ANALYSIS OF VERTICAL MOVEMENT IN TWO DIFFERENT CONFIGURATIONS OF HIGH-LEVELS OF THE TROPOSPHERE

The southern region of Brazil is potentially favorable the occurrence of extreme events, where these are due to different weather systems that operate in South America. Therefore various techniques have been exposed to improve the accuracy thereof, a characteristic what is present in many of them is the presence of troughs in the 500 hPa level. The present study aims to evaluate the vertical movement of two severe storm events that hit southern Brazil in the fall of 2013, one on 26 March and another on May 29, where both of them occurred from the same system type, but with different inclinations of the horizontal axis of the higher level trough of the atmosphere. For this were used data from the monthly compilation of significant cases of CPTEC / INPE for the choice of severe instability events. For the preparation of meteorological fields to be evaluated were reanalysis data used MERRA. This study showed that omega vertical upward movement was much more intense when related to the system associated with the negatively-trough (about 1.2 m s -1 ) while the upward movement associated with the positive-trough was around 0.5 m s -1 .