074
FXUS63 KUNR 191112
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
512 AM MDT Sat Apr 19 2025

.KEY MESSAGES...

- Warmer and drier through this weekend with elevated fire weather
  conditions likely

- Active pattern will bring occasional light precipitation
  chances through next week

&&

.DISCUSSION...(Today Through Friday)
Issued at 152 AM MDT Sat Apr 19 2025

Positively tilted trof axis extends from the Northern Plains into
the Four Corners region with a cut-off upper low spinning over
northern AZ. Water vapor imagery depicts dry air pushing into the
region, resulting in mostly clear skies over the forecast area.
Sfc charts depict elongated region of high pressure stretching
from the Hudson Bay into the Northern and Central Plains. The
cooler airmass associated with this high pressure system has
settled across the region, temperatures across the CWA have
dropped into the 20s to low 30s. Some spots in the Black Hills are
dipping into the teens.

The high pressure will slide to the southeast today with
southerly return flow and WAA in its wake. Thermal ridge will push
into the Northern Plains and bring warmer temperatures back to
the CWA. Temperatures this afternoon will be in the upper 50s to
low 60s. South to southwesterly low level flow will continue
through Sunday and Monday, facilitating a warming trend,
especially across the western SD plains. Temperatures by Monday
afternoon will reach into the low to mid 70s. The warm and dry
conditions (RHs in the teens to 20s) and southwest winds of 10 to
15 mph, gusting up to 20 mph will support widespread elevated fire
weather concerns today. Some of the windier spots on the western
SD and northeastern WY plains may see near critical to locally
critical fire weather conditions this afternoon. Elevated fire
weather concerns will continue through Sunday and Monday, mainly
across the western SD plains.

Upper low over AZ will swing through NM today before ejecting
into the Southern Plains by early Sunday. Deterministic models in
good consensus of this system staying well to our south and east -
with the sfc low developing over the TX panhandle and hooking
northeast into the midwest by early Monday. Better chances for
light precip arrive later Monday into Tuesday as a shortwave
moving in from the PNW grazes the CWA. LREF grand ensemble paints
30-60% probs for 24- hr precip exceeding 0.1" by Tuesday
afternoon. Beyond Tuesday, deterministic models broadly agree on
west to southwest upper level flow setting up over the CWA with
periodic disturbances bringing occasional low chances for light
precip to the region.

&&

.AVIATION...(For the 12Z TAFS Through 12Z Sunday Morning)
Issued At 512 AM MDT Sat Apr 19 2025

VFR conditions are expected through the forecast period.

&&

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

$$

DISCUSSION/KEY MESSAGES...Wong
AVIATION...26