Stagnant air prompted a burn ban on Wednesday in four Seattle-area counties, but it's also causing more colorful sunrises and sunsets.

Share story

The same dirty air bringing the Seattle area especially vibrant sunrises and sunsets in recent days has also resulted in burn bans in four counties.

The Puget Sound Clean Air Agency issued a stage one burn ban Wednesday for King, Kitsap, Pierce and Snohomish counties. The ban prohibits outdoor fires, as well as burning in fireplaces and uncertified wood stoves. Violators could be fined $1,000.

Air trapped in the area could stick around until Saturday or longer, and may reach levels dangerous for people suffering from asthma or other respiratory conditions or heart problems, said Kimberley Cline, the agency’s spokeswoman.

The tiny particles bypass the body’s normal defenses, she said. Over time, some particles have been linked to cancer, she said.

The weather also brings with it colder nights, said Dennis D’Amico, a meteorologist with Seattle’s National Weather Service. That makes people more likely to light a fire at home, he said. The cool weather means there’s a chance of snow this weekend, the Weather Service says. More about that later.

“If you’re just lighting a fire because you like it, this is a time to not do it,” D’Amico said. “In your fireplace, the smoke is not mixing. It’s not dissipating. It’s sticking around.”

The added soot in the air means the sun is refracting off more particles in the lower atmosphere. The effect creates a prettier, more colorful show early and late in the day. That’s in addition to sunrises and sunsets that are usually more vibrant in winter, D’Amico said.

Other agencies have put burn bans in place in Thurston, Mason, Clark, Kittitas and Yakima counties.

While a windy Saturday could help lift the ban, the Puget Sound Clean Air Agency is looking at the situation daily, Cline said. She said she doesn’t expect the ban to last through the weekend.

It’s still too early to say for sure whether there will be lowland snow this weekend; meteorologists won’t have a good read on the situation until about noon Friday, D’Amico said.

Thursday night the forecast was that lowland snow may be headed our way, but exactly when, how much and how long it would last remained to be seen.

Beginning Saturday evening, “the conditions will be ripe for snow, but accumulations are difficult to pin down,” said Weather Service meteorologist Jeff Michalski.

He said the Puget Sound area is not likely to see a big dump of snow, but instead would see “isolated scattered showers, and some of those could produce snow.”

By Sunday, a 50 percent chance of snow is in the forecast. “These showers will be the hit-or-miss type,” he said. “Some place could see an inch or two and some places might not get any.”

The good news for commuters is that the snow may be polite enough to stick around only during the three-day Martin Luther King Jr. holiday weekend.

A warming trend is expected to arrive Tuesday, with snow showers giving way to rain.

It’s possible that it still might be cold enough to snow on the Tuesday afternoon commute, but that’s too far away for a detailed snow forecast, Michalski said.

Seattle Times staff reporter Jack Broom contributed to this report.

Lark Turner: 206-464-2761 or lturner@seattletimes.com.