Microphysical and Kinematic Observations of Oklahoma Precipitation Events using X- and C-band Polarimetric Radar

The C- and X-band radars located around the DOE Southern Great Plains observation site provide a unique opportunity to look at microphysical and kinematic interactions across a wide variety of precipitation. The radars are ideally positioned to collect data for estimation of the 3D wind field using dual-Doppler techniques. Additionally, the colocation of two wavelengths allows for enhanced microphysical observations through the use of polarimetric radar. Herein, we describe a technique to merge the data from multiple wavelengths in order to maximize the utility of each wavelength. For example, in light precipitation and winter situations, X-band is ideally suited for detailed observations due to Kdp sensitivity. During strong convective cores such as squall lines and MCSs, C-band is a better choice owing to less attenuation and radome attenuation effects.

The resulting merged dataset is then used to derive microphysical characteristics such as hydrometeor types, radar estimated hydrometeor volumes, drop size distribution characteristics (D0, Nw), and rain rate. These are then related to the broader storm dynamics through dual-Doppler wind retrieval techniques. Two cases from the MC3E Mid-latitude Continental Convective Clouds Experiment (MC3E), 25 April 2011 and 23 May 2011, will be explored in detail. Preliminary microphysical analysis reveal populations of large drops (>5 mm) associated with the 25 April 2011 case. Additionally, a winter case from 25 February 2013 is also examined. Regions of dendrites, which may have led to enhanced surface snowfall, are identified with the X-band radar.