U.S. Air Quality

Haze over Baltimore

Hazy skies prevailed during our observations, due to the polluted air mass that is trapped between the advancing cold front in the north and the Tropical Storm Fay in the south, as Meloe and Amy indicated for the last posts. Nighttime observations were carried out Maryland's Department of the Environment l(MDE)ow level jet studies. No conclusive signs of LLJ activity were observed last night. The boundary layer extended up to 2.5 km, with occasional clouds advecting over the lidar (red counts above 2 km). Code Orange PM2.5 AQI levels were recorded at MDE's Oldtown monitoring station during the time when greatest amount of scattering was observed by ELF within the boundary layer.