AlHijjah 10, 1433, Oct 26, 2012, SPA -- Son-Tinh, the 23th tropical storm to approach China this year, is expected to bring strong rainfall and gales in the southeast coastal region, the meteorological authority said Friday. China Meteorological Administration (CMA) said the center of Son-Tinh, which became a strong tropical storm on Friday morning, was 440 kilometers southeast of Sansha, a newly established city in the South China Sea. It was moving northwestward at a speed of 25 kilometers per hour, Xinhua reported. Impacted by Son-Tinh and a cold front from the north, the southern part of China, including Huangyan Island, Sansha, Hainan province, Leizhou Peninsula and southern Guangxi Zhuang Autonomous Region will be battered by downpours in the next 48 hours. Southern Hainan will be the hardest hit, CMA forecast said. Meanwhile, coastal areas of Guangdong, Guangxi and Hainan provinces will see strong gales, CMA added. Meteorological experts advised local authorities to call ships back to harbors and reinforce port facilities.