Interpreting CASA radar imagery.

dBZ is a "unit" of radar reflectivity representing a logarithmic power ratio (in decibels, or "dB") in relation to the radar reflectivity factor, Z. Basically, dBZ measures the echo intensity of power that 'bounces back' to the radar as it emits waves that bounce off of precipitation. Therefore, a higher dBZ translates to a higher precipitation level. Moreover, one can infer that the higher the dBZ level is, the higher the 'rain rate' is.

Below is the dBZ legend used with our radar images.

The colors towards the blue end of the spectrum (towards the left), indicate a low dBZ, which in turn implies a low level of precipitation. Colors toward the red end of the spectrum imply a higher dBZ level, which then implies a high level of precipitation.