(NEXSTAR) – It’s not uncommon for the U.S. to be impacted by wildfire smoke during the summer, even if those fires are in a different state or country. But, barely a month into summer, multiple states have been blanketed in apocalyptic-like smoke that caused hazy skies and poor air quality – sometimes for days at a time. 

Unfortunately, these waves of smoke likely aren’t going away any time soon. 

The smoke is coming from Canada, with fires in Quebec and Ontario causing much of the air quality impacts in the U.S. As of Wednesday, more than 30,000 square miles of the country have burned – a record, according to the Canadian government. That’s roughly the size of South Carolina. 

There are 485 active fires, 243 of which are out of control.

Again, it’s not uncommon for Canadian wildfire smoke to creep into the U.S. but it typically happens in the middle of summer, and often doesn’t cause multiple days of unhealthy air quality alerts across numerous states. 

“We usually see wildfire smoke from Canada a couple of times a summer,” WSYR’s Dave Longley explains. “In those instances, the fires are in central and western Canada, and the smoke is at high altitudes and doesn’t affect air quality down here on the ground.”

Longley, who has over 30 years of experience in meteorology, notes that the proximity of some of the fires burning this year also makes it easier for the smoke to impact the U.S. Persistent northerly winds have also helped to carry smoke from Canada’s fires. 

So how long will the Canadian wildfire smoke be in the U.S.?

There are multiple factors that can impact that. As Longley mentioned, northerly winds have helped to carry smoke down into the Midwest and Northeast. Many parts of Canada are also experiencing drought conditions, producing dry fuel for the fires. Rain could help to not only mitigate the drought, but temper the fires. 

Otherwise, you can largely expect the fires to keep burning. Many of the wildfires are burning in remote areas of the country, Longley explains. Because wildfires are a natural part of the life of forests, and they currently have limited impact on infrastructure, they’ll be left to burn. 

This also means the smoky skies that have frequented dozens of U.S. cities so far this year will persist through the summer, Wisconsin Department of Natural Resources Cooperative Fire Specialist tells Nexstar’s WFRV.

Some fires, like the 3,400 square mile Donnie Creek fire in British Columbia, could burn into the winter, The Canadian Press reports.

In addition to smoke from our neighbors to the north, it’s also common for smoke from fires in the western U.S. to impact states on the opposite side of the Mississippi. While the record snowfall and relentless rain states like California experienced over the winter and into spring helped to diminish concerning drought rates, it didn’t necessarily mitigate the risk for wildfires. 

The precipitation did help to replenish vegetation in California that was struggling in extreme drought conditions over the last few years. That now-lush vegetation can now become fuel for a fire, should one break out, Dr. Chris Potter, an ecologist with the Earth Sciences Division at NASA’s Ames Research Center told Nexstar’s KWSB.

“When you build up your vegetation to those levels, the fire risk goes up. Just logically, there’s more to burn,” Dr. Potter explained. “That’s sort of the downside for our wet years.”

Ultimately, it’s difficult to tell how often and for how long into the year the U.S. will be impacted by Canadian wildfire smoke, but it’s likely to stick around for a while.