SHANGHAI - Almost 100 flights were delayed and 20 were canceled over Monday night and early Tuesday at fog-covered Shanghai's Pudong airport.

More than 30 incoming flights destined for Shanghai Pudong International Airport landed at Shanghai Hongqiao International Airport between 8 pm Monday and 8 am Tuesday.

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The heavy fog has covered the city since late Monday, reducing the visibility to less than 100 meters on Tuesday morning, said the Pudong airport spokesman.

An emergency response plan had been activated by the airport to cope with an influx of flights when the skies cleared, said the spokesman.

The airport reminded passengers to check the flight schedules.

Fog was expected to hit most parts of east China on Tuesday, with the visibility of less than 200 meters in parts of Beijing and Tianjin, said a warning issued by the National Meteorological Center Monday night.

Snow and strong winds are expected to hit north China's Inner Mongolia Autonomous Region in the next few days, reducing temperatures by up to 12 degrees Celsius, according to the provincial meteorological center.