What counts as a heat wave? It's a life-or-death question.

[marmar]

(Grist) You know a heat wave when you feel it — oppressively hot weather that makes you desperate for an ice-cold drink, or better yet, air conditioning.

But nailing down what counts as a heat wave is surprisingly tricky. Temperatures vary widely from place to place — normal summertime weather in Las Vegas would be considered scorching in Seattle. Then there’s the matter of climate change. How do you even say what “normal” temperatures are when heat records are getting obliterated, sometimes over a weekend?

This isn’t a matter of semantics. It’s a matter of life and death. Excessive heat, according to the National Weather Service, is the number one weather-related killer in the United States. Defining a heat wave helps cities know when and how to respond to deadly temperatures — issuing heat advisories, sharing tips for surviving the heat, and opening up cooling centers.

Recent heat waves across the West have helped fueled wildfires now raging in Oregon, Washington, and California much earlier in the summer than usual. The Southwest blistered in its third heat wave of the summer last weekend, driving temperatures to new record highs. Death Valley had what’s thought to be the hottest 24-hour-period on the planet, averaging 118.1 degrees on Sunday. .............(more)

https://grist.org/extreme-weather/what-is-a-heat-wave-climate-change/

[Towlie]

1. Simple: It means more than a community is prepared to deal with, just like the cold wave in Texas.

 
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But I doubt that the definition of a phrase is a life-or-death question.