What does the blue warning of snowfall in Urumqi mean today?

Blizzard warning signals are divided into four levels, which are represented by blue, yellow, orange and red respectively. Divided into 4 grades according to the grade; I, II, III and IV, where each level corresponds to different colors and different degrees.

Meaning of blue warning: within 12 hours, the snowfall will reach more than 4 mm, or it has reached more than 4 mm and the snowfall continues, which may have an impact on traffic or agriculture and animal husbandry.