Fog Expected to Linger, but Clear Skies Due Sunday

The fog that enshrouded most of the Southland’s coastal and intermediate valleys the last few mornings will probably be back again today, but forecasters say that the overcast should begin moving out on Saturday and that by Sunday the weather should be crisp and clear.

The fog reduced visibility down to 400 feet in parts of Trabuco Canyon Thursday morning, according to the California Highway Patrol.

Fog forced the diversion of several flights from Ontario International Airport before dawn on Wednesday, and at least one flight was diverted on Thursday.

The National Weather Service issued a heavy fog warning Thursday morning for inland highways, especially in the western San Bernardino Valley, but the California Highway Patrol said there was no apparent increase in traffic accidents.

Rick Dittmann, a meteorologist with WeatherData Inc., which provides forecasts for The Times, said the fog has been the result of a stationary low-pressure system stalled off the coast that has been pumping cool, moist marine air inland during the night.

Dittmann said this weather system should begin moving east this morning, bringing with it a “good chance” of light drizzle in coastal, foothill and mountain communities late tonight and early Saturday morning.

The weather system should be well to the east by Sunday morning, which should dawn clear and cool with good visibility, the forecaster said.

High temperatures Sunday should be in the 70s in most Southland areas, a few degrees cooler than today and Sunday.

Thursday’s temperatures around Orange County were Anaheim, 79; Santa Ana, 76; El Toro, 74; Newport Beach, 66, and San Juan Capistrano, 77.

Thursday’s Los Angeles Civic Center high was 76. Relative humidity ranged from 90% to 55%.