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The entire state of Minnesota was under an air quality alert May 18 due to wildfire smoke originating in Canada.
The alert, issued by the Minnesota Pollution Control Agency and the Minnesota Department of Health, was in effect through the morning of May 19.
“Fine particle levels are expected to reach the red air quality index category, a level considered unhealthy for everyone,” the alert stated.
“In the red area, everyone should avoid prolonged time outdoors.”
Rock County was in the “red” zone where the air was hazy and had a distinctive smell of smoke.
The compromised air quality was due to a band of heavy ground smoke from wildfires in northern Alberta and Saskatchewan, according to the MPCA release.
“The smoke should clear rapidly overnight,” the MPCA said Thursday.
A full description of air quality categories is available at airnow.gov.
On Monday afternoon, the MPCA and state Department of Health issued an air quality alert due to ozone.
“Southerly winds are transporting pollutants into the state,” the statement read.
“Sunny skies, warm temperatures and low humidity will allow these pollutants to react to the air to produce ground-level ozone. … This is considered unhealthy for sensitive groups.”
The ozone alert was made for the southern half the state and lasted through Tuesday.
During ozone alerts residents should:
•reduce vehicle trips and fill up the gas tank at dawn or dusk.
•carpool when possible.
•postpone use of gas-powered lawn and garden equipment.
•avoid backyard fires.