MINNEAPOLIS – Wildfires burning in western Canada continue to impact the U.S., as another round of smoke blows south and affects air quality.
This week, the smoke made its way back into the northern tier of the U.S., prompting air quality alerts in North Dakota, Minnesota and Montana on Wednesday and Thursday.
The air quality is worst in central North Dakota, where levels are very unhealthy in and around cities such as Bismarck.
WIND DRIVES CHEMICAL LEAK FROM OHIO EXPLOSIVES PLANT INTO NEARBY COMMUNITIES

(FOX Weather)
Unhealthy air quality levels stretch into Montana and South Dakota, while parts of northwestern Minnesota can expect unhealthy levels for sensitive groups.
Levels in Minnesota continue to be a problem on Thursday, with orange levels expected throughout most of the state.
The Minnesota Pollution Control Agency issued an Air Quality Alert for central and southern Minnesota until 11 p.m. CST Thursday.
By Friday, things should clear up.
Smoke could drift eastward this week, impacting the northeast and mid-Atlantic as well.
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Smoky sunrise on June 11 from Blackburg, Virginia.
(@NWSBlackburg/X / FOX Weather)
A photo from Blackburg, Virginia, showed a hazy sunrise at the National Weather Service office on Wednesday morning.