Resumen
In this paper, an analytical study of an explosive cyclogenesis that occurred in northeastern Argentina on 11-12 November 1989, is carried out. European Centre for Medium Range Weather Forecasts Analysis data are used to compute the terms of the atmospheric motion governing equations in order to determine the triggering mechanisms of this event. This cyclogenesis is initiated by classical processes such as the advection of vorticity and divergence in the upper troposphere. The diabatic mechanisms rapidly associate to these processes, generating an intense cyclonic potential vorticity in low levels and depleting it in upper levels. The major development occurs when the presence of cyclonic vorticity in upper levels continues in spite of the mechanisms tending to weaken it.