Powerful winds and rough seas lash a coastline as a typhoon approaches. Authorities in southern China have evacuated thousands of residents and suspended transport services ahead of Typhoon Noul's expected landfall.

Authorities have evacuated more than 20,000 people and suspended railway services in southern China as approaching Typhoon Noul threatens torrential rain and gale-force winds, according to state media.

The typhoon is forecast to make landfall in the coastal area stretching from Hong Kong to Guangdong province between Saturday evening and Sunday morning, China's National Meteorological Center said.

It maintained an orange typhoon alert on Saturday, the second-highest level in its four-tier system, after warning that parts of Guangdong and neighbouring Fujian province would experience gales and torrential rain.

More than 20,000 people had been evacuated in Guangdong, state broadcaster CCTV said in a bulletin late Friday.