L.A. heat wave will spike Saturday; fire danger heightened

Saturday is going to be the hottest day of Southern California’s heat wave, with temperatures passing 100 degrees in some areas and rising to the 90s even in some coastal locations.

A slight cooling trend is set for Sunday, according to the National Weather Service.

The spike in temperatures comes during what is usually the beginning of the Santa Ana season, when gusting winds can dry out already desiccated vegetation and whip small fires into monsters. There were several small brush fires reported Friday.

“This is not a good preview of coming attractions,” said William Patzert, a climatologist for the Jet Propulsion Laboratory in La Cañada Flintridge. “Triple-digit temperature, single-digit humidity and gusty breezes — that’s a formula for misery and fires.”


If there’s an upside, it’s that this weekend’s winds will not be too strong, said Patzert, calling them “Santa Ana Lite.” But they’re strong enough to play a starring role in the Southland heat wave.

A high-pressure system combined with weak Santa Ana winds has generated the hot weather, said Stuart Seto of the National Weather Service. The winds sink as they blow through the mountains, then compress and warm up as they move toward the coast, he said. So in addition to heating the area, the winds block the sea breezes that usually cool coastal communities.