Hong Kong raised its highest typhoon warning early Wednesday as it braced for Typhoon Ragasa, the most powerful storm in the world so far this year, prompting forecasters to warn that sea levels could rise significantly. The center of the typhoon had passed the south of Taiwan on Tuesday, killing 14 people and leaving dozens missing. In Hong Kong, in Shenzhen and elsewhere in southern China, residents stocked up on supplies as they prepared for the storm to reach them. The dead and unaccounted for came from one part of Hualien County, in the east, the agency said, and almost 8,000 people were evacuated across Taiwan. After making landfall in the northern Philippines on Monday, Ragasa headed back out to sea and barreled toward southern China on Tuesday, prompting the cancellation of hundreds of flights, mass evacuations and the closure of Hong Kong’s Disneyland and Macau’s casinos.