Strong gusty west winds will bear sweep the mountains and deserts of San Diego County late tonight as a cold front out of the Gulf of Alaska bears down on the region, forecasters said.
The National Weather Service scheduled a wind advisory for mountain and desert areas from midnight Thursday to 3 a.m. Saturday. During the advisory period, residents can expect west winds of 20 to 30 miles per hour, gusting up to 55 mph, NWS forecasters said.
Winds are expected to be strongest near ridge tops, along desert mountain slopes and in adjacent desert areas.
"The winds will make driving difficult, especially for motorists with high- profile vehicles," according to an NWS advisory. "Watch for broken tree limbs and downed power lines. In the deserts, areas of blowing dust and sand could reduce visibility at times."
The cold front out of the Gulf of Alaska began shifting southward on Tuesday. The bulk of the low pressure system will arrive in San Diego County late Thursday, according to the Weather Service, which forecast much cooler temperatures, showers and snow in the mountains heading into the weekend.
Highs on Friday are expected to be in the 50s and 60s at lower elevations, and in the 30s and 40s in the mountains.
"These high temperatures will be 25 to 35 degrees cooler than high temperatures early this week," according to the Weather Service.
A tenth- to a quarter-inch of rainfall is expected near the coast Friday, while around a half-inch is possible in the mountains. Less than a tenth of an inch will fall in the deserts, forecasters said.
The main periods of precipitation are expected late Thursday night through early Friday and again Friday night.
"A few showers could linger over southern coastal areas into early Saturday morning and near the mountains into Saturday afternoon," according to the NWS.
The snow level is expected to drop to 4,000 to 4,500 feet Friday afternoon and to 3,000 to 3,500 feet Friday night into Saturday. Forecasters said a few inches of snowfall is possible above 4,000 feet, and local amounts of around six inches could fall on the county's highest peaks.