Tropical Storm Champi is likely to become a typhoon within 24 hours, Taiwan's Central Weather Administration says, Focus Taiwan reported on October 16. Forecasters said they could not yet say where the storm will head after the middle of next week.

The storm is still thousands of kilometres from the island. Weather models disagree on whether it will veer north well away from Taiwan or move closer to it, so the authorities have yet to determine what risk it poses.

At 2pm local time on October 16, Champi was 3,600 km east-southeast of Eluanbi, the southernmost point of Taiwan. It was travelling west-northwest at 25 km per hour, according to the CWA.

CWA data showed the storm carrying maximum sustained winds of 100 kph, with a radius of 150 km.

CWA forecaster Tseng Chao-cheng said conditions around the storm favoured further strengthening. He added that Champi could grow into a severe typhoon.

The CWA expects the storm to track west to northwest over the coming five days. It is forecast to reach the seas south of the Ryukyu Islands on around October 20 or 21, then slowly bend northward on October 22.

Tseng said forecast models were split on the route Champi would take after that point. Some showed the storm turning north while still over waters south of the Ryukyu Islands, while others placed it nearer to Taiwan.

According to Tseng, how far Champi curves north will hinge on the eastward retreat of the Pacific high-pressure system. He said forecasters would need to follow the storm's movements closely around October 22 to judge what effect it might have on Taiwan.