PORTLAND, Ore. (KOIN) -- For the first time ever, Portland and all of the Willamette Valley have been placed under an "Extreme Heat Warning" by the Portland National Weather Service.

This is the first time the National Weather Service (NWS) is using its new terminology when warning the public about dangerous temperatures. Early this summer, the NWS issued an "Extreme Heat Watch" for the first time. However, temperatures rapidly cooled compared to forecast highs, prompting the watch to expire prematurely.

This week's heat was upgraded to the warning status after an initial watch was issued.

The NWS started using this new classification for dangerous heat in March of 2025. The new terms are “Extreme Heat Watch” and “Extreme Heat Warning.” The "Heat Advisory" remains the same.

Extreme Hea

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