Examining the Impact of Climate Change on Heat Waves

In downtown Houston, Texas, pedestrians sought relief in the shade on July 30, 2026, amid an intense regional heat wave. The National Weather Service has issued Extreme Heat Warnings and Heat Advisories affecting over 80 million people this week. The Weather Prediction Center described the current heat dome as an “exceptionally steamy air-mass,” even for mid-to-late August standards.

Record-breaking heat persists across the South-Central U.S., extending to the Southwest by mid-week, with daytime temperatures reaching triple digits. The desert Southwest, including areas in Arizona and New Mexico, faces the potential of setting new heat records, according to the National Weather Service.

As NPR’s senior climate editor, I guide our newsroom during extreme weather events to help understand the influence of climate change. You may seek similar context during these heat threats. We encourage you to inquire about climate change’s impact on extreme weather.

Current Heat Wave Developments

This heat wave is expected to linger over the Southern Plains and Lower Mississippi Valley through mid-week, with temperatures surpassing 100 degrees Fahrenheit. The Southwest will continue heating up, reaching highs of 110 degrees or more by week’s end.

The concern extends beyond daytime heat; nighttime temperatures remain high, offering little relief. Prolonged heat with minimal cooling at night raises the risk of heat-related illnesses.

Scientists increasingly link extreme weather, like heat, to climate change. NPR’s Rebecca Hersher revealed strong climate signals with heat. Michael Wehner, a senior scientist at Lawrence Berkeley National Laboratory, noted average U.S. heat waves experience temperatures 3 to 5 degrees Fahrenheit higher due to climate change.

Journalists rely on trusted sources, such as the National Climate Assessment and the World Weather Attribution network, to report on extreme weather and climate impact. Credible information sources include the National Weather Service and peer-reviewed science. Initial references include:

• National Weather Service maps showing U.S. weather advisories aimed at guiding coverage
• Regularly updated short-range national forecasts

NPR reported substantial funding cuts to NOAA and the National Weather Service under the Trump administration.

Understanding Climate Change’s Role

The connection between climate change and heat waves is well-documented, yet parsing genuine data from misinformation poses challenges. This section links to reliable sources offering peer-reviewed science and NPR’s coverage.

Human-induced climate change exacerbates heat waves, making them more frequent and intense worldwide, with dangerously high temperatures more likely. Journalists emphasize these connections in weather stories.

Climate change, driven by fossil fuel combustion, doubles the average number of heat waves in the U.S. since the 1980s. More frequent record heat results from global warming. Scientists conclude extreme heat waves would be impossible without human-caused warming. For instance, the June extreme heat in Europe would be nearly impossible without human-induced climate change, according to the World Weather Attribution network.

Health Risks Associated with Heat

Daytime temperatures will be sweltering, but focus on the heat index. This metric reflects how relative humidity and air temperature affect human body perception. This week, parts of southern Arizona, Texas, Louisiana, and northern Florida will experience heat indices between 105 and 115 degrees.

Heat-related fatalities are underreported; heat is deadlier than hurricanes, wildfires, and floods combined. Humid heat is particularly hazardous since sweating fails to evaporate, preventing body cooling. NPR’s comic illustrates how extreme heat can lead to death.

Your Contribution

Extreme weather has always existed, but climate change now intensifies and increases its frequency. NPR’s team is dedicated to informing communities about these influences and ongoing efforts. Your inquiries on climate change’s impact on extreme weather can steer future reporting. Share your questions through the form below.

Sadie Babits is NPR’s senior supervising climate editor and author of “Hot Takes: Every Journalist’s Guide to Covering Climate Change.”