Frequently Asked Questions
What is a Flood Watch?
Flood Watch is provided by the Bureau of Meteorology to notify the Queensland community to the possibility of riverine flooding. A Flood Watch essentially provides early advice of a developing situation that may lead to flooding.
Why is Flood Watch being introduced by the Bureau of Meteorology?
A Flood Watch will allow Queenslanders to better prepare for flooding. Research has shown that even the smallest of actions, taken early, can reduce the impact of flooding if it occurs. Flood Watch is an extension of the Bureau's riverine flood warning service in Queensland, and brings Queensland into line with the rest of Australia, where Flood Watch is already in place.
What information is in a Flood Watch?
Flood Watches will contain short general statements about the developing weather situation, including forecast rainfall totals. Catchments at risk of flooding will be listed. Links to weather warnings and other flood-related products will also be provided. Flood Watches will also contain links to emergency information and contact numbers.
Who issues Flood Watches in Queensland?
The Bureau of Meteorology’s Flood Forecasting & Warning team is responsible for issuing Flood Watches in Queensland.
Why are there two Flood Watch products for Queensland?
It is possible that two separate rainfall systems are forecast to affect Queensland, either in different parts of the state or several days apart. In this case, separate Flood Watches will be issued. For example, there may be a Tropical Cyclone in the Gulf of Carpentaria that poses a flood threat to the Gulf Rivers catchments, whilst another weather system is bringing the risk of flooding to south east Queensland.
Receiving Flood Watches
When did the Flood Watch service go live in Queensland?
The Flood Watch service went live in Queensland on Wednesday 15 October 2014.
The Flood Watch service went live on the 15 October 2014 but I can't see any Flood Watches anywhere – why not?
Flood Watches are only issued when forecast rainfall totals suggest that flooding above the minor flood level is possible at river level forecast locations. The absence of a Flood Watch means that there is currently no threat of riverine flooding within catchments and at locations where a formal flood warning service is provided.
How do I receive Flood Watches for Queensland?
Flood Watches will be provided to emergency services, local government and the media, in exactly the same way as Flood Warnings are currently provided. Flood Watches are also available directly from the Bureau of Meteorology, either via our website (www.bom.gov.au/qld/warnings) or through our Telephone Weather Service (1300 659 219)
Do I need to sign up or register for the Flood Watch service?
No, In Queensland Flood Watches are freely available via the Bureau’s website (www.bom.gov.au/qld/warnings) or through our Telephone Weather Service (1300 659 219). If you already receive Flood Warnings from the Bureau then you will automatically receive Flood Watches when these are issued for your area of interest.
How will I know if a Flood Watch applies to me?
When a Flood Watch has been issued it will clearly state the catchment(s) at risk of flooding. A map of the catchments in Queensland can be found at: http://www.bom.gov.au/qld/flood/brochures/qld/Qld_Basins_map.pdf. Once you know the catchment that you live or work in, you can identify whether the Flood Watch applies to you. Stay aware of subsequent updates to the Flood Watch, as the catchments at risk of flooding may change as updated forecast rainfall information becomes available closer to the event.
What geographic areas are Flood Watches issued for?
Flood Watches are issued for specific catchments (e.g. Fitzroy River) or groups of catchments (e.g. Gulf Rivers).
Does the Flood Watch cover the whole of Queensland?
Flood Watches are issued for catchments where the Bureau of Meteorology currently provides a flood warning service, so not everywhere across Queensland will benefit from this service. The Bureau plan to assess the feasibility of expanding the flood watch into those parts of Queensland that do not currently receive a flood warning service in time.
Why do Flood Watches generally cover such large areas?
Flood Watches are issued on the basis of forecast rainfall up to 4 days ahead of possible flooding and as such there will always be uncertainty associated with the location and amount of rainfall. Ahead of significant rainfall events it is often not possible to accurately predict rainfall on a small scale, so Flood Watches are deliberately targeted at relatively large areas to encompass the uncertainty in the geographical extent that is likely to be affected.
Timing of Flood Watches
It's not even raining – why has a Flood Watch been issued?
Flood Watch is provided by the Bureau of Meteorology to notify the Queensland community to the possibility of riverine flooding. Flood Watches will use forecast rainfall, which means they will be issued ahead of the rainfall in most situations. The Flood Watch will contain information on when the rainfall is expected to begin, rainfall totals and how long it will last.
How far ahead of rainfall events will a Flood Watch be issued for Queensland?
Flood Watches may be issued up to 96 hours ahead of flooding that may develop. However, given the inherent uncertainties of forecasting rainfall in Queensland, it is more likely that Flood Watches will be issued between 12 and 48 hours ahead of possible flooding when we have higher confidence in the rainfall forecast.
How frequently are Flood Watches issued and updated?
A Flood Watch will be issued when the forecast rainfall totals suggest that riverine flooding is possible within the next few days. The Flood Watch will then be routinely updated at least once a day, usually by mid-morning. However, if the rainfall forecast changes significantly between routine updates then the Flood Watch will be updated accordingly to ensure the information within it always remains current.
Is the Flood Watch service only operational during the wet season?
No, it is a year-round service. Flood Watches will be issued whenever forecast rainfall totals suggest that riverine flooding is possible.
Link with other flood and weather products
What is the key difference between a Flood Watch and a Flood Warning?
