flash flood

American  

noun

1. a sudden and destructive rush of water down a narrow gully or over a sloping surface, caused by heavy rainfall.

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flash flood British  

noun

1. a sudden short-lived torrent, usually caused by a heavy storm, esp in desert regions

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flash flood Scientific  

/ flăsh /

1. A sudden, localized flood of great volume and short duration, typically caused by unusually heavy rain in a semiarid area. Flash floods can reach their peak volume in a matter of a few minutes and often carry large loads of mud and rock fragments.

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Synonym Usage

See flood.

Etymology

Origin of flash flood

First recorded in 1935–40

Example Sentences

On Sunday morning local time, officials began to stand down some evacuation and flash flood warnings on Oahu, but other parts of the state remained under threat.

From BBC • Mar. 22, 2026

Authorities warn that the same storm system is now threatening other islands, with flash flood alerts and evacuation warnings issued for parts of Maui, Molokai and Lanai.

From Salon • Mar. 22, 2026

The platform highlights locations where there could be flash flood risks on a map.

From The Wall Street Journal • Mar. 12, 2026

The weather service also issued a flash flood warning for southwest Los Angeles County for Thursday.

From Los Angeles Times • Dec. 25, 2025

Instead of feeling distraught over this turn of events, moreover, McCandless was exhilarated: He saw the flash flood as an opportunity to shed unnecessary baggage.

From "Into the Wild" by Jon Krakauer

Related Words

• deluge
• torrent