What does the color signal of weather warning indicate from low to high?

The color signals of meteorological early warning are blue, yellow, orange and red from low to high.

This is stipulated in the Trial Measures for Issuing Early Warning Signals of Sudden Meteorological Disasters issued by China Meteorological Bureau on August 16, 2004. Each color represents a different degree of early warning, which is easy to distinguish. Early warning signals are composed of names, icons, standards and defense guidelines, which are divided into typhoon, rainstorm, blizzard, cold wave, gale, sandstorm, high temperature, drought, lightning, hail, frost, fog, haze, road icing and so on.