Adverse weather poses a significant threat to transportation safety. Road weather information systems (RWIS) are used to mitigate the impact of adverse weather. Because of the lack of detailed, unified guidelines and because of diverse weather conditions across the United States, state and city transportation agencies follow different practices for choosing locations for environmental sensor stations. This paper proposes a comprehensive cell-based methodology that optimizes overall benefits of RWIS based on weather-sensitive crash characterizations and using both normal and adverse weather crash data. The proposed approach is especially suited to optimizing regionwide environmental sensor station locations involving many road segments. A case study concerning RWIS deployment in Austin, Texas, was conducted with data from a crash records information system for 2010 to 2013.