Alert archive / Iowa / Severe Thunderstorm Warnings in 2022

Severe Thunderstorm Warning 147, NWS Des Moines, IA

August 18, 2022Emmet County, Kossuth County, Palo Alto County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Aug 18, 2022, 7:21 PM CDT for Emmet County, Kossuth County, Palo Alto County, Iowa. It was in force for 39 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: Aug 18, 2022, 7:21 PM CDT (00:21 UTC)
Expired: Aug 18, 2022, 8:00 PM CDT
In force: 39 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Hail: 0.88 in
Wind: 60.0 mph

Counties Emmet County, IA, Kossuth County, IA, Palo Alto County, IA

The radar

The Des Moines radar (KDMX), 178 km from the middle of the area, began a volume at 00:22 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, 0.4 hours before the alert went out and 260 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: 1016 J/kg
Mixed-layer CIN: -82 J/kg
Mixed-layer LCL: 1810 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: 7 m²/s²
0-3 km storm-relative helicity: 94 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

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 Aug 18, 6:59 PM CDT, 22 minutes earlier.

Area forecast discussion, Aug 18, 6:59 PM CDT, 22 minutes before

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Hazardous weather outlook, Aug 18, 3:29 PM CDT, 3 hours 52 minutes before

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In the hours before

Special weather statement, Aug 18, 6:58 PM CDT, 23 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
Aug 18, 8:00 PM CDT	Special Weather Statement	DMX	Kossuth	30 min
Aug 18, 8:41 PM CDT	Special Weather Statement	DMX	Crawford	34 min
Aug 18, 9:39 PM CDT	Severe Thunderstorm Warning	DMX	Carroll, Crawford, Sac	36 min
Aug 19, 2:23 PM CDT	Severe Thunderstorm Warning	DMX	Dallas, Jasper, Madison, Polk, Warren	52 min
Aug 19, 2:48 PM CDT	Special Weather Statement	DMX	Audubon	27 min
Aug 19, 2:57 PM CDT	Special Weather Statement	DMX	Hardin	33 min
Aug 19, 3:03 PM CDT	Severe Thunderstorm Warning	DMX	Jasper	27 min
Aug 19, 3:09 PM CDT	Severe Thunderstorm Warning	DMX	Grundy, Hardin	51 min
Aug 19, 3:55 PM CDT	Severe Thunderstorm Warning	DMX	Black Hawk, Grundy	34 min
Aug 19, 4:03 PM CDT	Severe Thunderstorm Warning	DMX	Jasper, Poweshiek	42 min
Aug 19, 4:26 PM CDT	Severe Thunderstorm Warning	DMX	Jasper, Polk	30 min
Aug 19, 4:34 PM CDT	Severe Thunderstorm Warning	DMX	Marion	41 min
Aug 19, 4:36 PM CDT	Severe Thunderstorm Warning	DMX	Poweshiek, Tama	24 min
Aug 19, 4:40 PM CDT	Severe Thunderstorm Warning	DMX	Adair, Adams, Cass, Union	29 min
Aug 19, 4:50 PM CDT	Flash Flood Warning	DMX	Polk	3 hr
Aug 19, 5:36 PM CDT	Severe Thunderstorm Warning	DMX	Mahaska, Marion, Monroe	39 min
Aug 19, 6:09 PM CDT	Special Weather Statement	DMX	Mahaska	36 min
Aug 19, 6:28 PM CDT	Severe Thunderstorm Warning	DMX	Mahaska, Marion, Monroe	35 min
Aug 19, 6:49 PM CDT	Special Weather Statement	DMX	Butler, Grundy	41 min
Aug 19, 6:53 PM CDT	Special Weather Statement	DMX	Mahaska	37 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2022 Every severe thunderstorm warning in 2022

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.