Weather forecasters are warning of disruption to transport and other problems with the sandstorm season beginning two months earlier in southwest China's Tibet Autonomous Region.

Lhasa, the regional capital, was cloaked in dust on Sunday afternoon. Winds gusting up to 79 kilometers per hour swept up debris and even blew over a ten-meter tree.

Flights were cancelled or postponed, leaving about 400 passengers stranded in the airport.

"Dust storms hit Lhasa every year, but normally not until March," said Zhoema, who has been living in the city for over 30 years. "It is rare to see such a strong dust storm in January."

Experts said the sand mainly came from the Lhasa River to the south of the city. They believed that this winter's very low rainfall, only 0.1 mm, and high temperatures were to blame for the weather.

The weather in Lhasa improved on Tuesday, but experts did not rule out the possibility of more dust storms with more high winds expected on Wednesday.

The first dust storm of the year hit Lhasa on Jan.10, according to the regional meteorological station.

A daytime temperature of 20.4 degrees Celsius was recorded in Lhasa at the beginning of this month, just a tenth of a degree below the record high set in 2001, said Yu Zhongshui from the meteorological station.

Lhasa is one of the Chinese cities that has the best air quality, reporting 363 days of good air quality from December 2005 to October 2006.

Editor: Donald