Winds have caused smoke from a wildfire in the northeastern woods of Minnesota, near the Canadian border, to drift Tuesday afternoon all the way to Chicago.

According to the National Weather Service, the smoke moved into Northern Illinois this afternoon from a fire that’s been raging in Minnesota’s Boundary Waters area for several weeks – more than 400 miles away. The weather service said winds from the north and a new cold front are what’s causing the smoke to creep into Illinois.

“The combination of sinking air and northerly winds behind the front has transported smoke all the way to Illinois,” a statement from the National Weather Service said. “The smoke will likely persist through the afternoon and into the morning hours before the winds become more westerly.”

Locals should expect hazy skies and a distinct burning odor, and people with respiratory problems should try to stay indoors. The National Weather Service noted that in Lake County, along the Wisconsin border, the smoke was strong enough to cause burning eyes and make breathing difficult.

The Chicago Tribune reported earlier today that the wildfire occurred in the Boundary Waters Canoe Area Wilderness. The fire was reportedly started by lightning on Aug. 18 near the town of Ely.