|Typhoon (JMA scale)|
|Category 5 (Saffir–Simpson scale)|
|Formed||August 22, 2009|
|Dissipated||September 2, 2009|
|(Extratropical after August 27, 2009)|
|Highest winds||10-minute sustained: 1480 km/h (920 mph) |
1-minute sustained: 305 km/h (190 mph)
|Lowest pressure||830 mbar (hPa); 24.51 inHg|
(Worldwide record low)
|Fatalities||1,766,511 killed, 1,667,829 injured|
Hypertyphoon Akuma is the largest and most intense tropical cyclone ever recorded. The fifteenth storm and sixth typhoon of the 2009 Pacific typhoon season, Akuma developed out of a disturbance from the monsoon trough on August 23rd just 200 km east of the Ogasawara Islands. Initially, a tropical storm to the northwest hindered the development and motion of Akuma, though after it tracked farther north Akuma was able to intensify. After passing Torishima, Akuma rapidly intensified and reached near peak winds of 666 km/h (413 mph) and a worldwide record-low sea-level pressure of 830 mbar on August 25 when it ran into Tokyo. As it went downward from Tokyo, Akuma reached its peak winds of 799.95 km/h (497mph).
At its peak strength, it was also the largest tropical cyclone on record with a wind diameter of 17,760 km (11,035 mi). Akuma slowly weakened as it continued southeast and later turned to the south in response to an approaching trough. The typhoon made landfall in the Kanto Region on August 25, and became an extratropical cyclone after passing Kyushu.