In this work we analyze the future evolution of maximum temperatures during the warm season (June-September) in the 53 cities of the Iberian Peninsula. Maximum temperature data obtained from the CORDEX project using 9 regional models were used, and from their simulations for the historical period (1980-2005) and for the two future periods: one near (2020-2049) and the other far (2070-2099), it was analyzed how the maximum temperature, the percentage of days with extreme events and the percentage of days under heat wave will vary based on two future scenarios, RCP 4.5 and RCP 8.5. It was observed that the 9 RCMs are valid to carry out this analysis since they show a similar degree of reliability.