National Weather Service Seattle office forecasters issued a special statement today forewarning of drop in air quality beginning Sunday, August 19th.
Low level smoke is likely to return to the western Washington region beginning Sunday creating the potential for air quality deteriorating to unhealthy levels Monday and Tuesday according to the special statement.
Smoke from British Columbia fires is likely to spread south into western Washington as a surface flow pattern is expected to turn offshore and northerly on Sunday. Northern areas will be affected first, including Whatcom County lowlands.
Warm weather will accompany the offshore flow bringing high temperatures on Monday and Tuesday in the 80s to low 90s.
A marine push forecast for Tuesday night or Wednesday could cool things off and also push most of the smoke out of the area.
Air quality has improved over recent days since worsening to the point of being in the “UNHEALTHY (for all)” range. But air quality has only reached the “MODERATE” range, not the “GOOD” range that is typical.