Convection began in early afternoon in eastern Iowa along a subtle boundary across the state. This was fueled by high CAPE exceeding 3000 J/kg with deep layer shear sufficient to support large hail growth. Later in the evening a secondary round of convection moved across the area producing additional hail in the form of a cold pool driven MCS, driven along the plume of higher instability. The result was dozen of hail reports up to baseball sized across much of central and southern Iowa, damaging homes and vehicles and taking down power lines. As storms crossed Interstate 80 an accident resulted in significant delays.

Hail in STORY, IOWA
From 07-MAY-23 14:10:00 to 07-MAY-23 14:10:00 (CST-6)
Location: AMES
Magnitude: 2.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Image received via twitter.

Hail in STORY, IOWA
From 07-MAY-23 14:10:00 to 07-MAY-23 14:10:00 (CST-6)
Location: AMES
Magnitude: 2.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Hail in STORY, IOWA
From 07-MAY-23 14:30:00 to 07-MAY-23 14:30:00 (CST-6)
Location: MC CALLSBURG
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Report submitted via social media.

Hail in STORY, IOWA
From 07-MAY-23 14:38:00 to 07-MAY-23 14:38:00 (CST-6)
Location: MAXWELL
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in STORY, IOWA
From 07-MAY-23 14:42:00 to 07-MAY-23 14:42:00 (CST-6)
Location: COLLINS
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in STORY, IOWA
From 07-MAY-23 14:42:00 to 07-MAY-23 14:42:00 (CST-6)
Location: COLLINS
Magnitude: 54.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Grain bin blown into field, time estimated by radar.

Thunderstorm Wind in STORY, IOWA
From 07-MAY-23 14:45:00 to 07-MAY-23 14:45:00 (CST-6)
Location: COLLINS
Magnitude: 55.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Report of power lines down heading eastbound on 310th street from Collins. Timing estimated by radar.

Hail in JASPER, IOWA
From 07-MAY-23 14:47:00 to 07-MAY-23 14:47:00 (CST-6)
Location: CLYDE
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Time estimated by radar.

Hail in TAMA, IOWA
From 07-MAY-23 14:49:00 to 07-MAY-23 14:49:00 (CST-6)
Location: TOLEDO
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in STORY, IOWA
From 07-MAY-23 14:49:00 to 07-MAY-23 14:49:00 (CST-6)
Location: COLLINS
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in JASPER, IOWA
From 07-MAY-23 14:56:00 to 07-MAY-23 14:56:00 (CST-6)
Location: GODDARD
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Image submitted via social media indicating ping pong ball sized hail outside of Colfax. Location estimated based on radar.

Hail in JASPER, IOWA
From 07-MAY-23 15:00:00 to 07-MAY-23 15:00:00 (CST-6)
Location: BAXTER
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Golf ball sized hail and strong winds.

Hail in MARSHALL, IOWA
From 07-MAY-23 15:00:00 to 07-MAY-23 15:00:00 (CST-6)
Location: MELBOURNE
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Timing based off radar data.

Hail in JASPER, IOWA
From 07-MAY-23 15:00:00 to 07-MAY-23 15:00:00 (CST-6)
Location: BAXTER
Magnitude: 2.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Delayed report, submitted via social media.

Hail in MARSHALL, IOWA
From 07-MAY-23 15:14:00 to 07-MAY-23 15:14:00 (CST-6)
Location: LAUREL
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Image received via social media. Timing based on radar.

Hail in JASPER, IOWA
From 07-MAY-23 15:16:00 to 07-MAY-23 15:16:00 (CST-6)
Location: NEWTON
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in JASPER, IOWA
From 07-MAY-23 15:17:00 to 07-MAY-23 15:17:00 (CST-6)
Location: NEWTON
Magnitude: 2.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Image received via social media.

Hail in JASPER, IOWA
From 07-MAY-23 15:17:00 to 07-MAY-23 15:17:00 (CST-6)
Location: NEWTON
Magnitude: 2.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Image received via social media. Timing based on radar.

Hail in JASPER, IOWA
From 07-MAY-23 15:20:00 to 07-MAY-23 15:20:00 (CST-6)
Location: NEWTON MUNI ARPT
Magnitude: 2.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Report received via social media.

Hail in JASPER, IOWA
From 07-MAY-23 15:20:00 to 07-MAY-23 15:20:00 (CST-6)
Location: NEWTON
Magnitude: 2.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Golf ball to baseball sized hail.

Hail in JASPER, IOWA
From 07-MAY-23 15:21:00 to 07-MAY-23 15:21:00 (CST-6)
Location: NEWTON MUNI ARPT
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Report via mping.

