Typhoon Kompasu is unlikely to hit Shanghai but will probably make its impact felt on the city Wednesday with severe rain and gales, the Shanghai Meteorological Bureau said on Tuesday.

Classes are suspended today in Shanghai's schools and kindergartens - delaying the start of the new school year. International and vocational schools and construction sites also have called off work out of concern for safety.

With a speed of 30 kilometers per hour, Kompasu arrived in the south of the East China Sea at 8pm on August 31, and was expected to come closest to Shanghai at noon today. The storm's effects should intensify this morning and peak in the afternoon, according to Shanghai Meteorological Bureau.

Torrential rain is likely to sweep across the city with heavy winds, the bureau said.

The wind speed in urban areas and the Expo site could reach 49 to 74 kilometers per hour and could even rise to 102 to 133 kilometers per hour in the city's coastal areas, the bureau said.

Weather, flood-control and other authorities were working together last night to prepare the city for the expected winds and rain.

"It could be intensified as a severe typhoon," said Dai Jianhua, a chief weatherman of the bureau. "But it is likely to go northeast and should not make a landfall in the city."

The bureau issued a blue typhoon alert, lightest of the four-level system, at 5pm on August 31.

About 300 workers of the Pinghu Oilfield on the East China Sea were evacuated, with the last group back on shore on August 31, authorities said.

Li Kaixi, a Sinopec official, said that the last batch of workers, nearly 90 people, left the oilfield on Monday by ship and arrived in the Pudong New Area after a 25-hour voyage.

Ships near the city's ports were all asked to anchor by Tuesday.

The Expo bureau said it was monitoring for potential floods and all pumps had been prepared to handle the coming storm.

Shanghai airport authority urged passengers to pay more attention to their flights today, saying it is likely that cyclone would affect the airports in Shanghai and Zhejiang, Fujian and Guangdong provinces.