Alert archive / South Dakota / Tornado Watches in 2026

Tornado Watch 213

May 17, 20264 states

The Storm Prediction Center issued this tornado watch at May 17, 2026, 1:42 PM CDT for 4 states. It was in force for 8 hr.

The area

The outline as issued.

The facts

Issued: May 17, 2026, 1:42 PM CDT (18:42 UTC)
Expired: May 17, 2026, 10:00 PM CDT
In force: 8 hr
Issued by: the Storm Prediction Center
Largest hail expected: 3 in
Strongest gust expected: 75 kt

All 55 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, Cottonwood County, MN, Jackson County, MN, Murray County, MN, Nobles County, MN, Pipestone County, MN, Rock County, MN, Antelope County, NE, Boyd County, NE, Burt County, NE, Cedar County, NE, Cuming County, NE, Dakota County, NE, Dixon County, NE, Garfield County, NE, Holt County, NE, Knox County, NE, Loup County, NE, Madison County, NE, Pierce County, NE, Rock County, NE, Stanton County, NE, Thurston County, NE, Wayne County, NE, Wheeler County, NE, Aurora County, SD, Bon Homme County, SD, Charles Mix County, SD, Clay County, SD, Davison County, SD, Douglas County, SD, Gregory County, SD, Hanson County, SD, Hutchinson County, SD, Lake County, SD, Lincoln County, SD, McCook County, SD, Miner County, SD, Minnehaha County, SD, Moody County, SD, Sanborn County, SD, Turner County, SD, Union County, SD, Yankton County, SD

The radar

The Sioux Falls radar (KFSD), 101 km from the middle of the area, began a volume at 18:45 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: 70%
One or more EF2 to EF5 tornadoes: 50%
Ten or more severe wind reports: 60%
One or more gusts of 65 knots or more: 50%
Ten or more severe hail reports: 60%
One or more hailstones of 2 inches or more: 50%
Six or more combined severe hail and wind reports: 95%

Warnings issued inside it

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

Issued	Product	Office	Counties	Lasted
May 17, 1:50 PM CDT	Severe Thunderstorm Warning	LBF	Boyd, Holt	40 min
May 17, 2:10 PM CDT	Severe Thunderstorm Warning	FSD	Charles Mix, Gregory	50 min
May 17, 2:15 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FSD	Aurora, Brule, Charles Mix, Douglas	45 min
May 17, 2:25 PM CDT	Severe Thunderstorm Warning Considerable damage threat	LBF	Boyd, Holt	37 min
May 17, 2:25 PM CDT	Severe Thunderstorm Warning	OAX	Knox	50 min
May 17, 2:49 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FSD	Bon Homme, Hutchinson, Yankton	41 min
May 17, 2:50 PM CDT	Tornado Warning	FSD	Bon Homme, Charles Mix, Hutchinson	40 min
May 17, 3:23 PM CDT	Tornado Warning	FSD	Hutchinson, Turner, Yankton	52 min
May 17, 3:28 PM CDT	Severe Thunderstorm Warning Destructive damage threat	FSD	Bon Homme, Clay, Hutchinson, Turner, Yankton	47 min
May 17, 3:35 PM CDT	Tornado Warning	FSD	Hutchinson, Turner	28 min
May 17, 3:59 PM CDT	Severe Thunderstorm Warning Destructive damage threat	FSD	Lincoln, Turner	46 min
May 17, 4:18 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FSD	Lyon	42 min
May 17, 4:27 PM CDT	Tornado Warning	FSD	Lyon	48 min
May 17, 4:56 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FSD	Lyon	49 min
May 17, 5:33 PM CDT	Tornado Warning	FSD	Nobles, Rock	42 min
May 17, 5:43 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FSD	Lyon, Osceola	62 min
May 17, 5:47 PM CDT	Severe Thunderstorm Warning	OAX	Antelope, Boone, Madison, Platte	43 min
May 17, 5:56 PM CDT	Severe Thunderstorm Warning	FSD	Lyon, O'Brien, Osceola, Sioux	27 min
May 17, 6:01 PM CDT	Severe Thunderstorm Warning Destructive damage threat	OAX	Madison, Platte, Stanton	44 min
May 17, 6:12 PM CDT	Tornado Warning	FSD	Jackson, Nobles	48 min
May 17, 6:15 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OAX	Madison, Stanton, Wayne	45 min
May 17, 6:23 PM CDT	Tornado Warning	OAX	Colfax, Platte, Stanton	25 min
May 17, 6:26 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OAX	Colfax, Cuming, Stanton	49 min
May 17, 6:30 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FSD	Dickinson, Osceola	75 min
May 17, 6:33 PM CDT	Severe Thunderstorm Warning	FSD	Plymouth, Sioux	57 min
May 17, 6:39 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OAX	Burt, Cuming, Dodge, Stanton, Thurston, Wayne	66 min
May 17, 6:57 PM CDT	Tornado Warning	FSD	Cottonwood, Jackson	48 min
May 17, 7:20 PM CDT	Severe Thunderstorm Warning	FSD	Plymouth, Sioux	28 min
May 17, 7:20 PM CDT	Severe Thunderstorm Warning	FSD	O'Brien, Osceola	26 min
May 17, 7:22 PM CDT	Tornado Warning	OAX	Thurston	11 min
May 17, 7:26 PM CDT	Tornado Warning	FSD	Woodbury	49 min
May 17, 7:27 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OAX	Harrison, Monona	48 min
May 17, 7:31 PM CDT	Tornado Warning	FSD	Jackson	14 min
May 17, 7:32 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FSD	Cherokee, Ida, Plymouth, Woodbury	58 min
May 17, 7:45 PM CDT	Tornado Warning	FSD	Cottonwood, Jackson	15 min
May 17, 7:47 PM CDT	Tornado Warning	FSD	Cherokee, Plymouth, Woodbury	43 min
May 17, 8:00 PM CDT	Severe Thunderstorm Warning	FSD	O'Brien, Osceola, Plymouth, Sioux	45 min
May 17, 8:00 PM CDT	Severe Thunderstorm Warning	OAX	Harrison, Monona	45 min
May 17, 8:03 PM CDT	Flash Flood Warning	FSD	Plymouth, Sioux	3 hr
May 17, 8:21 PM CDT	Severe Thunderstorm Warning Destructive damage threat	FSD	Buena Vista, Cherokee, Clay, Dickinson, Ida, O'Brien and 3 more	54 min
May 17, 8:26 PM CDT	Tornado Warning	FSD	Buena Vista, Cherokee, Clay, O'Brien	28 min
May 17, 8:42 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OAX	Harrison, Monona	33 min
May 17, 8:48 PM CDT	Tornado Warning	FSD	Clay, Dickinson	27 min
May 17, 8:54 PM CDT	Tornado Warning	FSD	Clay, Dickinson	51 min
May 17, 8:56 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OAX	Harrison, Monona, Pottawattamie, Shelby	64 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

