An experiment investigating introducing charge into a natural fog was conducted at Sonning Farm (51.48155 °N, 0.897154 °W), University of Reading, in Spring 2020. This archive contains data files from measuring instruments deployed there, for 15th and 16th March 2020, when fog events occurred. Measurements of droplet concentration were made with a LOAC (Light Optical Aerosol Counter), atmospheric electric field with a JCI131 electric field mill, and three-dimensional wind speed with a Gill sonic anemometer. Switching times of a negative corona ion source were also recorded.