Alert archive / Iowa / Severe Thunderstorm Watches in 2014

Severe Thunderstorm Watch 72

April 12, 201410 counties in Illinois; 61 counties in Iowa; 29 counties in Wisconsin

The Storm Prediction Center issued this severe thunderstorm watch at Apr 12, 2014, 9:38 PM CDT for 10 counties in Illinois; 61 counties in Iowa; 29 counties in Wisconsin. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Apr 12, 2014, 9:38 PM CDT (02:38 UTC)
Expired
Apr 13, 2014, 3:47 AM CDT
In force
6 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
65 kt
All 100 counties

Adair County, IA, Allamakee County, IA, Audubon County, IA, Benton County, IA, Black Hawk County, IA, Boone County, IA, Bremer County, IA, Buchanan County, IA, Butler County, IA, Calhoun County, IA, Carroll County, IA, Cass County, IA, Cedar County, IA, Cerro Gordo County, IA, Chickasaw County, IA, Clayton County, IA, Clinton County, IA, Dallas County, IA, Delaware County, IA, Des Moines County, IA, Dubuque County, IA, Fayette County, IA, Floyd County, IA, Franklin County, IA, Greene County, IA, Grundy County, IA, Guthrie County, IA, Hamilton County, IA, Hardin County, IA, Henry County, IA, Howard County, IA, Humboldt County, IA, Iowa County, IA, Jackson County, IA, Jasper County, IA, Jefferson County, IA, Johnson County, IA, Jones County, IA, Keokuk County, IA, Lee County, IA, Linn County, IA, Louisa County, IA, Madison County, IA, Mahaska County, IA, Marion County, IA, Marshall County, IA, Mitchell County, IA, Muscatine County, IA, Pocahontas County, IA, Polk County, IA, Poweshiek County, IA, Sac County, IA, Scott County, IA, Story County, IA, Tama County, IA, Van Buren County, IA, Warren County, IA, Washington County, IA, Webster County, IA, Winneshiek County, IA, Wright County, IA, Boone County, IL, Carroll County, IL, Jo Daviess County, IL, Lake County, IL, McHenry County, IL, Ogle County, IL, Rock Island County, IL, Stephenson County, IL, Whiteside County, IL, Winnebago County, IL, Adams County, WI, Calumet County, WI, Columbia County, WI, Crawford County, WI, Dane County, WI, Dodge County, WI, Fond du Lac County, WI, Grant County, WI, Green County, WI, Green Lake County, WI, Iowa County, WI, Jefferson County, WI, Juneau County, WI, Kenosha County, WI, Lafayette County, WI, Manitowoc County, WI, Marquette County, WI, Milwaukee County, WI, Ozaukee County, WI, Racine County, WI, Richland County, WI, Rock County, WI, Sauk County, WI, Sheboygan County, WI, Vernon County, WI, Walworth County, WI, Washington County, WI, Waukesha County, WI, Winnebago County, WI

The radar

The Des Moines radar (KDMX), 154 km from the middle of the area, began a volume at 02:41 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.

What SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
5%
One or more EF2 to EF5 tornadoes
2%
Ten or more severe wind reports
40%
One or more gusts of 65 knots or more
30%
Ten or more severe hail reports
70%
One or more hailstones of 2 inches or more
40%
Six or more combined severe hail and wind reports
90%

