The storm, the second fatal one to strike the region in 11 days, spawned several tornadoes, toppled cars and left commuters trapped on an interstate highway during Friday's evening rush. Law enforcement officers and Red Cross workers headed to hard-hit areas after dawn to assess the damage.
The storm also brought heavy rain and hail.Floodwaters topped 4 feet in Oklahoma City early Saturday and were expected to rise as flash flooding continued in parts of the state. Across east and central Oklahoma, repeated rounds of thunderstorms have produced between 4 to 7 inches of rain since midnight Saturday.
Some highways were closed because of downed power lines. The Oklahoma Corporation Commission reported more than 91,800 power outages related to the storms as of Saturday afternoon.
The area along the state's I-40 corridor, packed with motorists when the storm occurred Friday, was particularly hard-hit. The nine deaths included seven adults and two children. A mother and a child were killed when their car rolled over, KFOR-TV reported.