Residents ride in rain in Zhengzhou, capital of central China's Henan Province, on Nov. 3, 2012. Temperature in Zhengzhou dropped some 10 degrees Celsius as a cold wind hit the the city and brought rainfall on Saturday. Local meteorological authorities issued a blue-coded alert of gale, the least serious level in China's four-color coded weather warning system after red, orange and yellow. (Xinhua/Zhu Xiang)

Municipal workers clear leaves on a road in Zhengzhou, capital of central China's Henan Province, on Nov. 3, 2012. Temperature in Zhengzhou dropped some 10 degrees Celsius as a cold wind hit the the city and brought rainfall on Saturday. Local meteorological authorities issued a blue-coded alert of gale, the least serious level in China's four-color coded weather warning system after red, orange and yellow. (Xinhua/Zhu Xiang)

Residents wearing warm clothes walk in Zhengzhou, capital of central China's Henan Province, on Nov. 3, 2012. Temperature in Zhengzhou dropped some 10 degrees Celsius as a cold wind hit the the city and brought rainfall on Saturday. Local meteorological authorities issued a blue-coded alert of gale, the least serious level in China's four-color coded weather warning system after red, orange and yellow. (Xinhua/Zhu Xiang)