Explainer: What last week’s storm says about climate change

The Western Cape storm of May 10–11, 2026, was an unusually extreme event driven by a slow-moving cut-off low, multiple cold fronts, and record rainfall of 200–300mm over 48 hours. Hurricane-force gusts of 117 km/hr and saturated catchments from earlier rain worsened the flooding, which affected over 83,000 people and caused 10 deaths. The storm disrupted major routes, including parts of the N1 and mountain passes, while damaging over 21,000 dwellings and forcing school closures. It was described as the worst Cape storm since September 2023, with combined wind and flooding impacts stretching from the Garden Route to Cape Town. While cut-off lows are typical in the region, climate science suggests extreme rainfall events are intensifying due to warmer air holding more moisture. Southern Africa has recently seen destructive floods linked to climate variability and warming oceans, though individual storm attribution remains uncertain. Current climate models for the southwestern Cape indicate fewer cold fronts overall but potentially stronger rainfall during the most intense systems. Research also suggests cut-off lows may become less frequent but carry more moisture when they occur, mirroring trends in the Mediterranean. The storm’s severity aligns with broader trends of more damaging extreme-weather events, though long-term climate shifts differ from short-term anomalies. Scientists emphasize that while this storm’s exact link to climate change requires further study, global warming increases the likelihood of such intense rainfall.