Torrential rain left much of central Texas swamped Tuesday after savage weather killed at least 28 people in the United States and Mexico, and Houston's mayor warned more deadly flooding could be in store.
People were trapped in their cars, others marooned in their homes, as flood waters rose menacingly around them. Two people died overnight due to the flooding in the city, Mayor Annise Parker said.
A savage twister roared through the border city of Ciudad Acuna at dawn Monday, killing at least 13 people and flattening hundreds of homes in a deadly six-second blast.
Texas authorities said 13 people have been killed across the sprawling state in the weekend storms, at least four of them in Houston. Fears were growing meanwhile for at least 11 people still missing in Hays County, also in Texas.
Many of the dozen missing in Hays County were from one house that was torn from its foundations during a terrifying flash flood over the weekend.
Hundreds of vehicles, some fully under water, were abandoned on Houston's roads.
The southern US states of Texas and Oklahoma, and northern Mexico, have borne the brunt of several days of violent weather, including tornadoes, which have left scores dead, missing and injured on both sides of the border.
Houston brought to standstill as rains wreak havoc