Climatologist Christophe Cassou, a research director at CNRS and co-author of the sixth assessment report of the **Intergovernmental Panel on Climate Change (IPCC)**, has warned that if global temperatures continue to rise, predicting how rainfall patterns will change in France becomes increasingly uncertain. Following an unusually hot summer in 2026, the High Commission for Strategy and Planning hosted a webinar on September 30 to examine the lessons learned, with a focus on the increasing likelihood of more frequent and severe heatwaves and droughts. Cassou noted that while the 2026 summer was extreme, it fell within the range of possibilities outlined in climate models, making it a foreseeable outcome of current trends. Cassou emphasized that over the next twenty years, winter rainfall in France is unlikely to increase. This could change after 2050, particularly in a scenario where global temperatures rise by four degrees Celsius by the end of the century. In such a scenario, other climate impacts would become more pressing than changes in precipitation, as the planet would approach or exceed physiological limits for ecosystems and human health. Current projections indicate a wide range of possible outcomes for rainfall, with potential deficits ranging from -60% to +60%. Cassou suggested that the extreme summer of 2026 could become the new normal by 2070, shifting from an event that occurs once per century to one that happens roughly every ten to twenty years. The next decade, however, may bring even hotter summers, with average temperatures reaching 25 degrees Celsius (compared to 24 degrees in 2026), leading to 70 to 75 days of heatwaves each summer (compared to 53 this year). He urged policymakers to consider the probabilities of such conditions and to develop "transformational and systemic adaptation policies" rather than making only small, incremental changes. Cassou warned that some current economic or agricultural activities may no longer be viable under these evolving climate conditions. He called on policymakers to address the winners and losers of climate change to minimize the negative impacts on vulnerable populations. He concluded that the real challenge is to reform public policy to anticipate and prepare for climate change, rather than constantly responding to its effects as they arise.