Aberdeen, SD (KABR), launched 12:00Z, 6.7 hours before the alert went out and 212 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: 2103 m above ground
0-6 km bulk shear: 54 kt
0-1 km storm-relative helicity: 372 m²/s²
0-3 km storm-relative helicity: 379 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
May 17, 1:11 PM CDT	Mesoscale Discussion	SPC	Cherokee, Harrison, Ida, Lyon, Monona, O'Brien and 4 more	2 hr
May 17, 3:16 PM CDT	Tornado Watch	SPC	Fremont, Harrison, Mills, Montgomery, Page, Pottawattamie and 1 more	8 hr
May 17, 3:31 PM CDT	Mesoscale Discussion	SPC	Lyon, O'Brien, Osceola, Sioux	89 min
May 17, 5:45 PM CDT	Mesoscale Discussion	SPC	Buena Vista, Cerro Gordo, Clay, Emmet, Floyd, Franklin and 10 more	60 min
May 17, 6:12 PM CDT	Tornado Watch	SPC	Bremer, Butler, Cerro Gordo, Chickasaw, Emmet, Fayette and 13 more	6 hr
May 17, 6:53 PM CDT	Mesoscale Discussion	SPC	Cherokee, Crawford, Fremont, Harrison, Ida, Mills and 6 more	67 min
May 16, 7:01 PM CDT	Mesoscale Discussion	SPC	Adams, Buffalo, Clay, Dundy, Fillmore, Franklin and 14 more	119 min
May 16, 8:36 PM CDT	Mesoscale Discussion	SPC	Gage, Jefferson, Johnson, Thayer	114 min
May 16, 10:15 PM CDT	Mesoscale Discussion	SPC	Adams, Cass, Clay, Fillmore, Franklin, Gage and 13 more	2 hr
May 17, 12:33 AM CDT	Mesoscale Discussion	SPC	Gage, Johnson, Nemaha, Pawnee, Richardson	87 min
May 17, 3:08 AM CDT	Mesoscale Discussion	SPC	Boone, Buffalo, Custer, Dawson, Greeley, Hall and 7 more	97 min
May 17, 11:58 AM CDT	Mesoscale Discussion	SPC	Blaine, Boyd, Brown, Cherry, Garfield, Holt and 5 more	92 min
May 17, 2:45 PM CDT	Mesoscale Discussion	SPC	Adams, Boone, Buffalo, Butler, Cass, Clay and 33 more	60 min
May 17, 3:08 PM CDT	Mesoscale Discussion	SPC	Chase, Dundy	3 hr
May 17, 4:58 PM CDT	Severe Thunderstorm Watch	SPC	Dundy, Hitchcock	3 hr
May 17, 5:13 PM CDT	Mesoscale Discussion	SPC	Adams, Butler, Clay, Colfax, Dodge, Fillmore and 18 more	62 min

Nearby

Tornado Watches in South Dakota, 2026 Tornado Watches in Nebraska, 2026 Tornado Watches in Iowa, 2026 Every tornado watch in 2026

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.