BEIJING, Aug. 1 (Xinhua) -- China's national observatory issued a blue alert for Typhoon Sinlaku Saturday, which is expected to bring gales and torrential rains to south China.
The typhoon, the third of the year, has strengthened from a tropical depression Saturday afternoon and swept the coastal waters south of the city of Sanya, south China's Hainan Province, before heading to the Beibu Gulf, the National Meteorological Center (NMC) said.
The center expected the typhoon to continue to move northwestward at a speed of 15 km per hour and make landfall on the northern coast of Vietnam Sunday afternoon, where it will start to weaken.
Meanwhile, the center warned that another tropical depression, currently southeast of the eastern Zhejiang Province, is likely to move northwest at a speed of 20 km per hour and strengthen into the fourth typhoon of the year in the next 24 hours.
The fourth typhoon is expected to land on the coastal areas of Zhejiang and Fujian Monday night and quickly weaken thereafter, said the NMC.
From Saturday evening to Sunday evening, gales are expected to hit the Qiongzhou Strait, the Beibu Gulf, parts of the East China Sea and the South China Sea, as well as some sea areas near Taiwan, the Xisha Islands, Hainan, Guangdong and Guangxi.
In the same period, the Xisha Islands and parts of Hainan, Guangdong and Guangxi will experience heavy rains, with some areas to see downpours of up to 150 mm of rainfall, according to the NMC.
The Ministry of Emergency Management, having arranged disaster-relief works for Typhoon Sinlaku, said the rainstorms in south China could continue till next Thursday and impact other parts of the country.
The ministry urged local authorities to pay high attention to flood and typhoon prevention works, strengthen the monitoring and early-warning systems, prepare for the relocation of disaster-hit residents and comb out safety loopholes to safeguard the lives of people.
China has a four-tier color-coded weather warning system for severe weather, with red representing the most severe, followed by orange, yellow and blue.