Typhoon Wipha's 32 Inches of Rain Kills 17 in Japan

Typhoon Wipha roared past Japan on Tuesday as a Category 1 typhoon, bringing destructive winds and high rains that triggered flooding being blamed for at least 17 deaths. Most of the deaths occurred on Izu Oshima island, about 75 miles south of Tokyo. An astonishing 32.44" (824 mm) fell in just 23 hours on the island, triggering flash floods and mudslides that killed 16 people and left 50 missing. During one incredibly wet 6-hour period, 549.5 mm fell, setting a new 6-hour precipitation record for Japan. The previous record was 502.0 mm at Tarama, Okinawa, on April 28, 1988. According to weather records researcher Maximiliano Herrera, the 24-hour total at Oshima Island was the third highest 24-hour rainfall for Japan on record; the record is 851.5 mm at Yanase (Kochi Prefecture) on 19 July 2011, and 2nd place is the 844 mm that fell at Takeshi (Nara) on 1 August 1982. Tokyo received 9.69" (246 mm) of rain in 19 hours from Wipha, with winds that reached 50 mph, gusting to 72 mph. At the time Wipha was deluging Tokyo, the typhoon was merging with a cold front and undergoing the transition to an extratropical storm--the same process Hurricane Sandy underwent as it approached landfall in New Jersey in October 2012. The counter-clockwise flow of air around the center of Wipha lifted up copious amounts of tropical moisture over a cold front over Japan, resulting the near-record rainfall amounts observed.


Figure 1. A house and an electric pole smashed by large rocks from a collapsed slope caused by heavy rain in Kamakura, suburban Tokyo on October 16, 2013. JIJI PRESS/AFP/Getty Images


Figure 2. Extreme rainfall of 33.44" in 24 hours from Typhoon Wipha hit Oshima Island, Japan, about 75 miles south of Tokyo, on October 16, 2013. At least 16 people died in this landslide, and 50 are missing. JIJI PRESS/AFP/Getty Images

Tropical Storm Francisco is headed towards Japan
It's been an active October for typhoons in the Western Pacific, and there is at least one more typhoon on the way. Tropical Storm Francisco has formed in the waters east of the Philippines, and is forecast to become a major Category 4 typhoon by Sunday as it heads north-northwest towards Japan. Both the GFS and European models predict that Francisco will come very close to Japan on Wednesday, October 23. Satellite images show that Francisco has already developed an impressive area of heavy thunderstorms with very cold cloud tops, and is strengthening. Francisco's formation gives the Western Pacific 27 named storms so far in 2013. That is the average number of named storms the Western Pacific sees during an entire year. The last time there were more than 27 tropical storms or typhoons in the West Pacific was in 2004, when there were 32.

Wipha's place in history
Wipha is the fourth named storm to hit Japan so far in 2013, and the deadliest typhoon to hit Japan since Typhoon Tokage of October 2004. The other named storms to hit Japan in 2013 were Tropical Storm Man-Yi on September 16, Tropical Storm Toraji on September 4, and Typhoon Danas, which hit Okinawa on October 7. An average of 2.8 tropical storms or typhoons per year hit Japan during the period 1951 - 2003. Japan's record busiest year was 2004, when ten named storms hit, six of them at Category 1 or higher strength. Jeffrey Hayes has put together a nice summary of Japan's typhoon history. The CIMSS Satellite Blog has an interesting analysis of Wipha.

The Atlantic is quiet
None of the reliable computer models for forecasting tropical cyclone genesis is predicting development over the next five days. NHC is giving 10% odds that a blob of disturbed weather near Bermuda headed north to northeast out to sea will develop.

Jeff Masters