During the early morning hours of July 17 a frontal boundary was pushing north across central Kentucky while a shortwave moved across the region.  This led to the development of widespread thunderstorms across southern Indiana and north central Kentucky.  These storms produced damaging winds and marginally severe hail.  During the afternoon hours differential heating and leftover outflow boundaries combined with heating of the day to produce additional thunderstorms across the region.

Thunderstorm Wind in SHELBY, KENTUCKY
From 17-JUL-10 01:42:00 to 17-JUL-10 01:42:00 (EST-5)
Location: VIGO
Magnitude: 78.00 EG
Reported by: NWS Storm Survey

A powerful microburst occurred early Saturday morning as a severe thunderstorm rolled across Shelby County. Most of the damage occurred between 2:30 AM and 3:00 AM EDT when numerous trees were reported down across the county. This caused several power outages early Saturday morning.  Fortunately there was no major damage to any homes in the vicinity.  Based on the size and types of trees down, some spots likely saw speeds as high as 85 to 90 mph.  A NWS Damage Survey indicated that some of the damage northeast of Shelbyville may have been related to gustnadoes, with both cyclonic and anti-cyclonic rotation noted in fallen trees, as well as in an area of flattened corn.
The damage area extended primarily north of U.S. Highway 60 from Shelbyville to Bagdad.

Thunderstorm Wind in HENRY, KENTUCKY
From 17-JUL-10 01:52:00 to 17-JUL-10 01:52:00 (EST-5)
Location: DEFOE
Magnitude: 52.00 EG
Reported by: Law Enforcement

Power lines were blown down near the Shelby county line.

Thunderstorm Wind in OLDHAM, KENTUCKY
From 17-JUL-10 15:53:00 to 17-JUL-10 15:53:00 (EST-5)
Location: WESTPORT
Magnitude: 52.00 EG
Reported by: Law Enforcement

Trees were blown down on Smith Lane.

Thunderstorm Wind in OLDHAM, KENTUCKY
From 17-JUL-10 16:07:00 to 17-JUL-10 16:07:00 (EST-5)
Location: BALLARDSVILLE
Magnitude: 52.00 EG
Reported by: Law Enforcement

Power lines were blown down between La Grange and Ballardsville.  This sparked a small grass fire.

Thunderstorm Wind in SHELBY, KENTUCKY
From 17-JUL-10 17:48:00 to 17-JUL-10 17:48:00 (EST-5)
Location: VEACHLAND
Magnitude: 52.00 EG
Reported by: Trained Spotter

A tree was blown down on Old 7 Mile Pike in Shelbyville.

Thunderstorm Wind in JEFFERSON, KENTUCKY
From 17-JUL-10 00:50:00 to 17-JUL-10 00:50:00 (EST-5)
Location: HIGHVIEW
Magnitude: 52.00 EG
Reported by: Emergency Manager

Numerous trees were blown down on the south side of Jefferson county.  Emergency management reported 1500 people were without power.

Thunderstorm Wind in JEFFERSON, KENTUCKY
From 17-JUL-10 00:28:00 to 17-JUL-10 00:28:00 (EST-5)
Location: PENILE
Magnitude: 52.00 EG
Reported by: Emergency Manager

Several trees were blown down on the south side of Louisville west of Interstate 65.

Heavy Rain in SHELBY, KENTUCKY
From 17-JUL-10 18:27:00 to 17-JUL-10 18:27:00 (EST-5)
Location: SHELBYVILLE
Reported by: CoCoRaHS

An observer reported 2.10 inches of rain fell in 80 minutes.

Thunderstorm Wind in JEFFERSON, KENTUCKY
From 17-JUL-10 00:44:00 to 17-JUL-10 00:44:00 (EST-5)
Location: SMYRNA
Magnitude: 52.00 EG
Reported by: NWS Employee

Estimated wind gusts of 60 mph were observed at the National Weather Service office.

Thunderstorm Wind in BULLITT, KENTUCKY
From 17-JUL-10 00:40:00 to 17-JUL-10 00:40:00 (EST-5)
Location: BROOKS
Magnitude: 52.00 EG
Reported by: Trained Spotter

Estimated wind gusts of 60 mph were observed a half mile south of the Jefferson County line on Preston Highway.

Hail in HENRY, KENTUCKY
From 17-JUL-10 16:25:00 to 17-JUL-10 16:25:00 (EST-5)
Location: PENDLETON
Magnitude: 0.88 
Reported by: Public

Hail in OLDHAM, KENTUCKY
From 17-JUL-10 15:55:00 to 17-JUL-10 15:55:00 (EST-5)
Location: LA GRANGE
Magnitude: 0.88 
Reported by: Public

Hail in HENRY, KENTUCKY
From 17-JUL-10 02:17:00 to 17-JUL-10 02:17:00 (EST-5)
Location: PORT ROYAL
Magnitude: 1.00 
Reported by: Broadcast Media

Flash Flood in SHELBY, KENTUCKY
From 17-JUL-10 18:10:00 to 17-JUL-10 18:10:00 (EST-5)
Location: MONTCLAIR
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

Flash flooding briefly closed three roads just west of Shelbyville.  The roads were Antioch, Scott Station, and Jail Hill.

Thunderstorm Wind in OLDHAM, KENTUCKY
From 17-JUL-10 17:16:00 to 17-JUL-10 17:16:00 (EST-5)
Location: LA GRANGE
Magnitude: 52.00 EG
Reported by: Law Enforcement

Several trees were blown down in La Grange and Buckner.