Rain and snow are expected to fall across Southern California through today before conditions dry up over the weekend.

In the Inland Empire and Orange County, precipitation moved in on Wednesday, with the heaviest amount expected today.

In mountains above 1,500 feet elevation, snow will fall — with even Santiago Peak potentially getting a few inches — while more was expected on Mount San Jacinto, said Adam Roser, a National Weather Service meteorologist. Idyllwild could see about 10 inches of snow.

Lake Arrowhead could get 6-12 inches of snow through Friday, with Big Bear Lake catching as much as a foot to 18 inches, meteorologists said. Expect road closures and requirements for snow chains, with travelers advised to pack extra food, clothes and water in case they get stuck.

Lower on the mountain, plan on 2-4 inches in areas between 4,000 and 5,000 feet elevation.

Coastal Orange County could receive half an inch of rain, with inland areas possibly getting a bit more. Temecula, Murrieta and Hemet might see an inch of rain.

Highs will be in the 50s today in Orange and Riverside counties.

Mountain passes and foothills will be visited by gusts of wind of 50-60 mph and 30-40 mph, respectively.

In Los Angeles County, the Mountain High area could get 10-12 inches of snow, with most other mountain stretches catching 3-6 inches.

“It’s going to be slippery and icy,” said meteorologist Mike Wofford of the National Weather Service. “Best to wait for another day if you’re going to go up there.”

If anyone has to go through the Grapevine on the 5 Freeway during the precipitation, Wofford said he or she should prepare for long delays.

On most of L.A. County’s flatlands, showers could bring a quarter of an inch to half an inch of rain in some areas — and no rain in other parts. Temperatures are expected to be in the high 50s and low 60s today, with highs in the 60s and 70s over the weekend.

Precipitation should clear up by Friday, with warmer temperatures and sunny skies moving in.