Alert archive / Iowa / Severe Thunderstorm Warnings in 2024

Severe Thunderstorm Warning 103, NWS Des Moines, IA

May 21, 2024Crawford County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at May 21, 2024, 1:38 PM CDT for Crawford County, Iowa. It was in force for 52 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 21, 2024, 1:38 PM CDT (18:38 UTC)
Expired: May 21, 2024, 2:30 PM CDT
In force: 52 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

County Crawford County, IA

The radar

The Omaha radar (KOAX), 114 km from the middle of the area, began a volume at 18:38 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
May 21, 1:14 PM CDT	Tornado Watch PDS	SPC	8 hr

The nearest sounding before it

Topeka, KS (KTOP), launched 12:00Z, 6.6 hours before the alert went out and 338 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: 1197 J/kg
Mixed-layer CIN: -325 J/kg
Mixed-layer LCL: 744 m above ground
0-6 km bulk shear: 48 kt
0-1 km storm-relative helicity: 562 m²/s²
0-3 km storm-relative helicity: 663 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.4

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 21, 12:35 PM CDT, 1 hour 3 minutes earlier.

Area forecast discussion, May 21, 12:35 PM CDT, 1 hour 3 minutes before

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Hazardous weather outlook, May 21, 3:44 AM CDT, 9 hours 54 minutes before

Hazardous Weather Outlook
National Weather Service Des Moines IA
344 AM CDT Tue May 21 2024

IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-
081>086-092>097-220845-
Emmet-Kossuth-Winnebago-Worth-Palo Alto-Hancock-Cerro Gordo-
Pocahontas-Humboldt-Wright-Franklin-Butler-Bremer-Sac-Calhoun-
Webster-Hamilton-Hardin-Grundy-Black Hawk-Crawford-Carroll-Greene-
Boone-Story-Marshall-Tama-Audubon-Guthrie-Dallas-Polk-Jasper-
Poweshiek-Cass-Adair-Madison-Warren-Marion-Mahaska-Adams-Union-
Clarke-Lucas-Monroe-Wapello-Taylor-Ringgold-Decatur-Wayne-
Appanoose-Davis-
344 AM CDT Tue May 21 2024

This Hazardous Weather Outlook is for portions of central Iowa.

.DAY ONE...Today and tonight

Thunderstorms from overnight are expected to linger through the
morning with damaging winds and flash flooding the primary
threats. Additional storms are expected to develop during the
afternoon with tornadoes, damaging winds, flash flooding, and
large hail all possible. The worst of the storms will be primarily
after 3pm. Winds could gust over 40mph at times as storms exit.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

Additional thunderstorm chances return at times Friday and
through the weekend. The severe weather potential for these days
will be better determined in the coming days.

.SPOTTER INFORMATION STATEMENT...

Spotters will likely be needed at times today.

In the hours before

Local storm report, May 21, 12:28 PM CDT, 1 hour 10 minutes before

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Local storm report, May 21, 12:54 PM CDT, 44 minutes before

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Local storm report, May 21, 12:59 PM CDT, 39 minutes before

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Local storm report, May 21, 1:35 PM CDT, 3 minutes before

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Local storm report, May 21, 1:36 PM CDT, 2 minutes before

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Local storm report, May 21, 1:37 PM CDT, 1 minute before

Preliminary Local Storm Report
National Weather Service Des Moines IA
137 PM CDT Tue May 21 2024

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0127 PM     Flood            4 NE Algona             43.11N 94.18W
05/21/2024                   Kossuth            IA   Emergency Mngr

            Approximately 20 secondary roads closed due
            to water over the road in the county.

