Tornado, Boone
- When
- May 7, 4:00 PM CST
- Where
- Boone County
- Rating
- F2
- Path width
- 67 yd
- Property damage
- $25,000
- Coordinates
- 42.100, -93.900
Tornadoes and Hail in Iowa, May 7, 1964
7 tornado, 3 hail, 3 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
- 28
- Property damage
- $28 million
- Crop damage
- None recorded
- Events
- 13
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
7 tornado, 3 hail, 3 thunderstorm wind. Local standard time, as filed.
Hail, Howard
- When
- May 7, 4:30 PM CST
- Where
- Howard County
- Measured
- 1 in hail
- Coordinates
- 43.380, -92.080
Tornado, Buchanan
- When
- May 7, 5:10 PM CST
- Where
- Buchanan County
- Rating
- F3
- Path length
- 2.3 mi
- Path width
- 200 yd
- Injuries
- 1 direct, 0 indirect
- Property damage
- $250,000
- Coordinates
- 42.600, -91.900
Thunderstorm Wind, Grundy
- When
- May 7, 5:10 PM CST
- Where
- Grundy County
- Coordinates
- 42.500, -92.680
Tornado, Fayette
- When
- May 7, 5:28 PM CST
- Where
- Fayette County
- Rating
- F2
- Path length
- 2 mi
- Path width
- 250 yd
- Property damage
- $2.5 million
- Coordinates
- 42.670, -91.880
Tornado, Hardin
- When
- May 7, 5:30 PM CST
- Where
- Hardin County
- Rating
- F1
- Path length
- 2 mi
- Path width
- 100 yd
- Property damage
- $25,000
- Coordinates
- 42.300, -93.300
Tornado, Black Hawk
- When
- May 7, 5:30 PM CST
- Where
- Black Hawk County
- Rating
- F2
- Path length
- 7.1 mi
- Path width
- 200 yd
- Injuries
- 27 direct, 0 indirect
- Property damage
- $25 million
- Coordinates
- 42.520, -92.330
Thunderstorm Wind, Guthrie
- When
- May 7, 6:00 PM CST
- Where
- Guthrie County
- Coordinates
- 41.580, -94.400
Tornado, Guthrie
- When
- May 7, 6:30 PM CST
- Where
- Guthrie County
- Rating
- F2
- Path length
- 2 mi
- Path width
- 200 yd
- Property damage
- $25,000
- Coordinates
- 41.830, -94.550
Hail, Fremont
- When
- May 7, 6:30 PM CST
- Where
- Fremont County
- Measured
- 2 in hail
- Coordinates
- 40.700, -95.580
Tornado, Black Hawk
- When
- May 7, 6:35 PM CST
- Where
- Black Hawk County
- Rating
- F1
- Path length
- 1 mi
- Path width
- 100 yd
- Property damage
- $25,000
- Coordinates
- 42.500, -93.420
Thunderstorm Wind, Delaware
- When
- May 7, 9:43 PM CST
- Where
- Delaware County
- Coordinates
- 42.500, -91.500
Hail, Fremont
- When
- May 7, 10:30 PM CST
- Where
- Fremont County
- Measured
- 3 in hail
- Coordinates
- 40.780, -95.580
What these are
- 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.
- 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.
After NWS Directive 10-1605, the rules offices file Storm Data by.
The same day elsewhere
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: 10014432, 10014433, 10014434, 10014435, 10011943, 10011944, 10011945, 10011946, 10011947, 10011948, 10012164, 10012165, 10012166.