Summerset, South Dakota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

258
FXUS63 KUNR 092001
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
201 PM MDT Mon Jun 9 2025

.KEY MESSAGES...

-Unsettled the remainder of this week with near daily chances for
 showers and storms, with confidence in precip chances less clear
 by this weekend

-Seasonal temps this week, coolest Thursday

-Smoke/haze possible through the period

&&

.DISCUSSION...(This Evening Through Monday)
Issued at 159 PM MDT Mon Jun 9 2025

Unsettled westerly flow will develop this week as a series of
impulses eject out of the NE Pac upper low. Upper low in the Great
Lakes will shift east as the region transitions from northwest to
westerly upper level flow. Clear skies in place today with dry NW
flow continuing to support smoke/haze into the region from
Canadian wildfires. Upper ridge will shift east and support much
warmer conds Tues as many locations will see highs in the 90s.
Ridge topping impulse will then move into the region tomorrow,
supporting increasing chances for showers and storms in the late
afternoon northeast WY, with activity shifting east Tues night as
a lobe of Pac moisture advects over the region. Not expecting any
severe weather, but a few stronger cells will be possible. Things
will shift east Wed with a period of weak subsidence over much of
the FA Wed until the next wave approaches. Hence, most places will
likely be dry Wed over western SD as the frontal boundary stalls
over the region. However, another impulse will move into the area
late Wednesday afternoon and evening supporting convection over
northeast WY by late afternoon or early evening. Enough CAPE will
be in place to support a few strong to severe storms there,
however, bulk shear will be lacking, offering mainly a wind threat
with cells. Convection will again shift east overnight with
showers and storm chances spreading into western SD. Frontal
boundary will then shift back southwest Thur, with much cooler
conds expected most places, esp over NW SD where temps will
struggle out of the 60s for highs. Things will most likely dry out
Thur as the departing wave shifts east, with perhaps some
lingering precip chances in eastern areas, as well as the Black
Hills where enough diurnal instability may be in place for a few
isolated afternoon showers. Beyond Thursday, forecast confidence
drops off as precip chances will hinge on the location of the
stalled front, wave timing, and moisture recovery, with the best
chances for convection INVOF of the BH this coming weekend as
temps recover and warm back up.

&&

.AVIATION...(For the 18Z TAFS Through 18Z Tuesday)
Issued At 1135 AM MDT Mon Jun 9 2025

VFR conditions expected through the TAF period. Gusty northwest
winds over the western SD plains will diminish late this afternoon
into the early evening.

&&

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

$$

DISCUSSION/KEY MESSAGES...JC
AVIATION...Dye