Gusty winds, high temperatures and low humidity prompted red-flag warnings for the Ventura, San Gabriel and San Fernando valleys.
The warnings expired at 6 p.m. Saturday, according to the National Weather Service (NWS).
A red-flag warning means critical fire conditions are present. Low humidity, high winds and arid brush can rapidly spread fire if a blaze is sparked.
In the Ventura and San Fernando valleys, winds were expected to reach 15 to 25 mph with gusts up to 45 mph in the eastern portion of the Ventura County valleys. Temperatures hovered around 90 degrees and humidity ranged between 6 and 12 percent.
Gusts of 50 mph were reported in the Ventura Hills Saturday morning, according to NWS.
Gusts in the San Gabriel Valley were expected to reach 30 mph, mainly across the eastern foothills.
The relative humidity in that area ranged between 6 and 10 percent, according to NWS. Temperatures in the valley hovered in the mid-90s Saturday afternoon.
A wind advisory is also in effect for Los Angeles County, including the cities of Santa Clarita, Newhall and Valencia, through 6 p.m. Saturday.
A wind advisory means that winds of 35 mph or greater expected. Winds between 10 and 20 mph with gusts up to 40 mph are forecasted.
And because strong winds can make driving difficult, officials urged motorists to be prepared for sudden gusts of wind, especially near canyons and passes.
Still, the Santa Ana winds are expected to leave Southern California by Sunday.
"The good news is, once the winds go away, we're setting up for a lovely evening tonight and a beautiful, even better day tomorrow," said NBC4 forecaster Carl Bell.
An off-coast storm will cool temperatures down everywhere, except the mountains and Inland Empire, next week, Bell said.