If you smelled the air on Mother's Day weekend and thought, “Where’s the fire?,” you weren’t alone. Wildfires in Canada and northern Minnesota combined with weather conditions to push a “perfect storm” of smoke across much of Minnesota.
The resulting haze dimmed an otherwise sunny weekend and brought with it the acrid odor of a campfire — a really big one, stretching across a whole region — as well as watering eyes, scratchy throats, and an air quality health advisory issued by the MPCA.
The situation began cooking on Friday, May 6 around noon, when MPCA air quality staff picked up in satellite photos a smoke plume streaming southward from Canada. The smoke was not from the huge fire that devastated the city of Fort McMurray in Alberta, but rather a new one in Woodland Caribou Provincial Park in southern Ontario. MPCA meteorologist Steve Irwin, who is also a pilot, noticed the plume pointed straight at International Falls; he called the local airport there, who confirmed visibility was rapidly deteriorating to 1-2 miles and their air was getting thick and smoky.
Steve Irwin (left) and Daniel Dix (right)
As part of the MPCA unit that makes the call on when to issue air quality alerts, Irwin and MPCA colleague Daniel Dix, both degreed meteorologists and self-professed “weather geeks,” quickly consulted their networks, crunched data on the plume’s potential path, and issued an Air Pollution Health Advisory for northeastern Minnesota for that afternoon into Saturday. The MPCA issues advisories and alerts during heavy haze conditions because of health impacts from fine particles in the air, and as Irwin and Dix monitored their screens at home (“Weather geeks do this,” said Daniel) they saw particle counts in Ely jump sharply upward around 7 p.m.
“It was obvious with the heavy smoke in International Falls and the northwest winds that the Arrowhead region was going to be impacted by the smoke,” Dix said, “and what we saw from the Ely monitoring station verified this. Concern for the Arrowhead and North Shore region was definitely warranted with these high monitored values.”
Around this time the MPCA’s statewide monitoring network went down due to a system glitch, vexing thousands of people trying to get more detail from the MPCA’s Air Quality Index (AQI) website. But at least the advisory had been issued in time to inform Arrowhead commuters and travelers heading north for the weekend, and the meteorologists went to bed having warned vulnerable populations and expecting things to improve on the morrow.
But at 5:30 on Saturday morning, rising early for a family trip, Irwin casually grabbed his phone from the bedside to check conditions (like we said, weather geeks) and noticed smoke had now enveloped the Twin Cities metro and southeastern Minnesota. “Uh oh,” he thought, and quickly phoned Dix and others in their unit to have the team issue an alert for the Twin Cities and southern Minnesota. The monitoring network was coming back online showing very high numbers, and by this time the National Weather Service also was fielding calls from the public about the smoke, so Dix contacted them about the situation as well. Not only had an unexpected weather change shifted the smoke abruptly southward, but two new fires in northern Minnesota were adding to the smoke.
The particle index on Saturday, May 7, reached the “purple” zone with a reading of 240, the highest AQI ever recorded in Minnesota.
Irwin had to leave for his trip and turned the reins over to Dix, who quickly issued an Air Pollution Health Alert for a larger portion of the state, and with a higher hazard level than Friday’s advisory. Ultimately, the particle index on Saturday rose to 240, beyond the “red” zone of conditions that are potentially harmful for even healthy people, into the purple zone. This was uncharted territory for Minnesota; it’s the highest AQI recorded since we began tracking in the early 1990s.
By Saturday evening, the smoke had largely cleared out from most of Minnesota and headed into Iowa and Missouri, where it fouled their skies well into Mother’s Day.
With northern wildfires on the increase in recent years, and a warmer than average summer expected, Dix said we may see more smoke events this summer.
You can keep abreast of smoke and haze conditions on the MPCA’s Air Quality Index page, where you can also sign up to receive air quality alerts.