Opinion: Why Rain-On-Snow Floods From Atmospheric Rivers Could Get Much Worse

California’s latest atmospheric rivers are sending rainfall higher into the mountains and onto the state’s crucial snowpack. The rain alone is a problem for low-lying areas already dealing with destructive flooding, but the prospect of rain on the deep mountain snow has triggered widespread flood warnings.

When rain falls on snow, it creates complex flood risks that are hard to forecast. Those risks are also rising with climate change.