Currently rain radar in the Netherlands
The operation of a precipitation radar is based on the principle that a part of the emitted electromagnetic radiation is reflected by precipitation particles, and is collected again in the radar system. The strength of the reflected electromagnetic radiation is a measure of the precipitation intensity. The time difference between sending and receiving is a measure of the precipitation situation.

 Light rainfall 
 Moderate precipitation 
 Moderate precipitation 
 Strong precipitation 
 < 1 mm 
 1 - 2 mm p / hour
 2 - 5 mm p / hour
 5 - 10 mm p / hour;
 10 - 99 mm p / hour
 > 100 mm p / hour

Every quarter of an hour, a picture is compiled from the observations of the two gravitational graders.
The precipitate is shown in a precipitation image with a number of colors that are an indication of precipitation intensity. By presenting the precipitation images in sequence an impression regarding the evolution of precipitation, change in intensity can be obtained, pulling direction and rate.