An isolated dynamic microburst is modelled in the laboratory by releasing an elevated volume of salt water solution which is slightly heavier than ambient fresh water, allowing it to fall onto a horizontal plate and develop into a turbulent microburst vortex ring. This experimental model exhibits many of the features of naturally occurring microbursts which are known to be a hazard to aviation. Flow visualization methods are used to observe the event and a high resolution video camera is used to record it. In the current investigation hot film velocity measurements are made at a number of radial positions near the ground. Realistic estimates of the wind field in real microbursts may be obtained from these measurements by means of a previously developed scaling law. Flow visualization and velocity measurements support a description of the microburst structure in its transition from a vortex dominated flow to a radial gravity current in its late stages.