BEIJING, Nov. 30 (Xinhua) -- China's weather observatory on Sunday issued a yellow alert for heavy snow that is to hit the country's northeast provinces.

　　The National Meteorological Center (NMC) forecasted that heavy snow will freeze Heilongjiang, Jilin and Liaoning provinces until Monday afternoon and some of the regions will see blizzards.

　　The NMC advised residents to stay indoors and asked local authorities to brace for the heavy snow.

　　China has a four-tier color-coded weather warning system, with red representing the most severe weather, followed by orange, yellow and blue.