Very limited amount of research has been devoted to climate actions at the local level in comparison to those at federal and state levels. It is unclear why some cities acted as leaders in the fight against climate change, some acted as followers, while others remained laggards. This study critically examines the major hypotheses about voluntary local climate actions so that we can better understand factors affecting local political will to commit to climate actions. Understanding these factors will increase our ability to design policies and strategies that enable more local voluntary participation in climate actions. Applying a survival analysis to the participation of California cities in the U.S. Conference of Mayors’ Climate Protection Agreement, this paper explains the temporal and spatial diffusion of local political will to take climate actions. The analysis examines whether the timing of cities’ participation in the Mayors’ Agreement is associated with a broad range of characteristics, such as: local demographics; government form and size; political preference and environmentalism; local air quality and congestion level; and behavior of neighboring jurisdictions. Results support the importance of income level, political preference and environmentalism of the local communities, as well as a city’s administrative capacity and autonomy. Congestion relief seems to be an important co-benefit motivating cities to reduce greenhouse gas emissions. However, average education level does not seem to affect local political will to act on climate change, nor does per capita number of planning professionals. The importance of individual political leadership also does not seem to be supported by our analysis.