This U.S. Government system is subject to monitoring .
Reflectivity is the amount of transmitted power returned to the radar receiver.
The dBZ values increase as the strength of the signal returned to the radar increases. Each reflectivity image you see includes a color scale. The value of the dBZ depends upon the mode the radar is in at the time the image was created. The scale of dBZ values is also related to the intensity of rainfall. Typically, light rain is occurring when the dBZ value reaches 20.