Know your weather warnings

Learn about severe weather and the warnings that help you know it's on the way
Issued: 17 September 2024

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Warning you about severe weather

Severe weather can develop quickly and threaten lives and property. You can reduce its impact by getting ready before it happens. 

Our regular forecasts and warnings help you to stay aware of what's on the way. So which warnings can you expect to see for some of Australia's highest-impact weather?

We issue warnings when weather conditions have the potential to threaten lives and property. But different weather calls for different warnings. The information in warnings varies, as does how far in advance we issue them.

It's important to read warnings carefully to make sure you understand them and get the most out of them.

During any dangerous weather situation, follow the advice of your local emergency services.

How to access warnings

Image of a mobile phone screen showing warning notifications. Next to the image, text reads Weather warnings direct to your phone.

You can find the latest warnings on our current website or the BOM Weather app. One of the easiest ways to stay on top of them is to set up notifications on your app. That way you'll receive warnings for areas and weather types you choose, direct to your device.

Fire weather warnings

Weather has a big influence on fires. It can affect their size and intensity, how quickly they spread – and how dangerous they are to the community.

Fire risk is calculated by looking at weather and fuel conditions, such as how much vegetation there is to burn. It's communicated through fire danger ratings – moderate, high, extreme or catastrophic. We work with state and territory fire agencies, who set these ratings.

When the fire danger rating is extreme or catastrophic, we issue a Fire Weather Warning. The warning includes information about forecast weather conditions and advice from emergency services.

Fire weather warnings are issued:

  • early in the morning for the current day
  • in the afternoon for the following day.

Learn more about fire weather.

Scale of fire danger ratings in the Australian Fire Danger Rating System. The scale is shown in a semicircle. The semicircle is divided into 4 equal segments. From left to right: Moderate in green, High in yellow, Extreme in orange, Catastrophic in red.

Australian fire danger rating scale

Flood watches and warnings

Flooding is among Australia's most deadly natural disasters. But it's also important for the life cycles of many plants and animals, and for agriculture.

We issue warnings about riverine flood. This is where rivers break their banks and water covers the surrounding land. It's mostly caused by heavy rain, which can enter the river system a long way upstream. It can cover large areas and last for months in some regions.

We provide 2 kinds of flood advice – watches and warnings.

We issue a Flood Watch when forecast rain suggests that flood is possible. It provides early advice of a developing situation that may lead to flooding. It's not a warning of imminent flooding. 

A Flood Watch contains links to weather warnings, other flood-related information and contact details for emergency services. It can be issued up to 4 days in advance of expected flooding.

We issue a Flood Warning when we're more certain that flooding will happen at a particular location. Warnings include the expected severity of the flood and predictions about the level the river will rise to. If data isn't available to make specific predictions, the information is more general.

Learn more about flood.

Image of table titled 'Understanding flood advice'. The table text explains watches and warnings. A 'Watch' is issued when you should prepare. It covers a broad area of flood risk and provides early advice, 1–4 days before impact. A 'Warning' is when you need to take action. It advises a specific location of flood risk, indicates the risk level (minor, moderate or major flooding), and is issued 6 or more hours before impact.

Understanding flood watches and flood warnings

Severe thunderstorm warnings

While we experience many types of thunderstorms in Australia, some more intense ones are considered severe.

A thunderstorm is classified as severe if it produces any of the following:

  • large hail – 2 cm in diameter or larger
  • damaging wind gusts – 90 km/h or greater
  • tornadoes
  • heavy rain that may lead to flash flooding.

We issue a Severe Thunderstorm Warning when:

  • a severe thunderstorm is occurring, likely to occur or is reported
  • phenomena listed above are expected in the warning area
  • existing thunderstorms are likely to develop into a severe thunderstorm.

Severe thunderstorms can be quite localised and can develop, evolve and disappear quickly. The exact location can be hard to predict, even with short lead times.

There are 2 types of severe thunderstorm warning, detailed and regional. Both types show the warning area on a map.

Regional warnings cover broad areas and show where severe thunderstorms are or may be in the next 3 hours.

Detailed warnings also give time and location-specific information about the threat.

Learn more about severe thunderstorms.

Image with text that explains what make a thunderstorm 'severe'. We issue a Severe Thunderstorm Warning when a storm is producing or is expected to produce large hail of 2cm and larger, damaging winds with gusts of 90 km/h and stronger, heavy rainfall that may cause flash flooding, or tornadoes that may cause damage. The image shows icons representing these types of weather.

What makes a thunderstorm severe

Heatwave warnings

Severe and extreme heatwaves have claimed more lives than any other natural hazard in Australia.

We classify heatwaves by intensity – low, severe or extreme. We issue heatwave warnings when severe or extreme heatwaves are expected.

A heatwave warning consists of 4 maps covering 4 three-day periods, extending out to 3 days in the future. The warning includes:

  • expected maximum and minimum temperatures
  • when the heatwave will peak and/or ease
  • a list of affected towns and communities within the warning area
  • action statements agreed with health and emergency service agencies across Australia.

We issue the warnings at 3 pm in all states and territories except Western Australia, which receives theirs at 2 pm.

Learn more about heatwaves.

4 maps of Western Australia. Each shows a 3-day heatwave forecast. A legend shows white for no heatwave, yellow for low intensity, orange for severe and red for extreme. The first map from Friday 16/02/24 shows a widespread low-intensity heatwave with severe areas across the middle and north-west. From Saturday, an extreme heatwave is forecast for the Broome area. The remaining 2 maps show the extreme conditions continuing to develop, while further south severe conditions contract.

Example of heatwave warning maps

Tropical cyclone watches and warnings

Tropical cyclones are violent, spiralling wind and rain systems that threaten lives and property. They can cause disruption, damage and destruction far beyond the coast.

Alerting you about cyclones takes the form of watches and warnings, depending how long it is before the gales start to affect the coast:

  • when gales are expected to start within 24 to 48 hours, we issue a Tropical Cyclone Watch, updating it every 6 hours
  • when gales are expected within 24 hours or already happening, we issue a Tropical Cyclone Warning every 3 hours.

Both forms of advice contain a tropical cyclone forecast track map. The map shows:

  • forecast movement – a shaded area indicates where the cyclone centre may move
  • intensity
  • watch or warning zones.

Learn more about tropical cyclones.

Understanding cyclone advice. A 'Watch' is when damaging winds are expected within 48 hours. A 'Warning' is when damaging winds are expected within 24 hours or are already happening.

Understanding cyclone watches and warnings