The Pennsylvania Department of Environmental Protection (DEP) has declared a Code Red Air Quality Action Day for all of Pennsylvania due to smoke from Canadian wildfires. The drifting smoke has caused concerns about air quality throughout the Great Lakes region and parts of the central and eastern United States. Erie, Pennsylvania, is experiencing the worst air quality in the state, with levels at 196 as of Wednesday morning. Pittsburgh and Indiana County are also reporting unhealthy air quality levels. The DEP warns that conditions could worsen throughout the day, particularly in western Pennsylvania. The smoke is expected to impact air quality in Pennsylvania through Saturday, with some possible relief on Sunday. An atmospheric inversion is keeping the smoke-filled air closer to the surface and is preventing mixing with air from higher elevations. In West Virginia, the smoke has cast a haze and poor air quality across northern, western, and central parts of the state. Detroit, Pittsburgh, and Indianapolis are also reporting very unhealthy or worse air quality due to the fires.