On April 25, 2004, a sandstorm appeared again in the ancient capital Beijing, which was the eighth sandstorm in that spring. Meteorologists said that sandstorms came the earliest this year.

Drought and lack of rain, warming weather and rising temperature in the early stage of North China are the special weather and climate background for the formation of sandstorms. The development of convective cells into clouds before the ground cold front is a small and medium-sized system that is conducive to the development and strengthening of sandstorms. The topographic condition conducive to the increase of wind speed, that is, the narrow tube effect, is one of the favorable conditions for the formation of sandstorms; Therefore, frequent sandstorms in Beijing are closely related to cold front activities.

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