A Synoptic and Photographic Climatology of Low-Precipitation Severe Thunderstorms in the Southern Plains

Abstract

The occurrence of an unusual type of severe thunderstorm, difficult to identify by radar, has been documented in the Southern Plains. All of the three storms previously studied occurred near the dryline. Although tornadoes and large hail were produced, little rain was observed at the ground and there was no evidence of a strong surface downdraft; two were described as ?bell-shaped?. Ten more cases of this rare type of storm have been recently documented visually and on radar. A photographic and synoptic climatology of this class of storm, the low-precipitation severe storm, is suggested on the basis of an analysis of the comparison among 11 of these cases. It is found that these storms form in a supercell-like environment which is drier in the moist layer and more weakly sheared than that of well-documented supercells in Oklahoma. Implications of our findings and additional storm characteristics are discussed in light of the larger sample size.