Snowstorms are forecast for China's central and eastern regions, disrupting travel plans for millions seeking to return to work after family reunions during the Spring Festival holiday. China's meteorological authority on Wednesday issued a yellow alert for blizzards that will sweep through Shaanxi, Shanxi, Henan, Shandong, Anhui, Jiangsu and Hubei provinces from Wednesday afternoon to Thursday afternoon. China's meteorological disaster alerts are categorized as blue, yellow, orange and red, with red being the most severe and blue the least. Snow on the ground in some regions could be as thick as 16 cm, leading to icy roads, the National Meteorological Center said. Snowstorms could linger until Friday in some eastern and central regions, the center said in a statement. The blizzard follows a cold front that has hit the regions and brought temperatures down by as much as 18 degrees Celsius. All highways in four major cities in northern Hebei province and most highways in central Henan province have been closed as icy and slippery roads pose safety risks. The week-long Spring Festival, the most important traditional holiday in China, will end on Thursday and tens of millions of people will return to work from their hometowns.