Alert archive / Iowa / Tornado Watches in 2026

Tornado Watch 225

May 18, 202627 counties in Iowa; Atchison County, Doniphan County, Kansas; 12 counties in Missouri

The Storm Prediction Center issued this tornado watch at May 18, 2026, 3:49 PM CDT for 27 counties in Iowa; Atchison County, Doniphan County, Kansas; 12 counties in Missouri. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued: May 18, 2026, 3:49 PM CDT (20:49 UTC)
Expired: May 18, 2026, 10:00 PM CDT
In force: 6 hr
Issued by: the Storm Prediction Center
Largest hail expected: 2 in
Strongest gust expected: 70 kt

All 41 counties

Adair County, IA, Adams County, IA, Appanoose County, IA, Cass County, IA, Clarke County, IA, Davis County, IA, Decatur County, IA, Fremont County, IA, Jasper County, IA, Lucas County, IA, Madison County, IA, Mahaska County, IA, Marion County, IA, Marshall County, IA, Mills County, IA, Monroe County, IA, Montgomery County, IA, Page County, IA, Polk County, IA, Poweshiek County, IA, Ringgold County, IA, Tama County, IA, Taylor County, IA, Union County, IA, Wapello County, IA, Warren County, IA, Wayne County, IA, Atchison County, KS, Doniphan County, KS, Andrew County, MO, Atchison County, MO, Buchanan County, MO, Daviess County, MO, DeKalb County, MO, Gentry County, MO, Grundy County, MO, Harrison County, MO, Holt County, MO, Mercer County, MO, Nodaway County, MO, Worth County, MO

The radar

The Omaha radar (KOAX), 141 km from the middle of the area, began a volume at 20:54 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: 60%
Ten or more severe wind reports: 80%
One or more gusts of 65 knots or more: 70%
Ten or more severe hail reports: 60%
One or more hailstones of 2 inches or more: 60%
Six or more combined severe hail and wind reports: 95%

