Thick, choking plumes of smoke from wildfires in Canada are pouring into major cities across the Midwest, Northeast and mid-Atlantic, bringing dangerous air quality to more than 100 million people. The polluted air will last through at least Saturday in some areas as new waves of smoke waft south.

Here’s the latest:

• Millions affected: More than 100 million people in 18 states and the District of Columbia are under air quality alerts. “Very unhealthy” and “hazardous” air quality stretches from northeast Minnesota to southeast Virginia.

• Widening reach: Smoke is being carried south Friday, and Washington, DC, is now experiencing dangerous air quality. But the smoke is still on the move: weather patterns will determine which cities have the worst air quality each day.

• MLB game postponed: The Cleveland Guardians game against the Pittsburgh Pirates was postponed Friday due to poor air quality in the Cleveland area. The game will be made up Saturday in a split doubleheader. Sporting events like the RowFest National Championships In Michigan were also called off Friday.