Temperatures in the Sacramento Valley are expected to warm, too, after a high of 51 degrees expected Monday and an overnight low of 44 degrees into Tuesday. Fog is likely to return to Valley spots in the mornings with temperatures ranging from the upper 50s during the day to the low 40s at night.

Tornado alley it's not, but a section of California was hit Saturday with a rare tornado that has been blamed for injuring five and flipping vehicles as a storm moved across the state.

Severe storms caused damage across northern California on Saturday, and for the first time in recorded history, the National Weather Service (NWS) issued a tornado warning for the city of San Francisco.