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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Related Words

See flood.

Etymology

Origin of flash flood

First recorded in 1935–40

Example Sentences

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

Honolulu Department of Emergency Management has issued multiple flash flood warnings and urged residents to move to higher ground and avoid flooded areas.

From BBC • Mar. 21, 2026

Google said the Southern African Development Community used the tool to pick up an imminent flash flood in Mozambique.

From The Wall Street Journal • Mar. 12, 2026

"In my entire life, there had never been a flash flood this high here. But the rain kept pouring," said Merliana.

From Barron's • Dec. 3, 2025

Twenty years before Hrdlicka’s mockery, a flash flood tore a deep gully into a ranch in the northeast corner of New Mexico, near the hamlet of Folsom.

From "1491" by Charles C. Mann

Related Words

• deluge
• torrent