Alert archive / Iowa / Severe Thunderstorm Warnings in 2005

Severe Thunderstorm Warning 67, NWS Omaha, NE

April 21, 2005Pottawattamie County, Iowa

NWS Omaha, NE issued this severe thunderstorm warning at Apr 21, 2005, 4:24 AM CDT for Pottawattamie County, Iowa. It was in force for 36 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: Apr 21, 2005, 4:24 AM CDT (09:24 UTC)
Expired: Apr 21, 2005, 5:00 AM CDT
In force: 36 min
Issued by: NWS Omaha, NE
Area: Counties, with a storm outline in the text

County Pottawattamie County, IA

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 9.4 hours before the alert went out and 69 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: 954 J/kg
Mixed-layer CIN: -100 J/kg
Mixed-layer LCL: 886 m above ground
0-6 km bulk shear: 36 kt
0-1 km storm-relative helicity: 79 m²/s²
0-3 km storm-relative helicity: 265 m²/s²
Significant tornado parameter: 0.5
Supercell composite: 4.6

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 Omaha, NE wrote its last area forecast discussion before this severe thunderstorm warning went out at Apr 21, 3:20 AM CDT, 1 hour 4 minutes earlier.

Area forecast discussion, Apr 21, 3:20 AM CDT, 1 hour 4 minutes before

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Hazardous weather outlook, Apr 20, 5:23 PM CDT, 11 hours 1 minute before

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In the hours before

Local storm report, Apr 21, 12:26 AM CDT, 3 hours 58 minutes before

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Local storm report, Apr 21, 1:27 AM CDT, 2 hours 57 minutes before

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Local storm report, Apr 21, 2:02 AM CDT, 2 hours 22 minutes before

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Local storm report, Apr 21, 2:13 AM CDT, 2 hours 11 minutes before

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Local storm report, Apr 21, 2:32 AM CDT, 1 hour 52 minutes before

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Special weather statement, Apr 21, 3:30 AM CDT, 54 minutes before

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The office that day

Everything else NWS Omaha, NE issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 21, 12:05 AM CDT	Severe Thunderstorm Warning	OAX	Nemaha	40 min
Apr 21, 12:52 AM CDT	Severe Thunderstorm Warning	OAX	Gage	53 min
Apr 21, 1:07 AM CDT	Severe Thunderstorm Warning	OAX	Saline	40 min
Apr 21, 1:36 AM CDT	Severe Thunderstorm Warning	OAX	Seward	39 min
Apr 21, 2:13 AM CDT	Severe Thunderstorm Warning	OAX	Seward	32 min
Apr 21, 2:41 PM CDT	Severe Thunderstorm Warning	OAX	Boone	49 min
Apr 21, 3:00 PM CDT	Flash Flood Warning	OAX	Boone	3 hr
Apr 21, 3:06 PM CDT	Severe Thunderstorm Warning	OAX	Saline	39 min
Apr 21, 3:11 PM CDT	Severe Thunderstorm Warning	OAX	Platte	34 min
Apr 21, 3:13 PM CDT	Severe Thunderstorm Warning	OAX	Gage	32 min
Apr 21, 3:16 PM CDT	Severe Thunderstorm Warning	OAX	Jefferson	29 min
Apr 21, 3:23 PM CDT	Severe Thunderstorm Warning	OAX	Pawnee	37 min
Apr 21, 3:26 PM CDT	Flash Flood Warning	OAX	Madison, Platte	2 hr
Apr 21, 3:32 PM CDT	Severe Thunderstorm Warning	OAX	Colfax	46 min
Apr 21, 3:34 PM CDT	Tornado Warning	OAX	Johnson	26 min
Apr 21, 3:41 PM CDT	Severe Thunderstorm Warning	OAX	Saline	34 min
Apr 21, 3:43 PM CDT	Severe Thunderstorm Warning	OAX	Madison, Platte	47 min
Apr 21, 3:46 PM CDT	Severe Thunderstorm Warning	OAX	Gage	29 min
Apr 21, 3:52 PM CDT	Severe Thunderstorm Warning	OAX	Lancaster, Otoe	38 min
Apr 21, 3:58 PM CDT	Tornado Warning	OAX	Johnson	32 min
Apr 21, 4:14 PM CDT	Flash Flood Warning	OAX	Nemaha, Otoe	2 hr
Apr 21, 4:14 PM CDT	Severe Thunderstorm Warning	OAX	Gage	31 min
Apr 21, 4:14 PM CDT	Severe Thunderstorm Warning	OAX	Butler	46 min
Apr 21, 4:29 PM CDT	Severe Thunderstorm Warning	OAX	Johnson, Otoe	31 min
Apr 21, 4:30 PM CDT	Severe Thunderstorm Warning	OAX	Lancaster	30 min
Apr 21, 4:37 PM CDT	Severe Thunderstorm Warning	OAX	Cass	23 min
Apr 21, 4:47 PM CDT	Tornado Warning	OAX	Johnson, Nemaha, Otoe	28 min
Apr 21, 4:55 PM CDT	Severe Thunderstorm Warning	OAX	Sarpy, Saunders	35 min
Apr 21, 4:59 PM CDT	Severe Thunderstorm Warning	OAX	Lancaster	16 min
Apr 21, 5:00 PM CDT	Severe Thunderstorm Warning	OAX	Cass	45 min
Apr 21, 5:15 PM CDT	Tornado Warning	OAX	Otoe	30 min
Apr 21, 5:43 PM CDT	Severe Thunderstorm Warning	OAX	Otoe	32 min
Apr 21, 6:09 PM CDT	Flash Flood Warning	OAX	Otoe	96 min
Apr 21, 5:35 PM CDT	Severe Thunderstorm Warning	OAX	Fremont	40 min
Apr 21, 6:16 PM CDT	Flash Flood Warning	OAX	Fremont	119 min
Apr 21, 6:59 PM CDT	Severe Thunderstorm Warning	OAX	Fremont	31 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2005 Every severe thunderstorm warning in 2005

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.