Wired: California’s huge storm could cause disastrous melting in the mountains

Flooding and snowmelt are more likely when intense weather systems come in quick succession. “It is clear we will have both of these issues this weekend, with a very warm atmospheric river following on the heels of a very cold atmospheric river,” says Daniel Swain, a fellow at UCLA’s Institute of the Environment and Sustainability. “We have a lot of substantial snowpack in the Sierras right now, and a lot of that at lower elevations might be washed away as rain. I would be surprised if there wasn’t a big contribution to snowmelt.”