The definition: An atmospheric river (AR) is a long plume of moisture that stretches from the tropics or subtropics into ...

Days after an atmospheric river brought record-setting rainfall to California, the state is in the crosshairs of another rainy storm system.

An atmospheric ... the West Coast of North America ahead of a strong Pacific cold front at least once or twice each fall, winter or spring. But ARs also happen over the Atlantic and South Pacific ...