Transcript for Tens of millions experience sweltering temperatures, heat wave
We turn now to the historic heat wave not just in the west, across ten states from California to Iowa. Here's Matt Gutman tonight. Reporter: Tonight, the dome of heat melting the west is expanding and shattering records as it spreads. Tens of millions of Americans sweltering in temperatures above 100 degrees for multiple days, and it's still technically spring. Electrical grids strained to the max. And the Dallas skyline darkened. Utility companies from Texas to California are begging people to set thermostats at 78 degrees and to brace for possible blackouts. We're making sure we have enough crews on standby and we're ready in case we do experience those outages. Reporter: For people die from extreme heat than any other type of extreme weather. In maricopa county, Arizona, last year, a record 323 people died because of high temperatures. Doctors warning hot pavement, even sand, could bring third-degree burns. Experts say climate change is making heat waves more intense, more frequent, and longer lasting. It's also supercharging the megadrought that's drying up Lakes and rservoirs that millions rely on for their water supply. This time a year ago this dock would've been about 30 feet under water. It's now high and dry. And Folsom lake has shrunk so much that to get to water's edge you've got to two a quarter mile in that direction. Those low lake levels even making it possible to find the wreckage of a 1986 plane crash using sonar technology. It could be six months before you get any measurable rain. Yes. Reporter: What's that lake going to look like in December then? I don't know. We'll probably just see a river with a small pool in front of the dam. Reporter: David, state officials here tell me that even their models failed to predict how significant this drought would be and how much reservoirs and Lakes like the one behind me would shrink. One official telling me it wasn't even close. David. Just extraordinary pictures. They really do tell the story.
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