Colorado sees dangerous heat waves increase
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The two largest cities in Colorado are getting more heat streaks, raising health risks for residents, a new analysis finds.
The big picture: Denver and Colorado Springs both had four additional heat streaks on average between 1970 and 2024, per a new report from research group Climate Central.
- Nearly 200 U.S. cities recorded more heat waves. Some areas, including Nashville, Tennessee, and Raleigh, North Carolina, now see a whopping five more heat streaks on average each year.
Why it matters: Prolonged heat — which much of the U.S. has experienced this summer — is particularly hazardous to human health.
- The effects of extreme heat on the body tend to be cumulative, and warm nights offer little reprieve for those without air conditioning.
- Multiday heat streaks are also challenging for power grid operators and can worsen air quality.
By the numbers: The average number of annual extreme heat streaks rose in 80% of the 247 U.S. cities analyzed in the Climate Central report.
State of play: While this week may not register any heat waves, Denver's particular brand of sporadic weather will be on full display.
- Incoming storms could prompt flash floods, per the National Weather Service, just one day after 90-degree temperatures engulfed the metro area.
The latest: Tuesday got off to a historically muggy start in Denver, with the city recording its highest dew point in 17 years — an indicator of potentially severe weather, according to 9News.
How it works: Climate Central defines an "extreme heat streak" as three or more consecutive days with maximum temperatures over the 90th percentile of the daily max temperatures of a given location.
Between the lines: Climate change is making extreme heat more intense and more frequent, studies have shown.
- Many urban neighborhoods, including several in Denver, face the "urban heat island" phenomenon, where buildings, roads and other structures trap heat, making it even hotter.