Under this award the Principal Investigator will perform research on the initiation and evolution of convective storms. The goal is to advance fundamental knowledge of the kinematic, dynamic, and thermodynamic processes in convection initiation and evolution in order to improve the accuracy of storm prediction by operational forecasters. Since the consequences of convective storms can be severe, an increase in predictive capability will serve both public and commercial interests.
Boundary layer convergence lines (boundaries) is a focus of this research. During the past fifty years, the role of these boundaries in processes related to convection has been investigated. Gust fronts, sea-breeze fronts, cold fronts, drylines, and other boundaries, for example, have been associated with the initiation of convection. Further, the evolution of convection has been hypothesized to be related to boundary characteristics. This research emphasizes investigation of the role of boundaries in convection initiation and evolution. The specific objectives are to: 1. Determine the kinematic, dynamic, and thermodynamic fields associated with the development of horizontal shearing instabilities along thunderstorm outflow boundaries and the role of these instabilities in convection initiation. 2. Characterize the kinematic, dynamic, and thermodynamic structures associated with boundary collisions and the effect they have on convection initiation and evolution. 3. Determine the kinematic, dynamic, and thermodynamic processes involved in convective cell mergers. These objectives will be pursued by testing specific hypotheses using high quality Doppler radar, surface mesonet, balloon sounding, and aircraft data from the 1991 Convection and Precipitation! Electrification (CaPE) experiment in east-central Florida. This program was conducted in a region ideally suited to the topics addressed in this research and involved a wide range of ground-based and airborne data collection instruments. Two analytical approaches will be pursued. Objectives 1 and 2 will be investigated through limited analysis of numerous cases to test research hypotheses in a statistically significant manner. Objective 3 will be investigated through an in-depth, case study approach.
iii
