The Gulf Coast, Southeast and Tennessee River Valley face the threat of tornadoes and flash flooding from a large storm that includes the remnants of Hurricane Patricia, forecasters say.

The storm created the biggest deluge in Texas since torrential rains in May washed away homes and killed dozens. But a hot and dry summer allowed the ground to soak up more water this time, according to National Weather Service meteorologist Scott Overpeck.

Authorities said Sunday that only about two dozen cars around Houston were towed from flooded streets. Francisco Sanchez, a spokesman for Harris County's emergency management division, said residents heeded warnings this time around.

At least 2,500 vehicles were stranded around Houston after Memorial Day storms dumped heavy rains and damaged thousands of homes.

“You can call it luck, you can call it blessed, you can call it all of those things"

- Chief Charles Hood

No deaths have been confirmed or major damage reported. The San Antonio Fire Department chief said a man who was swept into a flooded drainage ditch amid drenching rains has been found safe.

Chief Charles Hood announced at a press conference Sunday afternoon that the man was "washed out of the waterway" and eventually made his way to a road, where a passer-by spotted him. That person notified emergency responders.

“You can call it luck, you can call it blessed, you can call it all of those things,” Hood said, according to FOX29. “Due to the amount of water, the speed, you can imagine crashing along the walls in there with any type of debris and still being able to maintain his breath. It’s an amazing story.”

Authorities had previously said the man was walking his dog before dawn early Saturday when he was swept away. The man's dog is safe and he has been taken to a hospital for treatment.

"We were very pessimistic with finding him alive in this situation," Hood said.

The Associated Press contributed to this report.