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The weird wind that can supercharge heatwaves and wildfire
Hot "hairdryer" winds that whip down mountainsides play a role in devastating heatwaves and wildfires – and they may become more of a problem with climate change.
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Strange hot, dry winds that blow down mountainsides can desiccate vegetation and fan wildfires. Credit: Getty Images |
It's a word that, in German, also means "hairdryer". And that's just what it's like. A hot, dry wind that sweeps down a mountainside, baking everything in its path. It is powerful enough to raise air temperatures by many degrees. This is the strange, and sometimes dangerous, weather event known as Föhn.
These winds – sometimes known as Santa Ana winds in California – often crop up during heatwaves, where they can push temperatures up to unbearable levels in local, literal, hotspots. In the right conditions they can also fan flames into raging wildfires.
In January 2025, a powerful Santa Ana windstorm with gusts forecast to reach up to 100mph (160km/h) swept over southern California. The winds, which the National Weather Service described as "life threatening", fanned flames that started in the mountainsides to the west of Los Angeles into a fast-moving wildfire that spread through already dry vegetation to engulf the Pacific Palisades neighbourhood near Santa Monica, forcing at least 30,000 residents to evacuate. [continue]