DES MOINES, Iowa -- The entire state of Iowa is under an Air Quality Alert.
The National Weather Service says north winds are bringing smoke into Iowa from wildfires in the Western U.S. and Canada.
They say heavy smoke in northwest Iowa Thursday afternoon will move south and east, reaching I-80 by midnight, then Southern Iowa by early Friday morning.
The Weather Service say smoke is expected to stay across much of the state through Friday.
Air quality will be unhealthy for sensitive groups that include the elderly, those with respiratory or heart disease and children.
They say fine particle levels will begin to improve around noon on Friday. By mid-afternoon air quality should improve below alert levels statewide.