A potent shortwave embedded in northwest flow moved across Iowa, providing a focus from storm development in an environment that already had MLCAPE values of 2500-3000 J/kg and effective bulk shear of around 40 knots. Convection that occurred earlier in the morning of July 11th also provided a focus for storm development on lingering outflow boundaries. This allowed for swaths of large hail across the state, with reports of up to tennis ball sized hail in some locations.

Funnel Cloud in POCAHONTAS, IOWA
From 11-JUL-20 12:45:00 to 11-JUL-20 12:45:00 (CST-6)
Location: PALMER
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Multiple reports via social media of a funnel cloud southeast of Pocahontas and southwest of Gilmore City.

Hail in WEBSTER, IOWA
From 11-JUL-20 13:15:00 to 11-JUL-20 13:15:00 (CST-6)
Location: CLARE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public report via social media of quarter sized hail.

Hail in WEBSTER, IOWA
From 11-JUL-20 13:27:00 to 11-JUL-20 13:27:00 (CST-6)
Location: FT DODGE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported quarter sized hail on the northwest side of Fort Dodge.

Hail in WEBSTER, IOWA
From 11-JUL-20 13:29:00 to 11-JUL-20 13:29:00 (CST-6)
Location: FT DODGE
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported golf ball sized hail.

Hail in WEBSTER, IOWA
From 11-JUL-20 13:38:00 to 11-JUL-20 13:38:00 (CST-6)
Location: FT DODGE
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported ping pong ball sized hail near Fort Dodge.

Hail in WEBSTER, IOWA
From 11-JUL-20 13:41:00 to 11-JUL-20 13:41:00 (CST-6)
Location: FT DODGE
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported quarter to golf ball sized hail southeast of Fort Dodge.

Thunderstorm Wind in WEBSTER, IOWA
From 11-JUL-20 13:42:00 to 11-JUL-20 13:42:00 (CST-6)
Location: COALVILLE
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

A social media picture showed damage to sweet corn east of Coalville. Possible that damage was due to a mix of hail and wind, which flattened the corn. Time estimated via radar.

Hail in PALO ALTO, IOWA
From 11-JUL-20 13:54:00 to 11-JUL-20 13:54:00 (CST-6)
Location: RUTHVEN
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

A report relayed via KICD of golf ball sized hail. Time estimated via radar.

Hail in KOSSUTH, IOWA
From 11-JUL-20 13:58:00 to 11-JUL-20 13:58:00 (CST-6)
Location: BANCROFT
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

A report via social media of ping pong ball sized hail.

Hail in PALO ALTO, IOWA
From 11-JUL-20 13:58:00 to 11-JUL-20 13:58:00 (CST-6)
Location: RUTHVEN
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

A report relayed via KICD of quarter sized hail.

Hail in FRANKLIN, IOWA
From 11-JUL-20 14:15:00 to 11-JUL-20 14:15:00 (CST-6)
Location: SHEFFIELD
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

A social media report of ping pong ball sized hail in Sheffield.

Heavy Rain in CERRO GORDO, IOWA
From 11-JUL-20 13:23:00 to 11-JUL-20 14:23:00 (CST-6)
Location: MASON CITY
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

A delayed report relayed via broadcast media of 2.5 inches of rain in Mason City ending at 3:23 pm. Begin time estimated via radar.

Hail in KOSSUTH, IOWA
From 11-JUL-20 14:24:00 to 11-JUL-20 14:24:00 (CST-6)
Location: WESLEY
Magnitude: 2.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

A public report of 2 inch hail.

Hail in PALO ALTO, IOWA
From 11-JUL-20 14:24:00 to 11-JUL-20 14:24:00 (CST-6)
Location: MALLARD
Magnitude: 2.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

KICD radio relayed a report of hail up to tennis ball size near Mallard. Time and location estimated via radar.

Hail in BUTLER, IOWA
From 11-JUL-20 14:26:00 to 11-JUL-20 14:26:00 (CST-6)
Location: CLARKSVILLE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

NWS employee reported quarter sized hail southwest of Clarksville.

Hail in WORTH, IOWA
From 11-JUL-20 14:30:00 to 11-JUL-20 14:30:00 (CST-6)
Location: HANLONTOWN
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Broadcast media relayed a report of ping pong ball sized hail just north of Hanlontown occurring around 3:30 pm.

Hail in BUTLER, IOWA
From 11-JUL-20 14:34:00 to 11-JUL-20 14:34:00 (CST-6)
Location: COSTER
Magnitude: 2.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

A report via social media of tennis ball sized hail. Time and location estimated via radar.

Hail in STORY, IOWA
From 11-JUL-20 14:40:00 to 11-JUL-20 14:40:00 (CST-6)
Location: GILBERT
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported quarter sized hail at the intersection of E18 and R38 northwest of Gilbert.

Hail in STORY, IOWA
From 11-JUL-20 14:43:00 to 11-JUL-20 14:43:00 (CST-6)
Location: STORY CITY
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Law enforcement reported quarter to ping pong ball sized hail in Story City lasting 1 to 2 minutes.

Hail in HANCOCK, IOWA
From 11-JUL-20 14:45:00 to 11-JUL-20 14:45:00 (CST-6)
Location: KANAWHA
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

KCCI replayed a report and picture of ping pong ball sized hail near Kanawha. Time estimated via radar.

Hail in BUTLER, IOWA
From 11-JUL-20 14:46:00 to 11-JUL-20 14:46:00 (CST-6)
Location: NEW HARTFORD
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public report of ping pong ball sized hail.

