NWS: NorCal Reservoirs in Good Shape Thanks to Great 2016/17 and Average 2017/18 Precipitation WeatherBrains | June 6, 2018 | Weather Share this article Credit: NWS While Sierra snowpack was below average this spring, NorCal reservoirs are sitting fairly full heading into the summer. This is due to a wet 2016-2017 winter and near average Sierra precipitation this past winter. You might also like: Posted by WeatherBrains | June 6, 2018