In the present paper, using the data obtained by Reanalysis we identify the main patterns of atmospheric circulation in South America. For the processing of information, we made not distinction between El Niño, and No El Niño years, considering only averages of the main meteorological variables for the patterns identification. By analyzing the graphs of atmospheric pressure and winds, it was identified that the surface circulation is governed mainly by the presence of anticyclones in the Pacific and South Atlantic, and high levels of the system called Alta Bolivia, whose influence is seen from 500 hPa. On the other hand, the rainfall patterns highlight the Intertropical Convergence Zone, ITCZ, the Convergence Zone of the South Atlantic, SACZ, and the coastal deserts are located along the coasts of Peru and Chile. The ITCZ oscillates near the Equator, with maximum values of precipitatio...

Extreme rains have been observed in the north of Peru, the impact of these rains over the present infrastructure in the cities is important, this due to the high vulnerability of the zone. The events happen mainly in summer. Therefore, fourteen cases of extreme rain have been selected, those that registered during the December and March of 2001 and 2002. In the present research an evaluation of the numerical rain simulation is made in north of Peru. Use a regional model atmospheric call RAMS (Regional Atmosphere Modeling System). It has been implemented in the North zone of Peru using the nesting technique to reduce the resolution. The evaluation of the rain simulation is made measuring the correlation between registered rains and the simulated ones by the model RAMS. The results show a greater correlation for the high river basin, an intermediate value of correlation for the average riv...