atmospheric river

American  

[at-muhs-fer-ik riv-er, -feer-] / ˌæt məsˈfɛr ɪk ˈrɪv ər, -ˈfɪər- /

noun

Meteorology.

1. a long, narrow corridor in the atmosphere that transports massive amounts of concentrated water vapor from the tropics: often responsible for extratropical cyclones and other extreme weather events, but also for commonly weaker systems of rain that replenish water supplies. AR

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Etymology

Origin of atmospheric river

First recorded in 1990–95

Example Sentences

By late April, temperatures had begun to rise, but reports indicated that unsettled, wet conditions were still on the way for Southcentral and Southeast Alaska as an atmospheric river approached.

From Science Daily • May 6, 2026

California’s snowpack remains below average despite the powerful atmospheric river storms that pounded the West Coast around Christmas, state officials announced Tuesday.

From Los Angeles Times • Dec. 30, 2025

Heavy rain from an atmospheric river system caused flooding and mudslides, particularly in areas still scarred by wildfires.

From Salon • Dec. 27, 2025

The atmospheric river storm soaking Southern California is expected to peak Saturday, with officials warning of potential flooding and damaging landslides.

From Los Angeles Times • Dec. 23, 2025

The rains would be fueled by atmospheric river storms, which pounded the Pacific Northwest earlier this month, causing flooding and evacuations.

From Los Angeles Times • Dec. 16, 2025