165
FXUS63 KUNR 161836
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
1236 PM MDT Thu May 16 2024

.KEY MESSAGES...

- Unsettle pattern continues through the period.

- Very warm Friday. Late day thunderstorms with cold front could
  bring some locally strong wind gusts.

&&

.DISCUSSION...(This Evening Through Thursday)
Issued at 1220 PM MDT Thu May 16 2024

Water vapor shows upper low over southern BC with flat ridge
extending from the Pac NW through the Northern Plains. At the
surface, weak trof covers the western Dakotas. Early afternoon
temps are in the 60s/70s with congested cu over the Black Hills.

A weak short wave in the westerly flow aloft will bring a few
light showers/storms from the Black Hills into northwest SD this
afternoon and evening, but moisture/instability is fairly
insignificant.

Low level thermal ridge peaks on Friday for very warm temps, close
to 90 in some areas east of the Black Hills. More significant
short wave crosses the Northern Rockies in the afternoon and
Northern Plains overnight, driving a Pacific cold front through
the area. Scattered thunderstorms forming along the front,
especially in and north of the Black Hills, could pose a wind a
threat given the expected inverted-v soundings. Post frontal winds
should be near advisory for a period of time by evening and
overnight, especially across northwest SD.

Drier/cooler/breezy conditions expected Saturday in wake of Friday
night`s cold front. Next short wave crosses the Northern Rockies
Sunday, with low level thermal ridge peaking again across the area
for another warm day. Associated cold front moves through late in
the day for another chance for showers/storms.

Mean trof across the northwest and north-central CONUS through
next week will keep conditions unsettled with cold fronts moving
through nearly every day.

&&

.AVIATION...(For the 18Z TAFS Through 18Z Friday)
Issued At 1122 AM MDT Thu May 16 2024

Isolated showers will be possible this afternoon and evening
across portions of the western SD plains. Other than any brief
MVFR conditions near any precipitation, VFR conditions are
expected through the TAF period.

&&

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

$$

DISCUSSION/KEY MESSAGES...Johnson
AVIATION...Dye