Chinese state media report at least 121 passenger trains are suspending service in anticipation of the arrival of Typhoon Saola.
People in areas of southern China were warned to stay away from the coastline and several cities delayed the start of the school year.
The suspensions on key lines running from north to south as well as on regional networks will begin Thursday and continue through Sept. 6, state broadcaster CCTV reported.
China's National Meteorological Center said Saola was moving toward the coast at a speed of about 15 kph (9 mph) and was due to make landfall Friday afternoon in the southern province of Guangzhou with sustained winds of 119 kph (74 mph) and gusts of up to 220 kph (137 mph).
The storm will then travel west down the coast into the Guangxi region before curving south out to sea between Saturday night and Sunday morning, gradually weakening as it goes.
The Guangdong city of Shanwei, closest to where Saola is expected to make landfall, ordered a halt to classes, transport and most economic activity until the all-clear is sounded.
Other cities, including Shantou, Shanwei, Jieyang and Chaozhou, have ordered the start of the school year to be delayed until Monday. Regional airports have also suspended flights until the storm passes.
The weather center has already issued a red alert for potentially destructive winds and possible flooding, with some areas expected to receive up to 200 millimetres (8 inches) of rain.
Other typical safety precautions include recalling fishing boats to port and moving people who work on coastal fish and shrimp farms further inland, but no figures on evacuations were immediately released.
As the storm moved closer to Hong Kong, the city's leader, John Lee, said in a Facebook post that he had requested various government departments to plan ahead and urged residents to take precautionary measures.
The Hong Kong Observatory plans to issue a No. 8 typhoon signal, the third-highest warning under the city's weather system, for early Friday, and schools will be suspended that day, Chief Secretary Eric Chan said during a news conference.
The observatory warned of squally showers, strengthening winds and a possible storm surge in low-lying areas of the crowded financial centre.
It urged residents to avoid water sports and stay away from coastal areas.
Saola passed just south of Taiwan on Wednesday before turning to mainland China, with the storm's outer bands hitting the island's southern cities with heavy rain and strong winds.
The typhoon also lashed the Philippines earlier this week, without any reports of casualties so far.
However, in the northern part of the islands, low-lying villages were flooded and nearly 50,000 people displaced, including 35,000 villagers, who fled to government-run evacuation centres.
Seaports suspended inter-island ferry services due to rough seas, and more than a hundred houses were damaged.
Meanwhile, a second storm, Haikui, is brewing near Japan's Ryukyu islands and will develop into a typhoon as it moves toward the Chinese coast, where it is expected to make landfall south of Shanghai on Sunday morning with sustained winds of 165 kph (102 mph).
The storms follow some of the heaviest rains and deadliest flooding in years across a wide swath of China, with scores killed, including in outlying mountainous parts of the capital Beijing.
The US Embassy in Beijing and consulates across the country emailed citizens urging them to take precautions and avoid areas likely to be affected.
Damaging winds, heavy rains, potential flooding, mudslides, and difficult travel conditions including potential transportation disruptions in coastal areas and inland are expected in Southern and Eastern China, with severe weather forecasted from September 1 to September 4, the message said. (AP) FZH 08311633