Polarimetric and Atmospheric Profiling Measurements of Convective Snowbands and Atmospheric Waves during PLOWS

During the winters of 2009 - 2011, the UAHuntsville Severe Weather and Radar Group conducted field operations on winter cyclones and convective snowbands as part of the multi-institution Profiling of Winter Storms (PLOWS) field project. Two unique convective snow events were sampled by a collection of radars and profiling instrumentation during intensive observation periods (IOPs) on 04 December 2009 near Davenport / Clinton IA and 10 January 2011 over northern Alabama. This study utilizes integrated observations from these IOPs during PLOWS to delineate and analyze mesoscale gravity waves, Kelvin-Helmhotz waves, and regions of convective snow in winter cyclones. The high resolution measurements were obtained primarily from integrated instrumentation of the Mobile Integrated Profiling System (MIPS), which includes a LIDAR ceilometer, 12-channel microwave profiling radiometer (MPR), 915 MHz Doppler wind profiler, vertically pointing X-band radar (XPR), and standard surface meteorological measurements. Data from the Mobile Alabama X-band (MAX) and ARMOR C-band dual polarization radars, various National Weather Service WSR-88D S-band radars, and the North Alabama Lightning Mapping Array (NALMA) were also utilized in this analysis. Additional profiling measurements and soundings were obtained from the NCAR Mobile Integrated Sounding System (MISS), as well as the University of Missouri and UAHuntsville mobile sounding systems.

This analysis will focus primarily on the impact of atmospheric wave kinematics on winter precipitation substructures and possible enhancement of depositional growth, riming, and aggregation by utilizing multi-Doppler syntheses, polarimetric radar, vertically pointing radar, and MPR measurements. Preliminary analyses indicate fine-scale enhancements in specific differential phase may be used to identify and differentiate atmospheric waves in stratiform snow regions from distinct snow bands. An examination of polarimetric ice and snow signatures during PLOWS and their relationship to convective snowband electrification will be presented. Additionally, analyses of integrated profiling measurements of stability and subsequent impact on snow microphysics will be discussed.