Elsewhere, people began to assess damage after more than a foot of rain fell in parts of the region.
The rains came late Wednesday and early Thursday, flooding homes in Lancaster and temporarily knocking out power to thousands.
A man's body and three vehicles were found late Thursday in a flooded creek downstream from a collapsed bridge in the small Ellis County town of Ovilla, officials said.
As fire and rescue crews continued searching the creek, County Judge Chad Adams said they expected to find more dead.
Adams said the bridge, a main thoroughfare in the town of 3,400, was swept out early Thursday as the severe storms moved through the Dallas-Fort Worth area. Some parts of the region received more than 13 inches of rain in the storms.
The Texas Department of Transportation was investigating what made some of the bridge's concrete columns collapse.
``We have two vehicles located. We have located one person deceased. We're still searching for another person that was in the second vehicle,'' Lt. Danny Williams of the Ellis County Sheriff's Department told the Waxahachie Daily Light.
Sheriff's officials said Michael Miles Sawyer, 52, of Ovilla apparently was on his way to work about 5:30 a.m. when the accident occurred on Ovilla Road at Red Oak Creek. Chief Deputy Charles Sullins said that the victim's body was found under piles of debris beneath a bridge in the Oak Leaf community.
In Arlington, firefighters responding to a report of a rain-related drowning found a man's body about 8:30 p.m. Thursday in an industrial area. The unidentified man's body was recovered about 100 yards downstream from his sport utility vehicle in Rush Creek, said police Sgt. David McGinty.
He said the victim was a security guard at Peyco Industrial Park and had been reported missing when he did not show up for work Thursday night.
``It looks like he got washed away in the rain,'' McGinty said.
In the south Dallas suburb of Lancaster, city officials were hoping for state and federal help after flooding damaged as many as 200 homes.
In Dallas, at least one death was caused by the weather Wednesday night when a motorist in a pickup truck knocked over a utility pole.
Jerry Johns, president of the Southwestern Insurance Information Service, said preliminary estimates for damages covered by homeowners policies - such as leaking roofs and flooded vehicles - totaled $17 million to $20 million in North Texas. Such private policies cover damage caused by falling rain, but not flooding on the ground, Johns said.
The peculiarly rainy summer in North Texas is due in part to atmospheric conditions that have blocked a high pressure ridge of air from forming, said Gary Woodall, meteorologist with National Weather Service. The ridge serves as a lid on the atmosphere that usually deflects upper level storms during the summer and keeps the region hot and dry.
Flash flood warnings were posted early Friday for Central Texas. Lightning started a fire at an out-of-use gas plant Thursday in Jourdanton. The lightning bolt hit a group of tanks at the plant on County Road 325, but the Atascosa County Sheriff's Department said no one was injured by the lightning or smoke. Hazardous materials crews said no poisons or hazardous materials were released.
