Alert archive / Iowa / Severe Thunderstorm Warnings in 2026
Severe Thunderstorm Warning 337, NWS Des Moines, IA
NWS Des Moines, IA issued this severe thunderstorm warning at Sep 14, 2026, 7:40 PM CDT for 4 counties in Iowa. It was in force for 50 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
- Sep 14, 2026, 7:40 PM CDT (00:40 UTC)
- Expired
- Sep 14, 2026, 8:30 PM CDT
- In force
- 50 min
- Issued by
- NWS Des Moines, IA
- Area
- Storm-based polygon
- Hail
- 0.75 in
- Wind
- 60.0 mph
Counties Adair County, IA, Audubon County, IA, Cass County, IA, Guthrie County, IA
The radar
The Des Moines radar (KDMX), 85 km from the middle of the area, began a volume at 00:39 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 |
|---|---|---|---|
| Sep 14, 4:51 PM CDT | Tornado Watch | SPC | 7 hr |
The nearest sounding before it
Omaha, NE (KOAX), launched 00:00Z, 0.7 hours before the alert went out and 141 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.
- Mixed-layer CAPE
- 1901 J/kg
- Mixed-layer CIN
- -88 J/kg
- Mixed-layer LCL
- 1352 m above ground
- 0-6 km bulk shear
- 56 kt
- 0-1 km storm-relative helicity
- 227 m²/s²
- 0-3 km storm-relative helicity
- 316 m²/s²
- Significant tornado parameter
- 1.6
- Supercell composite
- 14.9
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 Des Moines, IA wrote its last area forecast discussion before this severe thunderstorm warning went out at Sep 14, 6:45 PM CDT, 55 minutes earlier.
Area forecast discussion, Sep 14, 6:45 PM CDT, 55 minutes before
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</html>Hazardous weather outlook, Sep 14, 4:11 PM CDT, 3 hours 29 minutes before
Hazardous Weather Outlook National Weather Service Des Moines IA 411 PM CDT Mon Sep 14 2026 IAZ025>028-034>039-045>050-057>062-070>074-081>084-092>095-152115- Wright-Franklin-Butler-Bremer-Calhoun-Webster-Hamilton-Hardin- Grundy-Black Hawk-Carroll-Greene-Boone-Story-Marshall-Tama- Audubon-Guthrie-Dallas-Polk-Jasper-Poweshiek-Cass-Adair-Madison- Warren-Marion-Adams-Union-Clarke-Lucas-Taylor-Ringgold-Decatur- Wayne- 411 PM CDT Mon Sep 14 2026 This Hazardous Weather Outlook is for portions of central Iowa. .DAY ONE...Tonight A Flash Flood Watch is in effect for the area. Please see our website at weather.gov/dmx for additional details. There is a Moderate Risk of excessive rainfall. Repeated rounds of heavy rainfall will likely bring instances of flash flooding overnight. There is a Slight Risk of severe weather late this afternoon through this evening, mainly across portions of west central into central Iowa. All modes of severe weather may be possible including large hail, damaging winds, and perhaps even a few tornadoes. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday A Flash Flood Watch is in effect for the area through midday Wednesday. Please see our website at weather.gov/dmx for additional details. Additional rounds of thunderstorms and heavy rainfall are expected at times from Tuesday through much of this week. Flash flooding and river flooding will become more of a threat with each round of heavy rain. .SPOTTER INFORMATION STATEMENT... && NWS Des Moines will discontinue the Hazardous Weather Outlook product (HWO) on September 30th, 2026. Weather hazards and outlooks will continue to be provided through the standard forecast channels, including weather briefing packets, forecast discussions, weather story graphics, the experimental graphical hazardous weather outlook, and updated hazard messaging. All local products and visual tools are accessible directly at weather.gov/desmoines. IAZ004>007-015>017-023-024-033-044-075-085-086-096-097-152115- Emmet-Kossuth-Winnebago-Worth-Palo Alto-Hancock-Cerro Gordo- Pocahontas-Humboldt-Sac-Crawford-Mahaska-Monroe-Wapello-Appanoose- Davis- 411 PM CDT Mon Sep 14 2026 This Hazardous Weather Outlook is for portions of central Iowa. .DAY ONE...Tonight Thunderstorms with heavy rainfall are expected. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday Additional rounds of thunderstorms and heavy rainfall are expected at times from Tuesday through much of this week. Flash flooding and river flooding will become more of a threat with each round of heavy rain. .SPOTTER INFORMATION STATEMENT... && NWS Des Moines will discontinue the Hazardous Weather Outlook product (HWO) on September 30th, 2026. Weather hazards and outlooks will continue to be provided through the standard forecast channels, including weather briefing packets, forecast discussions, weather story graphics, the experimental graphical hazardous weather outlook, and updated hazard messaging. All local products and visual tools are accessible directly at weather.gov/desmoines.
The office that day
Everything else NWS Des Moines, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 14, 8:24 PM CDT | Severe Thunderstorm Warning | DMX | Adair, Adams, Cass, Dallas, Guthrie, Madison and 1 more | 51 min |
| Sep 15, 1:01 AM CDT | Special Weather Statement | DMX | Audubon, Guthrie | 29 min |
| Sep 15, 1:28 AM CDT | Special Weather Statement | DMX | Audubon, Cass, Guthrie | 32 min |
| Sep 15, 1:43 AM CDT | Severe Thunderstorm Warning | DMX | Adair, Audubon, Cass, Guthrie | 32 min |
| Sep 15, 2:01 AM CDT | Severe Thunderstorm Warning | DMX | Adair, Guthrie | 29 min |
| Sep 15, 2:25 AM CDT | Special Weather Statement | DMX | Dallas | 35 min |
| Sep 15, 3:01 AM CDT | Flash Flood Warning | DMX | Adair, Audubon, Cass, Dallas, Guthrie, Madison | 4 hr |
| Sep 15, 4:19 AM CDT | River Flood Watch | DMX | Polk | 5 hr |
| Sep 15, 6:59 AM CDT | River Flood Watch | DMX | Polk | 8 hr |
| Sep 15, 8:08 AM CDT | River Flood Watch | DMX | Cass | 8 hr |
| Sep 15, 1:45 PM CDT | River Flood Warning | DMX | Polk | 28 hr |
| Sep 15, 2:13 PM CDT | River Flood Warning | DMX | Dallas, Polk | 4 hr |
| Sep 15, 3:30 PM CDT | Areal Flood Warning | DMX | Adair | 22 hr |
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.