 This system formed in the South China sea on August 9 , and moved northwest through Hainan Island into mainland China , dissipating on August 12 . In Hong Kong , winds gusted to 70 knots ( 130 km / h ) at Tate 's Cairn and Tai Mo Shan while Tai Po received 343 millimetres ( 13 @.@ 5 in ) of rainfall from the depression . Extensive flooding occurred on Hainan and western Guangdong Province , killing two people . The Hong Kong Royal Observatory considered this system a tropical depression . 
