Massive wildfires sparked across western Ontario and the Boundary Waters Canoe Area in Minnesota continue to burn and grow. Heavy smoke has been filling the skies over the last couple of days, with smoke spreading through the Great Lakes into the Northeast and Mid-Atlantic states on Wednesday, July 15. The smoke is occurring on the edge of the heat dome across the northern U.S. that has been causing extreme hazards due to heat. Now, the increasing smoke and particulate matter may lead to other health risks for vulnerable groups over the next several days.

Upper-level winds are out of the northwest, pushing this smoke southeast across the Great Lakes and into portions of the Mid-Atlantic and Northeast. These winds will largely be in place through the end of July. A quick response by first responders and firefighters could help limit the duration, but multiple days of smoky skies are in the forecast.

Air quality alerts have been raised from Minnesota to Boston and will likely spread south through Chicago to Washington, D.C., over the coming days. Current images and webcams on social media from northeast Minnesota to the Mackinac Bridge in Michigan show how thick this smoke can be when it stays near the surface.

See more images on social media:

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Besides making for some smoky skies and beautiful sunsets, wildfire smoke is dangerous for vulnerable groups like asthmatics and the elderly. Those sensitive to wildfire smoke should continue to watch the air quality forecast from the U.S. EPA here: www.airnow.gov.

Some changes in the weather could help break up the consistency of the smoke and make conditions less hazardous. A weather system will move through these areas on Friday and Saturday, July 17-18. In addition to bringing rainfall that could help fight the fires, rainfall can also help clear the air and disperse the smoke some. Another system moving through on Monday could do something similar. Between systems, changing winds, however slightly, may also break up the thick smoke plumes, dispersing them to some degree and offering some relief.

However, if these fires are not put out quickly, we could see this becoming a long-duration event beyond this weekend for those around the Great Lakes and possibly into the Northeast and Mid-Atlantic as the prevailing upper-level wind pattern remains out of the northwest through the end of July.

Read more at, "How Wildfire Smoke May Affect Corn During Silking and Fill Stages," https://www.dtnpf.com/…

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John Baranick can be reached at john.baranick@dtn.com

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