Alert archive / Iowa / Severe Thunderstorm Warnings in 1991

Severe Thunderstorm Warning 69, NWS Des Moines, IA

May 17, 1991Wright County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at May 17, 1991, 1:54 PM CDT for Wright County, Iowa. It was in force for 36 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
May 17, 1991, 1:54 PM CDT (18:54 UTC)
Expired
May 17, 1991, 2:30 PM CDT
In force
36 min
Issued by
NWS Des Moines, IA
Area
Whole counties

County Wright County, IA

What was reported inside it

TimeReportWhereRemark
May 17, 2:18 PM CDTTornado F2Wright, IA

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.

The nearest sounding before it

Minneapolis, MN (KSTC), launched 12:00Z, 6.9 hours before the alert went out and 236 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-pSkew-T log-p diagram, Minneapolis, MN at 12:00Z on 1991-05-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 12:00Z on 1991-05-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -30 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
NaN m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
-30 m²/s²
0-3 km storm-relative helicity
49 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

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.

The office that day

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

IssuedProductOfficeCountiesLasted
May 17, 2:05 PM CDTTornado WarningDMXHamilton, Wright25 min
May 17, 2:35 PM CDTSevere Thunderstorm WarningDMXWright40 min
May 17, 3:01 PM CDTSevere Thunderstorm WarningDMXGreene44 min
May 17, 3:17 PM CDTSevere Thunderstorm WarningDMXBlack Hawk58 min
May 17, 3:53 PM CDTTornado WarningDMXJohnson37 min
May 17, 4:12 PM CDTTornado WarningDMXHamilton, Webster33 min
May 17, 4:16 PM CDTSevere Thunderstorm WarningDMXAppanoose, Davis44 min
May 17, 4:22 PM CDTSevere Thunderstorm WarningDMXFloyd38 min
May 17, 4:22 PM CDTSevere Thunderstorm WarningDMXButler, Grundy68 min
May 17, 4:55 PM CDTTornado WarningDMXWright50 min
May 17, 5:14 PM CDTSevere Thunderstorm WarningDMXBenton, Iowa46 min
May 17, 5:27 PM CDTSevere Thunderstorm WarningDMXVan Buren48 min
May 17, 5:36 PM CDTSevere Thunderstorm WarningDMXIowa, Johnson, Linn69 min
May 17, 5:45 PM CDTFlash Flood WarningDMXHamilton, Hardin, Humboldt, Webster, Wright4 hr

Nearby

Severe Thunderstorm Warnings in Iowa, 1991Every severe thunderstorm warning in 1991

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.