656
FXUS63 KUNR 301901
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
101 PM MDT Thu May 30 2024

.KEY MESSAGES...

- Unsettled at times through the weekend into early next week,
  with best chance for some severe storms on Sunday.

- Warmer weather by the end of the weekend, with a drier pattern
  developing by mid/late next week.

&&

.DISCUSSION...(This Evening Through Thursday)
Issued at 1232 PM MDT Thu May 30 2024

Water vapor shows upper trof over the Northern Rockies beginning
to shift into the Northern Plains. At the surface, associated cold
front has crossed through all but far southeastern Tripp county,
with breezy northwest winds and early afternoon temps mainly in
the 60s.

A few showers/storms will remain possible for the next couple
hours across eastern Tripp counties, but best severe threat will
remain south/east of our area. Later tonight, right rear quad of
jet streak rounding the upper trof will move overhead and provide
the necessary lift for a good chance of showers and a few non-
severe storms to develop in our southwest zones. This activity
will then spread northeast across the area Friday morning, ending
from southwest to northeast during the afternoon. Lack of
CAPE/shear should keep the better severe threat to our south/east.
Highs Friday in the 60s to lower 70s.

Upper trof shifts quickly east Friday night with zonal flow on
Saturday. Return flow will ensue with surface ridge shifting from
the eastern Dakotas into the Midwest. Could be some storms that
develop across our southern zones with the arrival of the next
disturbance in the zonal flow, and given the increasing CAPE with
the return flow there could be a few stronger storms.

A better severe threat is possible across our area on Sunday as
warm front lifts north ahead of an approaching cold front, with
the cold front expected to move in during the afternoon.

Unsettled weather is likely to continue through early next week,
but a ridge building to our west could signal a drier and warmer
pattern as next week progresses.

&&

.AVIATION...(For the 18Z TAFS Through 18Z Friday)for this weekend and beyond,
 with a drier pattern likely developing for much of next week.
Issued At 1031 AM MDT Thu May 30 2024

VFR conditions will continue through this evening. After midnight
or so, showers and isolated thunderstorms will develop across
portions of northeastern WY and western SD, resulting in some MVFR
conditions through Friday morning.

&&

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

$$

DISCUSSION/KEY MESSAGES...Johnson
AVIATION...Pojorlie