Photos by Paul Delaney In the span of about 24 hours between Aug. 20 (left) and Aug. 21, air quality readings across the area were the worst in the country due to wildfire smoke trapped by a stubborn high pressure ridge. Photos above are of downtown Cheney at those times and show the difference between a reading of nearly 400 and 126 on the air quality index.
On Monday, Aug. 20, a news headline appeared on social media from local television stations that was worth a double-take.
"Spokane air quality improves to unhealthy," it said.
Quite an odd accomplishment to be the best of the worst. But in the span of 24 hours, as predicted by retired Eastern Washington University geography and meteorological professor Bob Quinn, the blue skies reappeared, kinda' at least, and the Pacific Northwest is on to much better air.
And maybe an early peek at autumn?
Quinn, a noted long-range forecaster, seems pretty confident that, "We're done with our hot, hot, hot weather patterns."
He spoke of the initial signs of this change on Monday, Aug. 20, referencing a Canadian-centered high pressure system that would buffet the area with winds out of the northeast, likely breaking up the blanket of smoke, but at the same time being the cause of another red-flag warning that increases fire danger.
Almost on cue, it did the former, but luckily did not accomplish the latter.
"In the short term, that's what's going to dominate until about Wednesday (Aug. 22)," Quinn said.
As the high that has helped make the awful air drifts east, it gives way to an onshore flow of cooler, possibly more moisture-laden air.
"It will knock our temperatures down into the 70s rather than the 90s - we'll still be scratching towards 80ish you know," Quinn said. "I don't see any of these disturbances yet to bring us any rain until early next week."
What the region is looking at presently is a large but not strong warm water pool in the eastern Pacific Ocean. Normally there is a hot interior in the summer and cold water out over the Pacific.
"This tends to set us up with the strong Pacific high pressure system over that cold water pool," Quinn said. "The cold water slowly builds the marine layer up until it breaks across (the Cascade Mountains) and we get a nice marine push, and a nice little cool down for a few days."
There haven't been too many of those, but a cool trough of moisture is now dropping down out of the Gulf of Alaska. Quinn expects that to be camping off the coast for the next week to 10 days.
Quinn offered some explanation for the acrid air that has been an on-again, off-again occurrence for the past several summers.
The smoke has been trapped by the effects of the standard high pressure ridge - this one of the upper level or "aloft" variety, or upper level pattern.
"We've had not a brutally hot, but fairly normal warm summer," Quinn said. But that has been coupled with 2 1/2 months of a very dry pattern with the fuels already a bit on the dry side going into that, he added.
That's where land and fuels dried out pretty fast. A majority of the acreage wildfires have consumed so far has come in the lower elevations in places like the Columbia Basin.
And surprisingly, while the Washington State Department of Natural Resources has termed this the worst wildfire season ever, there are some important numbers to be examined.
While already there have been nearly 1,200 fire starts in Washington, they have burned but 45,000 acres as of Aug. 15 according to the National Interagency Fire Center in Boise, Idaho. And while there is still some six weeks of official fire season to go, acreage burned is less than 45,000 acres, 10 percent of 2017's total of 404,000 acres, and a fraction of 2015's torching of 1.1 million acres.
"We've lucked out," Quinn said of 2018.
Paul Delaney can be reached at [email protected].
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