Hail in BUTLER, IOWA
From 11-JUL-20 14:51:00 to 11-JUL-20 14:51:00 (CST-6)
Location: NEW HARTFORD
Magnitude: 2.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

KWWL relayed a report of 2 inch hail. Time and location estimated via radar.

Hail in BLACK HAWK, IOWA
From 11-JUL-20 14:54:00 to 11-JUL-20 14:54:00 (CST-6)
Location: FINCHFORD
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

KWWL relayed a report of quarter sized hail. Time and location estimated via radar.

Thunderstorm Wind in CERRO GORDO, IOWA
From 11-JUL-20 14:54:00 to 11-JUL-20 14:54:00 (CST-6)
Location: (MCW)MASON CITY MUNI
Magnitude: 54.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

The Mason City airport reported a wind gust of 54 knots.

Hail in BLACK HAWK, IOWA
From 11-JUL-20 14:58:00 to 11-JUL-20 14:58:00 (CST-6)
Location: NORTH CEDAR
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

KWWL relayed a report of nickel sized hail. Time and location estimated via radar.

Hail in CERRO GORDO, IOWA
From 11-JUL-20 15:02:00 to 11-JUL-20 15:02:00 (CST-6)
Location: MASON CITY
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported quarter sized hail one mile north of Mason City.

Hail in BLACK HAWK, IOWA
From 11-JUL-20 15:20:00 to 11-JUL-20 15:20:00 (CST-6)
Location: CEDAR FALLS ARPT
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

KWWL relayed a report of quarter sized hail. Time and location estimated via radar.

Hail in BLACK HAWK, IOWA
From 11-JUL-20 15:24:00 to 11-JUL-20 15:24:00 (CST-6)
Location: CEDAR FALLS ARPT
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported quarter sized hail.

Hail in BLACK HAWK, IOWA
From 11-JUL-20 15:31:00 to 11-JUL-20 15:31:00 (CST-6)
Location: CEDAR FALLS ARPT
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

A public report of 1.25 inch hail was relayed to the office.

Hail in GRUNDY, IOWA
From 11-JUL-20 15:39:00 to 11-JUL-20 15:39:00 (CST-6)
Location: FERN
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported quarter sized hail.

Hail in STORY, IOWA
From 11-JUL-20 16:18:00 to 11-JUL-20 16:18:00 (CST-6)
Location: ROLAND
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

A public report via social media of golf ball sized hail.

Hail in STORY, IOWA
From 11-JUL-20 16:19:00 to 11-JUL-20 16:19:00 (CST-6)
Location: ROLAND
Magnitude: 2.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Emergency manager relayed a report of tennis ball sized hail at the intersection of 620th ave and 120th st in Story County.

Hail in STORY, IOWA
From 11-JUL-20 16:20:00 to 11-JUL-20 16:20:00 (CST-6)
Location: ROLAND
Magnitude: 2.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

KCCI relayed a report of tennis ball sized hail.

Hail in STORY, IOWA
From 11-JUL-20 16:21:00 to 11-JUL-20 16:21:00 (CST-6)
Location: ROLAND
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Emergency manager reported nickel to quarter sized hail.

Hail in STORY, IOWA
From 11-JUL-20 16:30:00 to 11-JUL-20 16:30:00 (CST-6)
Location: MC CALLSBURG
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public report via social media of golf ball sized hail.

Hail in STORY, IOWA
From 11-JUL-20 16:32:00 to 11-JUL-20 16:32:00 (CST-6)
Location: COLO
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported quarter sized hail on US 65 halfway between Colo and Zearing.

Hail in STORY, IOWA
From 11-JUL-20 16:32:00 to 11-JUL-20 16:32:00 (CST-6)
Location: MC CALLSBURG
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported 1.25 inch hail 1 mile southwest of McCallsburg.

Hail in STORY, IOWA
From 11-JUL-20 16:48:00 to 11-JUL-20 16:48:00 (CST-6)
Location: NEVADA
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Law enforcement reported quarter sized hail in Nevada.

Hail in STORY, IOWA
From 11-JUL-20 16:55:00 to 11-JUL-20 16:55:00 (CST-6)
Location: COLLINS
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Emergency manager reported ping pong ball sized hail.

Hail in STORY, IOWA
From 11-JUL-20 16:55:00 to 11-JUL-20 16:55:00 (CST-6)
Location: COLLINS
Magnitude: 2.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Emergency manager reported 2 inch hail.

Hail in STORY, IOWA
From 11-JUL-20 17:00:00 to 11-JUL-20 17:00:00 (CST-6)
Location: COLO
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported 1.25 to 1.5 inch hail southeast of Colo.

Hail in STORY, IOWA
From 11-JUL-20 17:04:00 to 11-JUL-20 17:04:00 (CST-6)
Location: COLLINS
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

A public report via social media of nickel sized hail.

Hail in JASPER, IOWA
From 11-JUL-20 17:11:00 to 11-JUL-20 17:11:00 (CST-6)
Location: BAXTER
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

The Baxter Fire Department reported quarter sized hail.

Hail in JASPER, IOWA
From 11-JUL-20 17:30:00 to 11-JUL-20 17:30:00 (CST-6)
Location: KELLOGG
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported quarter sized hail 4 miles east of Newton.

Hail in POLK, IOWA
From 11-JUL-20 18:20:00 to 11-JUL-20 18:20:00 (CST-6)
Location: WEST DES MOINES
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported penny sized hail.

Hail in WARREN, IOWA
From 11-JUL-20 18:54:00 to 11-JUL-20 18:54:00 (CST-6)
Location: INDIANOLA
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported quarter sized hail.