Japan endured its hottest June since records began in 1898, with the Japan Meteorological Agency reporting that the national average temperature was 2.34 °C above the 1991-2020 norm. The unusually strong Pacific high-pressure system, compounded by climate change, pushed readings well into midsummer territory weeks early and prompted officials to warn residents to guard against heatstroke. In Europe, Spain’s national weather service said Barcelona posted an average temperature of 26 °C, the highest for June in more than a century, with a single-day peak of 37.9 °C on 30 June. The record in the Catalan capital was part of a broader heat episode that saw France, Italy and other countries issue red-alert warnings and temporarily close schools and tourist sites. Data released by the EU-funded Copernicus Climate Change Service show Western Europe as a whole registering its warmest June on record, with an average of 20.49 °C (68.9 °F). Copernicus also calculated that, worldwide, June 2025 was the third-warmest in modern records, posting a mean surface air temperature of 16.46 °C—about 0.47 °C above the 1991-2020 average and 1.30 °C higher than the pre-industrial baseline. Elsewhere in Asia, 59 of South Korea’s 97 climate-observation stations chalked up historic June highs, underscoring the hemispheric breadth of the heat. Scientists at Copernicus and national agencies warn that a warming climate is lengthening the heat-wave season and increasing the frequency of extreme temperature events, raising health risks and straining power grids across multiple regions.