Japan is facing a major weather emergency as Typhoon Dujuan, the 25th typhoon of the year, moves toward the country’s eastern Pacific coast, bringing powerful winds and exceptionally heavy rainfall to the Kanto, Tokai and surrounding regions.

The Japan Meteorological Agency (JMA) has urged residents across the Izu Islands, Kanto, and Pacific-facing parts of Tokai and Tohoku to remain alert to flooding, landslides, overflowing rivers, violent winds and high waves. Parts of China have already been placed under Level 4 danger warnings for landslides, while heavy rain has caused flooding in several locations.

Storm closing in on Tokyo region

As of Monday morning, Dujuan was moving northward over waters southwest of the Izu Islands. By around 10 a.m. local time, it was reported roughly 100 km west-southwest of Hachijojima, travelling at about 25 km/h. The storm had a central pressure of around 960 hPa, with maximum sustained winds near 144 km/h and gusts reaching approximately 198 km/h.

The system is expected to pass near the Boso Peninsula in Chiba Prefecture, east of Tokyo, from Monday evening into the night.

The immediate concern, however, is not only the wind. Forecasts indicate a potentially dangerous rainfall event, particularly because parts of eastern Japan have already received substantial amounts of rain.

Rainfall raises flood and landslide concerns

JMA data cited in reports showed 387.5 mm of rain at Izu Oshima in the 24 hours through Monday morning, while Kimitsu in Chiba recorded more than 280 mm during the same period.

For the 24 hours through Tuesday morning, rainfall could reach:

  1. Up to 350 mm in Tokai 
  2. Up to 300 mm in Kanto and the Izu Islands
  3. Up to 200 mm in Tohoku

Forecasters are also watching for linear rain bands, which can produce concentrated bursts of extremely heavy rainfall over a relatively small area and sharply increase the risk of flash flooding and landslides.

Urban residents have been advised to take particular care around flooded roads and underground spaces, where rapidly accumulating water can create dangerous conditions.

Flights, trains and major events disrupted

The storm has already disrupted transportation during Japan’s five-day Silver Week holiday, when travel activity is typically high.

At least 275 flights were cancelled on Monday, including cancellations by Japan Airlines and All Nippon Airways. Railway operators have also suspended services on several routes in eastern Japan, while further disruption to high-speed rail services has been anticipated as the storm moves closer.

The weather has also affected major public events. The Tokyo Game Show cancelled its final day’s programme, while other sporting and entertainment events in the affected regions have faced postponements or cancellations.

El Nino adds a broader climate backdrop

Dujuan is arriving during a period of unusually strong El Niño conditions in the Pacific. NOAA’s Climate Prediction Center said on September 10 that El Niño was strengthening, with more than a 90% chance of a very strong event during the Northern Hemisphere autumn and winter of 2026–27. NOAA reported eastern equatorial Pacific sea-surface temperature anomalies above +3°C in August.

NOAA’s forecast gives a 75% probability that the October–December 2026 El Niño will reach a level classified as historic under its RONI measure.

However, it would be misleading to say that El Niño alone is responsible for Typhoon Dujuan or its rainfall. The storm’s immediate behaviour is determined by a combination of atmospheric and oceanic conditions, while El Niño is part of the wider Pacific climate background.

For now, Japanese authorities are urging people in vulnerable areas to closely follow local evacuation instructions and weather updates as Dujuan makes its closest approach to eastern Japan.

Original article