252
FXUS63 KUNR 160740
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
140 AM MDT Mon Jun 16 2025

.KEY MESSAGES...

-Severe storms possible today and Tuesday.

-Mostly dry and much warmer conditions for the second half of the
week.

&&

.DISCUSSION...(Today Through Sunday)
Issued at 137 AM MDT Mon Jun 16 2025


At 0730Z severe storms continue across northwestern South Dakota,
with the frontal boundary currently extending from Lemmon South
Dakota down to Weston Wyoming. Damaging winds will continue for
the next hours across northwestern South Dakota as additional
showers and thunderstorms develop along the cold front.

For today, another round of severe storms are expected late this
afternoon and evening. Expect storms to develop over eastern Wyoming
and southeastern Montana and move eastward through the evening and
overnight hours. Steep lapse rates and shear of 30-40 kts will once
again create the potential for large hail and strong wind gusts. The
main upper trough approaches the area Monday night, swinging through
the CWA Tuesday and Tuesday night. This will lead to scattered to
numerous showers and thunderstorms along with some cooler
temperatures. Showers and thunderstorms will end on Wednesday, with
some cooler air lingering as the upper ridge to the west begins to
build. Increasing heights return as the ridge axis moves into the
Intermountain West. This will bring drier conditions and a
return to warmer temperatures.

&&

.AVIATION...(For the 06Z TAFS Through 06Z Monday Night)
Issued At 1117 PM MDT Sun Jun 15 2025

Strong thunderstorms across central South Dakota will continue
eastward over the next two hours. A second area of thunderstorms
will affect northwest South Dakota over the next few hours. Both
areas of storms will produce strong, variable winds and hail.
Some short term models show patchy low clouds/fog across portions
of northeast WY through the Black Hills overnight. Otherwise, VFR
conditions are expected tonight through Monday morning. The next
round of storms will cross northeast WY in the late afternoon and
western SD through the evening hours.

&&

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

$$

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