The summer of poor air quality in North Dakota may be coming to an end.
The air quality first deteriorated in early July, but it improved by late August and has largely stayed better with the exception of a hazy day last Friday. The outlook hinges in part on the weather over the Northern Rockies in the Western United States, and it's possible North Dakotans could still see a few days more of haze this month.
"I imagine it's going to take the first few snowfalls out there in the higher terrains where these fires are raging to really knock these fires down," said Zack Hargrove, a meteorologist with the National Weather Service in Bismarck.
Some of those areas already have seen winter storm alerts.
Nevertheless, fires are still burning out West. Whether their smoke reaches North Dakota depends on weather patterns and the wind, said Jim Semerad, director of the Division of Air Quality with the state Department of Environmental Quality.
"We have had some other years when we have been affected by wildfire smoke but to our recollection we have never seen anything to this extent," said Semerad, who has monitored air quality within the state since 1984.
The smoke has caused particulate matter levels to spike in parts of the state this summer. The tiny particles can exacerbate respiratory issues when they get into people's lungs. It's also possible that the hot summer could have caused more ozone to form over the state, something state environmental officials are evaluating and will compare to previous years in a report at the end of the year, Semerad said.
Some of the worst air quality seemed to come in August, but it varied greatly across the state and by the hour, he said. Sometimes smaller fires closer to North Dakota sent a lot of smoke this way. Other times, the skies turned hazy because of bigger fires farther away.
Semerad said he believes North Dakota's 10 air quality monitors cover the state well, though at times air quality maps offered the impression that there's a gap in coverage north of Jamestown to the Canadian border. The state's monitors feed data to the U.S. Environmental Protection Agency, whose computers form maps showing air quality conditions in real time across the country.
Environmental Quality isn't necessarily going to move any of its monitors, but that's something on Semerad's mind. Most monitors exist in the western part of the state near industrial sources, as well as at Theodore Roosevelt National Park. Adding a new monitor could cost $100,000 and must be approved by the EPA.
"We don't want it to be construed that we're looking the other way from the Bakken or the coal plants," he said of the possibility of moving an existing monitor. "It's a judgment call."
Semerad said it's too soon to predict whether next summer's air quality will be better or worse than this year's. Forest management practices and climate change both play a role in wildfires, he said.
The entire Western United States as far east as the Rockies, along with the Upper Great Plains, is in some form of drought, according to the U.S. Drought Monitor. Many parts of those regions have seen particularly hot temperatures this summer.
That's been the case in North Dakota, but it appears the sweltering heat might be over for the state's residents. The National Weather Service predicts highs mostly in the 70s this week.
"In a general sense, we are definitely on the way to fall," Hargrove said.
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