Wildfire smoke and bad air quality threatens sports: Yankees, Blue Jays, World Cup Final, Phillies-Mets and more games to watch closely

A smoky haze has descended upon a number of cities in the northern part of the United States and into Canada.Wildfires raging in Minnesota and across the Canadian border have led to unsafe air quality ratings in a number of cities, including Toronto, New York, Buffalo and Boston.There are no guarantees about how things will progress in the days ahead, but it's going to be a storyline worth watching as MLB comes out of the All-Star Break, and as the World Cup heads toward its final on Sunday in New Jersey.Why is the air quality bad?Wildfires are raging in the Duluth area of Minnesota as well as into Canada, which happened similarly last summer.The smoke from the fires is then blown on the east-bound wind into many of the cities in the Northeast of the United States, as well as the Ontario p