Severe Thunderstorm Warning 332, NWS Sioux Falls, SD

Area Forecast Discussion
National Weather Service Sioux Falls SD
Issued by National Weather Service Aberdeen SD
628 PM CDT Mon Sep 22 2025

.KEY MESSAGES...

- Scattered thunderstorms possible late this afternoon into the
  early overnight hours. Ping pong ball-sized hail and wind
  gusts to 60 mph are the main threats from the strongest
  storms.

- A persistent seasonally warm pattern will be in place Tuesday
  through early next week with very small chances for
  precipitation.

- Patchy fog possible on Tuesday morning.

&&

.UPDATE...
Issued at 623 PM CDT Mon Sep 22 2025

We continue to monitor a broken line of convection across
O'Brian and Clay Counties as it slowly sinks southeast. CAMs
continue to show this southern progression as well as the
potential for additional development west of the current storms.

&&

.DISCUSSION...
Issued at 206 PM CDT Mon Sep 22 2025

The tail end of an exiting wave will bring a small chance for
some diurnally driven thunderstorms into parts of northwest IA
late this afternoon into the evening. With close to 2000 J/kg
CAPE in this environment and fairly weak shear, a few severe
storms will be possible. The main threats from the strongest
storms would be ping pong ball-sized hail and wind gusts to 60
mph. During the evening and night-time hours a wave will move
through NE and another shot for storms along the NE/SD border
towards Sioux City. These storms may also produce a few stronger
updrafts with weak shear and about 1500 J/kg CAPE.

Once the thunderstorm threat passes tonight a ridge of high
pressure will settle into northern and central SD. This will
bring some cooler morning readings with at least a small chance
of a few locations sneaking into the upper 40s near highway 14.
With a marginally moist ground in places and light winds, some
patchy fog will again be possible, with the better chances near
and north of I-90.

Cooler high pressure builds south and brings about a seasonally
warm day on Tuesday with relatively light winds. A small
corridor around highway 81 and I-29 may see some spotty
diurnally driven showers Tuesday afternoon. Skinny CAPE with
values less than about 300 J/kg. Fairly low confidence in this
occurrence.

A dry and warm pattern develops Wednesday into the weekend with
very little if any chance for precipitation. One stronger wave
does move by to the north on Friday and brings a nice warm nose
into the area, so a very small chance for a shower or
thunderstorm on Friday. With this warm nose Friday, should also
prove to be the warmest with some mid and possibly upper 80s for
highs. Another warm nose may sneak into the area Sunday night
into Monday and bring another very small chance, but once again
too low to mention. Outside of Friday, Wednesday through early
next week should see highs in the 70s to lower 80s.

&&

.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 623 PM CDT Mon Sep 22 2025

VFR conditions are expected over the next 24 hours at
HON/FSD/SUX. The main concern will be with the initial
thunderstorm activity northeast of SUX. Forecast solutions show
the potential of at least PROB30/TEMPO30 from around 01-05Z this
evening. There is also the potential for fog at at least
HON/FSD around daybreak, so have kept the potential for 4SM BR
at that time.

&&

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

&&

UPDATE...06
DISCUSSION...08
AVIATION...06

Hazardous Weather Outlook
National Weather Service Sioux Falls SD
Issued by National Weather Service Aberdeen SD
437 PM CDT Mon Sep 22 2025

IAZ001>003-012>014-020>022-031-032-MNZ071-072-080-081-089-090-097-
098-NEZ013-014-SDZ038>040-050-052>071-232145-
Lyon-Osceola-Dickinson-Sioux-O'Brien-Clay-Plymouth-Cherokee-
Buena Vista-Woodbury-Ida-Lincoln-Murray-Cottonwood-Nobles-Jackson-
Pipestone-Rock-Dixon-Dakota-Beadle-Kingsbury-Brookings-Gregory-
Jerauld-Sanborn-Miner-Lake-Moody-Brule-Aurora-Davison-Hanson-
McCook-Minnehaha-Charles Mix-Douglas-Hutchinson-Turner-Bon Homme-
Yankton-Union-
437 PM CDT Mon Sep 22 2025

This Hazardous Weather Outlook is for portions of northwest Iowa,
west central Iowa, southwest Minnesota, northeast Nebraska,
central South Dakota, east central South Dakota, south central
South Dakota, and southeast South Dakota.

.DAY ONE...Tonight

Isolated strong to severe thunderstorms are possible through this
evening. The highest chances will be south of I-90. A few storms
may become strong to severe with ping-pong ball sized hail and
damaging winds up to 60 mph being the primary threats.

Patchy dense fog is possible overnight into Tuesday.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday

Patchy dense fog is possible Tuesday morning.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

06