Typhoon Roke made landfall near Hamamatsu City in Shizuoka Prefecture at around 05:00 UTC (14:00 local time) on September 21, killing at least 11 people and bringing powerful winds and heavy rain to a large swath of Japan. Roke rapidly intensified from a category 1 typhoon into a category 4 typhoon on its approach to Japan but increased wind shear and colder waters weakened the storm just before it made landfall. According to the Joint Typhoon Warning Center (JTWC), Roke came ashore as a borderline category 1/category 2 typhoon before passing around 30 miles (50 kilometers) to the northwest of Japan’s capital, Tokyo, as it continued to track to the northeast. Winds of around 100 mph (160 kmph) were reported near the landfall point. Roke rapidly moved northeast across Japan’s main island of Honshu after coming ashore, affecting the densely populated regions of Chubu, Kanto and Tohoku and dumping heavy rain in Fukushima Prefecture, where the earthquake-damaged Fukushima Daiichi nuclear plant is located.
According to AIR Worldwide, insured losses from Typhoon Roke are expected to range between JPY12 billion (USD150 million) and JPY46 billion (USD600 million). AIR added that Roke was primarily a wind event, with Shizuoka Prefecture badly affected by wind damage. However, AIR said wind losses elsewhere were mitigated by Roke’s short duration and rapid inland weakening. Although the most readily available damage reports are currently from typhoon-induced flooding, AIR said precipitation from Roke was less than that from Tropical Storm Talas, which caused widespread flooding in Japan after it made landfall in the country on September 2.
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According to the Japan Meteorological Agency (JMA), typhoon force winds were reported near Roke’s landfall region and tropical storm force winds affected parts of the densely populated regions of Chubu, Kanto and Tohoku, including the capital of Tokyo. Data from the JTWC indicates Roke moved near the Tokyo metropolitan area, subjecting the city to strong winds and heavy rain. Officials said wind damage was reported near the landfall area with downed trees and power lines reported. According to an early estimate from the Japanese Fire and Disaster Management Agency (FDMA), around 250 properties suffered wind damage from Roke. At least 575,000 households lost power at the height of the storm and all forms of transportation were disrupted as several motorways were closed, hundreds of flights were cancelled and some bullet train services were suspended.
Reports said car maker Toyota suspended production at 11 of its plants in Aichi Prefecture. Operations at plants owned by Nissan and Mitsubishi Heavy Industries were also disrupted, officials said. In Tokyo, several businesses and schools closed early due to the severe weather from Roke and there have been isolated reports of downed trees in the city. Thousands of commuters were also stranded after several rush hour trains were suspended and fire officials said three people had been injured in the city. However, no significant property damage was reported in the capital.
The heavy rainfall associated with Typhoon Roke also triggered widespread flooding. More than 1.2 million people were advised to evacuate their homes in the prefectures of Aichi, Gifu, Hyogo, Miyazaki, Oita and Wakayama over flooding fears (although it was not immediately clear how many people had followed the advice). Reports said 11 people were killed in the prefectures of Aichi, Ehime, Kumamoto, Nagasaki, Iwate and Saga after heavy rain and flooding hit several parts of Japan. As much as 3 inches (80 millimeters) of rain per hour fell in parts of central Honshu, triggering flooding and several landslides.
Reports said the storm dumped 16 inches (400 millimeters) of rain in 24 hours in the southwestern prefecture of Miyazaki while widespread flooding was reported in Aichi Prefecture, with the city of Nagoya particularly badly affected. Officials reported road damage in Nagoya after floodwaters several feet deep inundated parts of the city. Meanwhile, some 180 people from 100 households in Hayakawa, Yamanashi Prefecture, were isolated as a mudslide cut off a main road to the town. The FDMA said more than 1,600 properties sustained flooding damage. According to EQECAT, flood damage is not included under the basic insurance policy in Japan, and the cover that is offered as part of an extended comprehensive policy has many exclusions and a low take up rate.
After tracking through central Japan, Roke raced towards eastern parts of Honshu and the earthquake-hit prefecture of Fukushima before exiting into the North Pacific Ocean. Strong winds and rainfall of up to 8 inches (205 millimeters) were reported in the region, triggering flooding and landslides in communities affected by the Tohoku earthquake and tsunami in March. Ahead of the storm, there were fears that Roke could pose more problems for the Fukushima Daiichi nuclear power plant, which was sent into meltdown by the Tohoku event, but officials said the plant weathered the storm without major incident. Tokyo Electric Power Company, the plant’s owner, said several cameras set up to monitor the facility were damaged, but there had been no further leaks of radioactive water or material into the environment.
Sources: Joint Typhoon Warning Center, WSI, Agence France Presse, Kyodo News, Reuters News, CNN News, AIR Worldwide
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