Image: Atmospheric River on Monday, February 20, 2017 PST

University of Wisconsin SSEC via Category 6

An atmospheric river of moisture extended from Hawaii to the San Francisco Bay area in California at 3 am PST Monday, February 20, 2017, as seen in this satellite-derived measurement of total precipitable water (TPW)--the total amount of water that would fall on the ground if one were to condense out all of the water vapor in the atmosphere.