Alert archive / Iowa / Severe Thunderstorm Warnings in 2013

Severe Thunderstorm Warning 121, NWS Quad Cities, IA

October 4, 2013Iowa County, Iowa

NWS Quad Cities, IA issued this severe thunderstorm warning at Oct 4, 2013, 8:27 AM CDT for Iowa County, Iowa. It was in force for 63 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
Oct 4, 2013, 8:27 AM CDT (13:27 UTC)
Expired
Oct 4, 2013, 9:30 AM CDT
In force
63 min
Issued by
NWS Quad Cities, IA
Area
Storm-based polygon
Hail
0.88 in
Wind
60.0 mph

County Iowa County, IA

The radar

The Quad Cities radar (KDVN), 124 km from the middle of the area, began a volume at 13:28 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 nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 1.5 hours before the alert went out and 130 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, Davenport, at 12:00Z on 2013-10-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1470 joules per kilogram.LCLLFCEL10008507005003002001001 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, Davenport, at 12:00Z on 2013-10-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 87 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
1470 J/kg
Mixed-layer CIN
-47 J/kg
Mixed-layer LCL
599 m above ground
0-6 km bulk shear
49 kt
0-1 km storm-relative helicity
87 m²/s²
0-3 km storm-relative helicity
162 m²/s²
Significant tornado parameter
1.2
Supercell composite
7.5

Open this sounding in Storm Lab

The office that day

Everything else NWS Quad Cities, IA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Oct 4, 3:39 AM CDTSpecial Weather StatementDVNBenton, Iowa81 min
Oct 4, 4:27 AM CDTSpecial Weather StatementDVNBenton, Iowa, Johnson, Linn93 min
Oct 4, 5:04 AM CDTSpecial Weather StatementDVNCedar, Johnson, Jones, Linn56 min
Oct 4, 5:55 AM CDTSpecial Weather StatementDVNCedar, Jones45 min
Oct 4, 6:37 AM CDTSpecial Weather StatementDVNCedar, Clinton, Jackson, Jones, Scott38 min
Oct 4, 7:53 AM CDTSpecial Weather StatementDVNBenton, Iowa, Linn52 min
Oct 4, 8:44 AM CDTSevere Thunderstorm WarningDVNBenton, Iowa, Johnson, Linn46 min
Oct 4, 9:33 AM CDTSpecial Weather StatementDVNLinn57 min
Oct 4, 9:55 AM CDTSpecial Weather StatementDVNIowa35 min
Oct 4, 5:59 PM CDTSpecial Weather StatementDVNDubuque31 min
Oct 4, 1:05 PM CDTSpecial Weather StatementDVNHenry55 min
Oct 4, 1:18 PM CDTSpecial Weather StatementDVNWhiteside12 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2013Every severe thunderstorm warning in 2013

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.