Health and meteorological officials warned on Thursday that smoke from wildfires in Canada is moving towards the central United States and could persist in the coming days.

Since early Friday morning, air quality alerts have been issued in several states, including Nebraska, Washington, Montana, and Wisconsin. A special meteorological statement on air quality was also issued in Wyoming.

Denser concentrations of smoke are expected to shift eastward, reaching the Midwest later in the day, impacting major metropolitan areas such as Chicago, Indianapolis, and St. Louis.

Canada has experienced an exceptionally active start to the wildfire season. Last week, devastating wildfires in Alberta burned more than 150 times the area compared to the combined total of the past five years for the same period.

In Nebraska, the National Weather Service in Omaha tweeted on Thursday: "Smoke from Canadian wildfires will move through the area from today until tomorrow morning, resulting in potentially hazardous air quality and reduced visibility in eastern Nebraska and Iowa. It is recommended to limit outdoor activities when air quality is poor!"

The Omaha office of the weather service reported on Thursday afternoon that the smoke from wildfires is "beginning to affect the metropolitan areas of Lincoln and Omaha." Visibility is expected to drop to 1-2 miles within the next two hours, and air quality will be in an unhealthy range for sensitive groups.

In Douglas County, eastern Nebraska, which includes Omaha, the health department warned that the smoke could persist until Saturday.

The air quality index from the U.S. Environmental Protection Agency indicated that parts of the Rocky Mountains, Great Plains, and Midwest, including the Nebraska Panhandle and the northeast corner of the state, had "very unhealthy" air quality early on Friday.