The Minnesota Pollution Control Agency has upgraded the severity and geographic range of the air pollution health advisory issued Thursday. The agency has now placed the eastern two-thirds of Minnesota under an air pollution health alert. In this portion of the state, air quality conditions are considered unhealthy for sensitive groups.
Strong temperature inversions, snow melt, and morning fog are trapping fine particle pollution near the surface across much of the state Friday.
Air quality conditions are expected to improve as a slow-moving frontal system passes over Minnesota. Conditions will first improve in the west and are expected to improve in the easternmost parts of the state by this evening. Since 5 a.m. Friday, air monitors in western Minnesota indicate that cleaner air has moved into the region.
The MPCA issues an air pollution health alert when air quality conditions reach levels that are unhealthy for sensitive groups, or an Air Quality Index greater than 101. An air pollution health advisory is issued when air quality conditions are expected to approach levels that are unhealthy for sensitive groups, but the Air Quality Index is not expected to reach 101.....