716
FXUS63 KUNR 221125
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
525 AM MDT Sat Jun 22 2024

.KEY MESSAGES...

- Warm with limited thunderstorm activity for the fist half of the
  coming week.

&&

.DISCUSSION...(Today Through Friday)
Issued at 133 AM MDT Sat Jun 22 2024

Current surface map places weak high across the Dakotas with
trough moving through eastern Montana. Water vapor shows mid level
trough from eastern Montana into the Nebraska Panhandle. Showers
and thunderstorms are located across south central South Dakota
into northwestern South Dakota/southeastern Montana.
Shower/thunderstorm activity will continue to move eastward this
morning with most of the activity east of the forecast area this
morning. The rest of the day will feature weak subsidence with
building mid/upper level heights. Soundings maintain sufficient
buoyancy for thunderstorms this afternoon. However cap and lack
of forcing should limit thunderstorm development to the Black
Hills. Shear marginally strong enough this afternoon that if
storms do develop, there will be some threat of hail.

Flat upper ridge sets up across the area Sunday with low level
thermal ridge surging northward and will be the first of several
days with highs around or above 90F. Ridge gets knocked down
Monday with strong shortwave tracking across southern Canada.
Monday should be the warmest day with highs in the mid/upper 90s.
Weak impulse and steep mid level lapse rates may bring a few
thunderstorms Monday night. Upper trough moves into Pacific
Northwest mid-week then tracks through the Northern Plains
Thursday/Friday bringing an uptick in thunderstorm activity for
the last half of the week.

&&

.AVIATION...(For the 12Z TAFS Through 12Z Sunday Morning)
Issued At 517 AM MDT Sat Jun 22 2024

Widespread MVFR CIGS in scattered showers and thunderstorms, along
with areas of IFR CONDS due to low stratus and fog, currently
located from northwestern to south central South Dakota, will
improve to VFR by 17Z this morning, as the CIGS improve and the
precipitation moves off to the east. VFR conditions will then
prevail through the rest of the forecast period. There is a slight
chance of showers and thunderstorms this afternoon, over and near
the Black Hills and northwestern South Dakota.

&&

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

$$

DISCUSSION/KEY MESSAGES...7
AVIATION...10