Most of southern Minnesota south of a line from Ortonville to St. Cloud and Cambridge has been placed in an air quality alert until 9 p.m. Friday because of unhealthy particles brought to the Midwest by wind carrying smoke from Canadian wildfires.
The explanation from the Minnesota Pollution Control Agency is complicated, but it all leads to a simple result: the air quality is unhealthy for sensitive groups, including people with lung disease, asthma, heart disease, children and older adults.