Extreme Summer Weather Disrupts Solar Output Across Key Global Markets

Solar industry data firm Solargis reported that the summer of 2026 saw sunshine patterns diverge dramatically from historical averages in several leading markets. Southern England, western France, Malaysia, Indonesia and the southern Philippines recorded solar irradiance up to 30 percent above normal, while regions like eastern India, the US Midwest, southern Brazil, northern Argentina and Uruguay suffered deficits of 20 percent or more.

Northern Europe also faced up to a 25-percent shortfall due to excess precipitation. Marcel Suri, Solargis' chief executive, warned that such volatility challenges the accuracy of generation forecasts for wind and solar assets, creating risk for investors and grid operators. He emphasized that the investment case for renewables remains strong but calls for more detailed weather data to hedge against these swings. Financial firms, including Jane Street and Millennium Management, have responded by recruiting weather experts to better assess and mitigate climate-driven risks.