Boise’s air quality has improved since the weekend. So why is the sky still so hazy?
The Boise area saw air quality in the “unhealthy” category this past weekend as wildfire smoke from around the Northwest converged on the Treasure Valley. By Tuesday, the air quality had improved significantly — reaching the “good” category in Boise at points — but the sky remained a hazy brownish-orange.
Michael Toole, local airshed coordinator for the Idaho Department of Environmental Quality, said that despite appearances, air in the Boise area is improving and smoke will continue to clear out over the next few days.
“What we’re seeing now is (smoke) clearing at ground level, but we are still seeing … what we call aloft (smoke),” Toole said in a phone interview. “It’s coming over our area, but it’s higher in the air.”
Bill Wojcik, a meteorologist with the National Weather Service’s Boise office, told the Statesman that most of the current smoke plume is coming from fires in California. A cold front is expected to sweep more of the smog from the Treasure Valley, potentially offering peeks at blue sky.
Toole said the current conditions are a break for Boise residents’ lungs.
“It’s not very aesthetically pleasing — it just looks hazy and gray — but a lot of that smoke is not coming down to ground level,” Toole said.
On Tuesday morning, Toole lifted burn restrictions put in place for most of Southwest Idaho at the end of last week.
“Air quality over the weekend was just nasty,” he said. “Every fire in the region, it all just met over Idaho.”
Monitoring stations in the Boise area recorded fine particulate matter, also known as PM 2.5, at around 160 on the air quality index for most of the weekend. At that concentration, fine particles inflame the lungs and can cause potential health problems for vulnerable individuals, like children and the elderly.
By Tuesday afternoon, the air quality index in Boise was around 70.
Toole said air quality at times will fluctuate into the orange or red categories in the next few days, but should stay there only briefly as plumes of smoke move over the valley.
This story was originally published August 17, 2021 at 1:36 PM.
