atmospheric river

noun

plural atmospheric rivers

: a concentrated band of water vapor that flows through the atmosphere and that is a significant part of the global hydrologic cycle and an important source of regional precipitation

Environment Canada is working on a new system to rank atmospheric rivers, a type of weather system that damaged highways, flooded farms and homes, and left at least four people dead in southern B.C. earlier this week.

—Wendy Stueck

Atmospheric rivers are relatively long, narrow regions in the atmosphere—like rivers in the sky—that transport most of the water vapor outside of the tropics. These columns of vapor move with the weather, carrying an amount of water vapor roughly equivalent to the average flow of water at the mouth of the Mississippi River. When the atmospheric rivers make landfall, they often release this water vapor in the form of rain or snow.

—National Oceanic and Atmospheric Administration

In a typical year, significant atmospheric river storms occur about 10 to 15 times in California. Ultimately, they account for up to 50% of the state's precipitation.

—Paul Rogers

Examples of atmospheric river in a Sentence

Recent Examples on the Web

Atmospheric river to bring heavy rain, snow to Pacific Northwest The West Coast's latest atmospheric river is expected to begin dumping heavy rain and snow across the Pacific Northwest Friday, setting off to a multiday threat severe weather event. —Christopher Cann, USA TODAY, 21 Feb. 2025

Los Angeles was also battered by landslides this week due to an atmospheric river, which is a narrow band of moisture that carries water vapor from the tropics, often releasing it as heavy rain or snow. —Josh Hammer, Newsweek, 15 Feb. 2025

Thousands more people in Southern California were under evacuation warnings as an atmospheric river began dumping rain on the usually dry metropolis. —Joseph Wilkinson, New York Daily News, 13 Feb. 2025

And now a new atmospheric river storm is forecast to soak the Bay Area and the rest of the state Thursday and Friday. —Paul Rogers, The Mercury News, 13 Feb. 2025

Word History

First Known Use

1993, in the meaning defined above

Rhymes for atmospheric river

• caregiver
• deliver
• downriver
• lawgiver
• upriver
• giver
• liver
• livre
• quiver
• shiver
• sliver