What Is HeatRisk? New Interactive Map Shows Where Heat Is Reaching Dangerous Temperatures

The Biden administration launched a new online tool in April with the intention of keeping people safe from extreme heat. The new interactive map, called HeatRisk, which appears on both the National Weather Service and Centers for Disease Control and Prevention websites, shows where in the Lower 48 states temperatures are reaching dangerous levels.

The map shows current heat conditions as well as the forecast over several days. Color coding, based on local health data reflecting real increases in emergency department visits, shows the level of risk: Green means little to no risk, while magenta indicates areas of extreme heat with dangerous health impacts.

(​MORE: Long-Duration Heat Wave To Break Daily Temperature Records)

“Extreme heat might not grab headlines like hurricanes, tornadoes and winter storms, but it's America's top weather killer annually,” said weather.com senior meteorologist Chris Dolce. “Heat has killed an average of 188 people in the U.S. over the past 10 years, according to NOAA statistics.”

The CDC’s dashboard includes guidelines on heat risk and safety in high temperatures.

“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 map was unveiled on April 22, the same day that the CDC put out new guidance for the medical industry for treating vulnerable patients during extreme heat.

“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 told Scientific American.

A prototype of the map was released in 2013 covering only California, then expanded to cover the western U.S. in 2017. This is the first time the map includes information for the entire country. It’s an “experimental” endeavor, and the NWS is seeking feedback from the public and experts on ways to improve the dashboard.