This paper uses state-level data on migration flows between Mexico and the U.S. from 1999 to 2011 to investigate the migration response to climate shocks and the mitigating impact of an agricultural cash-transfer program (PROCAMPO) and a disaster fund (Fonden). While lower than average precipitations increase undocumented migration, especially from the most agricultural states, Fonden amounts decrease the undocumented migration response to abnormally low precipitations during the dry season. Changes equalizing the distribution of PROCAMPO and favoring vulnerable producers in the non irrigated ejido sector mitigate the impact of droughts on migration, especially for a high initial level of inequality.