Alert archive / Iowa / Severe Thunderstorm Warnings in 1993

Severe Thunderstorm Warning 157, NWS Des Moines, IA

July 17, 1993Linn County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Jul 17, 1993, 5:00 PM CDT for Linn County, Iowa. It was in force for 30 min.

The area

The counties it named.

The facts

Issued: Jul 17, 1993, 5:00 PM CDT (22:00 UTC)
Expired: Jul 17, 1993, 5:30 PM CDT
In force: 30 min
Issued by: NWS Des Moines, IA
Area: Whole counties

County Linn County, IA

The nearest sounding before it

Minneapolis, MN (KSTC), launched 12:00Z, 10.0 hours before the alert went out and 348 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: 602 J/kg
Mixed-layer CIN: -112 J/kg
Mixed-layer LCL: 619 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: 115 m²/s²
0-3 km storm-relative helicity: 140 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.8

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

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.

In the hours before

Special weather statement, Jul 17, 3:20 PM CDT, 1 hour 40 minutes before

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Special weather statement, Jul 17, 3:26 PM CDT, 1 hour 34 minutes before

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Special weather statement, Jul 17, 4:46 PM CDT, 14 minutes before

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Special weather statement, Jul 17, 4:47 PM CDT, 13 minutes before

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Special weather statement, Jul 17, 4:48 PM CDT, 12 minutes before

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      <h1 id="headline">This service is currently unavailable.</h1>
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Special weather statement, Jul 17, 5:00 PM CDT, 0 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, 5:44 AM CDT	Flash Flood Warning	DMX	Story	3 hr
Jul 17, 6:35 AM CDT	Flash Flood Warning	DMX	Hardin, Marshall	3 hr
Jul 17, 9:20 AM CDT	Flash Flood Warning	DMX	Polk	3 hr
Jul 17, 2:00 PM CDT	Flash Flood Warning	DMX	Marshall	4 hr
Jul 17, 3:42 PM CDT	Severe Thunderstorm Warning	DMX	Benton	33 min
Jul 17, 6:03 PM CDT	Flash Flood Warning	DMX	Buchanan	3 hr

Nearby

Severe Thunderstorm Warnings in Iowa, 1993 Every severe thunderstorm warning in 1993

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.