What is the level of the blue sandstorm warning? Is the blue sandstorm warning serious?

1. Blue warning: Sandstorms with visibility less than 1,000 meters are expected to occur in most areas of two or more provinces (autonomous regions and municipalities) in the next 24 hours; or have already occurred and may continue, it represents IV class.

2. Meteorological disaster early warning signals are generally divided into four levels: blue, yellow, orange, and red, which respectively represent general (level IV), severe (level III), severe (level II) and special Severe (Grade I). At the same time, it has Chinese and English signs, which are consistent with all emergency response levels and colors of the country. The blue sandstorm forecast signal specifically represents that sandstorm weather may occur within 24 hours (visibility less than 1,500 meters) or that sandstorm weather has already occurred and may continue. The yellow sandstorm warning signal specifically means that a sandstorm may occur within 12 hours (visibility less than 1,000 meters) or a sandstorm has already occurred and may continue. The orange sandstorm warning signal specifically means that strong sandstorm weather (visibility less than 500 meters) may occur within 6 hours, or that strong sandstorm weather has already occurred and may continue. The sandstorm red warning signal specifically means that extremely strong sandstorm weather (visibility less than 50 meters) may occur within 6 hours, or extremely strong sandstorm weather has already occurred and may continue.