Strange weather that has seen cold fronts follow warm spells and fog shroud Shanghai, together with the approaching "super moon," are not portents of doom, scientists say.

This follows Internet claims that the "super moon" - which on Saturday will be 356,577 kilometers from the Earth, its closest in 18 years - caused the devastating earthquake that hit Japan last Friday.

But local astronomers have sought to reassure the public that there is no basis for these rumors.

"Many natural disasters also happen on the Earth when there is no so-called 'super moon,'" said Bian Yulin, deputy director of Shanghai Astronomical Society.

"It is always extremely likely that two incidents unrelated to each other happen at the same time."

Astronomers advise Shanghai residents to enjoy watching the "bigger" moon on Saturday night and rest assured that it will not bring chaos to the city.

In the meantime, spring may be on its way, but winter's reluctant to relinquish its grip on the city, with another cold snap on the way.

Temperatures will drop by 7 to 9 degrees Celsius over today and tomorrow and bring rain today, weather forecasters said yesterday.

Today's high temperature will be 14 degrees, down from yesterday's 18.1 degrees. It will fall further to around 10 degrees tomorrow.

The minimum temperature will fall to 4 to 8 degrees, said the Shanghai Meteorological Bureau.

The cold wave will disperse fog that troubled the city over the weekend. Yesterday morning, visibility was less than 1,000 meters, causing ferries to Chongming Island to be suspended until the afternoon.

Meanwhile, the China Meteorological Administration said yesterday that a cold front will sweep in from the west across many parts of the country over the next three days, bringing rain and sandstorms.

Sandstorms hit northwestern Xinjiang Uygur Autonomous Region and the western part of Inner Mongolia Autonomous Region early yesterday, Xinhua news agency reported.

Most of the sand would not reach Beijing, but some areas of the capital would see some particles carried by force four to five winds, according to experts with the Beijing Municipal Meteorological Observatory.

Meng Xuefeng, senior engineer with the Inner Mongolia Meteorological Station, told Xinhua that this cold front would bring a temperature plunge of up to 16 degrees and the first sandstorm of spring.

In Shanghai, from Wednesday the city will start warming up again. Temperatures will rise gradually to about 16 degrees on Friday, said the Shanghai Meteorological Bureau.