385
FXUS63 KUNR 010107
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
707 PM MDT Wed Sep 30 2026

.KEY MESSAGES...

- Near or slightly above normal through the forecast period.

- Mostly dry conditions expected the remainder of the week.

&&

.DISCUSSION...(This Evening Through Wednesday)
Issued at 227 PM MDT Wed Sep 30 2026

Current Water Vapor and upper air models show near zonal flow
aloft, with an upper low located over the four corners region.
20Z surface analysis shows high pressure centered over Wyoming
this afternoon Satellite has some mid and high clouds reaching
into southwest and south central SD. Temperatures sit in the upper
60s and 70s, with generally light winds out of the northwest.
Little change to the overall pattern is expected through the
week, with near-zonal to northwest flow aloft hanging around.
Mostly dry conditions are expected as well. A cold front is
expected Thursday, dropping temperatures 15-20 degrees from today.
Limited moisture with this disturbance, but some light
precipitation will be possible Thursday into Thursday night.
Temperatures then warm up a bit for the first half of the weekend
before another boundary cools the region down again on Sunday.
Once again, with limited moisture advection, expect little to no
precipitation over the weekend. Early next week the upper ridge
builds over the western CONUS, prompting a rise in temperatures to
the 70s and low 80s for much of next week.

&&

.AVIATION...(For the 00Z TAFS Through 00Z Thursday Evening)
Issued At 707 PM MDT Wed Sep 30 2026

A frontal system will move through overnight bringing higher
winds, gusts and increased cloud cover. Overnight increasing low
level clouds below 3000ft in the Black Hills and NE WY could drop
conditions into MVFR/IFR and continue through the day Thursday.
Winds will decrease Thursday morning following the passage of the
system.

&&

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

$$

DISCUSSION...Dye
AVIATION...Ivory