4:30 p.m. update: Rain continues to fall across portions of the Sacramento Valley. The National Weather Service says to watch for ponding of water on roads and minor flooding in poor drainage areas.
2:30 p.m. update: Thunderstorms dropped pea-sized hail across Sacramento this afternoon. The National Weather Service reports that weak funnel clouds have been spotted and will be possible into the afternoon.
Original story:
Snow is making driving difficult in the northern Sierra Nevada and rain is falling in the Central Valley as the first of two storms predicted for this week moves through California.
The National Weather Service's Sacramento office says Interstate 80 and U.S. 50 are mess Monday, with estimated delays over Donner Summit running around 50 minutes.
Forecasters simply advise avoiding travel there if possible.
The system is expected to arrive in Southern California late in the day and overnight into Tuesday.
In southern Santa Barbara County, hit hard by debris flows last month, a pre-evacuation advisory has been issued for residents living near wildfire burn scars. The weather service says the chance of thunderstorms is slight but the system does have instability.