As of 1 November, the 12 "key reservoirs" in California held only 23% of their combined capacity. The average content as of that date is 56% of capacity.
At this time of year, the reservoirs are normally low, waiting for the spring and summer snow-melt to refill them. However, they currently hold less than half the amount of water that they would normally hold.
Precipitation in the first month of the current rain-year -- which started 1 October -- was below average at 16 weather stations. Two stations were above average. Yosemite had 3.21 inches in October, 60% above average; this should help the water supply for San Francisco. Death Valley had 1.08 inches in October, more than 15 times the average for the month.