Analysis of PECAN 2015 MCSs Utilizing Airborne- and Ground-Based Doppler Observations and Airborne In Situ Microphysical Data

During the summer of 2015, numerous mesoscale convective systems (MCSs) were observed as a part of the Plains Elevated Convection at Night (PECAN) experiment. Ground-based observations were gathered by a suite of mobile Doppler radars, mesonets, and sounding arrays. Additionally, the NOAA P-3 aircraft performed pseudo-dual-Doppler legs and spiral ascents/descents within the transition zone and enhanced stratiform rain region of many of these MCSs. Several of these spirals were conducted behind developing bow echoes, with at least one spiral within a rear inflow jet. The NOAA P-3 was outfitted with the X-band (3.2 cm wavelength) NOAA Tail Doppler Radar (TDR), providing for high resolution remote sensing of reflectivity and radial Doppler velocity. Additionally, Optical Array Probes (OAPs) were mounted on the NOAA P-3 and their data used to compute particle number, sizes, and shapes.

A subset of the TDR data collected during missions containing microphysical spiral ascents/descents has been synthesized with data from several ground-based radars using the Spline Analysis at Mesoscale Utilizing Radar and Airborne Instrumentation (SAMURAI) technique. These SAMURAI analyses provide a detailed estimate of the kinematic and radar reflectivity structure during several periods of system evolution. Data collected by the OAPs during these spirals were processed by the University of Illinois OAP Processing Software, allowing for the generation of vertical profiles of particle mass and number distributions, total water content, total number concentration, and median mass diameter. When considered in the context of the SAMURAI analyses, these profiles and accompanying profiles of in-situ aircraft relative humidity and temperature help explain how the microphysical cooling processes occurring in various regions behind the MCS leading convective line influenced the system dynamics. The relationship between diabatic cooling and the flows within this nocturnal elevated MCS will be discussed.