Winter Storm Warning issued December 18 at 2:34PM PST until December 19 at 4:00PM PST by NWS

...FIRST WAVE OF SIGNIFICANT SNOW CONTINUES THROUGH SATURDAY... .THE FIRST IN A SERIES OF WINTER STORMS WILL BRING PERIODS OF HEAVY SNOW TO THE SIERRA CASCADE RANGE THROUGH SATURDAY. AFTER A BREAK IN THE RAIN AND SNOW SATURDAY NIGHT...ANOTHER WINTER STORM IS EXPECTED TO SPREAD OVER NORTHERN CALIFORNIA ON SUNDAY. THE WET PATTERN IS EXPECTED TO CONTINUE THROUGH CHRISTMAS DAY.

from Current Watches, Warnings and Advisories for the United States Issued by the National Weather Service http://ift.tt/1lXI1tK