Several regions of South America are affected by teleconnections already discussed in previous studies. The Pacific South America (PSA) pattern, which is the main tropical –extratropical teleconnection in the Southern Hemisphere, affects the precipitation and temperature in southern and southeastern South America. In the summer, this pattern has influence on South Atlantic Convergence Zone (SACZ), increasing or reducing convection, through the action of one of the wavetrain centres of action that is established over southern South America. The Southern Annular Mode or Antarctic Oscillation has also influence on South America. These patterns are identified as the dominant modes of variability in EOF analyses and are well represented in model simulations. In this study these two patterns are analyzed in simulations of present climate, comparing to reanalysis results and showing the influences over South America. Extreme precipitation over Southeastern and Southern regions has been related to these patterns in previous studies. The feature to be investigated is related to the future influence of these patterns on the extremes. Will changes in a warmer climate affect these influences? Projections for the future climate using CMIP-5 results will be analyzed to investigate changes in the intensities or in the main modes of variability and their influence over South America.