&&

JAZ

The office that day

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

Issued	Product	Office	Counties	Lasted
May 20, 8:25 PM CDT	Severe Thunderstorm Warning Considerable damage threat	DMX	Palo Alto, Pocahontas	50 min
May 20, 8:48 PM CDT	Severe Thunderstorm Warning	DMX	Hancock, Kossuth, Winnebago	42 min
May 20, 9:12 PM CDT	River Flood Watch	DMX	Black Hawk	24 hr
May 20, 9:13 PM CDT	Severe Thunderstorm Warning Considerable damage threat	DMX	Humboldt, Kossuth, Palo Alto, Pocahontas	37 min
May 20, 9:30 PM CDT	Severe Thunderstorm Warning	DMX	Hancock, Winnebago, Worth	22 min
May 20, 10:20 PM CDT	Special Weather Statement	DMX	Hancock	25 min
May 20, 10:35 PM CDT	Severe Thunderstorm Warning	DMX	Kossuth	25 min
May 20, 10:40 PM CDT	Special Weather Statement	DMX	Palo Alto, Pocahontas	35 min
May 20, 11:02 PM CDT	Severe Thunderstorm Warning	DMX	Palo Alto, Pocahontas	28 min
May 20, 11:16 PM CDT	Flash Flood Warning	DMX	Hancock, Kossuth, Winnebago	6 hr
May 20, 11:30 PM CDT	Special Weather Statement	DMX	Carroll	30 min
May 20, 11:34 PM CDT	Special Weather Statement	DMX	Guthrie	26 min
May 20, 11:58 PM CDT	Severe Thunderstorm Warning	DMX	Boone, Calhoun, Carroll, Dallas, Greene, Guthrie and 2 more	36 min
May 21, 12:06 AM CDT	Special Weather Statement	DMX	Pocahontas	24 min
May 21, 12:10 AM CDT	Special Weather Statement	DMX	Hancock	35 min
May 21, 1:09 AM CDT	Severe Thunderstorm Warning	DMX	Audubon, Carroll, Crawford	66 min
May 21, 1:20 AM CDT	Severe Thunderstorm Warning	DMX	Jasper, Polk	40 min
May 21, 2:15 AM CDT	Special Weather Statement	DMX	Audubon, Guthrie	60 min
May 21, 2:32 AM CDT	Special Weather Statement	DMX	Black Hawk, Tama	28 min
May 21, 2:38 AM CDT	Severe Thunderstorm Warning	DMX	Black Hawk, Butler, Grundy, Hardin	37 min
May 21, 2:56 AM CDT	Severe Thunderstorm Warning	DMX	Black Hawk, Bremer, Butler	49 min
May 21, 3:09 AM CDT	Flash Flood Warning	DMX	Butler, Franklin, Grundy, Hardin, Wright	8 hr
May 21, 3:22 AM CDT	Severe Thunderstorm Warning	DMX	Carroll, Crawford, Sac	38 min
May 21, 3:26 AM CDT	Flash Flood Warning	DMX	Adair, Audubon, Cass, Guthrie	8 hr
May 21, 4:12 AM CDT	Special Weather Statement	DMX	Polk	33 min
May 21, 4:22 AM CDT	Flash Flood Warning	DMX	Boone, Dallas, Greene, Guthrie, Jasper, Marshall and 2 more	7 hr
May 21, 5:09 AM CDT	Areal Flood Warning	DMX	Hancock, Kossuth, Winnebago	14 hr
May 21, 5:25 AM CDT	Severe Thunderstorm Warning	DMX	Poweshiek, Tama	50 min
May 21, 5:51 AM CDT	Severe Thunderstorm Warning	DMX	Jasper, Poweshiek, Tama	39 min
May 21, 6:18 AM CDT	Severe Thunderstorm Warning	DMX	Poweshiek, Tama	42 min
May 21, 6:26 AM CDT	Flash Flood Warning	DMX	Jasper, Marshall, Poweshiek, Tama	5 hr
May 21, 6:28 AM CDT	Severe Thunderstorm Warning Considerable damage threat	DMX	Carroll, Crawford, Sac	47 min
May 21, 6:51 AM CDT	Severe Thunderstorm Warning	DMX	Audubon, Carroll, Cass, Crawford, Guthrie	54 min
May 21, 7:07 AM CDT	Severe Thunderstorm Warning Considerable damage threat	DMX	Cass	23 min
May 21, 7:24 AM CDT	Tornado Warning	DMX	Adair, Cass	36 min
May 21, 7:29 AM CDT	Severe Thunderstorm Warning Considerable damage threat	DMX	Adair, Audubon, Cass, Guthrie	46 min
May 21, 7:35 AM CDT	Severe Thunderstorm Warning	DMX	Adair, Adams, Cass, Taylor	40 min
May 21, 8:05 AM CDT	Severe Thunderstorm Warning	DMX	Adair, Dallas, Guthrie, Madison	55 min
May 21, 8:41 AM CDT	Severe Thunderstorm Warning Considerable damage threat	DMX	Dallas, Madison, Polk, Warren	64 min
May 21, 8:57 AM CDT	Flash Flood Warning	DMX	Black Hawk, Bremer, Grundy, Hardin, Marshall, Tama	2 hr
