Sturgis, South Dakota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

368
FXUS63 KUNR 120349
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
949 PM MDT Mon Aug 11 2025

.KEY MESSAGES...

- Seasonably hot and dry conditions are expected through the middle
  of the week

- Elevated to near-critical fire weather conditions may emerge
  Wednesday and Thursday over portions of the area

- Chances for isolated thunderstorms, some severe, return late
  Wednesday

&&

.DISCUSSION...(This Evening Through Monday)
Issued at 252 PM MDT Mon Aug 11 2025

Water vapor imagery this afternoon reveals general troughing from
central CN southwestward through the northern Rockies/Plains.
Embedded therein, multiple weak vorticity maxima are evident in
northwesterly/westerly flow, with a midlevel anticyclone over
ID/MT/WY. A surface trough/front is analyzed over central SD,
demarcated by bands of cumulus/stratocumulus. Additional pockets of
cumulus can be identified over northwestern SD and northeastern WY,
consistent with a strengthening zone of low-level to midlevel
frontogenesis. Breezy northwest winds are observed in spots behind
the surface trough, with gusts of 30 mph or greater over portions of
northeastern WY and northwestern SD.

Despite the aforementioned frontogenesis, the bulk of large-scale
forcing shifts northeast of the region this evening into tonight. As
such, shower/storm activity should be relatively limited. However,
opted to include slight chance PoPs over much of the area this
evening through the early overnight, shifting northwest to southeast
with time. Neutral to rising midlevel heights combined with rising
low-level heights and an expanding thermal ridge tomorrow into early
Wednesday should bring primarily warmer, drier conditions.
Increasingly zonal flow mid-to-late Wednesday is projected to usher
a midlevel shortwave into the region by Wednesday evening/overnight.
LREF mean SBCAPE values of 1000-1500 J/kg combined with 0-6 km shear
vector magnitudes of 25-35 kt may suffice for organized convection
capable of severe updrafts--enough for a level 1 of 5 risk for
severe weather via the SPC. However, the most likely scenario is for
isolated general to strong thunderstorms.

Rising heights in the wake of Wednesday`s wave will bring subsidence
over much of the region through at least early Thursday. Height
rises may continue through the day on Thursday, which would temper
potential for additional showers/storms, especially when combined
with an expanding low-level thermal ridge/associated capping
inversion. If so, concerns for hazardous fire weather conditions
will further increase (outlined more below).

&&

.AVIATION...(For the 06Z TAFS Through 06Z Tuesday Night)
Issued At 948 PM MDT Mon Aug 11 2025

VFR conditions expected through the TAF period.

&&

.FIRE WEATHER...
Issued At 252 PM MDT Mon Aug 11 2025

The arrival of a seasonably hot and dry air mass could bring
elevated to near-critical fire weather conditions to portions of
northeastern WY and southwestern SD Wednesday and Thursday.
Afternoon relative humidity values will drop below 20 percent as
highs climb into the 90s in areas with rapidly drying fuels. Winds
are currently forecast to remain marginal for significant fire
weather conditions, but if gusts of 25-30 mph can emerge, near-
critical fire weather conditions may develop.

&&

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

$$

DISCUSSION/KEY MESSAGES...Sherburn
AVIATION...Wong
FIRE WEATHER...Sherburn