Transcript for Flash flooding reaches areas damaged by wildfire
are also watching a major storm system already creating chaos tonight, sweeping from the west, into the midwest and northeast. Dangerous driving and accidents across southern California already. Semitrucks jackknifing and sliding off the highways a chaotic scene. Traffic at a standstill in the rain. As I mentioned, that severe weather headed to the northeast eventually. And we have the new track tonight. ABC's will Carr in California. Reporter: Tonight, a bone dry region thirsty for rain, getting too much too quickly. The weather creating havoc on California highways. A big rig slamming into two cars before sliding off the side of the freeway and down an embankment. Four firefighters hurt in a crash after a driver spun out on a slick road and smashed into their truck. Overnight, tractor trailers jackknifed and crushed. This car flipped over. The driver rushed to the hospital. Traffic snarled for miles. And watch first responders make a daring swift water rescue on the L.A. River. Tonight, mudslides also rushing across areas recently ravaged by wildfires. Just a lot of mud coming down at a very rapid rate of speed now here in rice canyon. Reporter: Evacuations now underway in butte county. This man riding his horses to safety, not far from the city of paradise, the community wiped off the map from the camp fire. So, let's get to will Carr, joining us from California. Will, I know that there's still a risk of mudslides made even worse because of the fires that simply cleaned away the landscape. Reporter: David, with more rain on the way, all eyes are on the burn scars, because there are no trees to stop all of that rock and mud from rushing down and slamming into homes that are still standing and communities like this that have before been devastated. David? Certainly don't deserve this. Will, thank you. Let's get right to rob Marciano, tracking it all as the system moving from the west all the way across the country, rob. Reporter: That's right, David. It's a potent pacific system, going to impact the entire U.S. California getting the worst of it right now. And there's another storm behind it. An active pattern. Tonight, heavy rain, imbedded thunderstorms, wind and heavy mountain snow. It is moving quickly. By tomorrow night, it's already in the plains. After that, a severe weather component. Dallas to Little Rock to new Orleans. Big-time hail, big wind, maybe tornadoes pushing across the gulf coast. Heavy snow in Nebraska. And heavy rain moving into the northeast by Saturday night. David? A very messy week ahead. Rob, thank you. As you all know at home, we
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