527
FXUS63 KUNR 171126
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
526 AM MDT Fri Oct 17 2025

.KEY MESSAGES...

- Clearing skies and mild temperatures today

- Fast-moving system tonight/Saturday to bring showers and gusty
  northwest winds

- Warm weather briefly returns for Sunday, then blustery and
  somewhat unsettled on Monday

&&

.DISCUSSION...(Today Through Thursday)
Issued at 259 AM MDT Fri Oct 17 2025

Water vapor imagery shows the storm system lifting NE across ND at
this time. A weak wave is crossing far SE MT and rotating into the
CWA, bringing light radar rain across NW SD into the northern Black
Hills. Precip may be falling as snowflakes across the higher Black
Hills, though no accumulation is expected. Early morning fog is
shallow enough to dissipate early this morning. Midlevel subsidence
will return this morning on the backside of the upper wave as it
swings into the central Dakotas, clearing skies out across the CWA
and bringing a quiet rest of the day. Temperatures will reach the
upper 50s to upper 60s. Broad cyclonic flow persists across the
northern Rockies/Plains as the next system dives down the backside
of the trough. This clipper system will quickly push into the
northern Plains Friday night. Latest trends show the vort max a tad
farther south into eastern WY through western Neb, but still
expecting precip with this system along with brief, strong cold air
advection in the lower and mid levels. Steep lapse rates will
support shower development behind the cold front, mainly through the
Saturday morning hours. Not much QPF is expected with this...and
snow accumulations across the higher Black Hills will be minimal.
Decent pressure rises and ~40kt 700 mb winds transferring down to
the surface will have the potential of bringing perhaps low end
advisory winds to portions of the western SD plains. Highs will be
in the mid 40s to mid 50s. Upper ridging will build across the
region Saturday night and Sunday. Southwesterly flow/warm air
advection will bring a thermal ridge across the northern Plains
on Sunday, with highs reaching the 60s to mid 70s. The next system
then moves in from the northwest Sunday night into Monday. Model
are showing a strong cold front crossing the region Sunday
evening, with gusty winds persisting through Monday. This will be
our next shot for wind- related headlines, though the strongest
winds may be just behind the frontal passage itself. Still much
uncertainty with this. Not much QPF is expected across the CWA
with this system.

&&

.AVIATION...(For the 12Z TAFS Through 12Z Saturday Morning)
Issued At 525 AM MDT Fri Oct 17 2025

The back edge of the departing storm system is bringing lingering
showers across northwest SD into the northern Black Hills area.
The precip/low CIGS will clear out by 15z. VFR conditions are then
expected for the rest of the day and this evening, with breezy NW
winds across NW SD. A system will quickly push through the region late
tonight into Saturday, bringing gusty NW winds behind the front
and scattered showers. Gusts to 40 kt or more are possible. While
MVFR conditions are possible in the heaviest showers, VFR
conditions are still generally expected.

&&

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

$$

DISCUSSION/KEY MESSAGES...13
AVIATION...13