Red Shirt South Dakota Weather Forecast Discussion

202
FXUS63 KUNR 110822
AFDUNR
Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
222 AM MDT Sat Oct 11 2025
.KEY MESSAGES...
- Mild today with gusty southeasterly winds and small chances for
  precipitation
- Enhanced downslope winds for the eastern slopes of the Black
  Hills overnight tonight
- Upper level trough and cold front Sunday will bring very windy
  northwesterly winds, colder weather, and PoPs in the northwest
- Freezing temperatures possible Monday morning
&&
.DISCUSSION...(Today Through Friday)
Issued at 219 AM MDT Sat Oct 11 2025
08z surface analysis had high over the upper Midwest and lee
trough from central MT into eastern CO. Decent pressure gradient
between the two supporting gusty southeast winds at times where
40-50kt low-level jet (per KUDX WSR-88D VWP) is able to affect
the surface winds. Low-level jet supplying modest theta-e
advection over central SD ahead of a weak shortwave (noted on
water vapour loop over the central Plains). Result is some
sprinkles/spotty showers east of the Black Hills. Widening our
view, we see upper ridge to our east and upper low/trough over the
northwest CONUS. Distinct shortwave over the four corners area
heading out way for today.
Today/this evening, thermal ridge peaks over the CWA under
sustained southwesterly flow aloft. 700mb temperatures reach ~8C,
which supports highs in the 70s/lower 80s per guidance. Tight
pressure gradient continues with 30-40mph gusts (chance of >45mph
gusts per HREF 45mph gusts per HREF ~50%). Cold front will kill the
downslope enhancement Sunday morning, but 2-4mb/3hr pressure rises
behind it will stir up gusty westerly winds over the northwestern
SD plains in the morning. Then, as shortwave rapidly moves
northeast into Canada, a secondary cold front moves through with
moderate cold air advection and well-defined subsidence drying up
PoPs. 30-40kt 800mb winds/well-mixed boundary layer will lead to
very windy northwest winds in the afternoon/early evening.
Bufkit/MOS guidance portrays high-end Wind Advisory
event/possible low-end warning event. NBM/HREF probabilistic
guidance indicates chance of >55mph gusts 

NWS UNR Office Area Forecast Discussion