[Leftcoast]

Most California reservoirs have dual purposes - Water Storage and Flood Control.  Reservoirs with a flood control objective will drop their water level swiftly prior to the next rainy season so they can capture any unexpected early run-off.  

A flood control manager's nightmare is a steady, drenching atmospheric river hitting the Sierra's before they've created needed capacity in the reservoirs.  (Or alternatively, an early, heavy snowfall followed by a pineapple express/warm rainfall).  I'm also hearing that they are planning for a higher snow line now due to warming trends which means that more of the water from those rivers goes straight to run-off and isn't stored as snow.

You'll see most reservoirs dropping water in the next two months. Given the last two years experience and newer warming models they are likely to start earlier than in the past.

[Leftcoast]

Most California reservoirs have dual purposes - Water Storage and Flood Control.  Reservoirs with a flood control objective will drop their water level swiftly prior to the next rainy season so they can capture any unexpected early run-off.  

A flood control manager's nightmare is a steady, drenching atmospheric river hitting the Sierra's before they've created needed capacity in the reservoirs.  (Or alternatively, an early, heavy snowfall followed by a pineapple express/warm rainfall).  I'm also hearing that they are planning for a higher snow line now due to warming trends which means that more of the water from those rivers goes straight to run-off and isn't stored as snow.

You'll see most reservoirs dropping water in the next two months. Given the last two years experience and newer warming models they are likely to start earlier than in the past.