More rainstorms loom on the horizon for flood-ravaged Hainan province, as the National Meteorological Center (NMC) said Typhoon Megi is forecast to hit the South China Sea on Monday.

Vehicles wade through on waterlogged street in Haikou, capital of south China's Hainan Province, Oct. 17, 2010. The heavy rainfall in the city on Sunday caused severe waterlogging in some areas. [Xinhua]

The strongest typhoon to hit China this year, Typhoon Megi was heading for Northern Luzon in the Philippines at a speed of 20 kilometers per hour after turning into a super typhoon early on Sunday. It is expected to enter the South China Sea on Monday, the NMC said.

With winds near its center reaching more than 56 meters per second, the super typhoon could wreak havoc across the South China Sea over the next few days.

The NMC issued an orange alert, its second-highest storm level, for strong winds at 10 am on Sunday, warning vessels to return to port and urging local authorities to prepare for emergency conditions.

The provincial meteorological center in Hainan has issued red alerts, the highest level, for four cities and counties, including Haikou, while an orange alert was issued for six cities and counties, and the orange alert for Tunchang county was upgraded to red at 4 pm on Sunday.

A second round of heavy rain has been battering the island province, adding to the damage caused earlier this month by the worst flooding in almost half a century.

Devastating storms and surging water levels throughout the province have posed serious challenges for flood control authorities.

Wei Liucheng, Party secretary of Hainan, and Luo Baoming, the provincial governor, have given top priority to the safety of reservoirs and issued instructions for evacuating residents who live downstream from them.

Military forces are on standby in Hainan to carry out emergency evacuations and provide disaster relief.

Hainan's flood emergency level was twice raised on Saturday to level 2, the second highest level. Haikou, the provincial capital, reported 103 villages were flooded and 15,150 residents had been evacuated as of Saturday.

"Now that we have an effective early warning system, we are better prepared," said Wang Ling, a resident of Qionghai city. "The damage is less than earlier this month."

In Wanning city of southeast Hainan, the fresh downpours caused several villages to flood again and rice fields were submerged in water.

Wanning flood control department told China Daily that by Sunday 16,000 residents from 4,234 households had been evacuated from dangerous areas.

In Ding'an county, 40,000 mu (2,667 hectares) of crops were damaged and 10 villages flooded, affecting 2,082 people as of Sunday.

At Yingke village in Ding'an county, 1,000 residents were stranded by the deluge when roads flooded.