First Of Week's 2 Rain Systems Enters California

SACRAMENTO (CBS13/AP) -- The first of two rainy weather systems predicted this week is moving through California.

The system isn't considered a big rainmaker but its instability brings a slight chance of thunderstorms.

Some rain is expected in the valley, while snow is already falling at the 2300' level in the Sierra.

Sierra school districts are canceling classes for the day due to the snow.

Light rain is expected through midmorning Monday in the San Francisco Bay Area and in Monterey Bay around noon.

Santa Barbara County has issued a pre-evacuation advisory for residents living near wildfire burn scars like the one that disgorged devastating debris flows last month.

The storm is expected to reach Santa Barbara County in the afternoon and persist overnight into Tuesday.

A stronger and wetter system is expected later in the week.

Santa Barbara County's pre-evacuation advisory is the lowest level of a new three-tier warning system.