Rain moved in the Valley just before 8 p.m. Thursday night, and the scattered showers are expected linger into the mid-morning hours on Friday.
People with weekend plans in Yosemite may have to find another way to get there as a result of the storm.
The park service has closed Tioga Road, Glacier Point Road, and Mariposa Grove Road.
Up to seven inches of snow is expected to fall on parts of the roads by the time the storm wraps up.
The park service says conditions will be re-assessed later Friday morning and the closed roads could reopen as soon as midday.
Chains are recommended if you're planning to visit Yosemite on Friday.