If you live in a flood prone area, it’s important to know your risk and understand how severe a flood is likely to be.

Riverine floods typically occur 6 or more hours after heavy rainfall. In Australia, we have 3 riverine flood classifications: minor, moderate and major.

Minor flooding refers to inundation of low-lying areas next to watercourses. Minor roads may be closed and low-level bridges submerged. In urban areas inundation may affect some backyards and buildings below the floor level as well as bicycle and pedestrian paths.

For moderate flooding the area of inundation is more substantial. Main traffic routes may be covered and some buildings may be affected above floor level. Evacuation of flood affected areas and removal of stock may be required.

Finally, major flooding can be very dangerous and may result in extensive inundation of rural and urban areas. Properties and towns are likely to be isolated and major traffic routes and rail routes are likely to be closed. Evacuation of people from flood affected areas may be required and utility services may be impacted.

The Bureau produces warnings and advice to local communities who are experiencing, or are at risk of experiencing riverine flooding.

Flood Watches provide early advice of a developing situation that may lead to flooding. While Flood Warnings are issued when floods are likely to occur or are already occurring.

Sometimes short bursts of heavy rainfall can lead to rapid onset flooding, known as flash flooding. When this is likely to occur, the Bureau will issue a severe weather warning for heavy rain that may lead to flash flooding.

Current flood watches and warnings, as well as severe weather warnings can be found on our warnings page or the BOM weather app. You can also access rainfall and river level data for around 3,500 locations across Australia.

Sadly, fatalities are common around flood waters. Just 15 cm of water is enough to make your car float. So remember, the best way for you to stay safe is to stay out of flood water and follow advice from local emergency services.

Understanding flood classifications

This video will help improve your knowledge of flood classifications, as well as help you understand the difference between flood watches and warnings.

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