Tokyo, Osaka, Nagoya hit latest-ever October 30°C days

On October 21, 2026, Japan experienced unseasonably warm weather as warm air from a Pacific high-pressure system flowed across the country's Pacific coast. Tokyo's central district (Chiyoda Ward) reached 30.3°C, Osaka's Chuo Ward hit 31.2°C, and Nagoya's Chikusa Ward reached 31.4°C—all marking the latest dates on record for reaching 30°C or higher. The Japan Meteorological Agency confirmed these broke previous records: Tokyo's previous latest was October 19, 2024; Nagoya's was October 17, 2024, and October 17, 1961; and Osaka's was October 20, 1933.

The heat extended across Japan, with 155 to 157 observation stations nationwide recording temperatures of 30°C or higher by mid-afternoon. Hyuga in Miyazaki Prefecture recorded the nation's highest temperature at 33.6°C, followed by Kofu in Yamanashi Prefecture at 33.5°C and Kihoku in Mie Prefecture at 33.0–33.2°C. Other notable readings included Hachioji in Tokyo at 32.4°C. The temperature spike was driven by warm air flowing from a high-pressure system toward a low-pressure area, combined with clear skies that allowed direct sunlight to further elevate readings.

The unseasonable heat presented a stark contrast to northern Japan, where cold air brought markedly lower temperatures. In Hokkaido's interior, several locations recorded single-digit highs: Hokkakawacho Asshmaroi reached only 9.5°C, while Asahikawa recorded 10.9°C—the season's lowest maximum temperature in that city. Strong winds in the north further lowered the felt temperature.

Meteorologists predicted a rapid cooling trend on October 22 as a cold front moved south. Tokyo, Nagoya, and Osaka were forecast to drop to around 23°C, with few locations exceeding 25°C despite clear skies in western and eastern Japan. Northern Japan's Sea of Japan side was expected to see rain, with Sapporo reaching only 10°C and Asahikawa dropping to 8°C, necessitating heavy outerwear.