Stagnant weather patterns in recent days have caused high air pollution levels in the southwest corner of Pennsylvania and nearly all of the eastern half of the state, prompting health concerns and the issuance of air quality alerts that more commonly occur in the summer.
The state Department of Environmental Protection has declared Air Quality Action Day alerts due to high concentrations of airborne particles over a broad swath of the eastern half of Pennsylvania this week, and predicted lesser but still elevated air pollution levels for Pittsburgh and the southwestern corner of the state.
Eric Shirk, a DEP spokesman, said the high pollution readings have been caused by a stationary front that has controlled the state’s weather for most of the week.
“The winter tends to have much more wind, which prevents the stagnation of the often damp air,” he said. “When there is less or no wind, as has been the case in the past several days, it allows the moisture and particulate matter to build to a level that warrants an Air Quality Action Day.”