Hail in JASPER, IOWA
From 07-MAY-23 15:30:00 to 07-MAY-23 15:30:00 (CST-6)
Location: KELLOGG
Magnitude: 2.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Reports submitted via social media of golf ball to two inch hail south of Kellogg. Time estimated by radar.

Hail in JASPER, IOWA
From 07-MAY-23 15:33:00 to 07-MAY-23 15:33:00 (CST-6)
Location: SULLY
Magnitude: 2.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Report via social media.

Hail in JASPER, IOWA
From 07-MAY-23 15:34:00 to 07-MAY-23 15:34:00 (CST-6)
Location: TURNER
Magnitude: 2.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Image submitted via social media with a range of hail stone size along I-80. Time estimated by radar.

Hail in POWESHIEK, IOWA
From 07-MAY-23 15:40:00 to 07-MAY-23 15:40:00 (CST-6)
Location: GRINNELL ARPT
Magnitude: 2.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Baseball sized hail with strong winds. Report via social media.

Hail in POWESHIEK, IOWA
From 07-MAY-23 15:42:00 to 07-MAY-23 15:42:00 (CST-6)
Location: GRINNELL
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Report via social media.

Thunderstorm Wind in POWESHIEK, IOWA
From 07-MAY-23 15:42:00 to 07-MAY-23 15:42:00 (CST-6)
Location: GRINNELL ARPT
Magnitude: 55.00 EG
Property damage: 30.00K
Crop damage: 0.00K
Reported by: Public

Trailers blown over at a dealership south of Grinnell. Report via social media.

Hail in POWESHIEK, IOWA
From 07-MAY-23 15:45:00 to 07-MAY-23 15:45:00 (CST-6)
Location: GRINNELL
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

Hail in POWESHIEK, IOWA
From 07-MAY-23 15:50:00 to 07-MAY-23 15:50:00 (CST-6)
Location: GRINNELL ARPT
Magnitude: 2.75 
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Spotter reported strong winds with potential damage and large hail with wide range of sizes.

Thunderstorm Wind in POWESHIEK, IOWA
From 07-MAY-23 15:53:00 to 07-MAY-23 15:53:00 (CST-6)
Location: GRINNELL ARPT
Magnitude: 55.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

Semi trailer blown over at mile marker 185 on interstate 80 between Grinnell and Malcom exits. Seen via Iowa DOT cameras.

Hail in POWESHIEK, IOWA
From 07-MAY-23 15:57:00 to 07-MAY-23 15:57:00 (CST-6)
Location: MONTEZUMA
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Report via social media.

Hail in POWESHIEK, IOWA
From 07-MAY-23 16:00:00 to 07-MAY-23 16:00:00 (CST-6)
Location: MONTEZUMA
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Reported 56mph winds with nickel to quarter sized hail.

Hail in POWESHIEK, IOWA
From 07-MAY-23 16:00:00 to 07-MAY-23 16:00:00 (CST-6)
Location: MONTEZUMA
Magnitude: 2.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Delayed report, time estimated by radar.

Hail in MAHASKA, IOWA
From 07-MAY-23 16:22:00 to 07-MAY-23 16:22:00 (CST-6)
Location: LACEY
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Report of quarter sized hail with potentially a few larger stones present.

Hail in MAHASKA, IOWA
From 07-MAY-23 16:41:00 to 07-MAY-23 16:41:00 (CST-6)
Location: ROSE HILL
Magnitude: 2.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Delayed report, time estimated via radar.

Hail in MAHASKA, IOWA
From 07-MAY-23 16:43:00 to 07-MAY-23 16:43:00 (CST-6)
Location: ROSE HILL
Magnitude: 2.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Delayed report, time estimated by radar. Report via social media.

Hail in ADAIR, IOWA
From 07-MAY-23 18:50:00 to 07-MAY-23 18:50:00 (CST-6)
Location: BRIDGEWATER
Magnitude: 2.50 
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Largest stornes were tennis ball sized and resulted in damage to siding on house.

Hail in ADAIR, IOWA
From 07-MAY-23 18:56:00 to 07-MAY-23 18:56:00 (CST-6)
Location: BRIDGEWATER
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in ADAIR, IOWA
From 07-MAY-23 18:45:00 to 07-MAY-23 19:05:00 (CST-6)
Location: BRIDGEWATER
Magnitude: 2.25 
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail fell for about 20 minutes and included damage to siding.

