Severe weather and coastal hazard warning services

Learn about severe weather, coastal hazard and severe thunderstorm warnings – what's included and where to find safety information

On this page

Severe Weather Warnings

Coastal Hazard Warnings

Severe Thunderstorm Warnings

Staying safe in severe weather

Epidemic thunderstorm asthma

Severe Weather Warnings

Types of weather covered

We provide Severe Weather Warnings for potentially hazardous or dangerous weather that is not solely related to severe thunderstorms, tropical cyclones or bushfires.

Damaging winds

Severe Weather Warnings are issued for damaging winds, including:

• sustained gale force winds – 63 km/h or more
• damaging wind gusts – 90 km/h or more, except In Tasmania where they are issued for gusts of 80 km/h or more in easterlies and 100 km/h or more in westerlies.

Rain and blizzards

We also issue Severe Weather Warnings for:

• heavy rain that may lead to flash flooding
• blizzards in alpine areas.

When do we issue Severe Weather Warnings?

These warnings are issued whenever severe weather is:

• happening in an area, or
• is expected to develop or move into an area.

The lead time depends on the weather situation. It can extend from an hour to 36 hours.

What's included

A Severe Weather Warning includes:

• a list of all potential phenomena, forecast districts and locations that may be affected
• a description of the threat and the area likely to be affected (the threat area)
• the time the warning was issued and what time the next warning will be issued
• a description of the weather pattern, including forecast developments of significant weather systems
• a technical summary of all potential phenomena, their timing and likelihood
• confirmed observations and reports
• recommended actions.

Updates

While the threat remains, a Severe Weather Warning is updated routinely every 6 hours. More frequent warnings may be issued if required.

Limitations

Warning services may be more limited for remote and unpopulated areas, as data may not be available for effective monitoring and prediction.

Coastal Hazard Warnings

Types of weather covered

We provide Coastal Hazard Warnings for abnormally high tides or storm tides that:

• may be higher than the highest astronomical tide, and
• could flood low lying coastal areas.

We also issue these warnings for damaging surf. This is when unusually large surf may damage beaches and coastal infrastructure.

When do we issue Coastal Hazard Warnings?

These warnings are issued whenever a coastal hazard is:

• happening in an area, or
• is expected to develop or move into an area.

The lead time depends on the weather situation. It can extend from an hour to 36 hours.

What's included

A Coastal Hazard Warning includes:

• a list of all potential phenomena, coastal forecast districts and locations that may be affected
• a description of the threat and the area likely to be affected (the threat area)
• the time the warning was issued and what time the next warning will be issued
• a description of the weather pattern, including forecast developments of significant weather systems
• a technical summary of all potential phenomena, their timing and likelihood
• confirmed observations and reports
• recommended actions.

Updates

While the threat remains, a Coastal Hazard Warning is updated routinely every 6 hours. More frequent warnings may be issued if required.

Limitations

Warning services may be more limited for remote and unpopulated areas, as data may not be available for effective monitoring and prediction.

Severe Thunderstorm Warnings

Warning about thunderstorms

All thunderstorms are dangerous because they produce lightning.

In Australia, we don't warn about all thunderstorms – only those classified as severe or very dangerous.

Severe thunderstorms

Thunderstorms are classified as severe when they produce one or more of these phenomena:

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

Very dangerous thunderstorms

Thunderstorms are classified as 'very dangerous' when they produce one or more of these severe phenomena:

• giant hail – 5 cm in diameter or greater
• destructive winds gusts – 125 km/h or greater
• tornadoes
• intense rainfall that may lead to dangerous and life-threatening flash flooding.

To learn more about severe thunderstorms, view our Thunderstorms page.

When do we issue Severe Thunderstorm Warnings?

We issue a Severe Thunderstorm Warning when:

• a severe thunderstorm is occurring, likely to occur or is reported
• phenomena such as large hail, giant hail, damaging winds, heavy rainfall, intense rainfall or tornadoes 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 dissipate quickly. The exact location can be hard to predict, even with short lead times.

Types of Severe Thunderstorm Warnings

We provide two types of Severe Thunderstorm Warning:

• Detailed Severe Thunderstorm Warning
• Regional Severe Thunderstorm Warning.

Detailed Severe Thunderstorm Warnings

We issue these warnings for all capital cities and surrounding areas. They are issued when individual severe thunderstorms are within range of the capital city radars.

Detailed warnings provide time and location-specific information about the threat. The warning includes a map showing:

• any existing severe thunderstorms as a red ellipse
• the forecast direction of movement for up to 60 minutes, in red arrows
• the Immediate Threat Area, shaded with orange-hash.

