Sun jun, chief forecaster of the National Meteorological Center, says the strong cold front is linked with the activity of the polar vortex.

　　"The cold wave is a severe cold air brought by a polar vortex. The polar vortex always hovers near the North Pole. But this time, influenced by a polar high-pressure system, it was pushed off the polar region."

　　The forecasts say that northern China will see a rapid rise in temperatures as much as 10 degree Celsius stating from today, and rarely-seen low temperatures in southern China will also fade out later this week.

　　The cold front over this past week has been labeled the strongest in decades, as it brought a sharp decrease in temperatures and strong precipitation.

　　本周迎来有史以来最强冷空气

　　In Beijing, the temperature dropped to minus 17 degrees Celsius on Saturday, the lowest recorded temperature in the capital in the last 30 years.

　　30 monitoring stations in and around the city recorded historical low temperatures.

　　In southern China, Wong Wai-Kin with the Hong Kong Observatory said the city recorded its lowest temperature of the last six decades.

　　"We have recorded 3.1 degrees Celsius in the afternoon at around 3:30, which is the lowest since the last low-temperature record in 1957."

　　Residents in downtown Guangzhou were excited to see sleet, the first in 60 years, on Sunday.

　　"I am a Cantonese but I have never seen such snow before. I am so excited, but the snowfall did not last very long."

　　"We could seldom experience such coldness in Guangzhou city. It is very rare to see these ice pellets in the rain, and the last time we saw them was over a decade ago."

　　With the cold front still lingering in southern China, doctors are warning citizens to take protective measures when going out.

　　The worst cold snap in years led to at least four deaths across the country.

　　For CRI, this is Niu Honglin.