China's maritime authorities on Sunday continued to issue red alerts, the highest level of warning for storm tides and waves, as super typhoon Usagi is approaching land.

Photo taken on Sept. 22, 2013 shows the sky is covered with dark clouds as super typhoon Usagi approaches in south China's Hong Kong. More than 400 flights have been cancelled or delayed as super typhoon Usagi hit Hong Kong on Sunday. The Hong Kong Observatory issued a No. 8 storm signal, the third highest level, at 6:40 p.m. on Sunday, saying Usagi would make its landfall in the evening. [Photo/Xinhua]?

Usagi, the 19th typhoon to hit China this year, is expected to make landfall in south China's Guangdong Province on Sunday night, the National Marine Environmental Forecasting Center said.

Typhoon Usagi will bring waves as high as nine meters in the north of the South China Sea from Sunday night to Monday morning, with waves of up to six meters in the Taiwan Strait and sea area off eastern Guangdong. Usagi is expected to whip up peaks of 3 to 4.5 meters in Fujian Province's southern coastline and along Guangdong's western coastline.

The forecasting center also warned of storm tides, with water levels expected to increase by as much as 2 meters from Sunday afternoon to Monday afternoon.

Residents and tourists in affected areas are advised to stay away from beaches and litoral zones.

China has a four-tier, color-coded weather warning system, with red representing the most severe, followed by orange, yellow and blue.