Pico de Tancítaro National Park is the most important source of water for the collection and recharge cycle of the aquifers located in western region of the state of Michoacán. Understanding the precipitation variability throughout time is crucial. Nonetheless, there is a lack of extensive and quality series on climatic data. For this reason, this work established the following objectives: 1) to reconstruct the precipitation variability for Pico de Tancítaro National Park based on the Abies religiosa growth rings, and 2) to analyze the drought frequency during the XXth century and the first decade of the XXIst century. Thus, some A. religiosa samples were taken and dated using standardized dendrochronological techniques. The quality of the dating as well as the quality of its climatic response were verified with the COFECHA software. These series presented a significant correlation (r=0.473; P < 0.01), which indicates their potential to generate dendroclimatic series. The precipitation of the last 127 years (1884-2010) was reconstructed. The severest droughts were reconstructed for the 1890-1896, 1948-1956, 1967-1971, 1982-1989, and 1998-2004 periods. It was also found that the Paricutín volcano eruption (1943) had a significant effect on regional climate.

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