The Michigan Department of Environmental Quality has declared Thursday an ozone action day in Washtenaw and several other southeast Michigan counties.

The alerts are issued when ground-level ozone and fine particle pollution exceed levels considered healthy.

People and businesses are urged to avoid activities that lead to ozone formation. These activities include: refueling vehicles, using gasoline powered lawn equipment and using charcoal lighter fluid.

This Ozone Action Day comes earlier in the year than normal. Since 2000 no Ozone Action Days have been declared before June.

National Weather Service meteorologist Steve Considine said the alerts are usually issued when temperatures are warm and humid is high. The weather service predicts a high of 84 Thursday and humidity levels ranging from about 90 percent in the morning to about 40 percent in the afternoon.

Besides Washtenaw, other counties included in the Ozone Action Day are Lenawee, Livingston, Macomb, Monroe, Oakland, St. Clair and Wayne.

For further information, see the Michigan Department of Environmental Quality air quality index page.