570
FXUS63 KFSD 220854
AFDFSD

Area Forecast Discussion
National Weather Service Sioux Falls SD
354 AM CDT Wed Jul 22 2026

.KEY MESSAGES...

- Temperatures remain below normal for the rest of the work
  week. Departures from normal will average 5 to 8 degrees below
  normal.

- Outside of light rain chances this morning and Thursday
  night, much of the 7 day forecast is dry.

- Temperatures this weekend into early next week rise well above
  normal with highs well into the 90s in most locations. Heat
  related headlines may be needed at times this weekend.

&&

.UPDATE...
Issued at 350 AM CDT Wed Jul 22 2026

Taking a look across the area, the forecast remains on track with
scattered showers developing across the Black Hills then streaming
into areas along and south of the Missouri River Valley. Current
observations continue to suggest this developing activity is
fighting drier air near the surface. However, should see an uptick
in development closer to daybreak as mid-level frontal forcing
strengthens with an arriving shortwave. While the better plume of
moisture will likely be focused across southcentral SD and
along/south of the Missouri River Valley, can`t completely rule out
some sprinkles to very light showers as far east as the James River
Valley. Nonetheless, the further east you go the more dry air gets
introduced with the surface high overhead. Should see this activity
continue to feaster through late afternoon before tapering off.
Otherwise, persistent cloud cover and lighter surface winds will
keep temperatures below normal for most areas with highs mainly in
the low to upper 70s except across southcentral SD where cooler
highs in the upper 60s are expected.

&&

.DISCUSSION...
Issued at 1252 PM CDT Tue Jul 21 2026

THIS AFTERNOON: Plenty of cool air aloft has poured southward into
the region, with morning strato-cu continuing to slowly mix upwards.
 High temperatures given the cloud cover will remain in the upper
70s to lower 80s. Aloft, the increasing northwesterly flow could
bring high level smoke though the region into the night.

TONIGHT: Surface high pressure drifts into the Midwest and western
Great Lakes region overnight.  Winds turn light and variable which,
may lead to fairly cool overnight lows in areas east of the James
River.  The low-lvl airmass is fairly dry, so fog probabilities will
remain very localized to sheltered valleys and riverways.
Further west, high level clouds increase after midnight as mid-
lvl warm advection focuses over the West River areas and the
Nebraska panhandle. A few sprinkles to light rain showers may
reach the central portions of SD into the James River valley by
daybreak.

WEDNESDAY:  A subtle shortwave drops southeast from the Black Hills
region across central Nebraska during Wednesday. Much of the
CWA will remain under the influence of low-lvl dry air advection
from the northeast during the day. While mid-lvl lift spread
east towards the I-29 corridor, most guidance struggles to
produce more than sprinkles east of I-29, with the best low-lvl
saturation focused along and south of the MO River valley. Any
QPF that falls will be light. The most impact from this system
may be increased cloud cover and temperatures in the 70s and
80s.

THURSDAY: After another night with variable cloud cover, light
winds, and cooler temperatures, Thursday will see surface winds
return back to the South early in the day. We`ll be watching another
slightly stronger wave cross the Rockies during the day on Thursday.
Model guidance has been a bit all over with this wave, with the GFS
and about 40% of it`s ensemble members stubbornly further to the NE
than all of the other major model guidance. The ECMWF/ICON/GEM/UKMET
and to some degree NAM force this wave further southeast bringing
the majority of rain chances to western SD, central and
northern NE and western Iowa. The latest NBM has hedged a bit
more towards the drier solutions as more drier input is
received, and I continue to favor the greatest focus for rain
along the MO River valley. That said, if there is some shift
towards the outlier solutions, moisture convergence could be
enough to at least produce some meaningful rain into Thursday
night.

FRIDAY-MONDAY: A 600 DM ridge builds through the Central Plains
heading into the upcoming weekend.  This ridge, unlike the past
weeks, it a bit more suppressed which may serve to delay the most
intense heat into the second half of the weekend.  Temperatures are
likely to surge into the 90s Saturday and Sunday with initial focus
for the hottest temperatures west of the James River Saturday and
then further east Sunday.  Even with the slightly warm biased NBM,
there is some potential for heat related headlines this weekend.
Convection chances remain low for Saturday, but may rise slightly on
the edge of the EML late Sunday. A very hot Monday is also
possible with a similar setup for weak flow convection on the
edge of the EML in the afternoon evening.

&&

.AVIATION /06Z TAFS THROUGH 06Z THURSDAY/...
Issued at 1230 AM CDT Wed Jul 22 2026

Mid-high level clouds will continue to expand east through
midday Wednesday, before slowly sagging southward into Nebraska
through the afternoon and evening. Variable winds will remain
light (at or below 10kt) through the period.

Light rain showers/sprinkles may accompany the thicker mid-level
clouds through portions of the James and Missouri River Valleys
late tonight into Wednesday afternoon. A few sprinkles may brush
KHON/KFSD with a slightly better chance at light rain impacting
KSUX at times in the afternoon. Conditions within any showers
should remain VFR with no thunder expected.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
IA...None.
NE...None.

&&

$$

UPDATE...05
DISCUSSION...Dux
AVIATION...JH