Snowpack is a crucial component of California’s water supply.  While heavy winter or spring rains can bring replenishment to streams, rivers, and reservoirs snowpack levels also have a significant impact on water storage and supply.  In spring months, long after rains have ceased, warm weather melts snowpack, replenishing reservoirs and rivers.

April 1 is typically the peak of snowpack levels for the water year. As is typical, temperatures begin to heat up as we move through spring and summer approaches, converting snowpack to increased reservoir storage. Visit our reservoir page for updated reservoir levels.

Snowpack measurements typically begin for the water year in January.

The atmospheric river that has occupied much of California for the last week has increased the statewide snowpack by more than 40 percent.