Twin typhoons wreak havoc

Rammasun is due to pass very close to Shanghai by Friday

HONG KONG, China (CNN) -- A pair of fierce typhoons has wreaked havoc across the Pacific Ocean, leaving dozens feared dead in Micronesia and threatening to add to a worsening flood crisis in China.

The Micronesian atoll of Chuuk (Caroline Islands) made an appeal for international aid on Thursday after torrential rains from Typhoon Chata'an caused a series of deadly landslides.

At least 39 were killed or feared dead in more than 30 landslides since Monday in the Chuuk island group, which lies near Guam about 2815 km (1,750 miles) east of the Philippines.

Authorities are scrambling to search for survivors after almost 1,500 homes were damaged or destroyed by mudslides and five-foot (1.8 meter) floods unleashed by the typhoon.

Packing sustained winds of 120kmh, Cha'tam is forecast to intensify as it heads northwestwards towards the southern Marianas.

The eye of the typhoon is predicted to pass almost right over Guam bringing with it gusty to severe wins, torrential rain and flooding.

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Further west, the stronger of the two systems, Typhoon Rammasun, moved through the Ryuku Islands in western Japan overnight Wednesday, skirting around Okinawa, and is expected to move parallel to the eastern Chinese coast as it heads northwest.

The mammoth typhoon caused flooding, mudslides and at least one death in Okinawa. According to The Associated Press news agency, two U.S. Navy sailors were swept out to sea in high surf. One body was recovered while the other man is still reported as missing.

Though the intensity of the typhoon is weakening, Rammasun still has winds of 200kmh gusting to 290kmh and is causing a maximum swell of 36 feet (11 meters) as it lurks in the East China Sea, north of Taiwan.

Floods in China have already killed almost 800

The effects of Rammasun are expected to hit the eastern provinces of Fujian, Zhejiang and Jiangsu as the typhoon passes very near to Shanghai by Friday, before continuing toward the Yellow Sea by the weekend.

A typhoon warning was posted on Wednesday in Zhejiang with residents and authorities in the area and neighboring provinces bracing for more heavy rainfall.

Flooding killed almost 800 people last month in eastern and southern China, and Rammasun is predicted to add to the full force of the rainy season.

Many rivers and lakes are already perilously close to danger levels with the Yangtze river system most at risk.

State media reported last week that the province of Hunan's Dongting lake, which acts as a buffer to the Yangtze, was only one centimeter below its flood warning level.

With more thunderstorms and rain forecast in the region in the coming days, there are fears of major flooding around the Yangtze this season, similar to the devastating floods of 1998 that left 4,000 people dead.