Tornado and Damaging Winds in Wisconsin, July 20, 1978

Name: Tornado and Damaging Winds in Wisconsin, July 20, 1978
Start: 1978-07-20T13:15
End: 1978-07-20T14:00
Location: Wisconsin

July 20, 1978 · NWS MT · 4 events in 4 counties and zones

3 thunderstorm wind, 1 tornado, 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

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The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 4

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

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

Thunderstorm Wind, Grant

When: July 20, 1:15 PM CST
Where: Grant County
Coordinates: 42.730, -90.480

Tornado, Green

When: July 20, 1:45 PM CST
Where: Green County
Path length: 0.5 mi
Path width: 100 yd
Coordinates: 42.700, -89.430

Thunderstorm Wind, Rock

When: July 20, 2:00 PM CST
Where: Rock County
Coordinates: 42.680, -89.020

Thunderstorm Wind, Jefferson

When: July 20, 2:00 PM CST
Where: Jefferson County
Coordinates: 42.930, -88.850

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.
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 Wisconsin in 1978 Every state in 1978 This day in weather history The tornado archive for Wisconsin, 1978

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: 10146077, 10146078, 10146079, 10146080.