July 17 (Bloomberg) -- Super Typhoon Haitang's winds strengthened to as much as 196 mph (315 kph) as it heads across the Pacific Ocean toward Taiwan's east coast, where it is expected to make landfall tomorrow morning.

Haitang, the fifth tropical storm of the Pacific's typhoon season, has sustained winds of 161 mph and its center was about 500 kilometers (310 miles) east south-east of the city of Taitung at 8 a.m. Taiwan time this morning, according to the latest advisory on the U.S. government's Joint Typhoon Warning Center Web site.

Japan's Meterological Agency issued a warning at 2:05 p.m. Tokyo time of the possibility of a large storm surge and strong winds for the southern islands of the Okinawa island chain near Taiwan. Wave heights are as high as 50 feet (15 meters) around the center of the storm, the Typhoon Warning Center said.

Taiwanese authorities yesterday issued a sea alert for Haitang and warned citizens to make preparations for the approaching typhoon, which will bring strong winds and heavy rains and may cause landslides.

Haitang is moving west north-west at about 14 mph and the center of the storm will probably cross the Taiwanese coast sometime after 8 a.m. on July 18, the Typhoon Warning Center said.

Sustained winds are forecast to decline to 155 mph with gusts as high as 190 mph by 2 p.m. today, the Typhoon Warning Center said.

To contact the reporters on this story: Aaron Sheldrick in Tokyo at asheldrick@bloomberg.net; Mari Murayama in Tokyo at mmurayama@bloomberg.net

Last Updated: July 17, 2005 02:50 EDT