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Heatwave services

Learn about our heatwave maps, warnings, forecasts and assessments.

On this page

About our heatwave service

Understanding heatwave maps

Heatwave warnings

Heatwave forecasts

Heatwave assessments

About our heatwave service

Our heatwave service includes:

  • warnings of any severe or extreme heatwave within the next 4 days
  • forecasts of heatwaves likely in the next 7 days.

Heatwave forecasts and warnings are generally issued from October until the end of March. Depending on conditions, the service may start earlier or run later.

We also provide assessments, which show the severity of a heatwave over the previous 2 three-day periods.

Our heatwave service aligns with the National Heatwave Warning Framework, an agreed approach to managing heatwaves across Australia.

Service level specification for heatwave

This document describes our publicly available heatwave services and the additional services we provide to support health and emergency management.

Video: Understanding heatwave warnings



View video transcript

Understanding heatwave maps

The maps use colours to show the 3 different heatwave intensities:

  • yellow indicates a low intensity heatwave
  • orange indicates a severe heatwave
  • red indicates an extreme heatwave.

In our heatwave forecasts and warnings, each map shows a 3-day period starting from that day.

For example, a heatwave warning might have 4 maps for Sunday to Wednesday:

  • The first map starts Sunday. It shows conditions for Sunday, Monday and Tuesday.
  • The second map starts Monday. It shows the conditions for Monday, Tuesday and Wednesday.
  • The maps starting Tuesday and Wednesday show the forecast for the next 3 days.

The maps differ because they:

  • use different observed and forecast information
  • cover different periods.

Heatwave warnings

We issue a heatwave warning for severe or extreme heatwave conditions.

These warnings alert Australians that a heat hazard is forecast within the next 4 days. They help the community prepare for and lessen the impacts of a heatwave event.

What's in heatwave warnings

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 in heatwave warnings

The warnings include action statements that match the heatwave severity. These have been agreed with our partner health and emergency service agencies across Australia.

Our heatwave warnings complement heat health messages provided by state and territory agencies.

Issuing heatwave warnings

We issue a heatwave warning for your weather district when a severe or extreme heatwave is expected. To learn about heatwave classifications, see What is a heatwave?.

How heatwave warnings are issued:

Time issued:

  • 3 pm local time for all states and territories except Western Australia.
  • 2 pm local time in Western Australia.
Four maps of Queensland. 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 (Sunday 2/1/22) shows a widespread low-intensity heatwave with severe areas in the east, centre and west.
Example maps for a heatwave warning. The warnings include 4 maps, each showing heatwave intensity for 3 days into the future.

Heatwave forecasts

Calculating the heatwave forecast

We calculate heatwaves using the observed and forecast maximum and minimum temperatures for the next 3 days. We compare this to:

  • what would be considered hot for that location
  • observed temperatures over the past 30 days.

The calculation allows for people's ability to adapt to heat. For example, the same temperature feels different to residents of Perth and Hobart. A 35° day will feel warmer to people who live in Hobart, as they are used to cooler temperatures.

This forecast method means that:

  • after a relatively cool period, a sharp and sustained increase in temperature shows up in the heatwave forecast
  • it takes higher temperatures to meet heatwave criteria at the end of summer, than earlier in the season.

What's in heatwave forecasts

A heatwave forecast consists of 5 maps for the next 5 three-day periods – covering the next 7 days in total.

Each map shows:

  • areas where heatwave conditions are forecast
  • the intensity heatwave conditions are expected to reach.
Map of Australia showing a forecast heatwave stretching from Broome to Gympie. Red sections indicate the heatwave will be extreme near Broome, east of Kakadu and south of Cairns. Around the red sections, orange areas indicate a severe heatwave, while yellow areas indicate low intensity. Text below the map says Three-day Heatwave Forecast for Monday, Tuesday and Wednesday starting Monday 22/11/2021. The Bureau's logo is top left and copyright details are below the map. Issued date is bottom right.
Example of a heatwave forecast map

Heatwave assessments

A heatwave assessment consists of 2 maps for the previous 2 three-day periods.

Each map shows the:

  • location of heatwave conditions
  • level of intensity.

The map is accompanied by text describing the conditions.

Heatwave forecasts and warnings

View our Heatwave Service for Australia.

Preparing for a heatwave

Visit the Australian Red Cross and your state or territory public health website. You'll find their details on the Heatwave knowledge centre page.