriented frontal boundary draped across the CWA with gusty
westerly winds to the south of the front and northwest winds to
the north. Temperatures have climbed into the 50s to mid 60s over
much of northeastern WY and southwestern into south central SD.
Some spots in southwestern SD and south central SD have hit the 70
degree mark thanks to the downslope flow. Our office in Rapid
City briefly hit 68F, which breaks our daily record high (65 set
back in 2020). The winds have shifted to the north and
temperatures dropped to around 51F. Gusty winds have developed
over our Southern Foothills and Hermosa Foothills zones with a few
stations reporting gusts of 40+ in the past hour.

Marginally cooler on Tuesday behind our "cool" front before temps
rebound on Wednesday ahead of another weak, moisture starved
impulse cresting the upper level ridge. We could set more daily
records for high temperatures on Wednesday, Christmas Day, and
Friday as temperatures climb into the upper 50s to 60s. Safe to
say that we`re not expecting a white Christmas this year. Another
dry cool front moves through the afternoon of Christmas Day with
the main impact being breezy winds, increased cloudiness, and
maybe a few rain showers over the Northern Black Hills.

Deterministic guidance in better agreement of a stronger wave and
attendant front moving through early Saturday. Precip chances
aren`t looking great for most of the CWA, though the Black Hills
and northeastern WY may see some snow showers early Saturday
morning. Temperatures Saturday and Sunday will drop to more
"seasonable" levels with highs in the 30s to 40s.

&&

.AVIATION...(For the 18Z TAFS Through 18Z Tuesday)
Issued At 1034 AM MST Mon Dec 22 2025

VFR conditions are expected through the TAF period. Gusty west to
southwest winds will be common across portions of northeastern
Wyoming, the Black Hills, and southwestern South Dakota through
23Z today.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...Wind Advisory until 3 PM MST this afternoon for SDZ027-074.
WY...None.
&&

$$

DISCUSSION/KEY MESSAGES...Wong
AVIATION...15