A Flood Watch is issued when forecast rainfall information suggests that riverine flooding is possible, whereas a Flood Warning is issued when the Bureau is more certain that flooding is expected, often when rainfall has started to fall. A Flood Watch may cover a large area due to uncertainty associated with the location and amount of forecast rainfall. Flood Warnings are more targeted and are issued for specific catchments or even sub-catchments in some of the larger river basins. Flood Warnings will generally include specific predictions of the severity of expected flooding.
Is it possible for a catchment to have both a Flood Watch and Flood Warning in place at the same time?
No. Given that a Flood Watch indicates that flooding is possible and a Flood Warning states that flooding is expected, the two cannot co-exist. Flood Watches are catchment-based, so if a Flood Warning is issued for a catchment the whole catchment will be removed from the Flood Watch and information about the catchment will now be communicated in the Flood Warning product. The Flood Watch may still remain in place for other catchments.
A Flood Warning was issued but there was no Flood Watch issued prior to this – why not?
There will be occasions when a Flood Warning is issued without it being preceded by a Flood Watch, largely due to the complexities of forecasting rainfall accurately in Queensland. Weather models are excellent at identifying broader scale weather patterns but are not always able to represent the smaller scale features that can cause heavy rainfall, particularly in the tropics. For this reason there will be times when heavy rainfall leading to flooding occurs but forecast models were not able to accurately identify this beforehand.
Will preliminary Flood Warnings and Coastal Rivers Flood Warnings continue to be issued in Queensland?
No, these two products will be replaced by Flood Watches.
How does a Flood Watch differ from a Tropical Cyclone Watch?
A Tropical Cyclone Watch is issued for coastal communities when the onset of gales associated with a Tropical Cyclone is expected in the next 24-48 hours, whereas, a Flood Watch is issued when forecast rainfall totals suggest that riverine flooding is possible. Essentially, the trigger for a Tropical Cyclone Watch is wind-related, whereas the trigger for a Flood Watch is flood-related.
Would a Tropical Cyclone Watch and Flood Watch be issued at the same time in Queensland?
Tropical Cyclone Watches and Flood Watches are issued independently of each other. It is possible that a Flood Watch may precede a Tropical Cyclone Watch if there is sufficient confidence in the rainfall forecast. Conversely, a Flood Watch may be issued around the same time as a Tropical Cyclone Watch or even after it. It is also possible that for some tropical cyclones only one or indeed neither of the products are issued if there is no wind threat or flood threat to land-based communities.
A Flood Watch has been issued for my area – does this mean that I will be flooded?
A Flood Watch provides early advice that riverine flooding is possible, not that flooding is expected. If the likelihood of flooding increases, or there is an imminent threat of floods occurring, a Flood Warning will be issued. When a Flood Watch is issued, it is an opportunity to take even the smallest of actions. For example, you could think about what you would do if flooding did occur or revisit any emergency plan that you may have.
Why is there no indication of the expected severity of flooding within a Flood Watch?
Two reasons: (1) The main objective of a Flood Watch is to provide early advice of possible flooding from a developing rainfall situation, not the severity of the flooding, and (2) At the lead time that Flood Watches are issued there is often too much uncertainty in the forecast rainfall to accurately predict the severity of flooding.
Are there any plans for a graphical-based Flood Watch product?
The Bureau will investigate this as part of a national project to improve the visibility of flood warning services.
What action should the public take if a Flood Watch is issued?
The public is encouraged to stay aware of subsequent updates to the Flood Watch and heed Flood Warnings if these are issued, and to follow the advice of their local emergency services. Consider making preparations to move livestock, family and possessions to higher ground if flooding develops. The Bureau’s website provides information about the latest rainfall and river level heights, as well as the latest weather forecast and warning information. It is advisable for the public to familiarise themselves with the Bureau’s website prior to floods occurring so that they know where key information can be found.
Why do the forecast rainfall totals stated in a Flood Watch often cover a large range (e.g. 200-300mm)?
At the lead time that Flood Watches are issued prior to actual rainfall or possible floods ocurring there is always a degree of uncertainty in the forecast rainfall totals. Expressing the expected rainfall as a range is a way to convey this uncertainty. Rainfall will also vary throughout the area covered by the Flood Watch, another reason why a rainfall range is stated.
Are Flood Watches issued for localised flash flooding?
Whilst Flood Watches are not issued specifically for localised flash flooding, if heavy rainfall conducive to flash flooding is likely then this will be mentioned in the Flood Watch. Heavy rainfall that may cause flash flooding is also mentioned in severe weather and thunderstorm warnings issued by the Bureau of Meteorology.
What does it mean if a Flood Watch is cancelled?
There is always some uncertainty associated with the rainfall forecast. If the weather situation does not develop as initially indicated by weather models and it becomes clear that there is no longer a risk of flooding the Flood Watch will be cancelled to signify this.
How is flooding defined?
The Bureau of Meteorology defines flooding to occur when the minor flood level is exceeded at river level forecast location.
Download the Queensland Flood Watch Brochure
Further information about the Queensland Flood Watch service can be obtained from the Flood Forecasting and Warning team based in the Queensland office
More information about the Bureau’s flood warning service can be found at: www.bom.gov.au/water/floods/floodWarningServices.shtml