The second storm, forecasters say, could bring thunder and dump up to 2 inches of rain in central and southern valleys, 2 to 4 inches in the foothills and up to 6 inches in some mountain spots.
State water officials plan Thursday to survey the anemic mountain snow pack, and will likely find that California's precipitation is badly lagging what's needed to quench the region's thirst. 2013 was California's driest year on record.
In Nevada, the first of back-to-back storms dropped several inches of snow at Lake Tahoe and up to a foot and one-half on the mountain ridges.
A winter weather advisory was put into effect from 4 p.m. Wednesday to 10 a.m. Thursday for the Reno-Tahoe area, south to Mammoth Lakes.
The second wave of wetter weather begins Friday night into Saturday.
A frigid air-mass from Canada is now over Northern California bringing snow to the Sierra and freezing temperatures to the Sacramento Valley. Meteorologists say this is not typical winter weather for the region.
Thursday afternoon at 1:02 p.m., the West Coast officially transitioned from summer to fall during the autumnal equinox.
Multiple records were again broken Thursday as temperatures in the region soared well above 100 degrees as they have for the past week. Where's the Delta Breeze?
This heat wave has prompted a flood of phone calls for air conditioning repairs and some customers may be on a long waiting list.
A wealth of weather and climate data and the jobs of the scientists who analyze it may be at risk under President Trump’s budget proposal.