Beijingers woke Friday to see a yellowish-grey sky that heralded the year's first apparent sandstorm, as winds that had whipped up dust in China's arid northwest Thursday hit parts of the city.

The municipal weather bureau said a cold current hitting northern China had swept dust into the capital, and the dust weather worsened Friday afternoon when wind speeds rose to 40 km per hour.

But the sandstorm was not expected to last long, and the bureau forecast sunny weather for Saturday.

Shijingshan District in western Beijing and Changping district on the northern outskirts suffered the most from the storm, the bureau said on its website.

Beijing's environmental protection bureau said several of its downtown surveillance stations had detected higher than normal levels of particulate matter -- a major indicator of air pollution, at an average 500 mg per cubic meter.

In the outer Changping and Daxing districts, the level topped 800 mg per cubic meter, it said.

Sandstorms were reported in many parts of China starting Thursday.

Golmud City in the Qaidam Basin of the northwestern Qinghai Province reported the strongest winds in 30 years, with gales of 95 km per hour.

The sandstorm reduced visibility to 10 meters in the early hours of Thursday, said Zhang Jinong, a weatherman with the provincial meteorological bureau.

A sandstorm and temperature drops were also reported in Ningxia Hui Autonomous Region.

In the Inner Mongolia Autonomous Region, one of the traditional sources of Beijing's sandstorms, gales roared Thursday and Friday, and men and women wrapped themselves in scarves and wore masks.

The regional weather bureau said the sandstorm would ease Friday night, but with a new cold current during the day, most parts of Inner Mongolia would experience a temperature drop of 6 to 8 degrees Celsius.

The northeastern parts of the region should expect light snow Friday night and Saturday, it said.