Spearfish, South Dakota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

495
FXUS63 KUNR 250948
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
248 AM MST Thu Dec 25 2025

.KEY MESSAGES...

- Gusty southwest winds expected over northeastern Wyoming and the
  Black hills through this morning.

- Areas of fog over parts of northwestern SD this morning.

- Above normal temperatures continue the rest of the week before a
  cold front moves through Saturday night into Sunday.


&&

.DISCUSSION...(Today Through Wednesday)
Issued at 215 AM MST Thu Dec 25 2025

Current satellite and upper air models show upper ridge over the
northern and central plains this morning, with upper trough off
the west coast. Most recent surface analysis shows low over
southeastern MT, with boundary stretching through the Black Hills
into central Nebraska. Areas of fog and dense fog are ongoing for
parts of northwestern into central SD. Strong downslope winds have
developed over the northern foothills.

Surface low will shift eastward this morning and associated front
will lift up through the forecast area. Tight pressure gradient
will allow for some strong southwest winds through the morning, as
well as downsloping potential over the northern foothills. High
Wind Warning remains in effect for the northern foothills, while
the Wind Advisory remains in effect for the central foothills.
Some CAMs do point at possible light precipitation later this
morning into the afternoon near the boundary, however ensemble
probabilities are very low, have kept mention of PoPs out of the
forecast for now. Following the warm front, expect near-record to
record high temperatures for Christmas day. HREF probabilities of
MaxT > 65F range from 50-90% from Rapid City down into south
central SD.

The upper ridge will still affect the forecast area on Friday,
resulting in another warm day, but attention then turns to a
pattern change on Saturday. Ridge slides eastward as upper low
treks across southwestern Canada. Disturbance will trek across the
northern plains later Saturday into Sunday, ushering in colder
temperatures as well as some light precipitation chances.
Temperatures rebound again on Monday as upper ridge builds back
over the west coast into the Rockies, resulting in warmer and dry
conditions the remainder of the forecast period.


&&

.AVIATION...(For the 06Z TAFS Through 06Z Thursday Night)
Issued At 953 PM MST Wed Dec 24 2025

Gusty southwest winds will continue to strengthen across parts of
northeast Wyoming and the Black Hills and persist through
Thursday morning. Gusts in excess of 45 knots are possible at
times.

MVFR/IFR conditions in patchy dense fog will continue over
northwestern into south central SD. Fog will dissipate after 15z.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...Dense Fog Advisory until 8 AM MST this morning for SDZ002-013-
     014-032-078.
     High Wind Warning until 2 PM MST this afternoon for SDZ025.
     Wind Advisory until 2 PM MST this afternoon for SDZ026-072-074.
WY...High Wind Warning until 2 PM MST this afternoon for WYZ060.
&&

$$

DISCUSSION/KEY MESSAGES...Dye
AVIATION...Wong