This research examines the extent to which four anticipatory emotional reactions (hope, anxiety, helplessness, and boredom) that arise when contemplating participating in public-sphere climate action predict intentions to engage in such action. In a large, geographically diverse sample of American adults visiting informal science learning centers (e.g., zoos, aquariums; N = 4964), stronger feelings of hope robustly predicted greater intentions to act (η²_p = .22, a large effect); whereas stronger feelings of boredom robustly predicted decreased intention to act (η²_p = .09, a medium effect). Both of these feelings had significantly more predictive power than political orientation (η²_p = .04, a small-to-medium effect). The extent to which respondents felt anxious or helpless was not strongly correlated with their intentions to take action (η²_ps ≈ 0.01, a small effect). These findings highlight the underexplored connection between how people feel when they contemplate taking climate action and their intentions to engage in such action.