847
FXUS63 KUNR 091924
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
124 PM MDT Thu May 9 2024

.KEY MESSAGES...

- Showers/isolated storms gradually ending tonight into Friday

- Warmer temperatures expected through early next week

- Dry for much of the weekend, then chances of showers/storms return
late Sunday, continuing into the middle of next week

&&

.DISCUSSION...(This Evening Through Thursday)
Issued at 122 PM MDT Thu May 9 2024

Upper-level analysis shows an elongated trough
stretching from the Great Lakes to the Four Corners, forming a
separate low as it begins to split. Clearing across the northern CWA
has allowed for some weak buoyancy to develop, and scattered showers
have increased early this afternoon. With high pressure moving in
from the north, surface winds are northerly 10-20 mph. Temperatures
are warming into the 50s and 60s.

A few lingering showers will be possible across the southwestern CWA
tonight into Friday. Additionally, moist air and light winds may
allow for some patchy fog across northeastern WY and the Black Hills
late tonight into early Friday.

The upper ridge will begin to dominate our weather pattern through
the weekend, while the cut-off low lingers over the southwestern
CONUS for a few days. Ensembles are in good agreement on warming
temps through the weekend and into early next week, although
temperature spreads increase Mon/Tues. Saturday will be dry, but
chances for showers/storms return Sunday afternoon as the Four
Corners low finally traverses the central plains. With low
CAPE/shear on Sunday, severe threat looks low.

On Monday, a shortwave trough will swing into the northern plains
from Canada, bringing another round of showers/storms. WAA ahead of
this trough could allow for increased instability/buoyancy, and with
slightly better shear, would not rule out a strong to severe storm
Monday afternoon/evening. Deterministic models show the trough
lingering over the central US through the middle of next week,
resulting in more showers/storms and cooler temperatures.

&&

.AVIATION...(For the 18Z TAFS Through 18Z Friday)
Issued At 1140 AM MDT Thu May 9 2024

Isolated to scattered rain showers will persist into the evening
hours today before tapering off after 00z. These showers will
bring MVFR conditions over northeastern WY, the Black Hills, and
far western SD. Conditions will slowly improve throughout the day,
and then VFR conditions should take hold for most places this
evening.

&&

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

$$

DISCUSSION/KEY MESSAGES...Pojorlie
AVIATION...Dye