The air quality in parts of Minnesota on Saturday is at unhealthy levels, the result of the continued effects of forest fires in Canada.
The Environmental Protection Agency (EPA) identifies areas of North Dakota and west central Minnesota as having the worst air quality in the United States this morning.
The air quality is at a level that could cause adverse health effects in everyone, while members of more sensitive groups are at risk of more serious effects.
Smoke from wildfires in Saskatchewan have been moving southeast this past week, causing hazy weather across much of Minnesota. The National Weather Service has issued a weather advisory for 24 counties for Saturday morning because of the impact on air quality.
The Minnesota Pollution Control Agency's air quality index shows that cities with unhealthy air at the moment include Moorhead, Detroit Lakes and Brainerd.
Another of the areas affected is St. Cloud, with the St. Cloud Times reporting that the poor air quality could affect lung and heart health and have short term effects such as sore throats, persistent coughs, shortness of breath and burning eyes.
The newspaper says people are advised to avoid spending time near pollution sources and should reduce or reschedule their planned activities, particularly those with pre-existing lung or heart conditions, the elderly, children or those taking part in rigorous exercise.
The National Weather Service says that southerly winds will start to help the smoke from Canada dissipate during Saturday afternoon.