Tornadoes and Hail in Iowa, July 20, 1999

Name: Tornadoes and Hail in Iowa, July 20, 1999
Start: 1999-07-20T16:01
End: 1999-07-20T16:36
Location: Iowa

July 20, 1999 · NWS ARX · 6 events in 2 counties and zones

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: $205,000
Crop damage: $105,000
Events: 6

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 ARX wrote it up.

A tornado touched down on the Floyd-Chickasaw County line north of Nashua, and moved northeast for 2 miles. Two farms had extensive damage, including a blown down silo, several damaged barns and outbuildings, sheared off trees, damaged crops and downed utility poles. Hail the size of golfballs and baseballs was also reported by law enforcement officials and a local television station.

The radar

The La Crosse radar (KARX), 149 km away, was scanning. The volume nearest the first event began at 22:00 UTC.

Open the radar archive at this moment

Event by event

3 hail, 2 tornado, 1 thunderstorm wind. Local standard time, as filed.

Hail, Floyd

When: July 20, 4:01 PM CST
Where: Floyd County, Floyd
Measured: 1.75 in hail
Property damage: $15,000
Crop damage: $20,000
Reported by: LAW ENFORCEMENT
Coordinates: 43.130, -92.770

Hail, Floyd

When: July 20, 4:18 PM CST
Where: Floyd County, Charles City
Measured: 2.75 in hail
Property damage: $35,000
Crop damage: $25,000
Reported by: BROADCAST MEDIA
Coordinates: 43.070, -92.700

Thunderstorm Wind, Floyd

When: July 20, 4:20 PM CST
Where: Floyd County, 1 mi SE of Carrville
Measured: 60 kt (69 mph)
Property damage: $10,000
Crop damage: $15,000
Reported by: NWS STORM SURVEY
Coordinates: 43.000, -92.580

Hail, Floyd

When: July 20, 4:20 PM CST
Where: Floyd County, Charles City
Measured: 1.75 in hail
Property damage: $25,000
Crop damage: $15,000
Reported by: BROADCAST MEDIA
Coordinates: 43.070, -92.700

Tornado, Floyd

When: July 20, 4:30 PM CST to 4:31 PM CST
Where: Floyd County, 1 mi SE of Carrville
Rating: F1
Path length: 0.1 mi
Path width: 60 yd
Crop damage: $15,000
Reported by: NWS STORM SURVEY
Coordinates: 43.000, -92.580

Tornado continued into Chickasaw County.

Tornado, Chickasaw

When: July 20, 4:31 PM CST to 4:36 PM CST
Where: Chickasaw County, Nashua to 4 mi NE of Nashua
Rating: F1
Path length: 2 mi
Path width: 80 yd
Property damage: $120,000
Crop damage: $15,000
Reported by: NWS STORM SURVEY
Coordinates: 42.980, -92.580

Tornado began in Floyd County

What these are

Hail: Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.
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.
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 1999 Every state in 1999 This day in weather history The tornado archive for Iowa, 1999 Warnings in Iowa, July 1999

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: 5707496, 5707556, 5707497, 5707555, 5707498, 5707557.