Atmospheric river may dump up to 4 feet of Sierra snow in what could be the last big storm of the season

An atmospheric river is predicted to dump more rain on Southern California and the Central Coast than any other storm this year, and is expected to drop up to 4 feet of snow in the Sierra Nevada and 2 inches of rain in Sacramento before dissipating over the weekend.

The National Weather Service expects a weak preliminary storm to hit Tuesday afternoon. Light rain and snow above 5,000-6,000 feet elevation is expected before a short break Wednesday morning, followed by a second system's arrival that afternoon.

Thursday should yield the harshest weather of the week, with widespread precipitation throughout California, snow down to 3,000 feet and strong gusts. Snow levels will drop even farther Friday as the storm slows into Saturday morning.

An inch to 2 inches of rain is expected in the Sacramento Valley and Bay Area this week, while forecasts for mountain passes show anywhere from 6 inches to 4 feet of snow depending on elevation.

Forecasts show the most rainfall in Southern California and on the Central Coast, where cities such as San Luis Obispo are expected to see 4 to 8 inches of rain this week. Areas ravaged by fire will be at high risk of flooding and mudslides, weather service meteorologist Eric Kurth said.

Tahoe ski resorts are reporting 8 to 12 feet of snow built up at their peaks, and the Sierra Nevada snowpack is now up to 48 percent of normal after being at just 3 percent in January. This week's storms could be the last substantial powder deposits for a while, though.

"If we do get some action behind us, it doesn't seem like it'll be that strong," Kurth said. "We're not seeing any large storms on horizon beyond this one through this week."

Benjy Egel: 916-321-1052,

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