AQ Story: Unhealthy Air Expected to Affect the Eastern U.S., June 8-9, 2011

Poor air quality is forecast for much of the Midwest, New England, and the mid-Atlantic states on Wednesday, Thursday, and possibly into Friday as temperatures reach the mid-90s to low 100s, and an upper-level ridge of high pressure dominates the eastern United States.

Mostly sunny skies will enhance the formation of ground-level ozone, and light winds caused by a surface high pressure system centered over the mid-Atlantic region will allow pollutants to build up at ground level. Furthermore, smoke from wildfires near the Arizona / New Mexico border and from Mexico will be transported into the central and eastern U.S. Small particles from smoke have a direct effect on particle pollution levels; in addition, gases in smoke can react with sunlight to form ground-level ozone pollution.

Air quality on Thursday is expected to be Unhealthy for Sensitive Groups (Code Orange or over 100 on the Air Quality Index) in more than 80 cities including Baton Rouge, La., Indianapolis, Detroit, Nashville, Tenn., Columbus, Ohio, Philadelphia, Pittsburgh, Newark, N.J., Richmond, Va., and Atlanta. As a result, many local air quality agencies throughout the region have called air quality action days. For a complete list of action days, please visit

The below graphic shows Wednesday’s AQI forecasts overlaid on Tuesday’s visible satellite imagery.

Health Tip: Cut back on strenuous outdoor exercise when air quality is expected to be unhealthy. When ozone is elevated, this is especially important for children, older adults, and other sensitive groups, such as people with asthma or other respiratory diseases. Children, older adults, people with lung disease and people with heart disease also are susceptible to the particles in smoke and should pay close attention to air quality levels.

How You Can Help: Choose a cleaner commute—share a ride to work or use public transportation. Bicycle or walk when possible. Combine errands and reduce trips. Avoid idling your engine.