Tropical storm Cempaka strengthened early Tuesday over the South China Sea. It was located 185  kilometers southwest of Hong Kong as of 5 a.m. with wind speed up to 120 kph, according to CNN.

Cempaka is likely to weaken as it approaches land. The Hong Kong Observatory's typhoon warning signals has issued Strong Wind Signal No. 3 which indicates wind speed of 41 to 62 kph, the report said.

In-Fa is moving northwards and its impact will be on Japan's southern islands and Taiwan.

It is expected to bring rain to Japan ahead of the Olympic Games, which start in Tokyo on Friday, CNN reported.

Cempaka is expected to make landfall near the city of Yangjiang in China's Guangdong province, bringing heavy, flooding rains to southeastern portions of the country throughout this week.

Strong, gusty winds, especially near the coast where the storm will make the landfall are expected and may lead to power disruptions.

In-Fa will strengthen to a typhoon by midweek as it moves towards Taiwan.

It will blow over the north of the island, bringing the much needed rain as Taiwan is going through the worst drought in more than 50 years.

It will then make landfall over China late Saturday night into early Sunday morning hours local time along the coast of central Fujian province.