Typhoon Dujuan leaves thousands of households in Japan without power

On Monday, 21 September 2026, Typhoon Dujuan struck or threatened eastern Japan with powerful winds and exceptionally heavy rainfall. Conditions worsened through the day around Greater Tokyo and neighbouring Chiba Prefecture. The Japan Meteorological Agency warned of flooding, landslides and dangerous gusts. Power cuts were already being reported, with media reports saying that more than 4,000 households in Chiba were without electricity at one point.

Live outage information from Tokyo Electric Power Company Power Grid also showed interruptions in Chiba and Shizuoka on Monday. The figures changed as crews restored some supplies while new faults appeared. That is typical of weather-related network damage: one section may be re-energised while branches, falling trees, damaged poles or flooded equipment create a fresh fault elsewhere. A reliable final number of affected customers is therefore often impossible to establish until the storm has moved away.

Dujuan was far more than an electricity problem. At least 275 flights were cancelled, some railway services were suspended and major events were brought to an early end. The weather agency warned that rainfall through Tuesday could, in some places, exceed the average amount normally received during the whole month of September. Particularly serious warnings applied to the Izu Islands and parts of the Kanto region. These conditions also slow electricity repairs because crews cannot safely reach every damaged location during violent winds, flooding or landslide danger.

For households, the most important lesson is simple: a weather-related power cut may be forecast as a risk, but its exact start and duration remain unpredictable. When a typhoon, storm or extreme-rain warning is issued, there are often still several hours in which to charge power banks, place torches where they can be reached, minimise unnecessary opening of refrigerators and freezers, and save essential information offline. Drinking water, necessary medicines and some cash should also be easy to access.

Food refrigeration deserves particular attention. Official food-safety authorities warn that an unopened refrigerator remains sufficiently cold for only a limited time during an outage, while a well-filled freezer can hold a safe temperature considerably longer. Before severe weather arrives, spare freezer space can therefore be filled with frozen water containers or freezer packs. They add thermal reserve and reduce the need to improvise once the electricity has already failed.

There is another practical problem that is easy to underestimate during a severe storm: warnings and outage information can change quickly. Anyone relying on a single app or website may miss important updates if mobile data becomes weak or overloaded. It is better to have several information routes, such as local alerts, a battery-powered radio and telephone numbers for the network operator or local authority written down in advance. Families should also agree what to do if calls and mobile data stop working temporarily.

Japan's experience also shows why power-cut preparation and severe-weather preparation belong together. Thinking only about lighting overlooks other consequences: mobile networks may become congested, lifts stop, pumps fail and roads can become impassable at the same time. The problem is then not only the lack of electricity but also the reduced ability to obtain replacements or help quickly.

Typhoon Dujuan is not an example of a nationwide blackout. It illustrates a more common reality: extreme weather can create thousands of individual network faults and disconnect communities for hours at a time. Precisely because these outages are local and constantly changing, useful preparation starts before the first line fails.

Sources: Japan Meteorological Agency; Tokyo Electric Power Company Power Grid; Reuters; AFP. Updated: 21 September 2026.