Meteorological and air quality measurements were conducted as part of the “Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality (DISCOVER-AQ)” campaign during the summer of 2011 in Edgewood, MD. In situ ozone mixing ratios from the NASA P3B aircraft profiles, free-flying and tethered ozonesonde profiles and the Nittany Atmospheric Trailer and Integrated Validation Experiment (NATIVE) surface monitoring station are compared. The agreement between the measurements is dependent on synoptic- and meso-scale meteorological phenomena such as the occurrence of the bay breeze and the stability of the planetary boundary layer. Results from case studies illustrate these effects on the comparisons in more detail.