Brace yourselves, smoke is on its way

North winds and then east winds by mid- week. Smells of smoke. Even in western Washington.

Statewide air quality is mostly Good at present, except for the Methow valley and Darrington. Previous forecast for the Methow is expected to remain valid for the next few days.

Smoke from the Suiattle fire has caused air in Darrington to degrade to Unhealthy for Sensitive Groups. Some relief is expected during the daytime hours today but smoke will likely remain trapped in the valleys overnight and worsen when the morning inversion breaks. Air quality is expected to vary between Moderate and Unhealthy over the next few days, depending on fire activity.

The big story is that the north winds are transporting smoke from British Columbia wildfires into northern Washington. Satellites show that large plumes have already crossed the northern border and will likely impact communities in Okanogan and Whatcom counties between now and Wednesday. Expect air quality to vary between Good and Unhealthy for Sensitive Groups. Some models (see forward trajectories at different heights) suggest this smoke could push all the way down to King County by late Tuesday. We will be watching this closely.

Forecast models show smoke draining further into central WA by mid- week, so communities along the Okanogan river valley should brace for Moderate or poorer air.

Please take a look at the "Smoke and Health" section of this blog, which provides several resources to protect yourself from the harmful effects of smoke.

On the bright side, smoke plumes that remain aloft will offer a little relief from the oppressive heat by providing a thin sun shield that lowers temperatures a degree or two. And they will cause pretty sunsets.

Winds turn easterly from Wednesday onward and while this might reduce the BC smoke faucet, it will likely transport smoke from western Montana to eastern Washington. More on this in the next update.