Tornado and Hail in Iowa, May 21, 1998

Name: Tornado and Hail in Iowa, May 21, 1998
Start: 1998-05-21T19:45
End: 1998-05-21T23:40
Location: Iowa

May 21, 1998 · NWS DMX · 38 events in 11 counties and zones

A frontal boundary remained nearly stationary to the south of Iowa. Thunderstorms fired up as warm air over ran the cooler air at the surface.

Where it happened

Every event with a place to put it. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 2
Property damage: $606,000
Crop damage: $107,000
Events: 38

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS DMX wrote it up.

A frontal boundary remained nearly stationary to the south of Iowa. Thunderstorms fired up as warm air over ran the cooler air at the surface. Storms formed over Nebraska and moved into western Iowa during the mid evening hours, then continued to advance east across the state. For the most part the storms produced high winds with wind gusts to 70 MPH or more at times. Winds gusted to 77 MPH west of Greenfield in Adair County. There were numerous reports of trees and power lines downed. One injury occurred in Union County as campers were overturned at Green Valley State Park by the high winds. Another injury occurred in Cass County when 65 to 80 MPH winds blew through. Three semi-tractortrailers and one car were overturned by high winds in Interstate 80. There were also many reports of farm sheds and buildings being damaged or destroyed by the winds. Some building damage was reported in Creston. A barn and farm shed was destroyed by high winds in Wayne County near Seymour. Early in the storms development, a small tornado touched down in Cass County north of Anita. The tornado destroyed several sheds and grain bins there. In addition to the wind, there were numerous reports of marble size hail. Hail was not a major event with these storms however. The only large hail reports came early on in the event with golf ball size hail at Brayton in Audubon County, and one inch diameter hail reported in Cass County northwest of Atlantic.

The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

32 thunderstorm wind, 5 hail, 1 tornado. Local standard time, as filed.

Thunderstorm Wind, Audubon

When: May 21, 7:45 PM CST
Where: Audubon County, Kimballton
Measured: 52 kt (60 mph)
Property damage: $10,000
Crop damage: $1,000
Coordinates: 41.570, -95.080

Thunderstorm Wind, Cass

When: May 21, 8:00 PM CST
Where: Cass County, 7 mi NW of Atlantic
Measured: 57 kt (66 mph)
Injuries: 1 direct, 0 indirect
Property damage: $50,000
Crop damage: $5,000
Reported by: BROADCAST MEDIA
Coordinates: 41.470, -95.120

Thunderstorm Wind, Cass

When: May 21, 8:10 PM CST
Where: Cass County, 7 mi NE of Atlantic
Measured: 57 kt (66 mph)
Property damage: $10,000
Crop damage: $5,000
Reported by: BROADCAST MEDIA
Coordinates: 41.470, -94.920

Thunderstorm Wind, Cass

When: May 21, 8:12 PM CST
Where: Cass County, Atlantic Arpt
Measured: 54 kt (62 mph)
Property damage: $1,000
Coordinates: 41.400, -95.050

Thunderstorm Wind, Cass

When: May 21, 8:13 PM CST
Where: Cass County, Atlantic
Measured: 69 kt (79 mph)
Property damage: $70,000
Crop damage: $3,000
Reported by: BROADCAST MEDIA
Coordinates: 41.400, -95.020

Thunderstorm Wind, Cass

When: May 21, 8:15 PM CST
Where: Cass County, Anita
Measured: 56 kt (64 mph)
Property damage: $10,000
Coordinates: 41.450, -94.770

Thunderstorm Wind, Cass

When: May 21, 8:18 PM CST
Where: Cass County, Atlantic
Measured: 52 kt (60 mph)
Property damage: $15,000
Coordinates: 41.400, -95.020

Hail, Audubon

When: May 21, 8:20 PM CST
Where: Audubon County, Brayton
Measured: 1.75 in hail
Property damage: $10,000
Crop damage: $10,000
Coordinates: 41.550, -94.930

