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.

Heavy rains in Taiwan brought severe flooding and the collapse of a bridge, the island’s emergency department said at a news conference Tuesday evening, and floodwaters stranded people at home or on car rooftops. 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.

China’s National Meteorological Center forecast that the storm would make a second landfall on Wednesday near Shenzhen, a tech hub that borders Hong Kong. Shenzhen’s government said it would evacuate 400,000 people and close the airport at 8 p.m. on Tuesday.

Ragasa briefly reached sustained wind speeds of 165 miles per hour on Monday, according to the Joint Typhoon Warning Center. It has since been downgraded to a Category 4 storm.

Experts say that typhoons are increasing in the region, and officials are bracing for Ragasa to be one of the worst in years.

The Hong Kong Observatory raised its highest storm signal, level 10, at 2:40 a.m. on Wednesday. The forecaster said that rain could fall at a rate of more than an inch per hour and that sea waters could reach 13 to 16 feet above normal by the afternoon. It urged residents not to go outside.

On Tuesday, crowds had gathered by coastlines in Hong Kong to watch the crashing waves. Among the spectators, a child and his mother had gotten swept into the sea and were rushed to intensive care after being rescued, according to the police.

Hong Kong Observatory’s forecasters warned that it could cause damage comparable to that of Typhoon Mangkhut in 2018, when ferocious winds shattered hundreds of glass windows in the city’s skyscrapers. Eric Chan, Hong Kong’s No. 2 official, described the typhoon as a “serious threat” to the city.

The city’s Disneyland resort was closed, horse races were canceled, classes were suspended and office workers went home early. Supermarket shelves were emptied as residents stocked up on food and many taped their windows at home. Maintenance workers set up flood barriers, covered outdoor escalators and secured sculptures to the ground.

At least 600 flights from Cathay Pacific, Hong Kong Airlines and other carriers have been canceled at Hong Kong International Airport. The airport said that its runways would continue to operate and that some restaurants and shops would stay open for 24 hours for stranded passengers. The airport authority said that it handled 600 flights on Tuesday, and that there were no passengers remaining in restricted areas. In Taiwan, 270 flights were canceled.

The gambling hub of Macau announced that casinos would be temporarily closed starting from Tuesday evening.

After hitting China, the storm is expected to continue westward, reaching as far as Vietnam and Laos later this week.

In the Philippines, the state weather bureau said Monday that the storm had caused heavy rains and landslides in areas in the north, many of which were still struggling with flooding from previous storms.

Amy Chang Chien contributed reporting from Taipei.