456
FXUS63 KUNR 271007
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
407 AM MDT Fri Sep 27 2024

.KEY MESSAGES...

- Dry weather, much warmer than average temperatures, and elevated
  to critical fire weather conditions continue through the weekend.

- Cooler to start next week, then warming again.

&&

.DISCUSSION...(Today Through Thursday)
Issued at 147 AM MDT Fri Sep 27 2024

08Z analysis shows the upper trough and surface front have moved
off to the southeast of the forecast area. Skies are clear.

Dry weather and much warmer than average temperatures will
continue through the weekend as the southwest CONUS ridge
rebuilds over the northern plains.

With the surface high sliding off to the east and surface low
developing over Alberta/Saskatchewan, northerly winds early this
morning will become southerly over northeastern Wyoming and far
western South Dakota again today, becoming breezy over
northeastern Wyoming and northwestern South Dakota.

High temperatures this afternoon will be about 10 degrees cooler
than yesterday, but still well above average for late September.
With the upper ridge rebounding, temperatures will rise again for
Saturday, with Sunday temps even warmer, similar to today.
Elevated to at least near critical fire weather conditions can be
expected today through Sunday, with Sunday the most likely day for
widespread critical fire wx conditions.

The upper level trough will cross the northern Plains late Sunday
night and Monday, but with very little moisture, chances for any
rainfall still look to be 10 percent or less. The associated cold
front will arrive Sunday night, ushering in cooler air, along
with gusty winds, for Sunday night and Monday. High temps will
finally drop back to near average levels, mostly 60s and lower
70s, for Monday and Tuesday. Zonal flow aloft/weak ridging will
develop behind the trough toward midweek, with above average temps
returning for at least Wednesday. Latest ensemble output is
showing good potential for another upper trough and cold front
arriving sometime late week and this one could bring at least a
chance for precipitation.

&&

.AVIATION...(For the 12Z TAFS Through 12Z Saturday Morning)
Issued At 407 AM MDT Fri Sep 27 2024

VFR conditions will continue through the TAF period.

&&

.FIRE WEATHER...
Issued At 147 AM MDT Fri Sep 27 2024

Slightly cooler air and slightly higher humidity are in place
today, but elevated fire weather conditions are expected at many
locations today into Saturday, with near critical conditions over
parts of northeastern Wyoming. Very warm to hot conditions return
for the weekend, especially on Sunday. Sunday looks to be the
most favorable day for Red Flag potential as south to southwest
winds increase ahead of an approaching cold front. Minimum
humidity is forecast to drop into the lower teens in most areas on
Sunday afternoon. Another dry cold front arriving late Sunday,
will bring much cooler conditions, higher humidity, and gusty
winds Sunday night and Monday.

&&

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

$$

DISCUSSION/KEY MESSAGES...10
AVIATION...10
FIRE WEATHER...10