Hong Kong rainstorm warning signals
The rainstorm warning signals (Chinese: 暴雨警告信號) are a set of signals used in Hong Kong to alert the public about the occurrence of heavy rain which is likely to bring about major disruptions such as traffic congestion and floods. They also ensure a state of readiness within the essential services to deal with emergencies.[1]
Hong Kong Observatory is responsible for launching these signals and the signals are broadcast over radio and television.
Contents
The three-level system
AMBER rainstorm signal
This signal means:
Heavy rain has fallen or is expected to fall generally over Hong Kong, exceeding 30 millimeters in an hour, and is likely to continue.[1]
The AMBER signal gives alert about potential heavy rain that may develop into RED or BLACK signal situations. There will be flooding in some low-lying areas and poorly drained areas.
RED rainstorm signal
This signal means:
Heavy rain has fallen or is expected to fall generally over Hong Kong, exceeding 50 millimeters in an hour, and is likely to continue.[1]
The RED signal gives alert about potential heavy rain that may develop into BLACK signal situations. All students are to remain at school unless there is a visible risk to staying in the building. If still at home, all students are to stay at home until further notice. Listen to radios or check weather.
BLACK rainstorm signal
This signal means:
Very heavy rain has fallen or is expected to fall generally over Hong Kong, exceeding 70 millimeters in an hour, and is likely to continue.[1]
When the BLACK signal is issued, Hong Kong will come to a complete standstill. Schools will not dismiss students unless there is a visible risk to staying at school, and everyone is recommended to seek shelter immediately. Buses and other forms of public transport may be halted after a while to allow commuters to go home, depending on demand and the level of risk along the route. MTR services will be limited or suspended because of the risk of flooding.
The RED and BLACK signals warn the public of heavy rain which is likely to bring about serious road flooding and traffic congestion. They will trigger response actions by Government departments and major transport and utility operators. The public will be given clear advice on the appropriate actions to take.
History
In May 1992, Hong Kong Observatory has recorded 109.9 mm rainfall from 6 o'clock to 7 o'clock in the morning.[2] Later, HKO has proposed Hong Kong rainstorm warning signals which include four colours, green, amber, red and black.[3]
