BEIJING, Sept. 3 (Xinhua) -- The State Flood Control and Drought Relief Headquarters on Tuesday evening activated a Level-IV emergency response to flooding in south China's Guangdong and Hainan provinces as typhoon Yagi has entered the South China Sea.

China's National Meteorological Center (NMC) forecasted that typhoon Yagi will move northwest to approach the east of Hainan Island, with gradually increasing intensity.

According to the NMC, the typhoon is expected to make landfall along the east coastal areas of Hainan and the west coast of Guangdong Province on Friday.

The center launched a yellow alert for typhoon Yagi, warning that gales will batter the Taiwan Strait, the South China Sea, the Bashi Channel, the coastal area of Fujian and the east coastal areas of Guangdong from Tuesday night to Wednesday night.

In the meantime, heavy rainfall is expected to hit the southern parts of Taiwan Island, according to the NMC.

China has a four-tier, color-coded weather warning system, with red representing the most severe warning, followed by orange, yellow and blue.