A hot an humid air mass settled across the area with plenty of ambient instability available. As a complex of storms moved across Minnesota in the morning hours they put out an outflow boundary that moved into northern Iowa in the early afternoon. This provided just enough lift within such an unstable environment to initiate two main clusters of thunderstorms, producing some small hail along with gusty winds that caused tree and minor structural damage in north central Iowa.

Thunderstorm Wind in FRANKLIN, IOWA
From 24-AUG-21 12:21:00 to 24-AUG-21 12:21:00 (CST-6)
Location: HAMPTON MUNI ARPT
Magnitude: 56.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Thunderstorm Wind in BUTLER, IOWA
From 24-AUG-21 12:42:00 to 24-AUG-21 12:42:00 (CST-6)
Location: DUMONT
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public estimated winds at 50 to 60 mph with pea sized hail.

Thunderstorm Wind in BLACK HAWK, IOWA
From 24-AUG-21 13:19:00 to 24-AUG-21 13:19:00 (CST-6)
Location: (ALO)WATERLOO MUNI A
Magnitude: 53.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Thunderstorm Wind in BLACK HAWK, IOWA
From 24-AUG-21 13:22:00 to 24-AUG-21 13:22:00 (CST-6)
Location: CEDAR FALLS
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public estimated 60 mph winds.

Thunderstorm Wind in BLACK HAWK, IOWA
From 24-AUG-21 13:30:00 to 24-AUG-21 13:30:00 (CST-6)
Location: WATERLOO
Magnitude: 53.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Emergency Manager reported tree limbs and a few power lines downed. Ponding observed on area roadways.

Thunderstorm Wind in BREMER, IOWA
From 24-AUG-21 13:30:00 to 24-AUG-21 13:30:00 (CST-6)
Location: READLYN
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Crops flattened and trees down about 1 mile west of Readlyn.

Thunderstorm Wind in BREMER, IOWA
From 24-AUG-21 13:30:00 to 24-AUG-21 13:30:00 (CST-6)
Location: KNITTEL
Magnitude: 54.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Semi trailer turned over, bin blown into field, and bin roof blown off. Crops flattened and branches on houses. Time estimated by radar.

Thunderstorm Wind in BREMER, IOWA
From 24-AUG-21 13:38:00 to 24-AUG-21 13:38:00 (CST-6)
Location: HORTON
Magnitude: 55.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Trees down along highway 188. Time estimated by radar.

Thunderstorm Wind in BREMER, IOWA
From 24-AUG-21 13:40:00 to 24-AUG-21 13:40:00 (CST-6)
Location: TRIPOLI
Magnitude: 55.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Reports of trees downed and semi overturned in the Tripoli area.

Thunderstorm Wind in STORY, IOWA
From 24-AUG-21 14:36:00 to 24-AUG-21 14:36:00 (CST-6)
Location: STORY CITY
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Large tree limbs broken and heavy wood pen shifted. Time estimated by radar.

Hail in STORY, IOWA
From 24-AUG-21 14:38:00 to 24-AUG-21 14:38:00 (CST-6)
Location: STORY CITY
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported nickel sized hail and sustained 30 mph winds.

Thunderstorm Wind in MARSHALL, IOWA
From 24-AUG-21 15:28:00 to 24-AUG-21 15:28:00 (CST-6)
Location: MARIETTA
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Off duty officers reported damage to their home including shingles off and trees down. Time estimated by radar.