Hail, Cass

When: May 21, 8:20 PM CST
Where: Cass County, 5 mi NW of Atlantic
Measured: 1 in hail
Property damage: $1,000
Crop damage: $5,000
Coordinates: 41.450, -95.080

Thunderstorm Wind, Cass

When: May 21, 8:20 PM CST
Where: Cass County, 2 mi E of Atlantic
Measured: 52 kt (60 mph)
Property damage: $3,000
Crop damage: $10,000
Coordinates: 41.400, -94.980

Small hail covered the ground

Tornado, Cass

When: May 21, 8:20 PM CST
Where: Cass County, 1 mi N of Anita
Rating: F1
Path length: 0.5 mi
Path width: 35 yd
Property damage: $75,000
Crop damage: $2,000
Coordinates: 41.470, -94.770

Thunderstorm Wind, Audubon

When: May 21, 8:20 PM CST
Where: Audubon County, Exira to 7 mi SE of Exira
Measured: 61 kt (70 mph)
Property damage: $4,000
Coordinates: 41.520, -94.780

Thunderstorm Wind, Cass

When: May 21, 8:22 PM CST
Where: Cass County, Wiota
Measured: 69 kt (79 mph)
Property damage: $50,000
Crop damage: $5,000
Reported by: BROADCAST MEDIA
Coordinates: 41.400, -94.900

Hail, Cass

When: May 21, 8:23 PM CST
Where: Cass County, 3 mi N of Wiota
Measured: 1 in hail
Property damage: $1,000
Crop damage: $5,000
Coordinates: 41.450, -94.900

Hail, Cass

When: May 21, 8:23 PM CST
Where: Cass County, 1 mi N of Anita
Measured: 1 in hail
Property damage: $1,000
Crop damage: $5,000
Coordinates: 41.470, -94.770

Thunderstorm Wind, Audubon

When: May 21, 8:24 PM CST
Where: Audubon County, Brayton
Measured: 52 kt (60 mph)
Property damage: $5,000
Coordinates: 41.550, -94.930

Hail, Cass

When: May 21, 8:25 PM CST
Where: Cass County, 2 mi W of Wiota
Measured: 1.75 in hail
Property damage: $4,000
Crop damage: $25,000
Reported by: BROADCAST MEDIA
Coordinates: 41.400, -94.930

Thunderstorm Wind, Union

When: May 21, 8:27 PM CST
Where: Union County, Afton
Measured: 58 kt (67 mph)
Property damage: $20,000
Crop damage: $5,000
Coordinates: 41.030, -94.200

Thunderstorm Wind, Adair

When: May 21, 8:45 PM CST
Where: Adair County, Fontanelle
Measured: 70 kt (81 mph)
Property damage: $100,000
Crop damage: $5,000
Coordinates: 41.300, -94.570

Thunderstorm Wind, Adair

When: May 21, 8:50 PM CST
Where: Adair County, Bridgewater
Measured: 61 kt (70 mph)
Property damage: $5,000
Crop damage: $500
Coordinates: 41.250, -94.680

Thunderstorm Wind, Adair

When: May 21, 9:15 PM CST
Where: Adair County, 5 mi W of Greenfield
Measured: 67 kt (77 mph)
Property damage: $10,000
Crop damage: $1,000
Coordinates: 41.300, -94.570

Thunderstorm Wind, Union

When: May 21, 9:30 PM CST
Where: Union County, Lorimor
Measured: 50 kt (58 mph)
Property damage: $2,000
Coordinates: 41.130, -94.070

Thunderstorm Wind, Madison

When: May 21, 9:30 PM CST
Where: Madison County, Macksburg
Measured: 61 kt (70 mph)
Property damage: $10,000
Crop damage: $1,000
Coordinates: 41.220, -94.180

Thunderstorm Wind, Madison

When: May 21, 9:30 PM CST
Where: Madison County, Truro
Measured: 50 kt (58 mph)
Property damage: $1,000
Coordinates: 41.220, -93.870

