Answer:
The Minnesota Pollution Control Agency (MPCA) has upgraded the north Twin Cities metro, south Twin Cities Metro, and Saint Cloud areas to the red air quality index (AQI) for Tuesday afternoon and Wednesday afternoon. The red AQI category is unhealthy for everyone.
An air quality alert for central and southern Minn. remains in effect from noon on Tuesday, June 20, through 9 p.m. on Thursday, June 22. The affected area includes central and southern Minn., and the tribal nations of Leech Lake, Mille Lacs, Upper Sioux, and Prairie Island. In the orange AQI area, sensitive groups should limit prolonged outdoor exertion.
Ground-level ozone is expected to be high during the afternoon hours on Tuesday, Wednesday, and Thursday across central and southern Minn. Ozone will be highest during the afternoon and early evening hours when sunshine is most abundant, and temperatures are highest. Ozone will be low in the morning, late evening, and overnight.
Ground level ozone has increased rapidly as of midday Tuesday, and ozone is now expected to reach red AQI in the north Twin Cities metro, the south Twin Cities metro, and St Cloud area. The last time ozone reached the red AQI in Minnesota was June 27, 2012. In the red area, everyone should limit prolonged outdoor exertion