Thunderstorms developed during the afternoon in an environment with moderate instability, weak flow, and an abnormally high amount of atmospheric moisture. These storms tended to build continuously over the same locations. This created an enhanced potential for flooding and flash flooding. Some of these storms also became severe with large hail being the main threat.

Hail in WARREN, OHIO
From 04-MAY-12 16:13:00 to 04-MAY-12 16:17:00 (EST-5)
Location: SPRINGBORO
Magnitude: 0.75 
Reported by: Law Enforcement

Hail in MONTGOMERY, OHIO
From 04-MAY-12 16:14:00 to 04-MAY-12 16:18:00 (EST-5)
Location: GERMANTOWN
Magnitude: 1.00 
Reported by: Public

Hail in MONTGOMERY, OHIO
From 04-MAY-12 16:06:00 to 04-MAY-12 16:10:00 (EST-5)
Location: GERMANTOWN
Magnitude: 0.88 
Reported by: Public

Heavy Rain in CHAMPAIGN, OHIO
From 04-MAY-12 17:36:00 to 04-MAY-12 18:36:00 (EST-5)
Location: URBANA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Flooding of a farm field occurred due to heavy rain.

Heavy Rain in DELAWARE, OHIO
From 04-MAY-12 18:14:00 to 04-MAY-12 19:14:00 (EST-5)
Location: LEWIS CENTER
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Standing water about the depth of a tire was reported on area roadways due to heavy rain.

Heavy Rain in DELAWARE, OHIO
From 04-MAY-12 18:27:00 to 04-MAY-12 19:27:00 (EST-5)
Location: POWELL
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

About 3 inches of standing water was reported on roads in the area due to heavy rain. Some water was spilling onto the roads from adjacent fields.

Heavy Rain in AUGLAIZE, OHIO
From 04-MAY-12 21:10:00 to 04-MAY-12 22:10:00 (EST-5)
Location: ST MARYS
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Shallow water was reported over area roadways due to heavy rain.

Flash Flood in CHAMPAIGN, OHIO
From 04-MAY-12 19:00:00 to 04-MAY-12 20:00:00 (EST-5)
Location: WESTVILLE
Flood cause: Heavy Rain
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Due to heavy rainfall, high water was moving across Route 36 between Urbana and Westville, and near Route 235 west of Saint Paris. High water was also reported moving across Route 560.

Hail in WARREN, OHIO
From 04-MAY-12 16:05:00 to 04-MAY-12 16:09:00 (EST-5)
Location: FRANKLIN
Magnitude: 1.25 
Reported by: Public

Hail in BUTLER, OHIO
From 04-MAY-12 16:01:00 to 04-MAY-12 16:05:00 (EST-5)
Location: MIDDLETOWN
Magnitude: 0.88 
Reported by: Public

Flash Flood in HOCKING, OHIO
From 04-MAY-12 21:00:00 to 04-MAY-12 22:00:00 (EST-5)
Location: UNION FURNACE
Flood cause: Heavy Rain
Property damage: 100.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Flash flooding occurred in the area due to heavy rainfall. A driveway bridge washed out. Water was rushing into basements. Road damage occurred. Water was also reported in classrooms at an elementary school.

Hail in BUTLER, OHIO
From 04-MAY-12 15:57:00 to 04-MAY-12 16:01:00 (EST-5)
Location: MIDDLETOWN
Magnitude: 1.00 
Reported by: Trained Spotter

Flood in CLARK, OHIO
From 04-MAY-12 22:20:00 to 04-MAY-12 23:20:00 (EST-5)
Location: SPRINGFIELD
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

About 8 inches of water was reported over the road near the intersection of Columbus Avenue and Burnett Road due to heavy rainfall.

Hail in AUGLAIZE, OHIO
From 04-MAY-12 18:03:00 to 04-MAY-12 18:07:00 (EST-5)
Location: NEW KNOXVILLE
Magnitude: 0.75 
Reported by: Emergency Manager