A cold Arctic system that brought snow and single-digit temperatures to Oregon has been slow to retreat, leaving central Douglas County under a mass of stagnant air that’s increasing pollution.
The National Weather Service issued an air stagnation advisory and a dense fog advisory today for the Umpqua Valley.
Cold air has settled in the valley with warm air on top, which is trapping pollutants, according to Byron Peterson, natural resources specialist with the Oregon Department of Environmental Quality. The results may make breathing more difficult for those with health problems, including respiratory conditions.
Winds from a frontal system are expected to clear the air by Thursday afternoon.
Much of the bad air comes from household wood stoves, though a minority of it is produced by industry, Peterson said.
“What really affects air quality is the smoke from the wood stoves. It comes out of the chimney, and it doesn’t have a lot of velocity. It just hangs around,” he said.
Air quality in Roseburg was rated “moderate” today, rather than its usual “good.”
Cities in Oregon that currently have the worst air also have some of the lowest temperatures. Lakeview and Prineville have air rated “unhealthy,” and have had sub-zero temperatures for days.
“We ask that if people have an alternate heat source, to use it. But we understand that it’s really cold outside,” Peterson said.
Precipitation was not expected west of the Cascade Mountains until Thursday at the earliest. Freezing rain was considered possible in Roseburg and Grants Pass.
Fog was expected to limit visibility on roads to less than a quarter of a mile, according to the National Weather Service. There is also potential for icy spots.
• You can reach reporter Garrett Andrews at 541-957-4218 or by email at email@example.com.