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Atmospheric River Bringing Heavy Rain to Southern California and Heavy Snow to the Sierra Nevadas

A strong atmospheric river will continue heavy rain over southern California through Friday. The heaviest rainfall is ongoing today in the Los Angeles Basin. Flash and urban flooding is possible. A prolonged heavy snowfall has begun over the Sierra Nevada Mountains and will continue through Friday. Travel will become increasingly difficult over the passes due to snow and strong winds. Read More >

1200 UTC NAM 250 mb Heights, Isotachs, and Wind (kts)

Forecasts are based on the daily 1200 UTC NAM run and are updated daily by 1400 UTC.  Additional models runs can be found here