Wildfire smoke descends across central US, causes 'unhealthy' air quality

The sun looked orange as it shined through a thick blanket of wildfire smoke on Tuesday across a large area of North America, including in Denver, and the smoke could spread even farther in the coming days.

The sun appeared orange and red through a layer of haze on Tuesday morning as a large blanket of wildfire smoke covered part of the central United States and Canada.

Air quality reached unhealthy levels in parts of North Dakota, eastern Montana, eastern Wyoming and northeastern Colorado where the thickest smoke was concentrated. Dense smoke also obscured the sky over the Canadian Prairies.

The air quality in Denver quickly declined on Tuesday morning. It started the day at "poor" levels and reached "unhealthy" levels before midday, making conditions hazardous for anyone who spends time outdoors.

While the core of the smoke shrouded the North Central states, its true extent was visible from space. On Tuesday morning, satellite images revealed that the smoke had spread as far south as Texas and as far east as Michigan and Ohio.

Air quality in these areas was elevated but not to the extent of the unhealthy conditions reported in the northern Plains.

Where is the wildfire smoke coming from?

Large wildfires burning across the western United States and Canada have been spewing massive plumes of smoke into the atmosphere in recent days. Winds have been guiding the smoke over a large swath of North America, including areas hundreds of miles away from some of the blazes.

Where is the smoke heading?

AccuWeather forecasters say the smoke will continue to expand across the northern United States and most of Canada in the coming days. The thickest smoke is expected from eastern Oregon and eastern Washington into Minnesota and across the Canadian provinces of Alberta, Saskatchewan and Manitoba.

Some layers of smoke higher in the atmosphere could also extend into the Midwest, Northeast, Ontario and Quebec.