(Source：Hong Kong Observatory)
Rains and tropical cyclones can lead to floods in Hong Kong.
Hong Kong receives the most rainfall during summer. Our Amber, Red and Black Rainstorm Warning Signals alert the public of heavy rain exceeding 30, 50 and 70 mm respectively within the hour, and that the rain is likely to continue . When the rate of rainfall exceeds the speed of water draining away, water accumulates and results in floods .
Meanwhile, frequent tropical cyclones may lead to storm surge , which may bring floods to low-lying areas. Depending on where the tropical cyclones land, they affect various coastal regions of Hong Kong. For example, Usagi in 2013 caused a landfall near the east-northeast of Hong Kong, resulting in floods in northern and western New Territories (Lau Fau Shan, Tuen Mun and Tai Po) and Sham Shui Po . Cyclone Manghkut moved near south-southwest of Hong Kong  in 2018 and thus brought floods to Heng Fa Chuen, Tai O, Lei Yue Mun, Tseung Kwan O and part of the New Territories .
Floods can cause injuries, deaths and destroy property. To protect your family and yourself, you can refer to some tips to prepare for and respond to floods   .
- Make sure objects likely to be blown away (e.g. overhanging facilities and temporary structures outdoors) are securely fastened or taken indoors.
- The electricity supply of neon signs should be switched off.
- Adhesive tape should be fixed to large windowpanes in exposed positions to reduce damage and injury by broken glass.
- Drains should be cleared of leaves and rubbish.
- Prepare a torch, dry cells, radio and candles in case of power shortage.
- If you are planning an outing, remember that the typhoon may affect your trip.
- Stay away from the shoreline and do not to engage in water sports.
- Listen to the radio, watch TV or browse the Observatory's website and mobile apps for the latest information.
- People in low-lying areas should take precautions against flooding.
- Small vessels should seek shelter without delay.
- If you are outdoors, you should find a safe place now and remain there until the danger is over. If you are reasonably protected indoors, stay where you are.
- Avoid going to low-lying areas, which are likely to be affected by serious flooding under a storm surge.
- Lock all windows and doors; park your car in a safe place.
- Stay away from exposed windows and doors because glass will shatter easily under strain from wind pressure. You should only fix broken windows and doors when there is no danger in doing so.
- Do not touch electric cables that have been blown loose.
- Listen to authorities for information and special instructions.
- Avoid damaged neon signs, road signs or trees.
- Do not touch electrical equipment if it is wet or if you are standing in water. If it is safe to do so, turn off electricity at the main breaker or fuse box to prevent any electric shock.
- Document any property damage with photographs and contact your insurance company for assistance.