Heavy rains in San Antonio rapidly flooded roads, swept away submerged cars and sent some people scrambling up trees to escape fast-rising waters Thursday while firefighters made dozens of rescues across the nation’s seventh-largest city.

The San Antonio Fire Department told CBS News on Saturday that 13 people have been found dead after flooding on highways in Texas.

The National Weather Service says five to seven inches of rain fell in just three hours, more than most urban drainage systems can handle.