Tokyo logs 35 consecutive days of rain as September precipitation exceeds 690 mm

Longest rain streak since 1886

Tokyo recorded its 35th consecutive day of rain on 30 September, exceeding the previous streak of 33 days measured between 27 June and 29 July 2019. The Japanese capital has not had a completely dry day since 27 August, marking the longest continuous precipitation run since modern observational records began in 1886. Weather monitors in central Tokyo measured 629 millimetres of rain from the start of September through Monday, reaching 692.5 millimetres by 9:00 on 30 September. That volume is more than three times the 224.9 millimetres recorded as the monthly climatic average for the 1991–2020 baseline period. Sunlight levels dropped sharply across the city, with the Japan Meteorological Agency recording 45.8 hours of sunshine in September, which represents roughly 40% of the usual seasonal average and the second-lowest total on record. During that timeframe, the sun failed to appear at all on 14 separate days.

Atmospheric drivers and Pacific warming

The prolonged weather pattern resulted from a seasonal autumn rain front, known as the akisame zensen, which remained stalled over and adjacent to the Japanese archipelago. A sequence of tropical cyclones, including typhoons 24, 25, and 26, continuously funnelled warm, moisture-laden air from the Pacific into the stationary boundary. Atmospheric circulation was further altered across continental and oceanic scales by an active El Nino event in the Pacific. Equatorial sea surface temperatures monitored by the meteorological agency in July ran 2.5 degrees Celsius above normal, matching the July record set in 1997. Japan Meteorological Agency official Masayuki Kyoda explained the stalling weather system.

Autumn rain fronts are staying longer than usual.

Economic effects and daily disruption

Heavy rainfall damaged crops across agricultural regions near Tokyo, driving wholesale prices for lettuce and other leafy greens to more than double their usual seasonal levels. Property maintenance services in the Tokyo metropolitan area saw requests for roof leaks and water infiltration climb to more than five times the volume seen in the same period of 2025. Persistent indoor humidity prevented residents from drying laundry at home, shifting demand toward commercial laundromats. Physical well-being also deteriorated under the prolonged cloud cover and high moisture. Hiromichi Ito, a physician and director of a clinic in Tokyo, noted that sustained rain, low atmospheric pressure, and elevated humidity cause headaches, dizziness, and related physical complaints.

Storm damage and regional outlook

The wider storm pattern brought severe consequences beyond the capital during late summer and early autumn. In early September, Typhoon Dujuan triggered widespread flooding and landslides in neighbouring Chiba prefecture, killing eight people and destroying dozens of residential structures. On social networks, discussions regarding rain fatigue circulated widely as residents reacted to weeks of grey skies. By late Wednesday, rainfall in central Tokyo eased to a light drizzle, though forecasters continued to monitor new weather disturbances developing over the surrounding Kanto plain. Forecasters also tracked the path of Typhoon 26 across the Pacific Ocean.