Every day, millions of Australians check the bureau's radar maps to see what the skies are doing. But behind these simple images is some clever tech. So what is radar and how does it work?

Across Australia, you might have seen large white domes that look like a golf ball on a tee. That's actually a weather radar, and inside that ball is a rotating dish, or antenna, that detects precipitation.

Radar stands for radio detection and ranging and, as the name suggests, it works using radio waves. The dish sends out short pulses of electromagnetic waves at the speed of light. When these pulses hit water particles, they bounce back to the radar like echoes in a cave.

How long the pulses take to return to the radar determines the distance from the radar, and the strength of the return determines the type of precipitation. This information is converted to data on a map, which can be viewed on our website or app. A new image is produced every five minutes.

A colour scale shows rain intensity, with black marking the heaviest rainfall or sometimes indicating hail.

Australia has one of the largest radar networks in the world, with around 70 radars. They're generally placed in areas prone to severe weather, with large populations, or important to industries like agriculture and mining.

Radar does have some limitations. The curvature of the Earth means that the optimal range is between 5 and 200 kilometres. Beyond 200 kilometres, the radar might be showing rain that's falling high in the atmosphere, and this might not represent what's actually happening on the ground.

Even in the optimal range, radars can sometimes show virga, which is rain that is falling but evaporates before it hits the ground.

Another limitation is detecting low-level drizzle. This can be difficult to detect because the droplets are small and often form close to the ground below the radar's beam. The radar also can't scan directly overhead, creating what's known as a cone of silence.

Sometimes the radar can see things that look like rain but actually aren't. This is sometimes referred to as clutter. This happens because the beam is reflecting off things such as aircraft, flocks of birds, smoke or ash from fires, swarms of insects, or because of unusual atmospheric conditions where the beam is reflected back down towards the ground.

Permanent features such as buildings or mountains can get in the way of the radar beam, so we filter these out. That's why we try to locate radars in big open spaces.

Weather maps show the lowest possible observation from the radar, meaning what you see on the radar and what you experience on the ground are likely to match.

A number of our weather radars also have Doppler and dual polarisation capability.

Doppler radars measure precipitation speed, or velocity, towards or away from the radar and can help indicate severe weather. These radars don't measure total wind speed, ground-level conditions, or wind moving across the radar beam.

In addition, the dual polarisation capability sends and receives both horizontal and vertical waves, giving a clearer view of rain, hail and snow shape, size and composition. It also helps us remove clutter.

Radars pose no danger to the public. The constantly moving beam is angled up into the sky, away from people. We follow safety standards to protect our workers and restrict public access to the sites.

The radar is just one way that you can observe current conditions and works best when used in combination with other observations such as satellite imagery or automatic weather stations.