This study analyses the relation between Low-Level Jets (LLJ) and Flows in the vertical wind profiles generating convection at the synoptic scale, and associated events of rainfall, using vertical wind profiles obtained by radiosonde at the Salgado Filho International Airport in Porto Alegre, the State of Rio Grande do Sul. The LLJs involved in this large-scale transport tend to be associated with nocturnal convective events and with the generation of Mesoscale Convective Complexes (MCCs), giving high rainfall intensities, which may have important economic consequences. To describe the relations involved, the study uses a statistical method principal component analysis. Use of this method makes it possible to understand the complex interactions operating at meteorological scales involved in synoptic processes, from macro- to meso-scale. In such complexity, the part played by LLJs and Flows in this interaction is to effect transport in the lower atmosphere, thereby coupling regional meteorology and water circulation at the continental scale.
low-level jet; principal component analysis; precipitation
