Alert archive / Iowa / Severe Thunderstorm Warnings in 2022

Severe Thunderstorm Warning 161, NWS Des Moines, IA

August 27, 2022Jasper County, Poweshiek County, Tama County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Aug 27, 2022, 4:51 PM CDT for Jasper County, Poweshiek County, Tama County, Iowa. It was in force for 21 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 27, 2022, 4:51 PM CDT (21:51 UTC)
Expired: Aug 27, 2022, 5:12 PM CDT
In force: 21 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 50.0 mph

Counties Jasper County, IA, Poweshiek County, IA, Tama County, IA

The radar

The Des Moines radar (KDMX), 85 km from the middle of the area, began a volume at 21:50 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

Minneapolis, MN (KMPX), launched 12:00Z, 9.9 hours before the alert went out and 345 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: 127 J/kg
Mixed-layer CIN: -295 J/kg
Mixed-layer LCL: 785 m above ground
0-6 km bulk shear: 36 kt
0-1 km storm-relative helicity: 494 m²/s²
0-3 km storm-relative helicity: 516 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 2.5

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 27, 2:23 PM CDT, 2 hours 28 minutes earlier.

Area forecast discussion, Aug 27, 2:23 PM CDT, 2 hours 28 minutes before

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Hazardous weather outlook, Aug 27, 2:58 PM CDT, 1 hour 53 minutes before

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In the hours before

Special weather statement, Aug 27, 4:43 PM CDT, 8 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 27, 2:22 PM CDT	Flood Watch	DMX	Butler, Cerro Gordo, Franklin, Hancock, Winnebago, Worth and 1 more	14 hr
Aug 27, 4:43 PM CDT	Special Weather Statement	DMX	Poweshiek	47 min
Aug 27, 6:16 PM CDT	Severe Thunderstorm Warning	DMX	Emmet	29 min
Aug 27, 6:21 PM CDT	Special Weather Statement	DMX	Grundy, Marshall	39 min
Aug 27, 6:45 PM CDT	Special Weather Statement	DMX	Cass	30 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.