Smoke from Canadian wildfires is causing air quality concerns for millions of Americans in the Midwest and Northeast.

An Air Quality Alert is in effect until 11 PM on Sunday for parts of Maine and New Hampshire due to expected high levels of particle pollution.Air quality is expected to reach levels that are considered “Unhealthy for Sensitive Groups” due to a plume of smoke moving in from Canada.

After a hazy end to the weekend, wildfire smoke will continue to pass through Maine in moderate to high amounts today. Particle pollution will be unhealthy for sensitive groups. Highs will vary in the 70s and 80s with a good amount of sunshine.