Dangerous wildfire smoke is filling the skies from the Midwest to the Mid-Atlantic. And in some areas, conditions are expected to worsen. Through Friday, more than 115 million people are forecast to be exposed to air quality levels that are unhealthy or worse as winds funnel smoke south from out-of-control fires in Canada and Minnesota — and a heat dome traps that smoke near the ground.

As wildfire smoke from Canadian blazes continues to degrade air quality across large parts of the United States, health experts are urging people to pay close attention to one simple piece of protective equipment: their face mask.

Wildfires in Canada are pouring thick clouds of smoke into the US and will usher in unhealthy air quality for millions of people in Northeast and Midwest.

Wondering what the air quality is like outside right now? Residents can track current air quality levels across New York and around the world with this free interactive map, which uses data from thousands of monitoring stations.

Everybody is being advised to limit time outdoors as the smoke is causing unhealthy air quality.