Hail in GUTHRIE, IOWA
From 07-MAY-23 20:20:00 to 07-MAY-23 20:20:00 (CST-6)
Location: JAMAICA
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

Dime to nickel sized hail.

Hail in UNION, IOWA
From 07-MAY-23 20:21:00 to 07-MAY-23 20:21:00 (CST-6)
Location: SPAULDING
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Hail in BREMER, IOWA
From 07-MAY-23 20:21:00 to 07-MAY-23 20:21:00 (CST-6)
Location: DENVER
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Report via social media, time estimated by radar.

Hail in HARDIN, IOWA
From 07-MAY-23 20:33:00 to 07-MAY-23 20:33:00 (CST-6)
Location: PT PLEASANT
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Hail in BOONE, IOWA
From 07-MAY-23 21:00:00 to 07-MAY-23 21:00:00 (CST-6)
Location: OGDEN
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Thunderstorm Wind in CLARKE, IOWA
From 07-MAY-23 21:16:00 to 07-MAY-23 21:16:00 (CST-6)
Location: OSCEOLA
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Storm Chaser

Estimated severe straight line winds with minor flying debris near the I-35 and Highway 34 interchange.

Hail in CLARKE, IOWA
From 07-MAY-23 21:41:00 to 07-MAY-23 21:41:00 (CST-6)
Location: WELDON
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

One inch hail northwest of Le Roy.

Hail in CLARKE, IOWA
From 07-MAY-23 21:48:00 to 07-MAY-23 21:48:00 (CST-6)
Location: WOODBURN
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Report via mping, time estimated by radar.

Hail in MARION, IOWA
From 07-MAY-23 21:56:00 to 07-MAY-23 21:56:00 (CST-6)
Location: BUSSEY
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in CARROLL, IOWA
From 07-MAY-23 12:20:00 to 07-MAY-23 12:20:00 (CST-6)
Location: MANNING
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Dime to quarter sized hail.

Hail in CARROLL, IOWA
From 07-MAY-23 12:37:00 to 07-MAY-23 12:37:00 (CST-6)
Location: CARROLL
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Report via broadcast media.

Hail in CARROLL, IOWA
From 07-MAY-23 12:40:00 to 07-MAY-23 12:40:00 (CST-6)
Location: CARROLL
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Quarter sized hail in Carroll relayed by Law Enforcement.

Hail in LUCAS, IOWA
From 07-MAY-23 22:05:00 to 07-MAY-23 22:05:00 (CST-6)
Location: LUCAS
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Report via mping.

Hail in CARROLL, IOWA
From 07-MAY-23 12:40:00 to 07-MAY-23 12:40:00 (CST-6)
Location: CARROLL
Magnitude: 2.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Report via social media.

Hail in GREENE, IOWA
From 07-MAY-23 13:07:00 to 07-MAY-23 13:07:00 (CST-6)
Location: SCRANTON
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Report from twitter, time estimated by radar.

Hail in BOONE, IOWA
From 07-MAY-23 13:50:00 to 07-MAY-23 13:50:00 (CST-6)
Location: BOONE
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

Hail in STORY, IOWA
From 07-MAY-23 13:55:00 to 07-MAY-23 13:55:00 (CST-6)
Location: GILBERT
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Penny sized hail.

Hail in STORY, IOWA
From 07-MAY-23 13:56:00 to 07-MAY-23 13:56:00 (CST-6)
Location: STORY CITY
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Story county law enforcement reports nickel to quarter sized hail is falling.

Hail in STORY, IOWA
From 07-MAY-23 14:02:00 to 07-MAY-23 14:02:00 (CST-6)
Location: GILBERT
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in STORY, IOWA
From 07-MAY-23 14:04:00 to 07-MAY-23 14:04:00 (CST-6)
Location: GILBERT
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in STORY, IOWA
From 07-MAY-23 14:07:00 to 07-MAY-23 14:07:00 (CST-6)
Location: ONTARIO
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in STORY, IOWA
From 07-MAY-23 14:07:00 to 07-MAY-23 14:07:00 (CST-6)
Location: STORY CITY
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in STORY, IOWA
From 07-MAY-23 14:08:00 to 07-MAY-23 14:08:00 (CST-6)
Location: AMES
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Image received via social media.

Hail in STORY, IOWA
From 07-MAY-23 14:08:00 to 07-MAY-23 14:08:00 (CST-6)
Location: GILBERT
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Hail in STORY, IOWA
From 07-MAY-23 14:10:00 to 07-MAY-23 14:10:00 (CST-6)
Location: AMES
Magnitude: 2.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

One to two inch hail.