Some parts of Washington state, like Walla Walla County, could see dozens more 95-degree-plus days if only modest action is taken on climate change, according to an analysis of climate models.

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As an apocalyptic haze blanketed Seattle last week, temperatures soared into the 90s and left Seattleites ruing their lack of air conditioning.

Welcome to the future?

Scientists project climate change will exacerbate wildfire activity. Extremely hot days — 95 degrees and above — are expected to become more common.

How hot will it get? A consortium of researchers with the Climate Impact Lab has analyzed two consensus climate models and projected changes nationwide. The lab shared data for each of Washington’s counties with The Seattle Times.

[App users, view interactive map of Washington state counties and predicted changes in temperature here.]

Historically, King County has averaged less than one day (.37) a year at or above 95 degrees.

But by 2080-2099, this value will likely increase to between 2.5 and 8 days, assuming countries take action on climate change roughly equivalent to agreements in the Paris climate deal. If emissions are at a higher pace that assumes population growth and only modest action on climate change, King County residents will likely see between 6 and 26 of these extremely hot days, and have a 1-in-20 chance of having 39 days of 95 degrees and above.

“The Northwest does pretty well as far as staying reasonable under a lot of these scenarios,” said Michael Delgado, an analyst at the Rhodium Group, a research partner involved in the Climate Impact Lab. But in some areas of the state, he said, whole months of the year are sliding into extremely hot temperature ranges.  

Under the high-emissions scenario, Walla Walla County could expect to see between 56 and 86 extremely hot days by 2080-2099. Historically, it averages just under 18.

Yakima County, Washington’s cornucopia of produce, would likely see between 47 and 80 extremely hot days during that period. Its historical average is 11.