heat wave

American  

[heet weyv] / ˈhit ˌweɪv /

Or heatwave

noun

Meteorology, Climatology.

1. a period of abnormally hot and usually humid weather; heat event.

   I moved to the coast up north because summer back home has become one long, unbearable heat wave.

2. an air mass of high temperature covering an extended area and moving relatively slowly.

   Another heat wave is expected to form across the South and into the Northeast by week’s end.

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heat wave British  

noun

1. a continuous spell of abnormally hot weather

2. (not in technical use) an extensive slow-moving air mass at a relatively high temperature

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Etymology

Origin of heat wave

First recorded in 1875–80

Example Sentences

A record-breaking heat wave is scalding California, with major consequences for the state’s most important reservoir: its snowpack.

From Los Angeles Times • Mar. 21, 2026

This weather event is currently on track to be the hottest March heat wave on record, said weather service meteorologist Rose Schoenfeld.

From Los Angeles Times • Mar. 18, 2026

“This is a pretty unprecedented heat wave because of the duration of it,” Steward said.

From Los Angeles Times • Mar. 18, 2026

Temperatures started soaring Thursday and Friday, and though they dipped over the weekend, the heat wave dialed back up on Monday.

From Los Angeles Times • Mar. 18, 2026

The heat wave was supposed to last at least five days.

From "The Lemonade War" by Jacqueline Davies

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