Weather Extremes in Indigenous Communities in Mexico and Undocumented U.S. Migration and Its Duration

In Mexico, the context of indigeneity—the share of the local population with precolonial origins—patterns multiple forms of inequality, including disproportionate exposure to weather extremes. We examine whether it also shapes undocumented migration to and return from the United States following weather extremes. Analyzing data on over 90,000 individuals from 147 Mexican communities in the Mexican Migration Project, linked to municipal measures of indigeneity from the Mexican Census and high-resolution daily precipitation and temperature data from Daymet, we estimate linear probability models. Results show that very dry years are associated with a higher probability of undocumented migration from low-indigenous municipalities, while extreme weather is associated with a lower probability of return to Mexico across all contexts of indigeneity. These findings suggest that weather deviations reinforce inequalities in international migration while broadly constraining return. We conclude that migration is a process shaped by overlapping social and environmental inequalities.