New Interactive Map Shows Where Extreme Heat Threatens Health

People in the U.S. will be able to see where extreme heat is a threat to health with a new interactive tool created by the National Weather Service and the Centers for Disease Control and Prevention

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A woman shades herself from the sun with an umbrella as she walks on the National Mall during warm weather in Washington, D.C.

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CLIMATEWIRE | An online tool launched Monday by the Biden administration aims to keep people safe from extreme heat by showing them where in the lower 48 states temperatures are high enough to harm their health.

The interactive map, called HeatRisk, appears on websites for both the National Weather Service and the Centers for Disease Control and Prevention.

Users can scroll through to look at current heat conditions, as well as a forecast for the next several days. The map is color-coded to show the risk of heat-related health impacts — with green being little to no risk and magenta showing areas of extreme heat health impacts.


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“We know heat can impact our health, but heat-related illness and death are preventable,” CDC Director Mandy Cohen said at a press conference Monday.

The color-coding of the maps is based on local health data that reflects actual increases in emergency department visits at different temperatures.

The CDC’s version of the dashboard also directs visitors to guidelines on heat risk and how to stay safe in high temperatures. Its release came the same day the CDC put out new guidance for clinicians for how to help vulnerable patients — such as those with heart or lung conditions — handle extreme heat conditions.

“We see this as a real watershed for our ability to achieve our mission at CDC, which is to protect health and improve lives,” National Center for Environmental Health Director Ari Bernstein said. “For the first time, we will be able to know how hot is too hot for health, and not just today but for the coming weeks.”

The National Weather Service in 2013 had launched a prototype tool of the same name covering only California. That tool then was expanded to the western United States in 2017.

But this is the first year the tool will exist for the entire continental United States. It’s also the first year it includes information about the impact of heat on health.

“Heat waves are getting hotter, longer, more frequent and you’re getting less relief at night, so it’s becoming increasingly serious,” National Weather Service Director Ken Graham said.

At the moment, the HeatRisk tool is being billed as “experimental,” but Graham said NWS is hoping to get feedback from the public, including emergency managers and meteorologists, about ways to improve it.

That also means NWS heat advisories will remain unchanged for now. But Graham said the new tool could “fuel ways that we issue some of those products” down the road.

“And that’s exciting, because you want as much science in there as possible,” he said.

Reprinted from E&E News with permission from POLITICO, LLC. Copyright 2024. E&E News provides essential news for energy and environment professionals.

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