Late-season heat records fall in Tokyo and Osaka
Both cities exceeded 30 C, with Osaka surpassing a record that dated to Oct. 20, 1933.
Tokyo and Osaka registered temperatures above 30 C later in the calendar year than ever previously measured in either city, according to a Japanese weather official. Warm, humid air arriving from the south brought unusually high temperatures for late October, particularly along Japan’s Pacific coast.
The capital passed 30 C by early afternoon, said Kazuhiro Shirono, a data science official at the Japan Meteorological Agency (JMA). Tokyo’s weather records start in 1875; its previous latest date for such heat was Oct. 19, 2024. Osaka’s observations started in 1883, and its previous mark was Oct. 20, 1933.
The JMA calls a day reaching the 30 C threshold a “midsummer day.” The agency also introduced the term “kokushobi,” translated as “cruelly hot day,” for temperatures of 40 C (104F). It urged people to view extreme heat as a natural disaster.
Scientists attribute increasingly frequent and intense extreme heat worldwide to human-induced climate change. Japan’s summer in 2025 was its hottest on record.
