703
FXUS63 KUNR 152001
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
101 PM MST Sat Nov 15 2025

.KEY MESSAGES...

- Mild Sunday, then cooler with a chance of precipitation later
  Sunday night into Monday
- Seasonally cool and unsettled next week

&&

.DISCUSSION...(This Evening Through Saturday)
Issued at 1259 PM MST Sat Nov 15 2025

19z surface analysis has cool front west/south of the CWA with
weak trough from central MT into southeast SD, which is on the
back side of surface high over the eastern Dakotas. Weak return
flow/lift north of surface trough enough to support a few
sprinkles/lower clouds this afternoon over far northwestern SD.
Have added low PoPs to account. Water vapour matinee had upper low
off the CA coast with ridge into the Rockies and northwest flow
aloft over the CWA. CA upper low the main short term forecast
concern.

Tonight/Sunday, upper low ejects toward NV/UT in response to jet
streak/upper low diving south along the western CONUS. Shortwave
ridge builds over the CWA with neutral temperature advection.
Temperatures will be near guidance, making for a nice day Sunday
albeit with increasing mid/high clouds late.

Sunday night/Monday, compact upper low moves into the northern
Plains as it weakens and opens up over the upper Midwest. Moisture
return questionable, but QG-forcing/band of frontogenesis ahead
of the low should be sufficient for saturation and light QPF
(50-80% chance >0.01", 30-60% chance >0.10") later Sunday
night/Monday. Wet bulb zero heights marginal for snow even for the
highest elevations of the Black Hills with little/no accumulation
expected. Backwash precipitation may linger into Monday night.
Temperatures will be near guidance.

Tuesday through Thursday, split upper trough slowly moves into
the northern Plains with disturbances ahead of it under southwest
flow aloft. PoPs warranted (especially over the Black Hills) as
temperatures settle around climatological normals. For the end of
the forecast period, confidence is low given convoluted upper air
pattern and increasing probabilistic temperature spreads.

&&

.AVIATION...(For the 18Z TAFS Through 18Z Sunday)
Issued At 1026 AM MST Sat Nov 15 2025

VFR conditions will persist at the terminal sites through the
valid forecast period. Some MVFR cigs will be found across
northwest SD through 16/00Z before dissipating.

&&

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

$$

DISCUSSION/KEY MESSAGES...Helgeson
AVIATION...Hintz