Ebbetts Pass on Highway 4, Sonora Pass on Highway 108 and Monitor Pass on Highway 89 will be closed until noon on Thursday, Caltrans District 10 announced on social media Friday, prior to the storms. The closures come as the Sierra is hit with its first big snowfall of the season, the result of a storm system that started making its way over Northern California on Monday.
“We’ve had snowshowers move over the Sierra starting Monday, and that’s really accumulating Tuesday from the early morning into this evening,” said Dakari Anderson, a meteorologist with the National Weather Service’s Sacramento office.
Showers are expected to continue into Tuesday evening until they begin tapering off Wednesday morning, Anderson added.
Ebbetts Pass is closed from Lake Alpine to Raymond Meadows, according to Caltrans. Sonora Pass is closed from Kennedy Meadows to the Marine Corps Mountain Warfare Training Center near Leavitt Meadows, and the entirety of Monitor Pass is closed from Highway 4 south of Markleeville to Highway 395 near Topaz Lake.
Official snowfall reports aren’t yet available, Anderson said, and the nature of this storm is complicating snow accumulation measurements due to its mixture of both snow and rain.
The National Weather Service’s forecast for the western slope of the Sierra Nevada states that rain showers will continue at lower elevations until Wednesday morning, then will likely start again Wednesday night. One to seven inches of snow are expected to accumulate at higher elevations, with snow levels starting at 6,500 feet on Tuesday then lowering to an elevation of 5,500 feet on Wednesday at midnight. Snow levels are expected to rise to 6,000 feet by Wednesday morning, officials said.
Caltrans recommends checking its online QuickMap for road conditions, chain requirements and closures.