Heavy Rain in Santa Catarina: Synoptic Analysis of an Extreme Event and Numerical Simulation Using WRF Model

Abstract

The extreme rainfall event in November 2008 in Santa Catarina is discussed in the present study. Due to the importance of the event, the objectives of this study are: i) discuss the large scale aspects of the raifall event and ii) perform a numerical simulation using WRF Model. Synoptic analysis results show that the heavy rainfall event was associated to the persistence of a blocking high during November 2008 and a cyclonic vortex in middle-levels. The analysis of time series of meteorological variables led us to identify the origin of these atmospheric disturbances and its decay, resulting in high accumulated precipitation between November 22nd and 24th. The WRF simulation results allowed the detailing of dynamical and thermodynamic conditions that contributed to the intensity of the phenomenon. Further, it allowed the identification of the organized precipitation over the coast, even though their intensity was underestimated.