3 Sierra passes to close Thursday ahead of winter storm

California highway officials say they will close three mountain passes near the Nevada line between Lake Tahoe and Yosemite National Park on Thursday as a precaution ahead of an early winter storm that’s expected to bring rain and snow to the Sierra.

Temperatures were plunging Wednesday in Reno and the Sierra’s eastern front ahead of the cold front. Highs were forecast to drop 10 to 15 degrees Fahrenheit (below normal Thursday through Saturday with weekend lows near and below freezing, the National Weather Service said.

"Confidence is increasing in the chances for rain and high elevation snow showers Thursday into Friday," the service said. Several inches of snow are possible at the higher elevations.

An even older air mass is expected to move into the region Monday and Tuesday, when snow levels could drop to the valley floors.

Caltrans officials said the road closures on routes off of U.S. Highway 395 will begin at noon Thursday on State Route 108 at Sonora Pass north of Bridgeport, California. State Route 89 at Monitor Pass south of Lake Tahoe will close at 2 p.m. and State Route 120 near Lee Vining, California at 5 p.m.

Highways could reopen on Saturday after Caltrans crews evaluate conditions.