https://www.mercurynews.com/2019/02/12/in-sierra-nevada-atmospheric-river-storm-creates-chaotic-forecast/

A potent ‘atmospheric river’ approaching California on Tuesday morning is creating a “chaotic forecast” for meteorologists with the National Weather Service in Reno who are working to determine impacts from the storm, including snow levels.

Zach Tolby, a meteorologist with the weather service, said the forecast has been difficult because weather scientists are dealing with two storms merging into one.