A high pressure ridge over the Northwest is likely to leave a blanket of stagnant air over Washington until next week, leading to more burn bans and possible problems for people who already have trouble breathing, officials said.
The National Weather Service expected to issue an air stagnation advisory Tuesday for Western Washington to go along with one already in effect east of the Cascades, said meteorologist Jay Albrecht.
"It's a pretty strong ridge aloft" with warm air trapping colder air close to the ground in the inversion pattern typically responsible for smog building up on cold, dry winter days.
"The sun is not really strong enough this time of year to break the inversion," Albrecht said Tuesday. "Down in the valleys here it can get pretty murky."
Until the pattern changes, vehicle exhaust and wood smoke hang around in the air. Some of the seven regional clean air agencies in Washington have already issued burn bans covering King, Pierce, Snohomish, Thurston, Clark and Yakima counties.
Pollution in some place has reached unhealthy levels at times for sensitive groups - people with breathing issues or illness, the elderly and young children, said Kimberley Kline, spokeswoman for the Puget Sound Clean Air Agency.
The agency issued a Stage 2 burn ban Sunday in the counties that include Seattle, Tacoma and Everett. However, the agency said due to improving conditions, they will downgrade the ban to a Stage 1 at 1 p.m. Tuesday, which allows burning in wood stoves certified by the Environmental Protection Agency. Violators could face a fine of up to $1,000.
Agency inspectors drive around looking for smoke coming out of chimneys, Kline said. People who want to complain about their neighbors' smoke can report them on the agency's website.
Inspectors photograph the smoke and review it before mailing a violation notice to the home. They aren't looking for confrontations or trying to make money for the agency, Kline said.
"We're looking to start a conversation and begin an education," she said.
The agency had more than 100 violation reports in an earlier ban over New Year's, she said. This inversion could last longer.
"Air quality the next few days is going to be a concern so those who are sensitive should take precautions," Kline said. "Those who like to have fires, please refrain until the pollution clears and we can all breathe easier again."