9421847 Fovell Thunderstorms are of interest because of both the severe weather and the beneficial rainfall that they produce. A certain class of thunderstorms, known as multicellular storms, are very common in the Spring/Summer months and typically are not severe, but bring much needed rainfall. As their name implies, these storms are composed of a sequence of individual updrafts ( cells ) and their concomitant precipitation. While much have been learned about the behavior of multicellular storms, a few fundamental problems still remain. One such problem is that the factors that control the periodicity of cell formation and their temporal behavior have never been determined. Using an advanced numerical model, the Principal Investigator will attack this problem. Additionally, he will investigate how these storm modify their upstream conditions and, hence, potentially the future evolution of the storm. A third area of investigation is to study the structure and evolution of sea-breeze fronts and their role in convective initiation. While on the surface sea-breeze fronts and multicellular storms are quite different, they do share dynamic similarities that make these studies related. If successful, this research will lead to much improved understanding of the underlying dynamics of the ubiquitous multicellular thunderstorms. ***