Warnings issued inside it

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

Issued	Product	Office	Counties	Lasted
May 18, 4:02 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OAX	Fremont	43 min
May 18, 4:27 PM CDT	Severe Thunderstorm Warning Destructive damage threat	EAX	Atchison	78 min
May 18, 4:34 PM CDT	Tornado Warning	EAX	Atchison	26 min
May 18, 4:39 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OAX	Fremont, Page	66 min
May 18, 4:55 PM CDT	Tornado Warning	EAX	Atchison	35 min
May 18, 5:06 PM CDT	Tornado Warning	OAX	Fremont, Page	54 min
May 18, 5:13 PM CDT	Severe Thunderstorm Warning	OAX	Page	62 min
May 18, 5:14 PM CDT	Tornado Warning	EAX	Nodaway	46 min
May 18, 5:16 PM CDT	Tornado Warning Tornado observed	EAX	Atchison, Holt	44 min
May 18, 5:22 PM CDT	Severe Thunderstorm Warning Considerable damage threat	EAX	Atchison, Holt, Nodaway	53 min
May 18, 5:34 PM CDT	Severe Thunderstorm Warning	DMX	Adams, Taylor	56 min
May 18, 5:40 PM CDT	Tornado Warning	DMX	Taylor	65 min
May 18, 5:41 PM CDT	Tornado Warning Considerable damage threat	EAX	Holt, Nodaway	49 min
May 18, 6:06 PM CDT	Severe Thunderstorm Warning Considerable damage threat	EAX	Atchison, Holt, Nodaway	39 min
May 18, 6:13 PM CDT	Flash Flood Warning	EAX	Atchison, Holt, Nodaway	4 hr
May 18, 6:18 PM CDT	Severe Thunderstorm Warning	OAX	Fremont, Mills	31 min
May 18, 6:22 PM CDT	Severe Thunderstorm Warning	DMX	Ringgold, Taylor, Union	53 min
May 18, 6:29 PM CDT	Tornado Warning	EAX	Gentry, Nodaway, Worth	46 min
May 18, 6:31 PM CDT	Tornado Warning	DMX	Ringgold, Taylor	59 min
May 18, 6:33 PM CDT	Severe Thunderstorm Warning Considerable damage threat	EAX	Gentry, Nodaway, Worth	57 min
May 18, 6:37 PM CDT	Severe Thunderstorm Warning	OAX	Mills, Montgomery, Pottawattamie	14 min
May 18, 6:38 PM CDT	Severe Thunderstorm Warning	EAX	Atchison	52 min
May 18, 6:58 PM CDT	Tornado Warning	EAX	Atchison	47 min
May 18, 7:06 PM CDT	Tornado Warning Tornado observed	DMX	Clarke, Decatur, Ringgold, Union	39 min
May 18, 7:09 PM CDT	Tornado Warning	EAX	Gentry, Worth	51 min
May 18, 7:15 PM CDT	Severe Thunderstorm Warning Considerable damage threat	EAX	Doniphan	60 min
May 18, 7:16 PM CDT	Tornado Warning	DMX	Ringgold, Taylor	44 min
May 18, 7:18 PM CDT	Severe Thunderstorm Warning	OAX	Page	32 min
May 18, 7:22 PM CDT	Tornado Warning	EAX	Harrison, Worth	53 min
May 18, 7:29 PM CDT	Tornado Warning	EAX	Holt	31 min
May 18, 7:30 PM CDT	Severe Thunderstorm Warning Considerable damage threat	EAX	Atchison	45 min
May 18, 7:39 PM CDT	Tornado Warning	DMX	Jasper, Marion, Polk, Warren	41 min
May 18, 7:39 PM CDT	Tornado Warning	EAX	Nodaway, Worth	51 min
May 18, 7:41 PM CDT	Severe Thunderstorm Warning	DMX	Jasper, Polk, Warren	49 min
May 18, 7:41 PM CDT	Severe Thunderstorm Warning Considerable damage threat	EAX	Doniphan	49 min
May 18, 8:01 PM CDT	Severe Thunderstorm Warning	EAX	Doniphan	44 min
May 18, 8:04 PM CDT	Severe Thunderstorm Warning Considerable damage threat	EAX	Doniphan	41 min
May 18, 8:08 PM CDT	Severe Thunderstorm Warning	DMX	Jasper, Marshall, Polk, Story	52 min
May 18, 8:09 PM CDT	Flash Flood Warning	EAX	Nodaway, Worth	5 hr
May 18, 8:15 PM CDT	Severe Thunderstorm Warning	EAX	Atchison, Doniphan	45 min
May 18, 8:18 PM CDT	Tornado Warning	DMX	Jasper, Marshall	16 min
May 18, 8:26 PM CDT	Severe Thunderstorm Warning	EAX	Gentry, Harrison, Nodaway, Worth	49 min
May 18, 8:35 PM CDT	Severe Thunderstorm Warning	EAX	Andrew, Buchanan, Daviess, DeKalb, Gentry, Harrison and 1 more	40 min
