Typhoon Saola threatens China with category 4 winds

China already under the highest level of alert under a four-tier typhoon warning system.

Typhoon Saola, a powerful tropical cyclone packing the force of a Category 4 hurricane, was moving west through the South China Sea on Thursday toward Hong Kong and the Chinese mainland.

Saola was about 254 miles east-southeast of Hong Kong on Thursday morning, the Chinese territory’s meteorological agency said in a warning, adding that the storm would produce high winds and “heavy squally showers” there starting Friday.

Hong Kong said that it planned to issue weather warnings later Thursday, and China was already under the highest level of alert under a four-tier typhoon warning system.

Saola was generating sustained winds of 155 mph on Thursday, according to the Joint Typhoon Warning Center, a meteorological service operated by the US Navy. That is 2 mph below a Category 5 storm on the five-tier wind scale that is used to measure tropical cyclones in the Atlantic.

The storm has been moving through the region for days. It prompted evacuations in the Philippines and some school closures and travel disruptions in Taiwan, but it has not been linked to any deaths or injuries.

Saola was one of three tropical systems swirling in the Northwest Pacific on Thursday. The others, Kirogi and Haikui, were swirling farther east, and far from land, as tropical storms.

Hurricanes and typhoons are tropical cyclones with sustained winds of at least 74 mph. The term “hurricane” refers to tropical cyclones in the Atlantic basin; “typhoon” refers to ones that develop in the northwestern Pacific and affect Asia.

Typhoon Saola is named for an elusive species of wild ox that is native to parts of Southeast Asia.

Forecasters say it is hard to say exactly where or if the storm will make landfall. That is partly because Tropical Storm Haikui might influence its trajectory. Saola could also be influenced by the annual summer monsoon.

The Philippine meteorological agency said that Saola would likely move parallel to the coast of the southern Chinese province of Guangdong on Saturday, and that a landfall in mainland China was possible on Sunday.

Either way, the agency said, the storm was expected to weaken as it moved through the South China Sea, becoming a tropical storm by Monday.