Alert archive / Iowa / Mesoscale Discussions in 2026
Mesoscale Discussion 511
The Storm Prediction Center issued this mesoscale discussion at Apr 23, 2026, 7:41 PM CDT for 22 counties in Iowa; 5 counties in Missouri. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Apr 23, 2026, 7:41 PM CDT (00:41 UTC)
- Expired
- Apr 23, 2026, 9:45 PM CDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Concerning
- Severe thunderstorm watch 138
All 27 counties
Black Hawk County, IA, Bremer County, IA, Butler County, IA, Chickasaw County, IA, Clarke County, IA, Decatur County, IA, Floyd County, IA, Franklin County, IA, Grundy County, IA, Hardin County, IA, Jasper County, IA, Lucas County, IA, Madison County, IA, Marion County, IA, Marshall County, IA, Polk County, IA, Ringgold County, IA, Story County, IA, Tama County, IA, Union County, IA, Warren County, IA, Wayne County, IA, Andrew County, MO, DeKalb County, MO, Gentry County, MO, Harrison County, MO, Worth County, MO
The radar
The Des Moines radar (KDMX), 29 km from the middle of the area, began a volume at 00:45 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 nearest sounding before it
Omaha, NE (KOAX), launched 00:00Z, 0.7 hours before the alert went out and 235 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
- 2 J/kg
- Mixed-layer CIN
- -106 J/kg
- Mixed-layer LCL
- 2615 m above ground
- 0-6 km bulk shear
- 62 kt
- 0-1 km storm-relative helicity
- -161 m²/s²
- 0-3 km storm-relative helicity
- -99 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -2.3
The text
As transmitted.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 23, 8:59 PM CDT | Mesoscale Discussion | SPC | Appanoose, Benton, Cedar, Davis, Henry, Iowa and 15 more | 91 min |
| Apr 23, 8:59 PM CDT | Severe Thunderstorm Watch | SPC | Benton, Buchanan, Cedar, Delaware, Des Moines, Dubuque and 12 more | 3 hr |
| Apr 23, 9:51 PM CDT | Severe Thunderstorm Watch | SPC | Barry, Barton, Cedar, Christian, Dade, Greene and 8 more | 6 hr |
| Apr 23, 11:50 PM CDT | Mesoscale Discussion | SPC | Barry, Barton, Cedar, Dade, Jasper, Lawrence and 3 more | 115 min |
| Apr 24, 2:00 AM CDT | Mesoscale Discussion | SPC | Christian, Douglas, Howell, Laclede, Ozark, Stone and 4 more | 90 min |
Nearby
Mesoscale Discussions in Iowa, 2026Mesoscale Discussions in Missouri, 2026Every mesoscale discussion 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.