Alert archive / Iowa / Severe Thunderstorm Warnings in 2025

Severe Thunderstorm Warning 267, NWS Sioux Falls, SD

August 9, 2025Cherokee County, Iowa

NWS Sioux Falls, SD issued this severe thunderstorm warning at Aug 9, 2025, 3:21 AM CDT for Cherokee County, Iowa. It was in force for 39 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Aug 9, 2025, 3:21 AM CDT (08:21 UTC)
Expired: Aug 9, 2025, 4:00 AM CDT
In force: 39 min
Issued by: NWS Sioux Falls, SD
Area: Storm-based polygon
Hail: 1.25 in
Wind: 60.0 mph

County Cherokee County, IA

The radar

The Sioux Falls radar (KFSD), 130 km from the middle of the area, began a volume at 08:25 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Aug 8, 9:34 PM CDT	Severe Thunderstorm Watch	SPC	8 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 8.4 hours before the alert went out and 169 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 4205 J/kg
Mixed-layer CIN: -214 J/kg
Mixed-layer LCL: 1448 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 87 m²/s²
0-3 km storm-relative helicity: 94 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 4.6

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Sioux Falls, SD wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 8, 10:30 PM CDT, 4 hours 51 minutes earlier.

Area forecast discussion, Aug 8, 10:30 PM CDT, 4 hours 51 minutes before

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Hazardous weather outlook, Aug 8, 10:42 PM CDT, 4 hours 39 minutes before

Hazardous Weather Outlook
National Weather Service Sioux Falls SD
1042 PM CDT Fri Aug 8 2025

IAZ001>003-012>014-020>022-031-032-MNZ071-072-080-081-089-090-097-
098-NEZ013-014-SDZ038>040-050-052>071-100345-
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-
1042 PM CDT Fri Aug 8 2025

This Hazardous Weather Outlook is for 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 thunderstorms will be possible east of Interstate 29 through
midnight with half dollar size hail and winds gusts up to 70 mph
being the main threats. Toward early Saturday morning additional
isolated severe storms may lift out of Nebraska into parts of
northwest Iowa with half dollar hail and wind gusts to 70 mph again
being the main threats.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

No hazardous weather expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

The office that day

Everything else NWS Sioux Falls, SD issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 9, 3:41 AM CDT	Flash Flood Warning	FSD	Cherokee	3 hr
Aug 9, 3:59 AM CDT	Severe Thunderstorm Warning	FSD	Cherokee	26 min
Aug 9, 4:10 AM CDT	Severe Thunderstorm Warning Considerable damage threat	FSD	Buena Vista, Cherokee, Ida	50 min
Aug 9, 5:44 AM CDT	Severe Thunderstorm Warning	FSD	Ida	16 min
Aug 9, 7:06 AM CDT	Severe Thunderstorm Warning	FSD	Ida, Woodbury	54 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2025 Every severe thunderstorm warning in 2025

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.