Transcript for Yosemite National Park Wildfires Continue to Spread
We want to get to the top story this morning, the wildfire raging into yosemite national park. Morning, it's threatening homes as well as the city of san francisco's water and power supply in a state of emergency. We start the coverage with abc's neil karlinsky in yosemite national park. Neil. Reporter: Good morning. A bit of good news this morning, the fire is not growing larger, and critically, it is now 7% contained. A steady move in the right direction. The unseen war against the fire. Teams set backfires overnight, hoping to burn up fuel in the way of the rim fire while the wind is down in order to stop it from growing once day breaks. This is what they're trying to protect, yosemite. A national treasure that draws millions of tourists from around the world. So far, it's working. We spent time with fire teams inside yosemite, far from the mountains and water falls which make it famous and which remain open and untouched. But they have concerns about the giant sequoia trees, three dozen are in the burn zone, and teams are giving them special attention to protect them. We want to stop it from getting worse. So if it picks up in intensity, we keep it from crossing the road. Reporter: While they hold the fire at bay, a state of emergency is in effect for san francisco, 150 miles away because power lines have been threatened by the huge blaze and more. This is one reason for the emergency decklation, this reservoir, they are worried about the water being polluted by all this ash coming down. Meanwhile, tourists are not l letting the fire stop them. This family from the uk is surprised, but determined to take a detour and visit yosemite anyway. It was the last thing we expected. It's a bit strange. Nothing like this happens at home. It's a bit bizarre. We had no idea it was going to be like this. Yeah. Reporter: So many resources have been put on this fire, both in the air and on the ground, fingers crossed, but officials are finally beginning to get the sense they are getting a handle on it. Dan. Fingers crossed. Just to show how big it is, it's creating its own weather. Ginger zee is here with details and incredible new pictures. Good morning. Overall weather pattern has been consistent. It's within the fire with the huge flames and intense heat, come with me, that heat goes up into the cooler atmosphere and create its own cloud, a pyro cumulus cloud. The air has to come down and hit the ground, rushes out, and the flames become more erratic. That's the rim fire, but there are so many other fires along the stationary front. That's going to create thunderstorms, lightning and the erratic wind. The fire forecast not looking good. And the flooding later. Thank you. We'll see you in a few minutes. And rebecca jarvis is in this
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