More than 90 million Americans are under heat advisories this week.

In the West, where a record-breaking heat wave is expected to be long lasting,

firefighters are working to extinguish several major wildfires, forcing thousands of Californians to

evacuate.

All of this comes as President Biden unveiled long-awaited regulations designed to protect

workers from excessive heat.

Stephanie Sime has more. Stephanie?

Um, now many people may not realize it, but heat is the leading cause of weather-related death in the U.S.

As many braced for triple digits in the days ahead, protection from extreme heat is top of

mind for many.

Haley Smith is an environmental reporter with the Los Angeles Times

and has been covering all this closely.

Haley, it's good to see you.

You know, it seems every July, more heat records are shattered, and yet I've seen a lot of

superlative language around what's facing Central and Northern California this week.

Why is this heat wave so concerning?

Hi, I think it's for two reasons.

One is that this is not only a severe heat event,

but it's also a prolonged event.

We've got excessive heat warnings in effect,

basically from the far northern counties of California

all the way down to the Mexican border. Portions of the Coachella Valley are going. the 15 degrees, even 110 here in some parts of Los Angeles.

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