After #BlackLivesMatter protests in summer 2020, many leaders in the US South reevaluated monuments dedicated to the confederate and segregation eras. Black affiliates of the University of Arkansas used the Twitter hashtag #BlackatUARK to demand the removal of memorials commemorating a segregationist senator and share their experiences of anti-Black racism on campus. We argue that #BlackatUARK provides a counterpublic memorial of campus life that opposes and transforms dominant public memories, geographies, and subjectivities. Our analysis of the hashtag expands the conceptual boundaries of the kairos/metanoia partnership to show how digital counterpublic memories gain momentum and produce tangible rhetorical effects across both digital and nondigital contexts. During its circulation, the hashtag opens and sustains a kairotic moment fueled by the exigent flow of memories of anti-Black racism on campus. Simultaneously, the hashtag ignites a metanoic moment whereby allies mobilize their regret about a shameful past to plan a more just future.