Liquid water content (LWC) is a microphysical parameter which is used to characterize fog/cloud. Higher density of LWC depicts dense fog, significantly reducing visibility and causing performance degradation of free-space optical links for a non-negligible amount of time. This paper presents and analyzes 5 months real time data of LWC, visibility and optical attenuation measured simultaneously in an attempt to quantify the affects of liquid water content on free-space optical communication link performance and to validate the relationship between aerosols's liquid water content and measured optical attenuations.