Now let's focus on the dangers of extreme heat, which is considered the leading weather-related

cause of death in the United States. Local officials are warning people to take precautions,

including in Chicago, where the heat is expected to get serious tomorrow. Mayor Brandon Johnson

warned about the health risks and recalled a deadly heat wave the city experienced in 1995.

Chicago knows better than any other city in America the danger of extreme weather, particularly extreme heat.

In fact, we are one month away from the 30-year anniversary of the 1995 heat wave, the deadliest heat wave in American history.

We lost more than 700 Chicagoans. Most of them were the elderly and the poor.

It really challenged the city to recognize the danger of extreme heat so that we never see a tragedy like that

occur again.

For more on those dangers and key tips for dealing with the heat, we turn to Ashley Ward,

director of the Heat Policy Innovation Hub at Duke University.

Ashley, thank you so much for joining us.

So we just heard from the mayor of Chicago reminding us that the elderly and the poor were particularly vulnerable in that heat wave of 95.

Talk to us about what factors go into certain groups being at greater risk and what can be learned from previous deadly heat waves.

Sure.

I mean, certainly our age populations, children, the poor, as the mayor

pointed out, but also pregnant women. In many of these cases, what's happening is the body's

ability to thermoregulate is not as efficient as it once was when someone was younger. If you're

a child, not quite as efficient as it will be. And so as you get exposed to heat, your body's having to work

harder to keep your core body temperature at safe levels. But also, many of the people in these

vulnerable groups suffer from other underlying chronic conditions like cardiovascular disease

or respiratory renal diseases, which also make it harder for your body to

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