The unit dBZ is the logarithmic Scale for measuring Radar reflectivity factor.

dBZ = 10 log( Z mm6 / 1 m3)

This dBZ value calculated using above equation, is what usually we will see displayed on the radar screen or on imagery downloaded from the website.

As we know that some degree of transmitted power is likely to be returned to the radar antenna as a result of backscattering. hence feflectivity is basically a measure of how much power was scattered back to the radar from the target. Pls. note that stronger the targets will have higher levels of reflectivity and hence they return more energy. Hence stronger targets have higher reflectivity values; i.e. higher dBZ levels. dBZ is also related to the number of drops per unit volume and the sixth power of their diameter.