Two people were found dead in Northern California floodwaters amid an atmospheric river that dumped a record amount of rain.

An atmospheric river dumped record rainfall and feet of snow in Northern California. Flooding and feet of snow in Northern California as atmospheric river rolls through

A bomb cyclone occurs when a storm's pressure drops quickly, which intensifies the storm and ramps up wind gusts. Atmospheric rivers are a "long, narrow region in the atmosphere—like rivers in the sky—that transport most of the water vapor outside of the tropics," according to the National Oceanic and Atmospheric Administration.