What is the best distance that radars can see rain?
Radars images on the Bureau’s website display the rainfall echoes from clouds approximately 3000m above the ground. Due to the curvature of the earth, the radar beams optimal range is from 5 to 200km for this 3000m level. Beyond 200km, the radar is displaying rainfall echoes from clouds at higher altitude in the atmosphere and the radar image may not reflect what is happening on the ground. There are usually no echoes displayed very close to the radar because the radar beam does not scan directly above itself. This is commonly referred to as the “cone of silence”. The 512km composite images provide a more expansive coverage at a height of 3000 metres, by combining echoes from surrounding radars. However for remote radars it may not be possible to include other radars in the image and care should be taken when interpreting these images for distances greater than 200km away from the radar. Check the Optimal radar coverage for your nearest radar.
