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

That so-called Pineapple Express was forecast to be the strongest atmospheric river storm to hit Southern California in nearly two years, according to the National Weather Service.

From Los Angeles Times • Feb. 13, 2026

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

From Salon • Dec. 27, 2025

The so-called Pineapple Express was forecast to be the strongest atmospheric river storm to hit Southern California in nearly two years, National Weather Service meteorologist Rose Schoenfeld said.

From Los Angeles Times • Dec. 24, 2025

Water levels receded until February 2024, when an atmospheric river dumped an additional 1.5 inches of rain onto the lake, making it deep enough that people could kayak on it.

From Los Angeles Times • Dec. 12, 2025

Residents in the Pacific Northwest of the US and Canada are bracing for what could be record setting floods as an atmospheric river dumps heavy rain on already swollen rivers.

From BBC • Dec. 11, 2025