Airborne weather radar is a type of radar used to provide an indication to pilots of the intensity of convective weather.
Modern weather radars are mostly doppler radars, capable of detecting the motion of rain droplets in addition to intensity of the precipitation.

Airborne weather radar is typically Xband, pulse modulated and operating in the 8-12 Ghz range (wavelenght approx. 3 cm).
The shape of the radar beam is very important in the design of a radar.
For purposes of airborne weather radar, a narrow beam is the most desirable because it concentrates more energy on the target, which means more energy will come back in the echo.
Flat Plate antennas are better than dish antennas and larger antennas are better than smaller antennas for concentrating the beam.
The pulse repetition frequency (PRF) of a radar will determine its maximum range.
The PRF must be long enough to allow the echo pulses to return from the maximum range target.
The longer the required range, the lower the PRF Scanning speed comes into play with the PRF since a high scanning speed and low PRF would cause targets to be missed.
At least one pulse should be transmitted per a beam width of scan.
Pulse width will determine the minimum range of the radar and also the resolution size of the target.
If a target is close and the echo is reflected back to the radar while the transmitter pulse is still being transmitted, then obviously that target will be missed.
Most radars I have worked with had a pulse width of less than 4 microseconds so this isn’t a problem.
Also, many radars will shorten their pulse width in map mode allowing a higher degree of resolution for ground targets such as shorelines or islands.