What you are viewing is rain
and its intensity as it is falling. The intensity is represented by
colour that can be referenced from the legend at the bottom of each
image. Updated every 10 minutes.
For more information on interpreting the radar images I recommend you
read THIS
first.
Click on the "STILL IMAGE"
for the area and distance you want for the current still radar image,
or click on "LOOP" to view 4 sequential images at 128km
and 256km