FP2 Boundary Layer Events in the Plains Elevated Convection at Night (PECAN) Campaign

The Southern Great Plains of the United States is subject to strong storms during warm months, and prediction of these events is crucial for local agriculture and population centers. Such continental, nocturnal, warm-season rain events are not very well understood or predicted, however. This need for further study was addressed with the Plains Elevated Convection at Night (PECAN) field campaign during June 1 to July 15 of 2015. PECAN was a large multi-agency project including instrumentation and personnel from the NSF, NASA, NOAA, DOE, and universities. PECAN operations focused on intensive observation of convective rain and related atmospheric events, particularly nocturnal convection with a stable boundary layer, nocturnal low-level jets (NLLJs), and the largest convectively available potential energy above the boundary layer.

This presentation focuses on case studies from observations at a fixed site (FP2) in Greensburg, Kansas, near the center of the campaign domain. The events in question include outflow bore waves and NLLJs transporting moisture. The case studies are approached with a suite of instruments including Doppler lidar, water vapor lidar, a radiometer, radiosondes, and surface measurements to capture a wide range of atmospheric parameters. The Doppler lidar will not only provide winds, but also mixing layer heights via a new fuzzy logic algorithm. An overview of this retrieval algorithm and its innovative features will be presented. This presentation will also include preliminary results of a study addressing vertical wind speeds during LLJs. The overall goal of analyzing these diverse measurements is to improve understanding of the dynamics and thermodynamics of the phenomena in question, hence allowing for improvements in forecasting.