Heavy storms dumped up to 18 inches of rain on Central Texas overnight, sending floodwaters through several Hill Country towns Wednesday and leaving dozens of people on rooftops, cars and in trees.

No fatalities were immediately reported in the latest series of summertime Texas storms, which have killed at least 11 people in the past week and a half. The downpour and winds were so treacherous early Wednesday that helicopters were forced to abruptly halt efforts to rescue people from rooftops.

A 13-year-old boy died Tuesday night when he was washed down a flooded creek in the Dallas suburb of Garland.

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Eight people were injured when nearly 100 mph winds hit the Permian Basin in West Texas late Tuesday. A 320-foot radio tower collapsed onto the Agape Community Church in Seminole and crushed a bus. No one was in the building at the time of the crash.

"It's hard to believe it, looking at the church. But it is what it is, we live in a windy town," Nic Billman, youth and worship pastor at the church, said in Thursday's Odessa American.

Rains were heaviest in the Marble Falls area, about 40 miles northwest of Austin, where Mayor Raymond Whitman said there were 32 high-water rescues. Austin-area officials said there were reports of up to 20 people needing to be saved.

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Whitman, whose own living room was filled with water Tuesday night, said some looting had been reported in flood-damaged areas and extra police officers would be on duty throughout the night. No curfew had been mandated, but Whitman said he would institute one if people were out.

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With as much as 10 inches of rain forecast overnight, lakefront residents in two subdivisions near Buchanan Dam were being advised to evacuate. In one area, about seven families were being evacuated from their homes by helicopter because the roads were not passable.

"I'll be pleasantly surprised if we don't end up with some fatalities over this," said Austin-Travis County Emergency Medical Services spokesman Warren Hassinger.

Hassinger said four rescue attempts before dawn were abandoned because of weather, and he didn't know what happened to the people needing help. One aborted rescue had attempted to get four people from the roof of a house in Granite Shoals.

The Texas National Guard dispatched troops and vehicles to Central Texas, as well as other areas hit by storms from the Oklahoma Border to the Rio Grande Valley. About 150 troops and 50 vehicles were mobilized.

While Whitman said there were no known fatalities, he said it was unclear whether people managed to escape safely from the empty vehicles scattered around the town of about 7,200 residents.

"We don't know if they got out," he said.

He said the flooding washed out three bridges and also tore the back wall off the funeral home. About two-thirds of the city was without water because of damage to the water treatment plant. A temporary pump was being installed and city officials hoped water would be restored before nightfall.

Bottled water requested from the state early Wednesday had not yet been delivered by late afternoon. Water tankers to help fight fires that may result from spilled fuel also had not arrived.

"This is the worst I've ever seen it in my lifetime," said Whitman, 47, who has lived in the town his entire life.

Whitman Branch creek in Marble Falls, typically 2-3 feet wide, stretched at least 100 feet across. Several nearby buildings were flooded, and vehicles had swept down the creek and overturned. The smell of gas and diesel fuel were heavy in the air.

Paul Irvin found his sheet metal shop near the creek under 6 feet of water.

"It was a sick feeling to see everything you've worked so hard for washing down," said Irvin, who said his 20 employees more than likely are out of work for a while.

Down the creek, at least four Frito Lay trucks that had been loaded to make daily deliveries had washed away, spilling chips along the creek. One large truck emblazoned with the Doritos logo was stuck on its side in the still-running water.

Dennis Heffington, an employee for Oasis Pest Control, spent the morning roaming the debris-filled streets in search of his pickup truck. He found it on its side in the water, about 300 yards from where it had been parked.

By midday, much of the water had receded, but city officials expected several more inches of rain over the next 24 hours.

"The ground is fully saturated ... it could be severe," Whitman said. "If people do not pay attention and move to high ground, it is very possible that there will be fatalities."

Storm runoff is making its way to Central Texas lakes, causing major flooding in some areas, according to the Lower Colorado River Authority. Floodgates have been opened at several dams, raising the Colorado River's water level in Austin, Bastrop, Smithville, La Grange and Wharton. But officials did not expect the river to exceed flood stage.

Rains drenched North Texas as well, creating flooding along some creeks and rivers and forcing the evacuation of at least 50 homes in a subdivision near Lake Granbury about 60 miles southwest of Dallas. There, about 30 homes were destroyed, said Hood County Sheriff Gene Mayo. About 25 people were rescued from the water, trees and rooftops, he said.

Floodwaters were rising along the Brazos River between Possum Kingdom Reservoir and Lake Granbury on Wednesday after the U.S. Army Corps of Engineers opened the floodgates on the Possum Kingdom dam.

In Parker County west of Fort Worth, County Judge Mark Riley has declared an emergency and ordered mandatory evacuation of subdivisions along the Brazos.

It's the wettest year on record in Austin, where more than 30 inches of rain has fallen since January, and Dallas-Fort Worth, Waco and Wichita Falls have also received near record amounts. The rainfall has more than compensated for a drought that much of Texas had been experiencing since 2005, National Weather Service meteorologist Mark Lenz said.

There's a good chance of showers and thunderstorms into the weekend in Central Texas, Lenz said, though the rainfall shouldn't be as heavy as it has been. Still, even a small amount of rain could cause more flash flooding because the soil is saturated.

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