word of the worsening conditions in the west as a powerful system makes its mort. A a mud slide north of San Francisco, just the latest emergency call. The images coming in, trees down and damage from... See More
word of the worsening conditions in the west as a powerful system makes its mort. A a mud slide north of San Francisco, just the latest emergency call. The images coming in, trees down and damage from the powerful storm hitting several states. This car flipped over. So many accidents in the snow. And from Utah, the frantic rescue effort after an avalanche. A young woman trapped under the snow for more than 40 minutes. Tonight, two new systems we're watching. The forecast in a moment here, but we lead off with ABC's Clayton Sandell. Reporter: Tonight, winter is whipping the west with floods, mud slides and avalanches. It is snowing in Seattle. The streets of San Francisco are surging. Trees are taking out cars and cars are taking down power lines. It's so icy in Portland, Oregon, they're sending out cell phone alerts warning people to stay inside. In Utah, 21-year-old Ashley cox rushed to a hospital in extremely critical condition. Swept away by an avalanche Saturday while snowshoeing. She was trapped for 40 minutes. Normally, the chances of surviving rapidly drop after just 15 minutes. As we recently learned when I was buried during an avalanche drill. One of the extra dangers for an avalanche victim is that when you exhale, your warm breath actually melts the snow immediately around you, and then that refreezes, which just traps all of the carbon dioxide that you're exhaling and makes it even more difficult to get oxygen. And in addition to snow, a foot of rain in northern California is kicking loose rock and mud slides. Roadway is slugging off. There was one house in jeopardy that we evacuated. Reporter: The storm will be pushing east after helping raise the water level in this California reservoir nearly four feet. Not enough to make much of a dent in the west's epic drought, but a welcome start. Clayton Sandell, ABC news, Denver. Clayton, thank you. The pictures from the west tonight. While in the middle of this country and in the east, millions are bracing for a Monday morning commute tomorrow with wind chills as low as 40 below. Look at this tonight, a before and after from this winter to remember. The great Lakes right here in warmer times, the five of them there in the heart of summer. Tonight, though, the view many of those Lakes hard to make out because more than three quarters of them are now covered in ice. Scientists now monitoring them say they're 78% frozen over. That's the most in nearly two decades. I want to bring in Julie Durda of ABC station WPLG with us again tonight. The temperatures tomorrow morning are going to keep the Lakes frozen in place. It is going to be brutal. It's been a horrible winter with the wind chill factor. Again, we're dealing with very cold conditions. Wind chill advisories across the midwest. Expecting temperatures to be 21 degrees below zero, Chicago. And that cold, arctic air spills all the way down to the southeast. 13 degrees in Little Rock and Nashville. A very cold start to the week here. You are tracking a storm system Monday into Tuesday. Yes, this is going to be another winter storm that's going cause some chaos for your fries across the gulf coast states tomorrow. Says we watch this low developing, we will see the possibility of freezing ice and snow for parts of the southeast, anywhere from Mississippi all the way into the Carolinas. The worst of the weather will probably be the Tuesday morning commute. We have winter weather advisories in effect across the southeast, as snow, sleet is going to be a big issue from our friends from Mississippi all the way into the Carolinas. Julie, thank you. Going to make for some difficult
This transcript has been automatically generated and may not be 100% accurate.