Alert archive / Iowa / Severe Thunderstorm Warnings in 2026

Severe Thunderstorm Warning 18, NWS Sioux Falls, SD

April 23, 2026Woodbury County, Iowa

NWS Sioux Falls, SD issued this severe thunderstorm warning at Apr 23, 2026, 12:12 PM CDT for Woodbury County, Iowa. It was in force for 48 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
Apr 23, 2026, 12:12 PM CDT (17:12 UTC)
Expired
Apr 23, 2026, 1:00 PM CDT
In force
48 min
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon
Hail
1.25 in
Wind
60.0 mph

County Woodbury County, IA

The radar

The Omaha radar (KOAX), 122 km from the middle of the area, began a volume at 17:11 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.

IssuedProductOfficeLasted
Apr 23, 12:02 PM CDTTornado WatchSPC7 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 5.2 hours before the alert went out and 337 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-pSkew-T log-p diagram, Minneapolis, MN at 12:00Z on 2026-04-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 12:00Z on 2026-04-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 222 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
830 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
222 m²/s²
0-3 km storm-relative helicity
96 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

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 Apr 23, 6:46 AM CDT, 5 hours 26 minutes earlier.

Area forecast discussion, Apr 23, 6:46 AM CDT, 5 hours 26 minutes before
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Hazardous weather outlook, Apr 23, 3:30 AM CDT, 8 hours 42 minutes before
Hazardous Weather Outlook
National Weather Service Sioux Falls SD
330 AM CDT Thu Apr 23 2026

IAZ001>003-012>014-020>022-031-032-MNZ080-081-089-090-098-NEZ013-014-
SDZ071-240830-
Lyon-Osceola-Dickinson-Sioux-O'Brien-Clay-Plymouth-Cherokee-
Buena Vista-Woodbury-Ida-Murray-Cottonwood-Nobles-Jackson-Rock-Dixon-
Dakota-Union-
330 AM CDT Thu Apr 23 2026

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

.DAY ONE...Today and tonight.

Scattered showers and thunderstorms will be possible this afternoon
and evening. A few storms could become severe with large hail up to
half dollar size and damaging winds up to 60 mph being the primary
threats.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

No hazardous weather expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed.

MNZ071-072-097-SDZ038>040-050-052>070-240830-
Lincoln-Lyon-Pipestone-Beadle-Kingsbury-Brookings-Gregory-Jerauld-
Sanborn-Miner-Lake-Moody-Brule-Aurora-Davison-Hanson-McCook-
Minnehaha-Charles Mix-Douglas-Hutchinson-Turner-Bon Homme-Yankton-
Clay-
330 AM CDT Thu Apr 23 2026

This Hazardous Weather Outlook is for southwest Minnesota, central
South Dakota, east central South Dakota, south central South Dakota
and southeast South Dakota.

.DAY ONE...Today and tonight.

A few scattered showers with an occasional rumble of thunder will be
possible through the morning.

Elevated to critical fire danger is expected today as westerly to
northwesterly winds strengthen behind a cold front. This combined
with low relative humidity values will create a favorable environment
for fire spread. Avoid any outdoor burning and heed your local
restrictions.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

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.

IssuedProductOfficeCountiesLasted
Apr 23, 2:13 AM CDTRed Flag WarningFSDAurora, Beadle, Bon Homme, Brookings, Brule, Charles Mix and 16 more18 hr
Apr 23, 12:48 PM CDTSevere Thunderstorm WarningFSDPlymouth, Woodbury42 min
Apr 23, 3:12 PM CDTSevere Thunderstorm WarningFSDBuena Vista, Cherokee48 min
Apr 23, 3:27 PM CDTSevere Thunderstorm WarningFSDIda, Woodbury48 min
Apr 23, 3:37 PM CDTSevere Thunderstorm WarningFSDClay38 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2026Every severe thunderstorm warning in 2026

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.