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000
FXUS63 KUNR 282328
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
528 PM MDT Sun May 28 2023

.DISCUSSION...(This Evening Through Sunday)
Issued at 1231 PM MDT Sun May 28 2023

Water vapor shows western CONUS trof with eastern CONUS rex block,
with distinct short wave tracking north across the NE panhandle.
At the surface, trof covers the western Dakotas. Showers continue
to track north into northwest SD, with some convection beginning
to bubble in the northern Black Hills. Clouds remain mostly cloudy
with early afternoon temps in the 60s/70s.

MLCAPE early this afternoon is around 500J/kg with plenty of CIN
due to expansive mid/high clouds associated with the short wave.
As cloud cover gradually decreases from southwest to northeast
this afternoon, expect MLCAPE to rise to 1000-1500J/kg with
scattered thunderstorms developing first in the Black Hills then
onto the plains. Effective bulk shear is quite weak today at 20kts
or less, so severe threat will be quite limited and should mainly
be confined to western SD along and east of the surface trof.
Activity will gradually spread east this evening and end
overnight.

A northern stream short wave moves through Monday as western CONUS
trof splits. Additional storms expected, with better chance for
strong/severe storms along and east of persistent trof over
western SD. However, shear will once again be relatively weak so
widespread severe storms unlikely.

Unsettled conditions will persist through the week and next
weekend with daily chances for storms. Southwest flow aloft will
strengthen mid to late week, with better chances for more
widespread storms late in the week as robust upper low/trof ejects
northeast from the Desert SW. Temps will generally be a few
degrees above average most days.

&&

.AVIATION...(For the 00Z TAFS Through 00Z Monday Evening)
Issued At 527 PM MDT Sun May 28 2023

Scattered showers and thunderstorms will bring IFR conditions with
the heavier rain. Otherwise, VFR conditions expected through the
period.

&&

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

$$

DISCUSSION...Johnson
AVIATION...7