Tornadoes and Hail in Iowa, May 9, 1986

Name: Tornadoes and Hail in Iowa, May 9, 1986
Start: 1986-05-09T00:05
End: 1986-05-09T22:30
Location: Iowa

May 9, 1986 · 20 events in 6 counties and zones

11 tornado, 7 hail, 2 thunderstorm wind, as filed by the National Weather Service.

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: 0
Property damage: None recorded
Crop damage: None recorded
Events: 20

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.

Event by event

11 tornado, 7 hail, 2 thunderstorm wind. Local standard time, as filed.

Thunderstorm Wind, Cass

When: May 9, 12:05 AM CST
Where: Cass County
Measured: 52 kt (60 mph)
Coordinates: 41.400, -95.080

Hail, Polk

When: May 9, 4:28 PM CST
Where: Polk County
Measured: 1.75 in hail
Coordinates: 41.600, -93.620

Hail, Boone

When: May 9, 4:40 PM CST
Where: Boone County
Measured: 1.75 in hail
Coordinates: 42.070, -93.950

Hail, Dallas

When: May 9, 6:00 PM CST
Where: Dallas County
Measured: 1.75 in hail
Coordinates: 41.520, -93.830

Hail, Polk

When: May 9, 6:04 PM CST
Where: Polk County
Measured: 1.75 in hail
Coordinates: 41.580, -93.720

Hail, Polk

When: May 9, 6:20 PM CST
Where: Polk County
Measured: 1.75 in hail
Coordinates: 41.670, -93.700

Tornado, Dallas

When: May 9, 6:36 PM CST
Where: Dallas County
Rating: F0
Path length: 0.1 mi
Path width: 10 yd
Coordinates: 41.600, -93.830

Tornado, Polk

When: May 9, 6:36 PM CST
Where: Polk County
Rating: F0
Path length: 0.1 mi
Path width: 10 yd
Coordinates: 41.580, -93.800

Tornado, Dallas

When: May 9, 6:40 PM CST
Where: Dallas County
Rating: F0
Path length: 0.1 mi
Path width: 10 yd
Coordinates: 41.580, -93.850

Tornado, Dallas

When: May 9, 6:48 PM CST
Where: Dallas County
Rating: F0
Path length: 0.1 mi
Path width: 10 yd
Coordinates: 41.570, -93.830

Tornado, Dallas

When: May 9, 6:55 PM CST
Where: Dallas County
Rating: F0
Path length: 0.1 mi
Path width: 10 yd
Coordinates: 41.620, -93.830

Tornado, Dallas

When: May 9, 7:09 PM CST
Where: Dallas County
Rating: F0
Path length: 0.1 mi
Path width: 10 yd
Coordinates: 41.620, -93.830

Tornado, Polk

When: May 9, 7:09 PM CST
Where: Polk County
Rating: F0
Path length: 0.1 mi
Path width: 10 yd
Coordinates: 41.620, -93.780

Tornado, Dallas

When: May 9, 7:12 PM CST
Where: Dallas County
Rating: F0
Path length: 0.1 mi
Path width: 10 yd
Coordinates: 41.620, -93.880

Thunderstorm Wind, Webster

When: May 9, 7:20 PM CST
Where: Webster County
Measured: 52 kt (60 mph)
Coordinates: 42.580, -94.150

Tornado, Dallas

When: May 9, 7:40 PM CST
Where: Dallas County
Rating: F0
Path length: 0.1 mi
Path width: 10 yd
Coordinates: 41.850, -93.920

Tornado, Polk

When: May 9, 7:49 PM CST
Where: Polk County
Rating: F0
Path length: 0.1 mi
Path width: 10 yd
Coordinates: 41.680, -93.800

Tornado, Dallas

When: May 9, 7:49 PM CST
Where: Dallas County
Rating: F0
Path length: 0.1 mi
Path width: 10 yd
Coordinates: 41.680, -93.820

Hail, Dallas

When: May 9, 8:05 PM CST
Where: Dallas County
Measured: 1.75 in hail
Coordinates: 41.770, -93.830

Hail, Pottawattamie

When: May 9, 10:30 PM CST
Where: Pottawattamie County
Measured: 1.75 in hail
Coordinates: 41.370, -95.870

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 1986 Every state in 1986 This day in weather history The tornado archive for Iowa, 1986 Warnings in Iowa, May 1986

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: 10013951, 10013952, 10013953, 10013954, 10013955, 10013956, 10013957, 10013958, 10013959, 10013960, 10013961, 10013962, 10013963, 10013964, 10013965, 10013966, 10013967, 10013968, 10013969, 10013970.