The Central Weather Bureau (CWB) yesterday issued a sea alert for Typhoon Tembin, adding that the nation would be pounded by strong winds and torrential rain from tomorrow until Friday.
As of 5:30pm yesterday, Tembin’s center was 470km southeast of Oluanpi (鵝鑾鼻), with the radius of the storm expanding to 180km. It was moving northwest at 11kph.
The sea alert applies to vessels operating near the nation’s northeastern and southeastern regions, as well as in the Bashi Channel.
The bureau said that 3m waves had already been detected on the nation’s southeast coast and Hengchun Peninsula yesterday.
Bureau forecaster Wu Wan-hua (伍婉華) said Tembin had the potential to turn into a stronger typhoon.
“Its impact will be most apparent all day on Thursday, and Friday morning. There will be strong wind and precipitation nationwide during this period,” Wu said.
The bureau said it could issue a land alert for Tembin today.
Based on the bureau’s forecast, the typhoon is likely to make landfall on the east coast.
It would move across the nation and reach the Taiwan Strait by Friday afternoon.
Meanwhile, Tropical Storm Bolaven was 720km northwest of Guam as of 5:30pm yesterday. It was moving northwest at 14kph. Based on the path forecast by the bureau, the storm is moving in the direction of Taiwan.
Wu said that whether Tembin and Bolaven would generate the Fujiwhara effect remained to be seen, adding that the bureau could better judge that after Bolevan moves closer.
The effect, named after the Japanese meteorologist who first described it, refers to an interaction of two nearby cyclonic vortices in which they orbit around each other or merge. The effect could prolong the time that Tembin lingers around the nation, bringing torrential rain and more damage.
According to the bureau, Tembin and Bolaven were still about 1,550km apart as of 6pm. In general, the Fujiwhara effect happens when two storms are less than 1,000km from each other.
Meanwhile, the bureau yesterday activated the Dropsonde Observation for Typhoon Surveillance near the Taiwan Region (DOTSTAR) project, in which an aircraft is dispatched to fly around a typhoon and collect information.
Former CWB forecast center director Daniel Wu (吳德榮) said that one cannot determine the potential for the Fujiwhara effect by looking only at a satellite cloud image.
He said that the bureau can use statistics collected by DOTSTAR to determine the possibility of the Fujiwhara effect.
While Tembin has yet to arrive, vegetable prices in the Taipei Vegetable and Fruit Market went from an average of NT$35.9 per kilogram on Sunday to NT$42.8 per kilogram yesterday. The market was closed on Monday.