Typically, the radar antenna is located in the nose of the aircraft. Signals from the antenna are processed by a computer and presented on a screen which may be viewed by the pilots. Droplet size is a good indicator of strong updrafts within cumulonimbus clouds, and associated turbulence, and is indicated on the screen by patterns, colour coded for intensity. It needs to be noted that the frequency band of the radio waves (X band) is selected not to detect any cloud, small precipitation such as drizzle, fog or wind, as the droplets are too little or don’t exist. Some airborne weather radar systems may also be able to predict the presence of wind shear.

Weather radars send directional pulses of microwave radiation, on the order of a microsecond long, using a cavity magnetron or klystron tube connected by a waveguide to a parabolic antenna. The wavelengths of 1 – 10 cm are approximately ten times the diameter of the droplets or ice particles of interest, because Rayleigh scattering occurs at these frequencies. This means that part of the energy of each pulse will bounce off these small particles, back in the direction of the radar station.

Shorter wavelengths are useful for smaller particles, but the signal is more quickly attenuated. Thus 10 cm (S-band) radar is preferred but is more expensive than a 5 cm C-band system. 3 cm X-band radar is used only for short-range units (this kind of radar operates between 9 GHz and 10 GHz in the SHF band), and 1 cm Ka-band weather radar is used only for research on small-particle phenomena such as drizzle and fog W band weather radar systems have seen limited university use, but due to quicker attenuation, most data are not operational.

Radar pulses spread out as they move away from the radar station. Thus the volume of air that a radar pulse is traversing is larger for areas farther away from the station, and smaller for nearby areas, decreasing resolution at far distances. At the end of a 150 – 200 km sounding range, the volume of air scanned by a single pulse might be on the order of a cubic kilometer. This is called the pulse volume