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

Amaya, of NOAA, noted that the current marine heat wave almost certainly would have formed in the absence of climate change.

From Los Angeles Times • Apr. 16, 2026

By mid-March, alarming snow deficits all over the Western states were capped off by a record-breaking heat wave that melted much of the remaining snowpack.

From Slate • Apr. 11, 2026

The good news is that the upcoming rain will push back the start of this year’s high fire season, alleviating some concerns following the recent record-breaking heat wave.

From Los Angeles Times • Apr. 10, 2026

There was a heat wave that week, so I was constantly sweating.

From The Wall Street Journal • Apr. 6, 2026

“Darling, there’s a heat wave and I’m not going to be talked out of a salad.”

From "Atonement" by Ian McEwan

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