Forecast accuracy

Delivering timely and accurate forecasts

Measuring the timeliness and accuracy of our forecasts is a key part of assessing how we are performing. We do this by:

• recording the time that we issue forecasts, and
• comparing our forecasts to actual weather data recorded by our observation network.

To improve the accuracy of our forecasts, we increase the:

• understanding of the atmosphere through research
• resolution of our forecast models – spatial and temporal
• number and type of observations these models use
• skill and knowledge of our forecasters, staying up to date with the latest science.

Timeliness

Each year, we issue about 670,000 routine forecasts to the Australian community at scheduled times. These include:

• town and city forecasts
• state and district forecasts
• coastal waters forecasts
• high seas forecasts.

In 2024–25, 97.5% of our routine forecasts were issued on time.

Temperature forecasts

Temperature forecasts are considered accurate if they were within 2 °C of actual temperatures.

For 2024–25, next day maximum temperature forecasts were accurate 91.3% of the time. Overnight minimum temperature forecasts were accurate 82.8% of the time.

Rainfall forecasts

While weather elements like temperature and wind can be the same across large areas, rainfall varies much more. There can be big differences across small areas, as showers bring rain to some places and miss others. That's why our forecasts include information about the possible rainfall range.

The possible rainfall range indicates the rain that a location may receive. An example of a possible rainfall range is 2–6 mm. We say there is a 75% chance of more rain than the lower value in the range, and a 25% chance of more than the higher value.

For our next day rainfall range forecasts in 2024–25, there was more rain than the lower value 80% of the time. There was more rain than the higher value 21% of the time.

This indicates our forecasts are reliable. When we say there is a 75% and 25% chance of more rain than the values in a rain range, this is close to the true probability.

Wind forecasts

Wind information, particularly wind speed and direction, is important for marine activities, aviation, energy and agriculture. We have a network of wind recorders to verify wind forecasts across a range of urban, rural and coastal areas.

Across all urban, rural and coastal areas in 2024–25, 90.4% of wind speed forecasts for the next day were accurate to within 5 knots (about 10 km/h).

When looking at only coastal areas, 86.5% of forecast wind speeds were accurate within 5 knots.

Wave forecasts

Information about significant wave height is important for marine activities. Learn more about how we measure and forecast wave height on our Waves and swell page.

We use a network of Bureau and third-party waverider buoys to verify our wave forecasts. These are mostly deployed along Australia's southern and eastern coastlines.

In 2024–25, 86.8% of significant wave height forecasts were within 0.5 m of observations.

Flood forecasts and warnings

We provide flood forecasting and warning services for most major rivers in Australia. To do this, we work with other government authorities, such as:

• state and territory emergency services
• water agencies
• local councils.

To assess forecast performance, we measure the percentage of:

• peak river height predictions within a specified range of the observed peak – for example, 0.3 m
• forecasts that meet service level specification targets for lead time to customers.

In 2024–25:

• 80% of flood forecast peak height predictions met service level specification targets (typically within 0.3 m)
• 69% of flood forecast lead times met service level specification targets (which vary in lead time for each river).

Learn more about service level specifications on our Flood warning services page.