Thunderstorm Wind, Wapello
- When
- April 20, 7:48 AM CST
- Where
- Wapello County
- Measured
- 80 kt (92 mph)
- Coordinates
- 41.080, -92.400
Tornadoes and Damaging Wind in Iowa, April 20, 1964
3 tornado, 1 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
The toll
- Deaths
- 0
- Injuries
- 2
- Property damage
- $300,000
- 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 tornado, 1 thunderstorm wind. Local standard time, as filed.
Tornado, Fremont
- When
- April 20, 9:40 PM CST
- Where
- Fremont County
- Rating
- F2
- Path length
- 2.7 mi
- Path width
- 300 yd
- Property damage
- $25,000
- Coordinates
- 40.750, -95.470
Tornado, Montgomery
- When
- April 20, 10:00 PM CST
- Where
- Montgomery County
- Rating
- F2
- Path width
- 350 yd
- Injuries
- 1 direct, 0 indirect
- Property damage
- $250,000
- Coordinates
- 40.900, -95.380
Tornado, Cass
- When
- April 20, 10:30 PM CST
- Where
- Cass County
- Rating
- F3
- Path length
- 6.1 mi
- Path width
- 350 yd
- Injuries
- 1 direct, 0 indirect
- Property damage
- $25,000
- Coordinates
- 41.400, -95.050
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
- Tornadoes and Hail in Kansas, April 20, 1964
- Tornadoes and Damaging Wind in Nebraska, April 20, 1964
- Tornado and Hail in Oklahoma, April 20, 1964
- Hail in Texas, April 20, 1964
- Damaging Winds in Missouri, April 20, 1964
- Hail and Damaging Wind in West Virginia, April 20, 1964
- Damaging Wind in Ohio, April 20, 1964
- Damaging Wind in Illinois, April 20, 1964
More
Every storm in Iowa in 1964Every state in 1964This day in weather historyThe tornado archive for Iowa, 1964
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: 10014411, 10014412, 10014413, 10014414.