Hail, Grundy
- When
- June 17, 2:35 PM CST
- Where
- Grundy County
- Measured
- 2 in hail
- Coordinates
- 42.230, -92.880
Tornadoes and Hail in Iowa, June 17, 1984
9 thunderstorm wind, 7 tornado, 1 hail, 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
- 4
- Property damage
- $303,000
- Crop damage
- None recorded
- Events
- 17
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
9 thunderstorm wind, 7 tornado, 1 hail. Local standard time, as filed.
Thunderstorm Wind, Grundy
- When
- June 17, 2:35 PM CST
- Where
- Grundy County
- Measured
- 52 kt (60 mph)
- Coordinates
- 42.230, -92.880
Thunderstorm Wind, Black Hawk
- When
- June 17, 3:05 PM CST
- Where
- Black Hawk County
- Measured
- 52 kt (60 mph)
- Coordinates
- 42.520, -92.450
Tornado, Woodbury
- When
- June 17, 4:25 PM CST
- Where
- Woodbury County
- Rating
- F0
- Path width
- 33 yd
- Coordinates
- 42.450, -96.070
Thunderstorm Wind, Clayton
- When
- June 17, 4:25 PM CST
- Where
- Clayton County
- Coordinates
- 42.730, -91.470
Tornado, Woodbury
- When
- June 17, 4:27 PM CST
- Where
- Woodbury County
- Rating
- F0
- Path width
- 33 yd
- Coordinates
- 42.500, -96.070
Tornado, Cherokee
- When
- June 17, 4:29 PM CST
- Where
- Cherokee County
- Rating
- F0
- Path width
- 33 yd
- Coordinates
- 42.680, -95.700
Thunderstorm Wind, Delaware
- When
- June 17, 4:29 PM CST
- Where
- Delaware County
- Coordinates
- 42.520, -91.370
Thunderstorm Wind, Woodbury
- When
- June 17, 4:38 PM CST
- Where
- Woodbury County
- Injuries
- 4 direct, 0 indirect
- Coordinates
- 42.320, -96.280
Thunderstorm Wind, Harrison
- When
- June 17, 6:00 PM CST
- Where
- Harrison County
- Coordinates
- 41.670, -95.780
Thunderstorm Wind, Monona
- When
- June 17, 6:10 PM CST
- Where
- Monona County
- Coordinates
- 42.030, -95.930
Tornado, Harrison
- When
- June 17, 6:24 PM CST
- Where
- Harrison County
- Rating
- F1
- Path length
- 7 mi
- Path width
- 30 yd
- Property damage
- $25,000
- Coordinates
- 41.820, -96.070
Tornado, Iowa
- When
- June 17, 6:25 PM CST
- Where
- Iowa County
- Rating
- F1
- Path length
- 2 mi
- Path width
- 40 yd
- Property damage
- $250,000
- Coordinates
- 41.670, -92.200
Tornado, Harrison
- When
- June 17, 6:43 PM CST
- Where
- Harrison County
- Rating
- F0
- Path length
- 0.1 mi
- Path width
- 10 yd
- Property damage
- $3,000
- Coordinates
- 41.520, -95.620
Thunderstorm Wind, Pocahontas
- When
- June 17, 7:30 PM CST
- Where
- Pocahontas County
- Measured
- 61 kt (70 mph)
- Coordinates
- 42.800, -94.680
Tornado, Cedar
- When
- June 17, 7:35 PM CST
- Where
- Cedar County
- Rating
- F1
- Path length
- 0.5 mi
- Path width
- 40 yd
- Property damage
- $25,000
- Coordinates
- 41.670, -91.080
Thunderstorm Wind, Marion
- When
- June 17, 9:40 PM CST
- Where
- Marion County
- Coordinates
- 41.420, -92.930
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
More
Every storm in Iowa in 1984Every state in 1984This day in weather historyThe tornado archive for Iowa, 1984
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: 10014225, 10014226, 10014227, 10014228, 10014229, 10012737, 10012738, 10012739, 10012740, 10012741, 10012742, 10012743, 10012744, 10012745, 10012746, 10012747, 10012748.