Alert archive / Iowa / Tornado Watches in 2022

Tornado Watch 111

April 12, 202212 counties in Iowa; 9 counties in Nebraska; 7 counties in South Dakota

The Storm Prediction Center issued this tornado watch at Apr 12, 2022, 3:41 PM CDT for 12 counties in Iowa; 9 counties in Nebraska; 7 counties in South Dakota. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued: Apr 12, 2022, 3:41 PM CDT (20:41 UTC)
Expired: Apr 12, 2022, 10:00 PM CDT
In force: 6 hr
Issued by: the Storm Prediction Center
Largest hail expected: 2.5 in
Strongest gust expected: 65 kt

All 28 counties

Buena Vista County, IA, Cherokee County, IA, Clay County, IA, Dickinson County, IA, Ida County, IA, Lyon County, IA, Monona County, IA, O'Brien County, IA, Osceola County, IA, Plymouth County, IA, Sioux County, IA, Woodbury County, IA, Burt County, NE, Cedar County, NE, Cuming County, NE, Dakota County, NE, Dixon County, NE, Knox County, NE, Pierce County, NE, Thurston County, NE, Wayne County, NE, Bon Homme County, SD, Clay County, SD, Hutchinson County, SD, Lincoln County, SD, Turner County, SD, Union County, SD, Yankton County, SD

The radar

The Sioux Falls radar (KFSD), 99 km from the middle of the area, began a volume at 20:41 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: 60%
One or more EF2 to EF5 tornadoes: 40%
Ten or more severe wind reports: 60%
One or more gusts of 65 knots or more: 50%
Ten or more severe hail reports: 70%
One or more hailstones of 2 inches or more: 70%
Six or more combined severe hail and wind reports: 95%

Warnings issued inside it

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

Issued	Product	Office	Counties	Lasted
Apr 12, 5:22 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FSD	Cherokee, Ida, Plymouth, Woodbury	38 min
Apr 12, 5:29 PM CDT	Severe Thunderstorm Warning	FSD	Aurora, Charles Mix, Davison, Douglas, Hanson, Hutchinson	46 min
Apr 12, 5:30 PM CDT	Severe Thunderstorm Warning	OAX	Monona	17 min
Apr 12, 5:33 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FSD	Buena Vista, Cherokee, Clay, Dickinson, Ida, O'Brien	42 min
Apr 12, 5:45 PM CDT	Severe Thunderstorm Warning	FSD	Ida	31 min
Apr 12, 5:48 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FSD	Charles Mix, Douglas, Hanson, Hutchinson	42 min
Apr 12, 5:51 PM CDT	Severe Thunderstorm Warning	FSD	McCook, Minnehaha, Moody, Turner	39 min
Apr 12, 5:54 PM CDT	Severe Thunderstorm Warning	FSD	Lyon	33 min
Apr 12, 6:08 PM CDT	Severe Thunderstorm Warning	FSD	Clay, Dickinson	52 min
Apr 12, 6:10 PM CDT	Severe Thunderstorm Warning	FSD	Davison, Hanson, Hutchinson, McCook, Miner	35 min
Apr 12, 6:21 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FSD	Hanson, Hutchinson, McCook, Turner	39 min
Apr 12, 6:31 PM CDT	Severe Thunderstorm Warning	FSD	Buena Vista, Clay	13 min
Apr 12, 6:36 PM CDT	Tornado Warning Tornado observed	FSD	Hutchinson, McCook, Turner	24 min
Apr 12, 6:38 PM CDT	Severe Thunderstorm Warning	OAX	Colfax, Cuming, Dodge	22 min
Apr 12, 6:41 PM CDT	Severe Thunderstorm Warning	OAX	Harrison, Monona	19 min
Apr 12, 6:51 PM CDT	Severe Thunderstorm Warning	OAX	Harrison, Monona	39 min
Apr 12, 6:57 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FSD	Hutchinson, McCook, Minnehaha, Turner	33 min
Apr 12, 7:02 PM CDT	Severe Thunderstorm Warning	OAX	Monona	43 min
Apr 12, 7:23 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OAX	Harrison, Monona, Pottawattamie	52 min
Apr 12, 7:37 PM CDT	Severe Thunderstorm Warning	FSD	Buena Vista, Cherokee, Ida, Woodbury	68 min
Apr 12, 8:04 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OAX	Harrison, Monona, Pottawattamie, Shelby	56 min
Apr 12, 8:13 PM CDT	Severe Thunderstorm Warning	FSD	Clay, Dickinson	16 min
Apr 12, 8:53 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OAX	Harrison, Monona, Pottawattamie, Shelby	22 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

Omaha, NE (KOAX), launched 12:00Z, 8.7 hours before the alert went out and 159 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1473 m above ground
0-6 km bulk shear: 56 kt
0-1 km storm-relative helicity: 597 m²/s²
0-3 km storm-relative helicity: 872 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 12, 2:48 PM CDT	Mesoscale Discussion	SPC	Cherokee, Crawford, Harrison, Ida, Lyon, Monona and 6 more	87 min
Apr 12, 5:11 PM CDT	Tornado Watch	SPC	Calhoun, Carroll, Cerro Gordo, Crawford, Emmet, Franklin and 12 more	7 hr
Apr 12, 5:45 PM CDT	Mesoscale Discussion	SPC	Boone, Buena Vista, Calhoun, Cherokee, Clay, Hamilton and 9 more	2 hr
Apr 12, 6:26 PM CDT	Mesoscale Discussion	SPC	Harrison, Mills, Pottawattamie, Shelby	2 hr
Apr 12, 6:46 PM CDT	Severe Thunderstorm Watch	SPC	Adair, Adams, Audubon, Boone, Cass, Dallas and 15 more	6 hr
Apr 12, 8:48 AM CDT	Mesoscale Discussion	SPC	Harding	4 hr
Apr 12, 6:00 PM CDT	Severe Thunderstorm Watch	SPC	Brookings, Hanson, Kingsbury, Lake, McCook, Miner and 2 more	5 hr

Nearby

Tornado Watches in Iowa, 2022 Tornado Watches in Nebraska, 2022 Tornado Watches in South Dakota, 2022 Every tornado watch 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.