Remnants of Tropical Storm Imelda drenched southeast Texas, forcing more than 1,000 rescues and evacuations because of rising floodwaters.
Imelda is largely targeting Houston, the U.S.'s fourth-largest city. Forecasters predict the area will receive more than 100 centimeters of rain this week.
"We're still putting water on top of water,'' said Jeff Linder, meteorologist of the Harris County Flood Control District.
The heavy rains grounded flights Thursday and brought George Bush Intercontinental Airport to a halt. According to the Federal Aviation Administration, the airport was not expected to reopen until Friday.
All public transportation was shut down in the Houston metro area, and city officials asked residents to avoid driving and stay indoors.
The National Weather Service has issued a flash flood warning for several counties from Houston to the Louisiana state border.
Imelda has weakened to a tropical depression since making landfall Tuesday near Freeport, Texas, with maximum sustained winds of 64 kilometers per hour.
Imelda is the first named storm to inundate Houston since Harvey hovered over the city for several days in August 2017, dumping nearly 130 centimeters of rain in some areas.