100
FXUS63 KUNR 281743
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
1143 AM MDT Sun Apr 28 2024

.KEY MESSAGES...

- Widespread precipitation moves in this morning across western
  SD, mainly east and south of Rapid City.

- More seasonable temperatures move in Monday and through the
  week, with near daily chances for showers/storms.

- Elevated fire conditions for Monday and especially Tuesday.

&&

.DISCUSSION...(Today Through Saturday)
Issued at 224 AM MDT Sun Apr 28 2024

Current Water Vapor and upper air models show upper low situated
over western Nebraska this morning, with upper ridge over the
Great Lakes region. Northeasterly surface flow is ongoing with
temps in the 30s to low 40s across the region. Radar is picking up
some patchy light drizzle potential this morning over far western
SD, and highlighting the more widespread precipitation moving up
into south central SD.

Aformentioned upper low swings up into eastern SD today, and wrap
around moisture will over spread from south central SD into
western SD this morning into the afternoon. The more easterly
track of the low compared to previous model runs will limit the
moisture to mostly east and south of Rapid City and the Black
Hills, with the highest amounts expected from central to eastern
SD. Ensemble probability of QPF amounts greater than 0.25" are 60
to 90 percent to the east and south of Wall SD, while areas west
and north of Wall drop to below 30 percent relatively quickly.
Precipitation tapers off from west to east this afternoon and
evening, as the upper low slides up into MN, and weak upper ridge
builds across the Rockies into the northern plains. Upper ridge
will allow for the warmest day of the week on Monday, with highs
climbing back into the 60s. Active upper flow will allow for
almost daily chances for showers and storms as flow becomes more
zonal, highlighting multiple disturbances. A quick moving
shortwave and associated frontal boundary moves just north of the
forecast area Monday night into Tuesday morning. Breezy dry air
behind the front will result in potentially advisory level winds
and elevated fire conditions on Tuesday. Limited moisture with any
of the disturbances early this week will keep low precipitation
amounts with any showers and storms that develop Mon-Weds.
Increasing gulf moisture later in the week may allow for more
significant active weather.


&&

.AVIATION...(For the 18Z TAFS Through 18Z Monday)
Issued At 1140 AM MDT Sun Apr 28 2024

Drizzle and rain with with widespread MVFR/IFR conditions will
slowly improve tonight across western South Dakota. Some fog is
possible overnight across the South Dakota plains, but should
remain east of KRAP. Northeastern WY will remain mostly VFR
through the period, with some localized MVFR/IFR conditions near
the Black Hills this afternoon.

&&

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

$$

DISCUSSION/KEY MESSAGES...Dye
AVIATION...MLS