by John Orr
La Niña, snowpack and runoff
The picture can change quickly when you’re watching the Colorado snowpack. On March 26 snowpack as a percent of average was declining in the Arkansas basin and San Luis Valley but by the end April things had improved considerably.
The winter was dominated by La Niña. Cool water in the eastern Pacific Ocean off South America often sets up very wet conditions in the northern Rockies and a drying out across the southern Rockies. That’s pretty much what happened this year.
Up until the gangbuster snowmakers of April the eastern San Juans, Sangre de Cristos and Wet Mountains all had below average snowpack.