Effective climate adaptation in sub-Saharan African agriculture will require coordination across multiple scales of governance. Decision-makers from local to national scales will be tasked with planning under conditions of high uncertainty, often with minimal data. Participatory scenario planning is a method for devising adaptation strategies under high uncertainty, and we hypothesized that it could also be used for identifying systemic, inclusive, and transformative adaptation options at the community scale, and for highlighting opportunities for cross-scalar collaboration. We conducted scenario exercises with two communities in southeastern Nigeria that have experienced increasing flooding and other challenges linked to climate variability. Both communities identified drivers of change that intersect with climate, as well as community-scale actions that would improve adaptation to a range of future scenarios. We found evidence that scenario exercises can stimulate communities to develop transformative approaches to climate adaptation that seek to reduce climate risk by creating new systems and processes. We also found that community-identified priorities for strategic action highlight how larger-scale interventions could coordinate with communities to adapt more effectively. Participatory scenario planning is therefore a potentially important tool for adaptation planning in regions in which future conditions are highly uncertain.