Flooding Traps People In Cars, Businesses As Brutal Storm Hits Southwest

A drastic swing in the weather is creating dangerous flooding for millions of Americans.

At least 13 million people between Arizona and Louisiana are on alert for flooding at the start of the work week as a monsoon storm system hammers the drought-stricken region.

Torrential rain poured across north Texas overnight, flooding streets and prompting some water rescues overnight in the Dallas-Fort Worth area, CBS News correspondent Omar Villafranca reported Monday.

This comes after the storm system slammed Utah, where floodwaters rushed through the streets and forced people to carry children out of washed-out businesses. As patrons pushed their way out of knee-deep water in partially submerged restaurants, others drove their vehicles through flooded streets.

Also in Utah, rescue crews were searching for a missing hiker who may have been swept away by the water. Authorities worried 29-year-old Jetal Agnihotri of Tucson, Arizona, may have drowned.

The U.S. Park Police received reports of multiple hikers being swept off their feet by floodwaters in the region. A cellphone video showed an unidentified person clinging to a log as the floodwaters rushed past a group of hikers in Utah. 

In New Mexico, more than 100 park-goers were trapped for several hours at a visitor's center in Carlsbad Caverns National Park, before eventually being escorted out.

Firefighters are leaning on the rain to help combat wildfires brought on by a historic drought this summer. But those dry conditions have hardened the soil, creating a cement-like foundation for floodwaters to rise.

A few people were trapped in their cars on Interstate 30 in downtown Dallas as the water quickly rose around them. The water soaked and submerged a few cars and even stopped traffic. 

Dallas saw more than 6.5 inches of rain in 24 hours, The Weather Channel's Jim Cantore said Monday on "CBS Mornings." In just one hour, the city had 3 inches of rain, the most rain Dallas has seen in a one-hour period since at least 1953, he said.

The heavy rain follows weeks of dry weather. 

"The tables have turned big time," Cantore said. "As a matter of fact, this is probably the wettest August on record for Dallas."

As crews work to clear the roads, more flooding is expected from northeast Texas to Mississippi.

"We'll watch this flood threat continue through today, through tomorrow and into tomorrow night," Cantore said.