Mid-October heat wave rises in Southern California, increasing fire risk

A warming trend will slowly build up across Southern California this week, with much of the region expected to see above-average highs through at least Friday, forecasts show.

Temperatures are expected to climb a few degrees each day until peaking Thursday, with highs reaching up to 15 degrees above normal for this time of year.

“Our typical natural air conditioning in being turned down this week,” said Mike Wofford, a National Weather Service meteorologist in Oxnard. “A lot of the cool air is staying over the ocean and not moving in to cool us off.”

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Temperatures will be up to 15 degrees above normal this week, peaking Wednesday and Thursday, with a heat advisory for the Bay Area before a cool trend Friday.

Oct. 19, 2023

Monday’s highs are expected to be about five to 10 degrees above average, reaching 85 degrees in downtown Los Angeles.

By Thursday, the valleys are forecast to see highs in the 90s, with downtown L.A. in the low 90s, the beaches in the 80s and low deserts above 100.

Typically this time of year, downtown peaks at just under 80 degrees, Wofford said.

Though this week there won’t be dry, westward Santa Ana winds that often hit this time of year, Wofford said the warming is caused by a similar pattern.

“We’re getting some of the beginnings of [the Santa Anas], with offshore flow,” he said. “It’s going to be warmer all week.”

The above-average temperatures won’t amount to especially dangerous heat, but the conditions will create a “general risk” for wildfires, he said.

“It’s going to be hot and the humidity is going to be low,” Wofford said. There’s an “elevated risk [of fire] but it’s not extreme. We’re not having the big winds with this one.”