Example of a detailed severe thunderstorm warning map

Regional Severe Thunderstorm Warnings

This type of warning is issued for all Australian states and mainland territories. They highlight broad areas where severe thunderstorms are occurring or may occur in the next 3 hours.

These warnings:

• are based on broad areas, such as our weather forecast districts
• include a map with the areas covered by the warning shaded in yellow.

Example of a regional severe thunderstorm warning map

What's in Severe Thunderstorm Warnings

Both types of Severe Thunderstorm Warning include:

• a list of all potential phenomena, warned forecast districts and locations which may be affected
• the time and date the warning was issued and what time the next warning will be issued
• a description of the weather pattern, sometimes including forecast developments of significant weather systems
• confirmed observations and reports
• recommended actions.

If appropriate, the warnings may ask media to use the Standard Emergency Warning Signal (SEWS) in Queensland, Victoria and Tasmania. This is only used for the most serious events, such as confirmed very dangerous thunderstorms.

Severe thunderstorms during other severe weather events

Severe thunderstorms can happen during a more widespread severe weather event. For example, a band of heavy rain or vigorous cold front.

We work out which warnings will best inform the public about the hazards. We take into account warnings already in place and may consult local emergency services agencies.

Staying safe in severe weather

Preparing for severe weather

• Check forecasts and warnings on this website or the BOM Weather app and listen to your local radio station for warnings and updates.
• Shelter and secure pets and animals.
• Check your yard or balcony and secure or store items that could blow around in strong winds – for example, garden furniture, trampolines.
• Park vehicles under solid shelter or cover with firmly tied tarpaulins or blankets.
• Secure all external doors and windows and draw curtains.
• Charge your mobile phone and other devices and unplug these before the severe weather arrives.
• Put valuables, medications and spare warm clothing in plastic bags with your emergency kit and keep it handy.

When a thunderstorm strikes

• Stay inside and shelter well clear of windows, doors and skylights.
• Don't use a phone landline, as the wiring can carry electrical charges from lightning. This can mean deadly electric shocks or deafening sound blasts.
• Avoid touching brick or concrete, or standing bare-footed on concrete or tiled floors.
• Continue to check this website or the BOM Weather app and listen to your local radio station for warnings and updates.

Don't:

• drive, walk, ride or swim through flood waters, or drive through water flowing over roads
• fly kites or model aeroplanes with control wires
• handle fishing rods, umbrellas, golf clubs or similar items
• go near metal poles, fences, clotheslines or other metal structures
• ride horses, bicycles or travel in open vehicles.

If caught outdoors

• Move to shelter immediately. There is no safe place outdoors during a thunderstorm.
• Seek shelter in a 'hard-top' (metal-bodied) vehicle or solid building. Avoid small open structures or fabric tents.
• Never shelter under small groups of (or single) trees.

On the water

If you're swimming or surfing, leave the water immediately.

If boating:

• go ashore to shelter as soon as possible
• make sure the mast and stays of a sailing boat are adequately 'grounded' to the water.

More information about severe weather safety

For safety information, visit your state or territory emergency services.

Audio warnings

To get the latest warnings by phone at any time, call 1300 659 210.

Epidemic thunderstorm asthma

The Bureau doesn't issue thunderstorm asthma warnings. Check with your state or territory health authority to find out how alerts are issued for your local area.

Epidemic thunderstorm asthma can happen during grass pollen season – October through December – in south-east Australia. It may be triggered by a unique combination of:

• high amounts of grass pollen in the air
• a certain type of thunderstorm.

You may be at increased risk if you have:

• current, past or undiagnosed asthma, and/or
• seasonal hay fever.

Resources – epidemic thunderstorm asthma

Better Health Channel for more about thunderstorm asthma, who is at risk and how to protect yourself.

Victorian Department of Health epidemic thunderstorm asthma program and risk forecasting system.

Healthdirect website or Asthma Australia for information about thunderstorm asthma symptoms, prevention and treatment.

Asthma first aid – Asthma Australia.

Pollen information

Canberra Pollen for pollen levels in the ACT.

Melbourne Pollen for pollen levels in Victoria.

Sydney Pollen for pollen levels in Sydney.

AusPollen Brisbane for pollen levels in Brisbane.

AirRater for pollen levels in Tasmania, Northern Territory and ACT.

Severe weather warnings

View the National warnings summary.

Service level specifications for Thunderstorms and Severe Weather

This document describes our publicly available thunderstorm and severe weather services and the additional services we provide to support emergency management.

Thunderstorms and Severe Weather Service Level Specification – Word Doc, 10.1 MB

Need an accessible version of this document? Contact us about your needs.