Alert archive / Iowa / Severe Thunderstorm Warnings in 1991

Severe Thunderstorm Warning 64, NWS Quad Cities, IA

September 12, 1991Clinton County, Scott County, Iowa

NWS Quad Cities, IA issued this severe thunderstorm warning at Sep 12, 1991, 6:15 PM CDT for Clinton County, Scott County, Iowa. It was in force for 40 min. 2 reports 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
Sep 12, 1991, 6:15 PM CDT (23:15 UTC)
Expired
Sep 12, 1991, 6:55 PM CDT
In force
40 min
Issued by
NWS Quad Cities, IA
Area
Whole counties

Counties Clinton County, IA, Scott County, IA

What was reported inside it

TimeReportWhereRemark
Sep 12, 6:38 PM CDTThunderstorm Wind 60Clinton, IA
Sep 12, 6:45 PM CDTThunderstorm Wind 50Scott, 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, 11.3 hours before the alert went out and 421 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 1991-09-12Temperature 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 1991-09-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 21 square meters per square second.1939587897Sfc1 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
556 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
21 m²/s²
0-3 km storm-relative helicity
36 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 Quad Cities, IA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 12, 4:57 PM CDTSevere Thunderstorm WarningDVNJones33 min
Sep 12, 5:03 PM CDTSevere Thunderstorm WarningDVNCedar57 min
Sep 12, 5:07 PM CDTSevere Thunderstorm WarningDVNDelaware25 min
Sep 12, 5:18 PM CDTTornado WarningDVNJones27 min
Sep 12, 5:42 PM CDTSevere Thunderstorm WarningDVNJackson38 min
Sep 12, 6:15 PM CDTSevere Thunderstorm WarningDVNRock Island, Whiteside60 min

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.