Spokane's fires destroyed more than 700 structures. The smoke is now the story for five states

Three wildfires that started around Spokane on Saturday 1 August have become the most destructive fire event in Washington state's recorded history, and the smoke they are producing is now affecting five states and three Canadian provinces.

The fires — Old Trails, Autumn Lane and Fairview, together called the Spokane Complex — had burned more than 10,000 acres by early this week. More than 700 structures have been destroyed, around 640 of them in the Old Trails Fire alone. For scale, the 1991 firestorm that Spokane still measures these events against destroyed 114.

Roughly 67,000 people have been ordered out. Level 3 "Go Now" evacuation zones remain in place, though some zones were downgraded on 4 August as conditions eased. Containment as of 5 August stood at 13 per cent on both the Old Trails and Autumn Lane fires and 5 per cent on Fairview. Crews have shifted from cutting line to strengthening what they have, working mop-up and putting out pockets of heat near buildings still standing.

No deaths and no injuries have been reported. Fourteen people were listed as unaccounted for by the Spokane County Sheriff during the first days; all fourteen were confirmed safe. That is a genuinely better outcome than the early reporting anticipated, and it is worth stating plainly, because in a fire that moved through neighbourhoods this fast the assumption ran the other way.

The conditions that drove it were extreme and specific. Spokane International Airport recorded sustained winds of 33 miles per hour gusting to 44 on Saturday afternoon, with temperatures at 86 degrees and relative humidity between 20 and 25 per cent, as a dry cold front passed through. Those numbers describe a fire that spreads faster than people can be moved.

A 37-year-old man, Aaron Farinacci, has been arrested and charged with arson in the first degree in connection with the Old Trails Fire. A charge is an allegation. It has not been tested in court, no plea or verdict has been reported, and nothing here should be read as a finding that he started the fire.

For most of the region, though, the immediate question is not the fire line. It is the air. Smoke has reached Portland, Seattle, Boise, Salt Lake City, Vancouver and Victoria. The National Weather Service has said fine particulate matter — PM2.5, the fraction small enough to reach deep into the lungs — may reach unhealthy levels through the weekend, particularly downwind of the active fires. An air quality alert has been in effect for Spokane County since 2 August, with conditions forecast to run from unhealthy toward hazardous.

That is the practical takeaway. Air quality during a smoke event changes by the hour and by the neighbourhood, and no article can tell you what it is where you are standing. The two places that can are airnow.gov, the EPA's monitoring network, and spokanecleanair.org, the Spokane Regional Clean Air Agency's hourly readings. Health guidance during a smoke episode comes from the Spokane Regional Health District rather than from fire updates.

Acreage, containment and structure counts are all still moving. Every figure here is given with the date it was reported, and this page will be updated as the agencies revise them.