Alert archive / Iowa / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 159, NWS Des Moines, IA

July 17, 20234 counties in Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Jul 17, 2023, 7:44 AM CDT for 4 counties in Iowa. It was in force for 46 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: Jul 17, 2023, 7:44 AM CDT (12:44 UTC)
Expired: Jul 17, 2023, 8:30 AM CDT
In force: 46 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 50.0 mph

Counties Mahaska County, IA, Marion County, IA, Monroe County, IA, Wapello County, IA

The radar

The Des Moines radar (KDMX), 101 km from the middle of the area, began a volume at 12:47 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 12:00Z, 0.7 hours before the alert went out and 303 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1126 m above ground
0-6 km bulk shear: 54 kt
0-1 km storm-relative helicity: 102 m²/s²
0-3 km storm-relative helicity: 275 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 7.8

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 Jul 17, 6:35 AM CDT, 1 hour 9 minutes earlier.

Area forecast discussion, Jul 17, 6:35 AM CDT, 1 hour 9 minutes before

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Hazardous weather outlook, Jul 17, 4:07 AM CDT, 3 hours 37 minutes before

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In the hours before

Special weather statement, Jul 17, 6:02 AM CDT, 1 hour 42 minutes before

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Local storm report, Jul 17, 6:03 AM CDT, 1 hour 41 minutes before

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Special weather statement, Jul 17, 6:39 AM CDT, 1 hour 5 minutes before

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Local storm report, Jul 17, 7:07 AM CDT, 37 minutes before

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Local storm report, Jul 17, 7:10 AM CDT, 34 minutes before

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Special weather statement, Jul 17, 7:28 AM CDT, 16 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
Jul 17, 1:09 AM CDT	Severe Thunderstorm Warning	DMX	Adair, Audubon, Cass, Guthrie	51 min
Jul 17, 1:24 AM CDT	Severe Thunderstorm Warning	DMX	Adair, Guthrie, Madison	51 min
Jul 17, 2:01 AM CDT	Special Weather Statement	DMX	Warren	29 min
Jul 17, 2:07 AM CDT	Special Weather Statement	DMX	Cass	23 min
Jul 17, 2:15 AM CDT	Special Weather Statement	DMX	Adair	30 min
Jul 17, 3:04 AM CDT	Special Weather Statement	DMX	Adair	26 min
Jul 17, 4:20 AM CDT	Special Weather Statement	DMX	Carroll	25 min
Jul 17, 4:24 AM CDT	Special Weather Statement	DMX	Adair	36 min
Jul 17, 4:58 AM CDT	Severe Thunderstorm Warning	DMX	Audubon, Guthrie	32 min
Jul 17, 5:21 AM CDT	Severe Thunderstorm Warning Considerable damage threat	DMX	Adair, Audubon, Cass, Guthrie	39 min
Jul 17, 5:32 AM CDT	Severe Thunderstorm Warning	DMX	Audubon, Cass	28 min
Jul 17, 5:52 AM CDT	Severe Thunderstorm Warning	DMX	Adair, Adams, Union	23 min
Jul 17, 6:14 AM CDT	Severe Thunderstorm Warning	DMX	Adams, Ringgold, Taylor, Union	31 min
Jul 17, 6:39 AM CDT	Special Weather Statement	DMX	Marion	36 min
Jul 17, 6:53 AM CDT	Severe Thunderstorm Warning	DMX	Mahaska, Marion, Monroe, Wapello	52 min
Jul 17, 8:24 AM CDT	Severe Thunderstorm Warning	DMX	Adair, Cass	51 min
Jul 17, 8:26 AM CDT	Severe Thunderstorm Warning	DMX	Mahaska	34 min
Jul 17, 8:59 AM CDT	Severe Thunderstorm Warning	DMX	Adair, Madison, Union	46 min
Jul 17, 10:05 AM CDT	Special Weather Statement	DMX	Lucas	25 min
Jul 17, 10:34 AM CDT	Special Weather Statement	DMX	Monroe	26 min
Jul 17, 10:56 AM CDT	Special Weather Statement	DMX	Union	34 min
Jul 17, 11:24 AM CDT	Special Weather Statement	DMX	Wapello	21 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.