Louisville was swamped Tuesday by rain that shut down a university campus and turned streets and parking lots into lakes as a strong thunderstorm landed atop Kentucky's largest city and refused to budge.

Floodwaters gushed over guardrails on northbound Interstate 65, causing a massive traffic jam as the downpour turned the morning commute into a soggy adventure that stranded motorists.

"I've seen a lot of water, a lot of rain," said B. Thomas Thacker, a psychoanalyst with an office near downtown. "People are pretty well trapped."

Emergency rooms at a couple of hospitals were cut off from ambulances due to flooded roads, Mayor Jerry Abramson said.

The storm essentially shut down the University of Louisville, where about a dozen buildings were without power and a dozen more had some flooding on the main campus, said university spokesman Mark Hebert.

Craig Buthod, director of Louisville's public library system, said 3 1/2 feet of water inundated the main library's lower level. He said tens of thousands of books have been lost and the library was forced to close. He said his own vehicle along with staff vehicles and bookmobiles were flooded.

National Weather Service hydrologist Mike Callahan said the Rubbertown area in western Louisville was swamped by more than 6 inches of rain in three hours Tuesday morning.

Other parts of the city received more than 4 or 5 inches of rain.

Callahan said the slow-moving storm "went right into Louisville and just sat there."

Bud Schardein, who heads the Metropolitan Sewer District, said during flooding of 1997 there was 12 inches of rainfall in a 30-hour period. He said Tuesday there was 6 inches in about one hour.

"This is the most ever recorded rainfall in this community in an hour," Abramson said.

City officials said there had been no reports of significant injuries.

At the University of Louisville's health sciences campus downtown, a half-dozen buildings were flooded, spokesman Hebert said.

Dozens of university of employees were evacuated from flooded buildings, he said.

"This is the worst flooding that the University of Louisville campus has seen in anybody's memory," Hebert said.

The storm also pelted the city with marble-sized hail, and high winds downed tree limbs.

Louisville resident John Sastre said he saw several small cars stalled in flood waters, and was trying to pull a stranded relative out of high water with his sports utility vehicle.

"This is the first time I've seen it like this," said Sastre, a Louisville resident for 18 years.

Britt Singer was floating in an inflatable boat in a neighborhood between downtown and UofL.

"This is enjoyable," he said. "How often do I get to sail down my street in the middle of Old Louisville?"

A flash flood warning was in effect into the afternoon for Louisville and other parts of the metro area, and forecasters said the region could be hit by more thunderstorms in the afternoon.

Thunderstorms packing high winds also rumbled across other parts of Kentucky on Tuesday.

Heavy rains moved east into central Kentucky, causing flash flooding in Montgomery County. Donna Pharris, supervisor of the Montgomery County emergency dispatch center, said numerous roads were covered by water by late morning.

A flash flood warning was posted until mid-afternoon for portions of east-central Kentucky that received more than 2 inches of rain during the morning.

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