Garmin G300 Pilot's Manual page 152

hazard avoidance
neXRAD i
Colors are used to identify the different NEXRAD echo intensities (reflectivity)
measured in dBZ (decibels of Z). "Reflectivity" (designated by the letter Z) is
the amount of transmitted power returned to the radar receiver. The dBZ values
increase as returned signal strength increases. Precipitation intensity is displayed
using colors corresponding to the dBZ values.
RADAR Legend
SATELLITE MOSAIC
Satellite Mosaic displays infrared composite images of cloud cover taken by
geostationary weather satellites. The Satellite Mosaic provides up to seven levels
of cloud cover.
RADAR Legend
ECHO TOPS
Echo Tops are derived from NEXRAD radar and indicate the highest altitude at
which precipitation is falling. Echo Tops at or above the altitude you select are
displayed, in 5,000 foot increments up to 70,000 ft. Echo Tops can be helpful in
determining the severity of thunderstorms.
134
ntenSity
Garmin G300 Pilot's Guide
NEXRAD Data
Satellite Mosaic/Cloud Tops Data
190-00921-00 Rev. D