* WHAT. The Minnesota Pollution Control Agency has issued an Air Quality Alert for fine particles pollution. The Air Quality Index (AQI) is expected to reach the Orange or Unhealthy for Sensitive Groups category. * WHERE. Northwestern Minnesota. * WHEN. From 5 PM CDT Wednesday until 11 AM CDT Thursday. * IMPACTS. Sensitive groups, such as people with lung disease (including asthma), heart disease, and children and older adults, may experience health effects. * ADDITIONAL DETAILS. Smoke from numerous wildfires across the Saskatchewan province in Canada will travel south into northwestern Minnesota from the early evening on Wednesday through Thursday morning. Air quality is expected to reach the Orange (Unhealthy for Sensitive Groups) AQI category across the alert area during this time. Air quality should improve by Thursday afternoon, as cleaner air moves in on northerly winds.