One typhoon and two tropical storms are forecast to land or brush past East and South China coasts on Tuesday and Wednesday.

The converging forces will bring heavy rain to the region as they move further northwest.

Because of the storms, all high schools, primary schools and kindergartens in Shanghai suspended classes for Wednesday to ensure the safety of students, following a decision by the Shanghai municipal government on Tuesday night.

The storms also led to the evacuation of nearly 138,000 people in Fujian province and stranded hundreds of passengers in Zhejiang province after shipping services were cut on Monday.

The national meteorological center of the China Meteorological Administration (CMA) on Tuesday sounded an orange alarm - second in urgency to red - as the escalating tropical storms joined the typhoon to threaten the region.

"Three storms affecting Chinese costal areas at the same time is very rare," said Chen Zhenlin, director of the disaster relief and public service department of the CMA.

He added the typhoon and tropical storms developed in just 40 hours after the first one took shape on Sunday.

Chen also warned that more typhoons could hit China in autumn.

The storms were influencing one another, increasing the uncertainty of their directions of movement, strength and duration, which exacerbated difficulties for forecasting and defence, the CMA said in a report.

Vice-Premier Hui Liangyu called for enhanced weather monitoring and forecasting, for people to be evacuated from threatened areas and for ships to take shelter at ports.

Hui said special attention should be paid to secondary disasters, such as landslides being triggered by heavy downpours.

The coming tropical storms are Lionrock, the name of a hill in Hong Kong, and Namtheum, the name of a river in Laos. They are joined by Typhoon Kompasu, which means compass in Japanese.

Kompasu, moving northwest at a speed of up to 20 kilometers per hour, had already stranded 170 tourists, including six Russians, on Monday in Nanji Island of Zhejiang province, as its strong winds cut off ship services linking Nanji to the mainland, local police said.

Also in Zhejiang, more than 200 tourists and residents had been evacuated from Dachen Island of Taizhou city in case Kompasu paralyzes the navigation routes, Xinhua News Agency reported.

About 48,000 fishing ships in Fujian had safely returned to port by Tuesday afternoon, local media reported.