Brilliant sunlight punching through thick morning fogbanks and illuminating blue afternoon skies seemed to be a good sign for this Thanksgiving weekend.

But while the weather has been gorgeous to the eye, it is also a danger to human lungs. This week, a number of state and regional air pollution authorities declared much of Western Washington to be under an “air stagnation watch.”

A high-pressure weather system sitting over Puget Sound has trapped pollutants from cars, wood stoves, industry and open burning to degrade air quality in most counties surrounding Whidbey Island. Jamie Randles, director of the Northwest Air Pollution Authority, said his agency sent out an advisory asking Island, Skagit and Whatcom county residents to refrain from outdoor burning and the unnecessary use of fireplaces and wood-burning stoves. The advisory also asks that drivers spend as little time as possible on the road.

With Kitsap, Snohomish, Skagit and King counties under official burn bans and pollutants at a level at which the National Weather Service has recommended against vigorous outdoor activity, Randles said the area is in an unusual situation.

“It doesn’t look very good,” he said. “This is really a bad time for everybody.”

Randles said the high-pressure cell over Western Washington is trapping pollutants near ground level. With almost no wind in the forecast through the weekend and no predicted break in the weather, he said there is nothing to clear it away.

NWAPA is keeping an eye on pollutant levels through several air quality monitoring devices in the counties it monitors. The level of pollutants, which is measured in micrograms per cubic liter of air, was rising this week to a point at which NWAPA could call a burn ban. That point is 60 micrograms per liter of pollution particles 10 microns in size. On Wednesday, a Bellingham monitoring station recorded a pollution level of 25.8.

Randles said NWAPA has no pollution measurements for Island County, since there are no monitoring stations on either Whidbey or Camano islands. But since every county around the islands is experiencing poor air quality, the NWAPA advisory applies here as well.

Randles said this is the first time this year NWAPA has sent out an air quality advisory. If air quality continues to degrade, the state’s Department of Ecology could issue a warning for the western half of the state.

Randles said air quality should improve quickly once the weather breaks and when winter breezes begin blowing.