NWS, CDC collaborate on HeatRisk tool to provide health guidance

HeatRisk provides context for heat, taking into account cumulative impacts on those most susceptible

ROANOKE, Va. – Ask anyone in the weather forecasting industry, and they’ll tell you that there’s been a more focused effort on communicating weather impacts instead of just numbers.

One such example is HeatRisk, a collaboration between the National Weather Service and the Centers for Disease Control. HeatRisk was first developed as a prototype for California in 2013 before expanding into the Western U.S. four years later.

It “provides information and guidance for those who are particularly vulnerable to heat,” according to NOAA.

After all, heat has been the number one weather-related killer in the U.S. for at least the last 30 years.

Weather-related fatalities on average from 1993 to 2022.

By identifying how unusually hot it will be, the duration of the heat and the time of year (among other parameters), a five-tier scale has been devised to assess the threat heat poses to those most vulnerable.

The forecast goes seven days in advance.

Here is how HeatRisk is calculated

A more detailed breakdown of the HeatRisk shows the difference between a 0 (No Risk) and a 4 (Extreme Risk).

The five-tier HeatRisk explained in more detail.

This graphic posted by the National Weather Service dives deeper into what we posted above, showing the meaning, who’s at risk, the commonality of heat and preventative actions.

Heat risk diagram posted by the National Weather Service.

CDC Director, Mandy Cohen, says, “We are releasing new heat and health tools and guidance to help people take simple steps to stay safe in the heat.”

This may all seem far-fetched for us, but you can see the trend in heat in our area when you break down the average number of 90° days in Roanoke.

90° heat has been on the upswing in recent years in the Roanoke Valley.

Combine that with the fact that parts of the city tend to be an urban heat island, and you can see why HeatRisk might be useful.

Looking ahead at late April, when we’ll be warmer, you can see how there’s a ‘Minor’ HeatRisk in our area.

A 'Minor' HeatRisk is forecast for Monday, April 29, 2024.

The National Oceanic and Atmospheric Administration says that this tool will be used in conjunction with, or as a compliment to, the Heat Index or Wet Bulb Globe Temperature.

Although we’re far off from the hottest time of year, it’s important to note the difference between heat exhaustion and heat stroke.

Heat exhaustion vs. heat stroke

[DOWNLOAD OUR WEATHER APP here to stay on top of the latest temperature trends.]

About the Author

Meteorologist Chris Michaels is an American Meteorological Society (AMS) Certified Broadcaster, forecasting weather conditions in southwest Virginia on WSLS 10 News from 5 a.m. to 7 a.m. weekdays on Virginia Today.

Recommended Videos