Heat Dome Grips the West: What Is It, and How Can It Affect Health?

What is a heat dome and why is Colorado about to experience one?

A heat dome happens when strong high pressure traps hot air over a region for several days, causing prolonged and sometimes dangerous temperatures. As global temperatures rise, we’re entering an era of weather disruption, sometimes called “global weirding,” a term popularized by climate scientist Katharine Hayhoe. Extra heat in the atmosphere adds energy to weather systems and pushes conditions into unstable and historically unprecedented territory.

Is this heat dome part of the “new normal?”

In many ways, yes. As the effects of climate change accumulate, extreme heat events are becoming more frequent and more intense. What used to be considered unusual heat is increasingly becoming part of our seasonal weather patterns.

Why is extreme heat such a serious health risk?

Extreme heat is one of the most dangerous weather hazards because it increases hospital admissions and deaths. Heat stress can worsen heart disease, lung disease and kidney problems, and heat stroke is life-threatening.

Who is most vulnerable during a heat wave?

Older adults, young children, outdoor workers, people with chronic illness and those without reliable access to air conditioning are most at risk. Heat and wildfire smoke can also worsen air quality, which can trigger asthma attacks and other respiratory problems.

What should Coloradans (and those in other states) do to stay safe during the heat dome?

The most important steps are staying hydrated, limiting outdoor activity during the hottest part of the day and seeking cool or air-conditioned spaces whenever possible. It’s also important to check on neighbors, especially older adults or people living alone because heat affects communities unevenly.

How can extreme weather like heat affect hospitals and healthcare systems?

Heat waves increase emergency department visits and hospitalizations. More broadly, climate-driven disasters, from wildfires to tropical cyclones, have already forced safety-net hospitals in major American cities to close temporarily. That highlights the need to build more resilient healthcare systems that can continue delivering care during extreme events.

What is CU Anschutz doing to address climate-related health risks?

The University of Colorado Anschutz Climate & Health Program launched the field of climate medicine in 2017. Our clinicians track how climate impacts human health and help healthcare systems prepare for threats such as extreme heat, wildfire smoke, infectious disease spread and severe weather.