Tornadic environments in Mexico

Abstract

Tornadoes represent a significant threat to society. In Mexico, these natural hazards are common, principally from the end of spring until autumn, with a mean of around 45 events yearly (2013−2022). Although there is no official tornado database in Mexico with a proper tornado classification, it is known that supercell and non-supercell tornadogenesis is possible in the country. In this context, the present investigation examines the environments under 298 confirmed and validated tornadoes formed in the Mexican territory. Such analysis was made using the proximity-sounding approach with the ERA5 reanalysis dataset. In addition, using the k-means clustering method, three Tornadic Environment Types were found, each with specific characteristics. The first type is the most common environment, documented throughout the year, particularly during summer and the beginning of autumn. Intermediate instability conditions, without wind shear, and high humidity near the surface characterize it. The second type is observed in high altitudes during the spring, with relatively dry conditions and low unstable environments. The previous examples may relate to non-supercell tornadogenesis in different geographical regions and seasons. In contrast, the third type can be associated with significant tornadoes, an environment rich in instability and wind shear, concentrated in the northern portions of Mexico during spring. The findings of this research provide insights into increasing understanding of tornadoes in Mexico. Furthermore, it can be helpful to generate improvements in tornado forecasting at the national level, offering a range of tornadic environment types under which these natural hazards can develop. The clustering method results offer an alternative option for the classification of tornadoes in countries with little capacity for the official classification of these phenomena.