Heat wave to bake Southern California on Saturday

An oppressive four-day heat-wave sizzling throughout Southern California signals the transition from a hot summer to the beginning of a Santa Ana season that weather experts fear could trigger massive wildfires.

Saturday will be the peak of the high temperatures, with some places seeing temperatures as high as 106 degrees. The heat waves comes during what is usually the beginning of the Santa Ana season, when gusting winds can further dry out already dry vegetation and lash forward any fires that break out.


The winds are expected to be relatively weak this weekend, but if strong Santa Anas arrive before any unexpected rains, the risk of large fires would be great.

“This is a preview of an early Santa Ana season and this is bad,” said Bill Patzert, a climatologist for the Jet Propulsion Laboratory in La Cañada Flintridge. “Triple-digit temperature, single-digit humidities and gusty breezes—that’s a formula for misery and fires.”

A high-pressure weather system combined with offshore winds and warm but weak Santa Ana winds have combined to generate the hot weather, said Stuart Seto of the National Weather Service. The winds sink as they travel through the mountains, then they are compressed and warmed up as they move toward the coast, he said. So in addition to heating up the area, they also block the coastal sea breeze that usually cools the seaside areas, Seto said.  

Sweltering heat forced Long Beach Unified School District to shorten school days Thursday and Friday since most campuses are not equipped with air conditioning.

And Los Angeles Unified canceled all outdoor activities and sports practices for Thursday and Friday in the San Fernando Valley because of the heat.

The hot temperatures, low humidity and windy conditions prompted the U.S. Forest Service to implement 24-hour firefighter staffing as officials issued red flag warnings across the Southland. Those warnings are expected to expire Friday evening at 7, Seto said.

On Sunday, temperatures will begin to drop, and by Wednesday, the region will return to more typical weather: mid-70s at the beaches, lower 80s inland.

Twitter: @MattStevensLAT |