After enduring days of record-setting, eye-watering levels of smoke in the air, the Seattle area is in for relief, thanks to a shift in wind patterns. But the debate over whether this is the “new normal,” the old normal or the abnormal is likely to play out for months and years to come.
The National Weather Service is predicting a rise in onshore air flow, sweeping plumes of wildfire smoke toward the east (sorry about that, Wenatchee) and moderating temperatures. Thursday’s high temperatures in the Seattle-Olympia area are expected to be 12 to 17 degrees Fahrenheit cooler than today’s.
Much of the smoke should be cleared out by Friday, and there’s even a chance of showers over the weekend.
In his latest blog post, University of Washington atmospheric scientist Cliff Mass explains the mechanism behind this week’s smoky skies: An express train of lower-atmosphere winds delivered smoke from fires in the North Cascades and southern British Columbia directly into Puget Sound.
Air quality is expected to improve tonight through Thursday as onshore flow returns, pushing in cleaner marine air! #WAwx pic.twitter.com/glhRQnJvWA
— NWS Seattle (@NWSSeattle) August 22, 2018
Particulates in the air sparked air quality alerts that kept many folks indoors, when they weren’t snapping apocalyptic-looking photos of the dim landscape.
Mass said those particulates appeared to have a cooling effect, reducing the amount of sunlight reaching the surface so that what might have been high temperatures in the mid- to upper 90s ended up staying in the 80s.
The blanket of smoke also held in heat during the night, leading to overnight low temperatures that were about 10 degrees above what they might have otherwise been, Mass said.
Is this a taste of the new normal in an era of global warming? Not necessarily. Mass has argued persuasively that the wildfire trend actually marks a return to the “old normal” after nearly a century of aggressive fire suppression and forest mismanagement.
Last week, federal officials and lawmakers announced that they’d redouble efforts to reduce hazardous fire fuels, through such measures as prescribed burning and mechanical tree removal. Will that be enough, or is there more that needs to be done? Let’s just hope the measures to be taken over the next year will reduce wildfires and head off another smoky summer.