Minnesota air quality alert: What maroon, purple, red and orange categories mean amid Canadian wildfire smoke

According to MPCA’s latest alert, the affected areas include all of Minnesota and the tribal nations of Upper Sioux, Mille Lacs, Prairie Island, Leech Lake, Red Lake, Grand Portage, and Fond du Lac.

Fine particle levels are expected to reach the following levels

Northwest Minnesota — maroon category, hazardous for everyone

North central Minnesota — purple category, very unhealthy for everyone

Central and northeast Minnesota — red category, unhealthy for everyone

Southwest and southeast Minnesota — orange category, unhealthy for sensitive groups

The alert, the first to include a maroon category in Minnesota’s history, stems from wildfires in Manitoba and Saskatchewan, with smoke carried south by a cold front. Northwest Minnesota, including Red Lake, Roseau, and East Grand Forks, faces maroon conditions (AQI 301+), deemed “hazardous” for everyone. 

Read More: Over 25,000 residents evacuated from 3 provinces over wildfire in Canada

The MPCA warned that all individuals may experience irritated eyes, coughing, chest tightness, or severe heart and lung issues, such as asthma attacks or strokes. Residents are urged to avoid outdoor activity, stay indoors, and use air purifiers, as the sky appears smoky with limited visibility, per pca.state.mn.us.

North central Minnesota, covering areas like Brainerd, is under a purple alert (AQI 201–300), labeled “very unhealthy.” This rare second-ever purple alert indicates serious risks for all, with potential for heart attacks or respiratory distress. The MPCA advises avoiding vigorous outdoor activities, rescheduling sports events, and keeping sensitive groups indoors. The air smells strongly of smoke, and haze obscures distant views, amplifying health concerns. 

Central and northeast Minnesota, including Duluth, fall under the red category (AQI 151–200), classified as “unhealthy” for everyone. Symptoms like throat irritation, shortness of breath, and worsening of heart or lung conditions are common. Sensitive groups, including children and the elderly, face heightened risks, and the MPCA recommends limiting outdoor exertion. 

Southwest and southeast Minnesota, including the Twin Cities, Rochester, and Tribal Nations like Upper Sioux, are under an orange alert (AQI 101–150), “unhealthy for sensitive groups.” Older adults, children, and those with respiratory issues may experience chest pain or wheezing. The MPCA advises these groups to reduce outdoor time and take breaks during activities.

The AQI, a 0–500 scale by the EPA, measures pollutants like PM2.5, which can enter the bloodstream via the lungs, causing severe health effects. Green (0–50) and yellow (51–100) indicate safe conditions, but orange, red, purple, and maroon signal escalating dangers, with maroon as an emergency state.