Mount Shasta, California – Interstate 5 south of Weed could turn snow-covered by early Monday as heavy mountain snow spreads into Siskiyou County, creating dangerous travel conditions through 4 a.m. Wednesday.
According to the National Weather Service in Medford, a Winter Storm Warning is in effect from 10 a.m. Sunday until 4 a.m. Wednesday for elevations above 3,000 feet across western, southern and eastern Siskiyou County.
Above 5,000 feet, 8 to 12 inches of snow will fall through Monday morning, followed by an additional 6 to 12 inches Monday night through Tuesday. The highest terrain could see 1 to 2 feet total. Winds will gust up to 40 mph across exposed ridges, reducing visibility and drifting snow over passes.
Highways 97 and 89, Interstate 5 south of Weed, Black Butte Summit, Snowman Summit, Dead Horse Summit and Grass Lake Summit are all at risk for chain controls or temporary closures. Etna Summit on Sawyers Bar Road and Highway 3 south of Callahan will also become hazardous.
Snow levels begin near 5,000 feet Sunday, lowering to around 4,000 feet Monday and dropping to near 2,000 feet by Tuesday morning. That shift could bring 1 to 3 inches of accumulation into Scott and Klamath River valleys and possibly Mount Shasta City during heavier bursts.
Drivers should delay non-essential travel, carry emergency supplies and check Caltrans updates at 511 or QuickMap. Conditions may briefly ease Monday afternoon before intensifying again Monday night, with warnings remaining in effect through early Wednesday.
