A long heat wave is settling in across most of California, threatening wildfires and raising public health risks that include the spread of COVID-19 over the next week.
It's not a dry heat, either. Temperatures will feel worse than usual, especially overnight, as a result of an unusual boost in atmospheric humidity caused by the remnants of a hurricane.
On Friday, high temperatures around the Bay Area included 109 in Fairfield, 103 in Petaluma and 103 in Santa Rosa, according to the National Weather Service.
Climatologist Daniel Swain says some coastal areas will escape the most unbearable temperatures, but that heat will blanket 90% of California's land mass, so most people should get ready.
“I suspect this event will probably end up being one of the most significant widespread California extreme heat events in the past decade, if not longer,” writes Swain on his Weather West blog.