Warnings issued inside it

24 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Apr 12, 9:44 PM CDTSevere Thunderstorm WarningARXAllamakee, Clayton31 min
Apr 12, 9:44 PM CDTSevere Thunderstorm WarningDMXAdair, Adams, Madison, Union46 min
Apr 12, 9:49 PM CDTSevere Thunderstorm WarningMKXColumbia, Dane, Sauk41 min
Apr 12, 10:05 PM CDTSevere Thunderstorm WarningMKXOzaukee, Washington55 min
Apr 12, 10:06 PM CDTSevere Thunderstorm WarningDMXHamilton, Hardin24 min
Apr 12, 10:07 PM CDTSevere Thunderstorm WarningDMXClarke, Madison, Union, Warren38 min
Apr 12, 10:09 PM CDTSevere Thunderstorm WarningDMXBlack Hawk, Bremer, Tama36 min
Apr 12, 10:15 PM CDTSevere Thunderstorm WarningDVNBenton, Buchanan60 min
Apr 12, 10:20 PM CDTSevere Thunderstorm WarningDMXJasper, Marshall, Poweshiek, Tama25 min
Apr 12, 10:22 PM CDTSevere Thunderstorm WarningMKXSauk38 min
Apr 12, 10:26 PM CDTSevere Thunderstorm WarningDMXClarke, Madison, Union, Warren34 min
Apr 12, 10:29 PM CDTSevere Thunderstorm WarningMKXColumbia46 min
Apr 12, 10:44 PM CDTSevere Thunderstorm WarningDMXClarke, Lucas, Marion, Monroe, Warren46 min
Apr 12, 10:44 PM CDTSevere Thunderstorm WarningDMXJasper, Marshall, Poweshiek, Tama31 min
Apr 12, 11:10 PM CDTFlash Flood WarningMKXColumbia, Iowa, Sauk3 hr
Apr 12, 11:11 PM CDTSevere Thunderstorm WarningDMXPoweshiek, Tama34 min
Apr 12, 11:20 PM CDTSevere Thunderstorm WarningDMXAppanoose, Davis, Jasper, Mahaska, Marion, Monroe and 2 more55 min
Apr 12, 11:35 PM CDTSevere Thunderstorm WarningDVNBenton, Iowa, Johnson, Keokuk, Linn, Washington55 min
Apr 12, 11:50 PM CDTSevere Thunderstorm WarningDVNHenry, Jefferson, Keokuk, Van Buren, Washington55 min
Apr 13, 12:02 AM CDTSevere Thunderstorm WarningMKXColumbia, Dane, Dodge43 min
Apr 13, 12:27 AM CDTSevere Thunderstorm WarningDVNCedar, Johnson, Jones, Linn, Louisa, Muscatine and 1 more63 min
Apr 13, 1:30 AM CDTSevere Thunderstorm WarningDVNCarroll, Rock Island, Whiteside45 min
Apr 13, 2:28 AM CDTSevere Thunderstorm WarningLOTBoone, McHenry, Winnebago47 min
Apr 13, 2:52 AM CDTSevere Thunderstorm WarningDMXAdair, Cass, Guthrie38 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 2.6 hours before the alert went out and 178 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 00:00Z on 2014-04-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 661 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 00:00Z on 2014-04-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 34 square meters per square second.193958Sfc1 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
661 J/kg
Mixed-layer CIN
-152 J/kg
Mixed-layer LCL
1978 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
34 m²/s²
0-3 km storm-relative helicity
80 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 12, 9:08 PM CDTMesoscale DiscussionSPCBoone, Carroll, Jo Daviess, McHenry, Ogle, Stephenson and 1 more67 min
Apr 12, 11:26 PM CDTMesoscale DiscussionSPCBoone, Carroll, Jo Daviess, McHenry, Ogle, Rock Island and 3 more64 min
Apr 13, 1:37 AM CDTMesoscale DiscussionSPCBoone, Carroll, DeKalb, Jo Daviess, Lee, McHenry and 5 more83 min
Apr 13, 7:41 AM CDTMesoscale DiscussionSPCAdams, Brown, Calhoun, Greene, Hancock, Henderson and 5 more2 hr
Apr 12, 9:12 PM CDTMesoscale DiscussionSPCDecatur, Page, Ringgold, Taylor63 min
Apr 13, 1:16 PM CDTMesoscale DiscussionSPCBuena Vista, Carroll, Cherokee, Crawford, Harrison, Ida and 7 more6 hr

Nearby

Severe Thunderstorm Watches in Iowa, 2014Severe Thunderstorm Watches in Wisconsin, 2014Severe Thunderstorm Watches in Illinois, 2014Every severe thunderstorm watch in 2014

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.