A Severe Southwest Desert Thunderstorm: 19 August 1973

Abstract

Intense thunderstorms, which frequent the desert Southwest of the United States in the summer months, have been known by several different names: chubasco, haboob, and Sonora storm. Prior to the advent of satellites and radar, the sparsity of observations in the desert Southwest precluded any determination of where these storms developed, as well as information on their areal coverage and life cycle. A particularly severe and long-lasting thunderstorm occurred 19?20 August 1973. This storm was followed through its life cycle by means of radar, satellite, and surface observations. This particular storm was noteworthy for its very strong winds, locally heavy rain, and the magnitude of the pressure jump associated with it. The converging of two separate mesohighs is believed to be the cause of the very intense storm that moved westward across the Imperial Valley of Southern California.