Since Monday we have conducted lidar observations at UMBC in support of Maryland Department of the Environment Air Quality Program. Our observations indicate the presence of particles aloft at heights between 2-6 km. Clouds were present throughout the first two days of observations. The clouds are represented in the figure by the intense red returns in our timeseries. HYSPLIT back-trajectories of the air mass between 2.5-4 km indicate that it originated in central Canada. The top right image is the HYSPLIT trajectories overlaid with last Monday's Aqua MODIS AOD retrieval indicating the presence of smoke particles over Baltimore.
NOAA HMS reported that remnant smoke originating from the wildfires in northwestern Canada is sweeping east and south into the northern central US moving east over the Great Lakes and extending to the Atlantic Seaboard and up through New England and into southern Quebec and New Brunswick. This smoke is the cause of the high AOD values reported in today's Aqua MODIS AOD retrieval. High AOD's were also reported over the Pacific Northwest, Montana and California.