Chinese forecasters issued a typhoon red warning at 6am.

China’s national meteorological centre said Saola, currently located about 315km southeast of Guangdong province, will move northwest across the South China Sea at a speed of about 10kph, gradually approaching the coast of Guangdong, then slowly weaken in intensity.

Wind speeds at noon were clocked at 209kph.

Saola will make landfall along the coast somewhere from Huilai County in Guangdong to Hong Kong on the afternoon to the night of Sept 1, the centre said, adding with its forecasted intensity, it could be among the five strongest typhoons to land in Guangdong since 1949.

As Saola approaches, Guangdong’s Shenzhen city said it would upgrade the typhoon warning level to yellow – the second lowest – at 6pm today, and suspend classes at nurseries, kindergartens, primary and secondary schools.

China Southern Power Grid said it is stepping up inspection of equipment and strengthening measures to prevent water leakage in basement power rooms.

China Railway has suspended several major train lines and Shanghai halted trains heading to Guangdong, according to local media.

The Hong Kong Observatory said it will raise its strong wind Signal to No 3 – the second lowest – later today.

Saola will also bring storm surges to coastal low-lying areas, the observatory noted, estimating Saola is currently about 440km from the metropolis.

Until 8am tomorrow there will be heavy rainfall in parts of Fujian and areas of Guangdong.

Downpours could be 100mm to 220mm in some areas.

Saola’s winds are also affecting Fujian province, where videos on social media showed waves crashing along the coastline.

The meteorological administration of Shishi city issued a typhoon blue warning.