HOUSTON (AP) — Floodwaters kept rising Tuesday across much of Texas as storms dumped almost another foot of rain on the Houston area, stranding hundreds of motorists and inundating the famously congested highways that serve the nation's fourth-largest city.
San Marcos city spokeswoman Kristi Wyatt says 30 people whose whereabouts were previously unknown have been accounted for in Hays County, Texas, but that 13 people are still missing.
Eight of those who are missing were in a vacation home that was swept down the rain-swollen river and slammed into a bridge early Monday.
The area has seen two deaths because of the flash flooding: one in San Marcos and another in nearby Caldwell County.
The Blanco River rapidly rose to 44.5 feet — well above the flood stage of 13 feet — before a water gauge was knocked out.
Parts of the city are shown inundated after days of heavy rain on May 25, 2015 in Austin, Texas. Texas Gov. Greg Abbott toured the damage zone where one person is confirmed dead and at least 12 others missing in flooding along the Rio Blanco, which reports say rose as much as 40 feet in places, caused by more than 10 inches of rain over a four-day period. The governor earlier declared a state of emergency in 24 Texas counties. (Photo by Drew Anthony Smith/Getty Images)
The water continued rising overnight as the area received about 11 more inches, much of it in a six-hour period.
Firefighters carried out more than 500 water rescues, mostly stranded motorists. And at least 2,500 vehicles were abandoned on the streets by drivers seeking higher ground, said Rick Flanagan, Houston's emergency management coordinator.
"You cannot candy coat it. It's absolutely massive," Texas Gov. Greg Abbott said after touring the destruction.
The flooding closed several highways in Houston, and the ones that stayed open became a gridlocked mess.
Interstate 45 near downtown was backed up for miles on Tuesday morning, with a handful of motorists traveling the wrong way on the highway to retreat from high water.
The small cars weaved between massive 18-wheelers as drivers stared at them in disbelief. With no end to the backup in sight, some drivers got off the freeway, only to be held up again by water covering nearby access roads.
In the Heights neighborhood about 5 miles from downtown, groups of people roamed the streets after escaping their stalled cars, and police cruisers blocked some roads where the water had caused dangerous conditions.
Tape is stretched across a flooded Sixth Street after days of heavy rain on May 25, 2015 in Austin, Texas. (Photo by Drew Anthony Smith/Getty Images)
Some motorists were stuck on Interstate 45 all night, sleeping in their cars until the backup was cleared about 8 a.m.
NBA fans at the Toyota Center, where the Rockets hosted a Western Conference finals game against Golden State on Monday, were asked with about two minutes left in the game not to leave the arena because of the severe weather.
The game ended before 11 p.m., but about 400 people remained in their seats at 1:30 a.m., choosing to stay in the building rather than brave the flooded roads that awaited them outside.
Rain falls on May 25, 2015 in Austin, Texas. (Photo by Drew Anthony Smith/Getty Images)
Some of the worst flooding damage in Texas was in Wimberley, a popular tourist town along the Blanco River in the corridor between Austin and San Antonio. That's where the vacation home was swept away.
The "search component" of the mission ended Monday night, meaning no more survivors were expected to be found, said Trey Hatt, a spokesman for the Hays County Emergency Operations Center.
One person who was rescued from the home told workers that the other 12 inside were all connected to two families. Young children were among those believed to be missing.
A Car2Go sits partially submerged in the flood zone after days of heavy rain on May 25, 2015 in Austin, Texas. (Photo by Drew Anthony Smith/Getty Images)
But by early Tuesday, Hays County spokeswoman Laureen Chernow acknowledged discrepancies concerning exactly how many people were in the home.
"We don't have that certainty," Chernow said.
Eight of the missing were friends and family who had gathered for the holiday, said Kristi Wyatt, a spokeswoman for the City of San Marcos. She said three more were members of another family in a separate situation. An unrelated person was also missing, Wyatt said.
The Blanco crested above 40 feet — more than triple its flood stage of 13 feet. The river swamped Interstate 35 and closed parts of the busy north-south highway. Rescuers used pontoon boats and a helicopter to pull people out.
Hundreds of trees along the Blanco were uprooted or snapped, and they collected in piles of debris up to 20 feet high.
Lucas Rivas looks into the flooded Whole Earth Provisions Company on Lamar Street after days of heavy rain on May 25, 2015 in Austin, Texas. (Photo by Drew Anthony Smith/Getty Images)
A spokeswoman for the flood district of Harris County, which includes Houston, said up to 700 homes sustained some level of damage.
The deaths in Texas included a man whose body was pulled from the Blanco; a 14-year-old who was found with his dog in a storm drain; a high school senior who died Saturday after her car was caught in high water; and a man whose mobile home was destroyed by a reported tornado.
A car lies destroyed in front of a house after a tornado struck May 25, 2015 in Ciudad Acuna, northern Mexico, leaving at least 13 dead people and flattening hundreds of homes in a deadly six-second blast of carnage. AFP PHOTO/RAUL LLAMAS (Photo credit should read RAUL LLAMAS/AFP/Getty Images)
The Oklahoma Department of Emergency Management also reported four fatalities between Saturday and Monday after severe flooding and reports of tornadoes.
In Ciudad Acuna, Mayor Evaristo Perez Rivera said 300 people were treated at local hospitals after the twister, and up to 200 homes had been completely destroyed in the city of 125,000 across from Del Rio, Texas.
Thirteen people were confirmed dead — 10 adults and four infants, including one that was ripped from its mother's arms.
Rescuers were looking for four members of a family who were believed missing.
This post has been updated with new information on the flooding, including the number of people unaccounted for.