STRUCTURE AND EVOLUTION OF WINTER CYCLONES IN THE CENTRAL UNITED-STATES AND THEIR EFFECTS ON THE DISTRIBUTION OF PRECIPITATION .3. THE DEVELOPMENT OF A SQUALL LINE ASSOCIATED WITH WEAK COLD FRONTOGENESIS ALOFT

From 8 to 9 March 1992 cold frontogenesis aloft (CFA), which was assoc iated with the development of a vigorous baroclinic wave, triggered a series of squall lines that produced large hail and several tornadoes as they moved across the central United States. The air lifted by the CFA, which produced the squall lines, was made potentially unstable as a result of the circulation associated with a surface drytrough. This study provides further support for the view that in winter and early spring CFA plays an important role in triggering severe weather in the central United States.