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

That’s because this event is reminiscent of “the blob” — a massive marine heat wave that took hold in the Pacific Ocean off the West Coast of California from roughly 2014 to 2016.

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

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

From The Wall Street Journal • Apr. 6, 2026

Diaz also said it is usual to see such so much fly activity this time of year, noting that the uptick is probably connected to the recent record-setting heat wave.

From Los Angeles Times • Mar. 27, 2026

“I...just meant there’s a heat wave outside. You definitely need an iced coffee.”

From "From Twinkle, with Love" by Sandhya Menon

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