Signals from La Niña suggest we’re in for a hot fall, with more long heat waves like the one that just blanketed the West Coast in record highs.

The extreme temperatures weren’t unexpected to climate scientists, though maybe they came as a shock to the general public, said UCLA atmospheric scientist and statistician Karen McKinnon.

• “This is what we were predicting, but now it’s what we’re feeling in everyday life.”
• “The recent heat dome isn’t unexpected under climate change, but it shows us how a few degrees make a big difference. We are all experiencing what summer extremes look like, even with what may seem like a modest level of warming. At the extremes, it doesn’t feel like a modest level of warming.”
• “If your summertime temperatures are 4° F warmer than 50 years ago, your typical summer day might go from 84° F to 88° F, and you won’t really notice. But when your extreme summer temperatures go from 98° F to 102° F, the impacts start to pile up because our bodies are sensitive to those temperatures. On a mild summer day, no one notices climate change. The only times we notice are at the extremes.”
• “We were living through a climate change extreme during the last heatwave. Across the board, the average daily high and low temperatures are higher. With climate change making everything warmer, by definition the heatwaves get longer.” 

Media are encouraged to quote from McKinnon’s comments or reach out for additional comments from her or other UCLA wildfire and climate experts.

Katherine McKinnon is an associate professor studying climate extremes and large-scale climate variability at UCLA’s Department of Statistics and the UCLA Institute of the Environment and Sustainability.