Radar detects precipitation intensity by sending out a beam of energy into the atmosphere.
When the beam encounters water droplets, it returns a percentage of this energy to the radar site. The larger the droplets, the more energy that is returned to the radar. On the radar image, these decibels are displayed in a variety of colors. Green colors represent light rainfall or snowfall, yellow colors correspond to moderate rainfall, and red colors relate to torrential rainfall. In other words, larger DBZ values mean higher intensity rainfall, and more yellow and red colors being displayed on the radar image.