A powerful winter storm brewing near the Pacific Northwest known as a bomb cyclone is dragging an atmospheric river.

Bomb cyclone is a term used by weather enthusiasts to describe a process that meteorologists usually call bombogenesis. It’s the rapid intensification of a cyclone in a short period of time, and it can happen during powerful storms such as the one northern California and the Pacific Northwest are preparing for this week.

A major storm was sweeping across the northwest U.S., battering the region with strong winds and rain and causing widespread power outages and downed trees that killed at least one person