National Weather Service Issues Winter Storm Warning

A National Weather Service wind advisory for the mountains and deserts in eastern San Diego County is in effect until 10 p.m. Christmas Eve. Winds of 25 to 35 miles per hour are expected, along with gusts of 55 to 65 mph.

Forecasters said while winds would begin to ramp up during the afternoon hours Friday, a second and stronger bout is expected Saturday afternoon through Saturday night.

"A low pressure system from the northwest will bring stronger onshore flow with periods of strong gusty west winds in the mountains and deserts through late Saturday night," according to the weather service.

Related: Sheriff’s Department Preparing For Snow In Local Mountains

A winter storm warning for mountain locations higher than 3,500 feet will run until 3 a.m. Christmas Day. The snow level is expected hover around 3,500 feet Saturday afternoon and evening.

Forecasters said there would be a chance of rain during the day today, but it "will be dwarfed by the heavy rain that will fall" later in the day.

Forecasters predicted that through Saturday the storm would drop 4 to 6 inches of snow in Julian and 8 to 12 inches on Palomar Mountain and Mount Laguna. Rainfall amounts expected through Saturday were 2.39 inches on Palomar Mountain; 2.22 in Julian; 1.93 on Mount Laguna; 1.60 in the Miramar area; 1.57 in Escondido; 1.56 in Alpine; 1.48 in Ramona; 1.47 in Oceanside; and 1.40 in San Diego.

The storm is expected to move out of the region Saturday night and milder and drier weather will follow on Christmas Day, forecasters said.

A slight chance of thunderstorms is also in the forecast throughout the county. A brief intermission is expected between the two storms with the second poised to hit the region Friday evening.

Where to pick up sandbags

San Diego County officials reminded residents of unincorporated areas that they can pick up free sandbags to protect their homes from flooding.

Sandbags can help prevent runoff, mud and debris from damaging homes, clogging storm drains and flooding roadways.

"The region is still suffering through record levels of drought this year," county officials said in a statement. "Because of that, rains could trigger erosion and even debris flow, especially in areas that aren't covered by lawns, trees, shrubs and plants."

Residents can pick up sandbags that they'll have to fill themselves at several locations around the county and must bring a shovel.

County officials said sand and bags will be given away at Cal Fire stations at 17304 state Route 94 in Dulzura, 1587 state Route 78 in Julian, 16971 state Route 76 in Pauma Valley, 3410 Dye Road in Ramona and at 28205 North Lake Wohlford Road in Valley Center.

They will also be available at the Bonita-Sunnyside Fire Protection District at 4900 Bonita Road, the Boulevard Fire Department at 40080 Ribbonwood Road and North County Fire Protection District Station 4 at 4375 Pala Mesa Drive in Fallbrook. Bags but no sand can be picked up at Alpine Fire Protection District Station 17 at 1364 Tavern Road.

Bad driving conditions

San Diego County meteorologist Rand Allen told KPBS there are 120 automated weather-monitoring stations in the county that will track rainfall and electronically alert road crews. "And they'll be heading out to those areas prepared to clean up debris and mud on the road and put up cones where there's flooded areas," Allen said.

Sara Agahi, manager of Flood Control District, said roads and areas that are likely to flood in San Diego are well-known, and some are tracked by web cams.

"For example one is Quarry Road, which is over Spring Valley Creek in Spring Valley," she said. "This is a road that floods pretty much every time it rains. We have sensors on the road and as soon as there is a depth of water that would require the road to be closed there are automatic barriers that come down."