Explaining microphysical and thermodynamic variation in BAMEX MCSs using high-resolution radar and optical array probe measurements

During the Bow Echo and Mesoscale Vortex Experiment (BAMEX), the NOAA-P3 aircraft collected in-situ microphysical data to characterize the vertical and horizontal variability of hydrometeor shapes, sizes and phases in the stratiform regions behind mesoscale convective systems (MCSs). Vertical and horizontal variations in number concentration, the slope parameter to analytic gamma fits to observed size distributions, temperature and humidity were observed among the various storms and were dependent on the aircraft's position within the trailing stratiform region. Analysis of level II WSR-88D data and airborne Doppler radar revealed that these variations occurred as the P3 sampled one of three distinct regions of evolving MCSs: the transition zone of lighter precipitation just behind the convective line, the secondary band of intensified precipitation, and the rear anvil region, in which the aircraft flew underneath the rear precipitating anvil but no precipitation reached the ground. This presentation highlights the differences in thermodynamic and microphysical structure between the three regions, and provides insight into which diabatic processes (sublimation, melting, evaporation) are important in each.