Comparison of Methods for EstimatingThunderstorm Cloud-Top Heights

This paper presents a comparison of three methods for determining cumulonimbus (Cb) cloud-top heights. Two methods are prognostic, based on the 1/4 CAPE and 1/2 CAPE approaches, while the third is a diagnostic polynomial method. The analysis was conducted for five convective events that developed under different synoptic and mesoscale conditions. Surface and upper-air synoptic charts, WRF simulations, radar, and radiosonde data, as well as observed lightning data are used to characterize the convective environments and evaluate the methods. The polynomial method, which approximates moist adiabats using a fifth- degree polynomial function, proved to be successful in diagnosing the Cb cloud-top heights at the observed locations. Therefore, cloud-top heights obtained from the polynomial method are used as a reference values for assessing the performance of the prognostic methods. Results show that, for most locations and events, both CAPE-based methods tend to overestimate Cb cloud-top heights. The 1/4 CAPE method generally exhibits smaller deviations from the observed values of Cb cloud-top heights than the 1/2 CAPE method. Nevertheless, the Cb cloud-top heights estimated using both CAPE methods exhibit a strong linear correlation with observed heights in four out of five analyzed events.