Analysis of Cold Pools’ Morphology and Thermodynamics in Connection with Associated Convective Clouds Strength and Microphysics Evolution

There is a clear importance of understanding the roles of convective cold pools, and properly representing those processes in multi-scale meteorological models. In particular, the strong coupling between convective initiation and maintenance, cold pool forcing of vertical velocities, and surface-based outflows is not well represented in multi-scale models. The main goal of this work is to study the relationships between the morphological and thermodynamical properties of cold pools with the different stage of the storm lifecycle; in particular, with the updraft/downdraft strength and microphysics characterization of convective clouds’ evolution.

This analysis is centered around deep convective systems and their associated cold pools that took place on May 23, 2011. Dataset analyzed corresponds to the Oklahoma Mesonet observations, NEXt-generation RADar (NEXRAD) and the Department of Energy-Atmospheric Radiation Measurement (DOE-ARM) and National Aerospace and Space Administration (NASA) radar networks and the vast amount of observations available from the Midlatitude Continental Convective Clouds Experiment (MC3E).

The observational analysis of reflectivity composite from KTLX and KVNX NEXRAD radars and temporal and spatial evolution of surface variables, such as temperature and humidity from both the Oklahoma MESONET and the DOE-ARM surface station networks, led to the satisfactory detection of cold pools for this day. Different cold pool detection techniques, from thermodynamics to a purely kinematic methodology, were evaluated and corroborated manually with the observations from NEXRAD, DOE-ARM and NASA radar networks. RHI scans from the C-band Scanning ARM Precipitation Radar (C-SAPR) provided further information of the vertical structure of the cold pool at fine vertical resolution as well as attendant kinematic and hydrometeor evolution of the convective clouds in the cross-sectional plane. The potential role(s) of hydrometeor evolution on cold pools lifecycle, and subsequent feedbacks onto the convective evolution and the formation of new convection during this day were also explored via hydrometeor classification from the KVNX NEXRAD polarimetric datasets.