Unlike weather radars, such as the 3 GHz Doppler-Polarisation Radar at the Chilbolton Facility, MST radars are not particularly sensitive to hydrometeors; the radar return signals are dominated by the "clear-air" returns. However, an effect of rain-fall can be to `wash out' the high radar return signal power which is characteristic of the humidity field. The rain fall rate shown above is measured by the climate data logger at the radar site. The small scale structure seen between 0700 and 1000 UT in the example below suggests that (in this particular case) the radar may be observing rain bands passing over.