How does the public react to information about the likely progression of COVID‐19 cases in the United States? How do these reactions vary over the course of the pandemic and by partisanship, and with what consequences for policy attitudes and personal behavior? We argue that reading projections about the peak of COVID‐19 cases in the United States is likely to lead to increased levels of anxiety and sadness. We expect that these effects will be more pronounced and less polarized along partisan lines earlier in the pandemic. Finally, we expect that elevated anxiety and sadness should in turn lead to greater support for protective policies to combat the pandemic and a greater inclination to engage in protective behaviors. To test these arguments, we fielded online survey experiments at three points in time (April, June, and August 2020), in which respondents were randomly assigned to a control group or one of two projections about the likely progression of COVID‐19 cases in the United States. Across all three waves, we find that exposure to information about case peaks increases anxiety and sadness, though the effects get weaker over time, particularly among Republicans. We also find evidence that these elevated emotional responses increase support for protective policies and behavior.