California this week endured one of its longest and most intense September heatwaves, smashing temperature records up and down the state.
Since 1 September, more than a dozen cities across the state set new all-time highs, with numerous others tying previous records or setting new monthly records. Thermometers in Sacramento, California, recorded a stunning 116F (47C) on Tuesday.
Other states in the American west were not spared either. Temperatures in Reno, Nevada, reached 106F (41C) this week, while Salt Lake City, Utah, registered 107F (42C).
Scientists say the blistering week underscores an alarming new reality: heatwaves are getting bigger, longer and extend across larger swaths of land.
“By mid-century, the spacial size of heatwaves in the US are expected to increase between about 50% to 80% from what they are in the current climate,” said Bradfield Lyon, a professor at the Climate Change Institute at the University of Maine. “The frequency will increase, the duration will increase, as well as the intensity.”
Here’s a look at some of the records that were shattered across the US west this week, from San Diego to the San Francisco Bay area and beyond.