Alert archive / Minnesota / Severe Thunderstorm Watches in 2012

Severe Thunderstorm Watch 248

May 5, 201214 counties in Iowa; 26 counties in Minnesota; Crawford County, Grant County, Wisconsin

The Storm Prediction Center issued this severe thunderstorm watch at May 5, 2012, 11:38 AM CDT for 14 counties in Iowa; 26 counties in Minnesota; Crawford County, Grant County, Wisconsin. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
May 5, 2012, 11:38 AM CDT (16:38 UTC)
Expired
May 5, 2012, 5:48 PM CDT
In force
6 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt
All 42 counties

Allamakee County, IA, Cerro Gordo County, IA, Chickasaw County, IA, Clayton County, IA, Emmet County, IA, Fayette County, IA, Floyd County, IA, Hancock County, IA, Howard County, IA, Kossuth County, IA, Mitchell County, IA, Winnebago County, IA, Winneshiek County, IA, Worth County, IA, Blue Earth County, MN, Brown County, MN, Carver County, MN, Dakota County, MN, Dodge County, MN, Faribault County, MN, Fillmore County, MN, Freeborn County, MN, Goodhue County, MN, Houston County, MN, Le Sueur County, MN, Martin County, MN, McLeod County, MN, Mower County, MN, Nicollet County, MN, Olmsted County, MN, Redwood County, MN, Renville County, MN, Rice County, MN, Scott County, MN, Sibley County, MN, Steele County, MN, Wabasha County, MN, Waseca County, MN, Watonwan County, MN, Winona County, MN, Crawford County, WI, Grant County, WI

The radar

The Minneapolis radar (KMPX), 81 km from the middle of the area, began a volume at 16:40 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
20%
One or more EF2 to EF5 tornadoes
5%
Ten or more severe wind reports
30%
One or more gusts of 65 knots or more
30%
Ten or more severe hail reports
30%
One or more hailstones of 2 inches or more
20%
Six or more combined severe hail and wind reports
70%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
May 5, 1:02 PM CDTSevere Thunderstorm WarningMPXBlue Earth, Brown, Nicollet, Sibley43 min
May 5, 1:36 PM CDTSevere Thunderstorm WarningMPXFaribault, Martin24 min
May 5, 1:50 PM CDTSevere Thunderstorm WarningMPXBlue Earth, Faribault, Freeborn, Waseca40 min
May 5, 1:57 PM CDTSevere Thunderstorm WarningDMXKossuth, Winnebago33 min
May 5, 2:28 PM CDTSevere Thunderstorm WarningDMXWinnebago32 min
May 5, 2:54 PM CDTSevere Thunderstorm WarningDMXCerro Gordo, Winnebago, Worth66 min
May 5, 3:31 PM CDTSevere Thunderstorm WarningARXFloyd, Mitchell59 min
May 5, 4:29 PM CDTSevere Thunderstorm WarningARXChickasaw, Floyd43 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

Minneapolis, MN (KMPX), launched 12:00Z, 4.6 hours before the alert went out and 80 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 2012-05-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCLEL10008507005003002001001 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 2012-05-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 174 square meters per square second.19395878Sfc1 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
480 m above ground
0-6 km bulk shear
57 kt
0-1 km storm-relative helicity
174 m²/s²
0-3 km storm-relative helicity
217 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.4

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 4, 8:30 PM CDTMesoscale DiscussionSPCAllamakee, Benton, Black Hawk, Bremer, Buchanan, Butler and 10 more60 min
May 4, 9:54 PM CDTMesoscale DiscussionSPCBuena Vista, Cherokee, Crawford, Harrison, Ida, Monona and 5 more96 min
May 5, 6:49 AM CDTSevere Thunderstorm WatchSPCCherokee, Lyon, O'Brien, Osceola, Plymouth, Sioux7 hr
May 5, 2:09 PM CDTMesoscale DiscussionSPCBuena Vista, Calhoun, Carroll, Cherokee, Clay, Crawford and 8 more96 min
May 5, 2:58 PM CDTMesoscale DiscussionSPCAllamakee, Dickinson, Emmet, Howard, Kossuth, Mitchell and 3 more62 min
May 5, 3:52 PM CDTMesoscale DiscussionSPCBuena Vista, Calhoun, Carroll, Cherokee, Clay, Crawford and 8 more83 min
May 5, 4:56 PM CDTMesoscale DiscussionSPCBremer, Buchanan, Clayton, Delaware, Dubuque, Fayette and 1 more94 min
May 5, 5:31 PM CDTTornado WatchSPCPlymouth, Sioux, Woodbury5 hr
May 5, 6:46 PM CDTSevere Thunderstorm WatchSPCLyon6 hr
May 5, 9:50 AM CDTMesoscale DiscussionSPCBrown, Cottonwood, Jackson, Lincoln, Lyon, Martin and 10 more55 min

Nearby

Severe Thunderstorm Watches in Minnesota, 2012Severe Thunderstorm Watches in Iowa, 2012Severe Thunderstorm Watches in Wisconsin, 2012Every severe thunderstorm watch in 2012

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.