Thunderstorm Wind, Union

When: May 21, 9:35 PM CST
Where: Union County, 3 mi NW of Creston
Measured: 55 kt (63 mph)
Injuries: 1 direct, 0 indirect
Property damage: $10,000
Crop damage: $1,000
Coordinates: 41.100, -94.400

Thunderstorm Wind, Dallas

When: May 21, 9:35 PM CST
Where: Dallas County, Adel
Measured: 52 kt (60 mph)
Property damage: $1,000
Coordinates: 41.620, -94.020

Thunderstorm Wind, Madison

When: May 21, 9:40 PM CST
Where: Madison County, Truro
Measured: 50 kt (58 mph)
Property damage: $2,000
Coordinates: 41.220, -93.870

Thunderstorm Wind, Union

When: May 21, 9:40 PM CST
Where: Union County, 6 mi N of Creston
Measured: 56 kt (64 mph)
Property damage: $5,000
Coordinates: 41.150, -94.370

Thunderstorm Wind, Union

When: May 21, 9:40 PM CST
Where: Union County, Creston
Measured: 61 kt (70 mph)
Property damage: $15,000
Crop damage: $1,000
Coordinates: 41.070, -94.370

Thunderstorm Wind, Clarke

When: May 21, 10:05 PM CST
Where: Clarke County, Osceola
Measured: 50 kt (58 mph)
Property damage: $5,000
Coordinates: 41.030, -93.780

Thunderstorm Wind, Warren

When: May 21, 10:08 PM CST
Where: Warren County, 3 mi NW of Indianola
Measured: 50 kt (58 mph)
Property damage: $5,000
Coordinates: 41.400, -93.600

Thunderstorm Wind, Wayne

When: May 21, 10:30 PM CST
Where: Wayne County, 8 mi S of Humeston
Measured: 56 kt (64 mph)
Property damage: $10,000
Crop damage: $1,000
Coordinates: 40.750, -93.480

Thunderstorm Wind, Wayne

When: May 21, 10:40 PM CST
Where: Wayne County, Corydon
Measured: 52 kt (60 mph)
Property damage: $5,000
Coordinates: 40.770, -93.320

Thunderstorm Wind, Lucas

When: May 21, 10:40 PM CST
Where: Lucas County, Lucas
Measured: 50 kt (58 mph)
Property damage: $2,000
Coordinates: 41.030, -93.470

Thunderstorm Wind, Wayne

When: May 21, 10:43 PM CST
Where: Wayne County, Promise City
Measured: 52 kt (60 mph)
Property damage: $3,000
Coordinates: 40.750, -93.150

Thunderstorm Wind, Wayne

When: May 21, 11:00 PM CST
Where: Wayne County, Seymour
Measured: 65 kt (75 mph)
Property damage: $70,000
Crop damage: $10,000
Coordinates: 40.680, -93.120

Thunderstorm Wind, Appanoose

When: May 21, 11:15 PM CST
Where: Appanoose County, Centerville
Measured: 50 kt (58 mph)
Property damage: $2,000
Coordinates: 40.730, -92.870

Thunderstorm Wind, Appanoose

When: May 21, 11:40 PM CST
Where: Appanoose County, Moulton
Measured: 52 kt (60 mph)
Property damage: $3,000
Coordinates: 40.680, -92.670

What these are

Thunderstorm Wind: Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.
Hail: Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.
Tornado: A violently rotating column of air in contact with the ground and extending from a thunderstorm, filed with its path, width and Fujita or Enhanced Fujita rating from the damage survey.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Iowa in 1998 Every state in 1998 This day in weather history The tornado archive for Iowa, 1998 Warnings in Iowa, May 1998

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 5646800, 5646808, 5646809, 5646673, 5646805, 5646674, 5646802, 5646675, 5646676, 5646677, 5646777, 5646778, 5646806, 5646779, 5646780, 5646781, 5646807, 5646801, 5646782, 5646783, 5646784, 5646785, 5646786, 5646787, 5646788, 5646789, 5646790, 5646791, 5646792, 5646793, 5646794, 5646795, 5646796, 5646797, 5646798, 5646803, 5646799, 5646804.