Usagi not among top 10 most powerful historic typhoons
CNATAIPEI -- Super Typhoon Usagi, which was bearing down on Taiwan Friday, has been described as the most powerful storm anywhere in the world in 2013.
September 21, 2013, 12:07 am TWN
But when compared to other storms since Taiwan started to collect typhoon data in 1958, Usagi's maximum sustained winds of 198 kilometers per hour do not even rank in the top 10.
According to Central Weather Bureau data, Typhoon Nancy, which struck in 1961, was the most powerful storm ever to affect Taiwan, with maximum sustained winds of 360 kph and a radius of 650 km.
Another five typhoons — Grace in 1958, Joan in 1959, Opal in 1962, Sally in 1964 and Mary in 1965 — are listed as the second strongest storms in Taiwan's history with maximum sustained winds of 270 kph, according to the data.
Usagi will be one of the strongest storms to hit Taiwan in the past 20 years, however, trailing only Typhoon Doug in 1994, which had maximum sustained winds of 209 kph and a radius of 350 km, the data showed.
A number of other super storms — Fred in 1994, Ivan in 1997, Zeb in 1998, Haitang in 2005, Sangda in 2011 and Jelawat in 2012 — have had similar wind readings to Usagi during the period.
Cheng Ming-dean, head of the CWB's Weather Forecast Center, said typhoon intensity is generally correlated with El Nino, a phenomenon that describes the abnormal warming of water temperatures in the eastern Pacific that can cause unusual global weather patterns.
Typhoons tend to be stronger in “El Nino” years than in other years, he said.
Though the El Nino phenomenon has not yet appeared this year, water temperatures near Taiwan have been unusually high which may explain the intensity of recent storms, including Usagi, Cheng said.
The CWB issued a land warning for Super Typhoon Usagi on Friday, predicting heavy rainfall across the island.
As of 2 p.m., Usagi was centered about 440 kilometers east-southeast of Taiwan's southernmost tip, moving in a west-northwesterly direction at a speed of 18 km per hour. It had a radius of 280 km.
Meanwhile, Vice Premier Mao Chih kuo instructed all disaster prevention and control agencies to stay alert, take the necessary precautions and provide the public with complete disaster-prevention information.
Taiwan's Central Emergency Operation Center has warned local governments in Yilan, Taitung, Hualien, and Pingtung counties and Kaohsiung City of possible torrential rains based on weather forecasts.
The Ministry of National Defense has also set up its emergency center and ordered military forces to be on stand-by for rescue and relief missions.