Alert archive / Iowa / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 61, NWS Des Moines, IA

May 7, 2023Davis County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at May 7, 2023, 12:40 AM CDT for Davis County, 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: May 7, 2023, 12:40 AM CDT (05:40 UTC)
Expired: May 7, 2023, 1:30 AM CDT
In force: 50 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Hail: 1.25 in
Wind: 60.0 mph

County Davis County, IA

The radar

The Des Moines radar (KDMX), 155 km from the middle of the area, began a volume at 05:41 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

Davenport, (KDVN), launched 00:00Z, 5.7 hours before the alert went out and 187 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: 668 J/kg
Mixed-layer CIN: -146 J/kg
Mixed-layer LCL: 1150 m above ground
0-6 km bulk shear: 41 kt
0-1 km storm-relative helicity: 55 m²/s²
0-3 km storm-relative helicity: 158 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 1.6

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 Des Moines, IA wrote its last area forecast discussion before this severe thunderstorm warning went out at May 6, 11:57 PM CDT, 43 minutes earlier.

Area forecast discussion, May 6, 11:57 PM CDT, 43 minutes before

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Hazardous weather outlook, May 6, 10:50 PM CDT, 1 hour 50 minutes before

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In the hours before

Special weather statement, May 6, 8:01 PM CDT, 4 hours 39 minutes before

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Special weather statement, May 6, 8:33 PM CDT, 4 hours 7 minutes before

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Special weather statement, May 6, 9:36 PM CDT, 3 hours 4 minutes before

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The office that day

Everything else NWS Des Moines, IA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 6, 8:01 PM CDT	Special Weather Statement	DMX	Davis	29 min
May 6, 8:33 PM CDT	Special Weather Statement	DMX	Davis	12 min
May 6, 10:41 PM CDT	Dense Fog Advisory	DMX	Adair, Adams, Audubon, Black Hawk, Boone, Bremer and 36 more	12 hr
May 7, 8:53 AM CDT	Special Weather Statement	DMX	Greene	37 min
May 7, 10:04 AM CDT	Special Weather Statement	DMX	Story	41 min
May 7, 12:45 PM CDT	Severe Thunderstorm Warning	DMX	Calhoun, Carroll, Crawford, Sac	45 min
May 7, 1:24 PM CDT	Severe Thunderstorm Warning	DMX	Carroll, Greene	51 min
May 7, 2:03 PM CDT	Severe Thunderstorm Warning	DMX	Boone, Greene, Webster	26 min
May 7, 2:56 PM CDT	Severe Thunderstorm Warning	DMX	Boone, Hamilton, Hardin, Marshall, Story	49 min
May 7, 3:30 PM CDT	Severe Thunderstorm Warning	DMX	Jasper, Marshall, Story	45 min
May 7, 3:40 PM CDT	Severe Thunderstorm Warning	DMX	Grundy, Hardin, Marshall, Story, Tama	32 min
May 7, 3:49 PM CDT	Severe Thunderstorm Warning	DMX	Tama	26 min
May 7, 3:51 PM CDT	Severe Thunderstorm Warning	DMX	Jasper, Poweshiek	39 min
May 7, 4:15 PM CDT	Severe Thunderstorm Warning	DMX	Jasper, Marshall, Poweshiek, Tama	45 min
May 7, 4:46 PM CDT	Severe Thunderstorm Warning Destructive damage threat	DMX	Poweshiek, Tama	44 min
May 7, 5:01 PM CDT	Severe Thunderstorm Warning	DMX	Jasper, Mahaska, Poweshiek	44 min
May 7, 5:38 PM CDT	Severe Thunderstorm Warning Considerable damage threat	DMX	Mahaska	15 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2023 Every severe thunderstorm warning in 2023

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.