A major winter storm, fueled by a renewed atmospheric river, will bring heavy rain and mountain snow to both Northern and Southern California on Wednesday and Thursday. … By Wednesday evening and into Thursday morning, showers and thunderstorms will linger locally, while the pulse of heavy precipitation will shift southward, bringing several inches of rain and mountain snow to Central and Southern California. … Across the Sierra, snowfall levels will start out above 6,000 feet when snow begins Wednesday morning. As precipitation intensifies Wednesday evening, much colder air will sweep in, dropping snow levels to around 2,500 to 3,000 feet.

Other weather and snowpack news across the West:

• Los Angeles Times: Atmospheric river threatens heavy rain, snow, flooding in California
• USDA Natural Resources Conservation Service: News release: Snowpack conditions reflect typical La Niña patterns
• The Salt Lake Tribune (Utah): Colorado River forecast: Experts predict weak spring runoff, despite February storms
• The Daily Sentinel (Grand Junction, Colo.): State snowpack still underperforming with typical peak levels a month away
• The Gazette (Denver, Colo.): Snowpack lags across southern Colorado, strong for Denver and Colorado Springs​
• This Is Reno (Nev.): Nevada’s snowpack at 94% of median, down from last year’s level
• YubaNet (Nevada City, Calif.): NID March snow survey: snowpack at 96 percent
• The Plumas Sun (Quincy, Calif.): Lassen Volcanic National Park measures snowpack
• Tracy Press (Calif.): Snowpack improves with February storms