Alert archive / Iowa / Mesoscale Discussions in 2022

Mesoscale Discussion 464

April 12, 202220 counties in Iowa; 6 counties in Minnesota; 11 counties in Wisconsin

The Storm Prediction Center issued this mesoscale discussion at Apr 12, 2022, 7:14 PM CDT for 20 counties in Iowa; 6 counties in Minnesota; 11 counties in Wisconsin. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Apr 12, 2022, 7:14 PM CDT (00:14 UTC)
Expired
Apr 12, 2022, 9:15 PM CDT
In force
2 hr
Issued by
the Storm Prediction Center
Concerning
Severe potential...watch likely
Chance of a watch
80%
All 37 counties

Allamakee County, IA, Benton County, IA, Black Hawk County, IA, Bremer County, IA, Buchanan County, IA, Butler County, IA, Cerro Gordo County, IA, Chickasaw County, IA, Clayton County, IA, Delaware County, IA, Fayette County, IA, Floyd County, IA, Franklin County, IA, Grundy County, IA, Hardin County, IA, Howard County, IA, Marshall County, IA, Mitchell County, IA, Tama County, IA, Winneshiek County, IA, Fillmore County, MN, Houston County, MN, Mower County, MN, Olmsted County, MN, Wabasha County, MN, Winona County, MN, Buffalo County, WI, Crawford County, WI, Eau Claire County, WI, Jackson County, WI, Juneau County, WI, La Crosse County, WI, Monroe County, WI, Pepin County, WI, Richland County, WI, Trempealeau County, WI, Vernon County, WI

The radar

The La Crosse radar (KARX), 121 km from the middle of the area, began a volume at 00:14 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 0.2 hours before the alert went out and 204 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 00:00Z on 2022-04-13Temperature 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 00:00Z on 2022-04-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 710 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
992 m above ground
0-6 km bulk shear
62 kt
0-1 km storm-relative helicity
710 m²/s²
0-3 km storm-relative helicity
827 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 12, 7:54 PM CDTTornado WatchSPCChickasaw, Floyd, Howard, Mitchell, Winneshiek4 hr
Apr 12, 9:38 PM CDTMesoscale DiscussionSPCAdair, Adams, Appanoose, Benton, Black Hawk, Boone and 31 more2 hr
Apr 12, 10:26 PM CDTMesoscale DiscussionSPCAllamakee, Winneshiek64 min
Apr 12, 10:45 PM CDTSevere Thunderstorm WatchSPCAllamakee, Fayette3 hr

Nearby

Mesoscale Discussions in Iowa, 2022Mesoscale Discussions in Wisconsin, 2022Mesoscale Discussions in Minnesota, 2022Every mesoscale discussion in 2022

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.