The Minnesota Pollution Control Agency has canceled an air pollution advisory for western Minnesota issued Thursday – but it issued an alert for the eastern two-thirds of the state through Friday night.
The air in that area is considered unhealthy for sensitive groups that include the elderly, children, people with heart and breathing ailments and people working strenuous outdoor jobs, the Associated Press notes.
What's to blame? Temperature inversions, snow melt and fog are among the factors trapping fine particle pollution near the ground, health officials say. The air quality is expected to improve as a cold front pushes slowly eastward through the state Friday night.
The Twin Cities on Friday had a fine-particle count of 95, close to the 100 threshold in which the pollution agency says the air is unhealthy for sensitive groups. The agency issued the map below Friday.
What the ratings mean:
Good: Current air quality is considered satisfactory and poses little or no health risk.
Moderate: Air quality is acceptable; however individuals who are very sensitive to air pollution may experience adverse health effects.
Unhealthy for sensitive groups: People with lung or heart disease, older adults, children, and people participating in activities that require heavy or extended exertion may experience adverse health effects.
Unhealthy: Everyone may begin to experience adverse health effects and members of sensitve groups may experience more serious health effects.