1, the rainstorm warning signal is divided into four levels, which are represented by blue, yellow, orange and red respectively. In Chinese mainland, the red rainstorm warning signal is the highest level, indicating that the rainfall in some areas has reached 100 mm in the past three hours, and the rainfall may continue; In the Hong Kong Special Administrative Region, there are three levels (yellow, red and black), and the black rainstorm warning signal is the highest level; The Macao Special Administrative Region only has rainstorm warning signals.

2. Blue warning standard:/kloc-within 0/2 hours, the rainfall will reach more than 50 mm, or it has reached more than 50 mm and the rainfall may continue.

3. Yellow warning standard: within 6 hours, the rainfall will reach more than 50 mm, or it has reached more than 50 mm and the rainfall may continue.

4. Orange warning standard: within 3 hours, the rainfall will reach more than 50 mm, or it has reached more than 50 mm and the rainfall may continue.

5. Red warning standard: within 3 hours, the rainfall will reach 100 mm or above, or it has reached 100 mm and the rainfall may continue.