About thirty typhoons form each year over the Northwest Pacific Ocean, of which typically about seven or eight pass over Okinawa Prefecture, and about three hit the Japanese main islands, especially Kyushu and Shikoku. But any region of Japan, including Tokyo, Osaka and Hokkaido can be visited by typhoons.
Most typhoons hit Japan between May and October with August and September being the peak season. Typhoons later in the season tend to be stronger than typhoons earlier in the season. In Japan, typhoons are numbered rather than being given a personal name. For example, the twelfth typhoon of the year is known as "typhoon number 12".
A typhoon moves at a relatively slow pace (around 20 km/h), and its path can be predicted quite accurately. Japanese media provides detailed typhoon coverage, informing the public about the predicted path, weather warnings and impact on transportation.
Strong typhoons often bring the region's transportation system to a standstill, with airplanes and trains being stopped and expressways being closed. In the past, catastrophic typhoons have sometimes caused hundreds of casualties, such as the Isewan Typhoon in 1959, which cost the lives of more than 5000 people. In recent decades, however, the number of people killed by typhoons has been much lower. The biggest dangers posed by typhoons are landslides and the sudden rise of water levels.

Japan (Vera) (1959, September 26-27)

external image Vera_24_aug_1986_0522Z.jpg

Typhoon Vera was the worst in Japanese history, killing 4,580 residents of Honshu Island and injuring an additional 40,000. 40,000 homes were also destroyed, making 1.6 million people homeless. Furthermore, the regional railway system was cut in 827 different places. Additionally, another typhoon occurred ten days earlier, killing 2,000 Japanese and Korean citizens.
A low pressure area between Guam and Chuuk slowly organized into a tropical storm on September 21. It then intensified into a typhoon the next day as it tracked northwestward. On the 23rd, Vera rapidly intensified, possibly reaching peak winds of 190 mph winds that day. The wind speed, which was measured by reconnaissance aircraft, are subject to dispute due to the unknown conversion factors. However, the super typhoon was very intense with a pressure of 896 mb.
Unlike most super typhoons, which weaken due to upwelling or other outside factors, Vera remained very strong, slowly weakening as it continued northward. Strong divergence aloft and continued warm water temperatures allowed Vera to remain the equivalent of a Category 5 on the Saffir-Simpson hurricane scale. On September 26, Vera struck the coast along the Kansai region of Japan with winds of 160 mph. The storm weakened over the Archipelago while rapidly moving the northeast, and re-emerged into the northern Pacific Ocean on the 27th as a minimal typhoon. It continued to the east, and became extratropical on the 28th.

Heavy storm surge combined with flooding, as well as extreme winds, caused the deaths of 4,464 people with 658 missing. Vast areas of crops were destroyed, sea walls ruined, roads and railways greatly damaged, and overflown rivers contributed to a damage estimate of $261 million (1959 USD, $1.67 billion in 2005 USD). The combination of the death toll and the great number of people left homeless contributed to large outbreaks of dysentery, gangrene, tetanus and other epidemics. The typhoon leaves the ground with many water puddles and rivers, which were the perfect breeding sites for mosquitoes. Hence, people were prone to fall ill due to the spreading of diseases such as malaria and dengue fever (from mosquitoes).