Increasing environmental crises due to climate change calls for bridging the research and operational logics of spatial planning and humanitarian response. This article explores how long-term spatial planning and short-term humanitarian responses relate to three facets of uncertainty that are particularly relevant in developmental contexts, namely epistemic uncertainty, ontic uncertainty, and ambiguity. The authors explore these facets through a case study of uncertainty, that of unexpected monsoon floods in 2018 and 2019 in Wayanad, a peri-urban hill district in Kerala, India. Through the case, they show that compounded uncertainty leads to ambiguity in action, but that this ambiguity can be ameliorated by a contextualised contingency planning approach. The authors conclude the article by outlining the approach in spatial planning that prioritises flexible and adaptable decision-making to enhance iterative organisational learning and action, as well as cross-sectoral dialogue to deal with uncertainty. [ABSTRACT FROM AUTHOR]