This paper presents the public provision of information as a policy tool both for managing water use and for encouraging the development of the agricultural sector. It demonstrates that there is a theory-based justification for the use of public weather information systems as an environmental policy tool if the following two conditions hold: 1. Agricultural production systems are information intensive, and 2. information has public good components. It is found that public provision of weather information can reduce wasted water and increase agricultural output and economic viability, providing a tool that simultaneously addresses concerns about development and the environment. Lessons learned from the impact of a weather information system in California are reinterpreted for a similar system in the developing country context of Mexico.