A pair of atmospheric rivers will spread rounds of rain and snow over the next several days. A pair of potent storm systems known as atmospheric rivers are spreading rounds of rain and snow across the Pacific Northwest and Northern California over the next several days.

The storms pushing off the Pacific are the result of an atmospheric river, a corridor of air heavy with moisture that forms when warmer air from the tropics moves toward the poles. As the first of the two storms pushes inland on Monday,