May 18, 8:36 PM CDT	Tornado Warning	EAX	Andrew, Daviess, DeKalb, Gentry, Harrison	24 min
May 18, 8:42 PM CDT	Severe Thunderstorm Warning	EAX	Atchison, Doniphan, Leavenworth	63 min
May 18, 8:57 PM CDT	Tornado Warning	EAX	Daviess, Grundy, Harrison	33 min
May 18, 9:06 PM CDT	Tornado Warning	DMX	Poweshiek, Tama	16 min
May 18, 9:06 PM CDT	Severe Thunderstorm Warning	EAX	Daviess, Gentry, Grundy, Harrison, Mercer, Sullivan and 1 more	39 min
May 18, 9:13 PM CDT	Severe Thunderstorm Warning Considerable damage threat	EAX	Buchanan, Caldwell, Cass, Clay, Clinton, Jackson and 2 more	62 min
May 18, 9:17 PM CDT	Flash Flood Warning	DMX	Decatur, Ringgold, Taylor	6 hr
May 18, 9:37 PM CDT	Severe Thunderstorm Warning Considerable damage threat	EAX	Caldwell, Carroll, Daviess, Grundy, Lafayette, Livingston and 1 more	53 min
May 18, 9:43 PM CDT	Severe Thunderstorm Warning	EAX	Grundy, Mercer, Putnam, Sullivan	33 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, 8.8 hours before the alert went out and 141 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: 871 m above ground
0-6 km bulk shear: 49 kt
0-1 km storm-relative helicity: 271 m²/s²
0-3 km storm-relative helicity: 220 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, 7:40 PM CDT	Mesoscale Discussion	SPC	Adair, Adams, Audubon, Boone, Calhoun, Carroll and 29 more	65 min
May 17, 7:49 PM CDT	Mesoscale Discussion	SPC	Cerro Gordo, Emmet, Floyd, Franklin, Hancock, Howard and 7 more	56 min
May 17, 8:07 PM CDT	Tornado Watch	SPC	Adair, Adams, Audubon, Black Hawk, Boone, Calhoun and 29 more	5 hr
May 17, 8:18 PM CDT	Mesoscale Discussion	SPC	Buena Vista, Cherokee, Clay, Emmet, Humboldt, Ida and 5 more	27 min
May 17, 9:30 PM CDT	Mesoscale Discussion	SPC	Adair, Adams, Audubon, Boone, Butler, Calhoun and 37 more	90 min
May 17, 10:32 PM CDT	Mesoscale Discussion	SPC	Allamakee, Black Hawk, Boone, Bremer, Buchanan, Butler and 14 more	118 min
May 17, 11:10 PM CDT	Severe Thunderstorm Watch	SPC	Allamakee, Appanoose, Benton, Buchanan, Cedar, Clayton and 13 more	5 hr
May 18, 1:24 AM CDT	Mesoscale Discussion	SPC	Appanoose, Cedar, Davis, Dubuque, Henry, Iowa and 12 more	96 min
May 18, 6:51 AM CDT	Mesoscale Discussion	SPC	Des Moines, Henry, Lee	84 min
May 18, 3:29 PM CDT	Mesoscale Discussion	SPC	Adair, Adams, Audubon, Cass, Clarke, Decatur and 12 more	2 hr
May 18, 5:10 PM CDT	Mesoscale Discussion	SPC	Cherokee, Lyon, Monona, O'Brien, Osceola, Plymouth and 2 more	95 min
May 17, 7:40 PM CDT	Tornado Watch	SPC	Edwards, Ford, Hodgeman, Kiowa, Ness, Pawnee and 3 more	3 hr
May 18, 11:59 AM CDT	Mesoscale Discussion	SPC	Brown, Chase, Clay, Cloud, Dickinson, Ellsworth and 20 more	2 hr
May 18, 12:50 PM CDT	Tornado Watch PDS	SPC	Barton, Brown, Clay, Cloud, Dickinson, Ellsworth and 18 more	7 hr
May 18, 2:07 PM CDT	Mesoscale Discussion	SPC	Clay, Cloud, Lincoln, Marshall, Ottawa, Washington	83 min
May 18, 2:31 PM CDT	Mesoscale Discussion	SPC	Barber, Clark, Comanche, Edwards, Kiowa, Pratt and 1 more	119 min
May 18, 3:00 PM CDT	Tornado Watch	SPC	Barber, Clark, Comanche, Edwards, Ford, Kiowa and 3 more	6 hr
May 18, 5:45 PM CDT	Mesoscale Discussion	SPC	Atchison, Brown, Doniphan, Jackson, Marshall, Nemaha and 2 more	2 hr
May 18, 6:14 PM CDT	Tornado Watch	SPC	Anderson, Butler, Chase, Chautauqua, Coffey, Cowley and 24 more	7 hr

Nearby

Tornado Watches in Iowa, 2026 Tornado Watches in Missouri, 2026 Tornado Watches in Kansas, 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.