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000
FXUS63 KUNR 222026
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
226 PM MDT Mon Apr 22 2024

.KEY MESSAGES...

- Dry weather through Wednesday, along with warming temperatures.

- Turning unsettled late this week. Chances for showers and
  thunderstorms returning by Thurs and continuing into the
  weekend.

- Breezy at times this week.

&&

.DISCUSSION...(This Evening Through Monday)
Issued at 225 PM MDT Mon Apr 22 2024

An upper low is crossing south central Canada at this time, with
west/northwest flow over the northern Plains. This system will
push ESE into the Midwest Tuesday morning. Breezy northwest winds
will continue this afternoon, then decrease through the evening
hours. A few sites have had gusts of 50 mph or higher this
afternoon, so will let the Wind Advisory continue, which expires
at 02z. Upper ridging will build across the region Tuesday and
Wednesday. Surface high pressure will cross the CWA tomorrow, then
return flow sets up Wednesday which will begin the ramp up in
Theta E for the latter part of the week. Highs Wednesday will
reach the 70s across some locations, then 70s and even lower 80s
on Thursday. A shortwave trough is progged to cross the region
Thursday, which will bring chances of showers and thunderstorms.
Surface CAPE could be up to 1000 J/kg, but shear appears to be
relatively weak, so severe weather is not expected. Can`t rule out
a stronger storm or two, however. NAM does suggest PWATs reaching
150-200% of normal on Thursday, so locally heavy rain will be
possible. Low pressure will cross the region on Friday, bringing
continued chances for rain, especially as wrap-around precip
slowly pushes through. Models are showing central South Dakota as
having the best chances for one inch or more of total QPF Thursday
and Friday. A second system will cross the central to northern
Great Plains this weekend, but there is a bit more uncertainty on
the track of this system. The 12z GFS is farther east, which is
closer to the ECM solution where the bulk of precip stays just
east of the CWA. Will keep an eye on this trend.

&&

.AVIATION...(For the 18Z TAFS Through 18Z Tuesday)
Issued At 1117 AM MDT Mon Apr 22 2024

VFR conditions are expected through the TAF period. Northwest
winds will gust to 35-45kts this afternoon across northwest SD.
Winds will diminish this evening and pick back up again over
northwest SD Wednesday morning.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...Wind Advisory until 8 PM MDT this evening for SDZ001-002-012>014-
     078.
WY...None.
&&

$$

DISCUSSION/KEY MESSAGES...13
AVIATION...Helgeson