022
FXUS63 KUNR 241818
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
1218 PM MDT Sat Oct 24 2026

.KEY MESSAGES...

- Light rain will move into the area overnight tonight and
  continue through Sunday

- A trace to an inch of snow possible over northwestern SD and the
  Black Hills on Monday.

- Warming trend commences Tuesday through the end of the week with
  highs in the 50s to 60s

&&

.DISCUSSION...(This Evening Through Saturday)
Issued at 1217 PM MDT Sat Oct 24 2026

Sfc analysis shows strong cold front has pushed to the east of
the forecast area with northwest winds steadily diminishing
through this morning. Upper level analysis and water vapor show a
closed upper low over AZ with convection moving through northern
NM. Meanwhile to the north of the Dakotas, an upper low spins over
central SK. Expect clearing skies through this afternoon thanks
to height rises and drier air moving into the area. Highs this
afternoon will be more seasonable, ranging from the upper 40s to
mid 50s.

Our next round of precip will move into the area Sunday afternoon
as the upper low over the Desert Southwest begins to slowly move
into the region. Area of modest QG forcing along with near
saturated moisture profiles from around H850 to H700 will support
precip in the form of rain beginning overnight tonight into early
Sunday morning across south central SD and moving northward
through the day as the upper low drifts northeast. Rain will
continue through the overnight hours Sunday with the Black Hills
getting cold enough for some snow to mix in.

The upper low continues its trek across the region through Monday
with chances for precip continuing through the day. As colder air
associated with the core of the upper low moves into the area,
snow may begin to mix in with the rain, especially over
northwestern SD and in and around the Black Hills. We may see a
transition to all snow over the Black Hills and far northwestern
SD late in the afternoon to evening. In terms of accumulations,
there`s still a little uncertainty as it will depend on when the
colder air moves in at the mid levels and the exact track of the
low. Even so, any accumulations are expected to be minor with some
areas over the northwestern SD plains and Black Hills potentially
seeing a dusting up to an inch of slushy accumulation. Any
accumulations should be gone by Tuesday as warmer air moves back
into the region.

Upper level shortwave and attendant moisture starved front will
move in from the PNW later on Tuesday. Could see some light rain
showers across far northeastern WY into northwestern SD with this
system with the only other impacts expected being breezy southwest
winds across the western SD plains and portions of northeastern
WY late Tuesday afternoon. Otherwise, upper level west-
southwesterly flow will keep temperatures seasonably mild after
Tuesday with dry weather expected through the late week.

&&

.AVIATION...(For the 18Z TAFS Through 18Z Sunday)
Issued At 1127 AM MDT Sat Oct 24 2026

The strong northwest winds across the region will continue to
decrease today.

VFR conditions are expected for the rest of the day into tonight.

Late in this forecast period into the next, chances of showers
will begin to increase from south to north over South Dakota
before spreading northwestward into Wyoming. MVFR to IFR is
likely.

&&

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

$$

DISCUSSION...Wong
AVIATION...GS