May 21, 9:26 AM CDT	Severe Thunderstorm Warning	DMX	Jasper, Mahaska, Marion, Marshall, Polk, Poweshiek and 2 more	64 min
May 21, 10:09 AM CDT	River Flood Warning	DMX	Cass	15 hr
May 21, 11:14 AM CDT	River Flood Watch	DMX	Polk	4 days
May 21, 11:14 AM CDT	River Flood Watch	DMX	Webster	9 hr
May 21, 11:14 AM CDT	River Flood Watch	DMX	Polk	5 days
May 21, 11:14 AM CDT	River Flood Watch	DMX	Dallas, Greene	4 days
May 21, 11:14 AM CDT	River Flood Watch	DMX	Boone, Hamilton, Webster	47 hr
May 21, 11:14 AM CDT	River Flood Warning	DMX	Tama	8 days
May 21, 11:14 AM CDT	Severe Thunderstorm Warning	DMX	Jasper, Mahaska, Marion, Poweshiek	46 min
May 21, 11:16 AM CDT	Areal Flood Warning	DMX	Black Hawk, Bremer, Butler, Franklin, Grundy, Hardin and 6 more	24 hr
May 21, 11:54 AM CDT	Severe Thunderstorm Warning Considerable damage threat	DMX	Poweshiek	21 min
May 21, 2:18 PM CDT	Severe Thunderstorm Warning	DMX	Sac	29 min
May 21, 2:28 PM CDT	Severe Thunderstorm Warning	DMX	Adams, Audubon, Cass	62 min
May 21, 2:30 PM CDT	Severe Thunderstorm Warning	DMX	Audubon, Calhoun, Carroll, Crawford, Sac	45 min
May 21, 2:52 PM CDT	Tornado Warning	DMX	Adams, Cass	18 min
May 21, 2:55 PM CDT	Tornado Warning	DMX	Adair, Adams, Cass, Union	50 min
May 21, 2:57 PM CDT	Flash Flood Warning	DMX	Adair, Audubon, Carroll, Cass, Crawford, Greene and 1 more	6 hr
May 21, 3:07 PM CDT	Tornado Warning	DMX	Adair, Adams, Madison, Taylor, Union	53 min
May 21, 3:11 PM CDT	Severe Thunderstorm Warning Considerable damage threat	DMX	Audubon, Boone, Calhoun, Carroll, Greene, Guthrie and 1 more	49 min
May 21, 3:13 PM CDT	Tornado Warning	DMX	Audubon, Cass, Greene, Guthrie	22 min
May 21, 3:20 PM CDT	River Flood Warning	DMX	Polk	7 hr
May 21, 3:26 PM CDT	River Flood Warning	DMX	Polk	4 days
May 21, 3:26 PM CDT	River Flood Warning	DMX	Polk	4 days
May 21, 3:26 PM CDT	Tornado Warning Tornado observed	DMX	Adair, Adams, Madison, Union	49 min
May 21, 3:31 PM CDT	Severe Thunderstorm Warning Destructive damage threat	DMX	Boone, Greene, Hamilton, Webster, Wright	44 min
May 21, 3:33 PM CDT	Tornado Warning	DMX	Ringgold, Taylor, Union	42 min
May 21, 3:35 PM CDT	Tornado Warning Tornado observedConsiderable damage threat	DMX	Adair, Dallas, Guthrie, Madison	40 min
May 21, 3:40 PM CDT	Tornado Warning Tornado observed	DMX	Adair, Adams, Dallas, Madison, Ringgold, Union	50 min
May 21, 3:55 PM CDT	Tornado Warning	DMX	Clarke, Madison, Ringgold, Union, Warren	50 min
May 21, 3:58 PM CDT	Tornado Warning	DMX	Clarke, Decatur, Lucas, Ringgold, Union, Warren	47 min
May 21, 4:01 PM CDT	Severe Thunderstorm Warning	DMX	Boone, Greene, Guthrie, Hamilton, Webster	44 min
May 21, 4:03 PM CDT	Tornado Warning	DMX	Boone, Hamilton, Webster	42 min
May 21, 4:11 PM CDT	Severe Thunderstorm Warning	DMX	Boone, Clarke, Dallas, Decatur, Lucas, Madison and 4 more	64 min
May 21, 4:11 PM CDT	Severe Thunderstorm Warning	DMX	Hancock, Kossuth, Winnebago, Worth	49 min
May 21, 4:15 PM CDT	Severe Thunderstorm Warning	DMX	Cerro Gordo, Franklin, Hancock, Worth, Wright	45 min
May 21, 4:19 PM CDT	Tornado Warning	DMX	Boone, Dallas, Polk, Story	41 min
May 21, 4:25 PM CDT	Severe Thunderstorm Warning	DMX	Boone, Franklin, Grundy, Hamilton, Hardin, Marshall and 2 more	50 min
May 21, 4:30 PM CDT	Tornado Warning	DMX	Jasper, Madison, Polk, Warren	45 min
May 21, 4:43 PM CDT	Severe Thunderstorm Warning	DMX	Grundy, Hardin, Jasper, Marion, Marshall, Polk and 2 more	47 min
May 21, 4:46 PM CDT	Tornado Warning	DMX	Franklin, Grundy, Hamilton, Hardin	17 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2024 Every severe thunderstorm warning in 2024

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.