The availability of free space optics (FSO) links remains an important question in wide-scale deployment of the technology. As with microwave links, for any given terminal design there will be a correlation between the range between nodes and the link availability. This correlation will change depending on location and season. The key variables are the atmospheric transmission and the level of scintillation, which may themselves be correlated. The Naval Research Laboratory’s Chesapeake Bay (CBD) Lasercom Test Facility (LCTF) maintains a full suite of optical instruments characterizing a path that goes 16 km across Chesapeake Bay. In addition, a 100 Mbps FSO link is continuously run to gather link quality statistics. In this work we examine data from CBD including scintillation index, transmission, and packet error rate, as well as local weather data. With this data, as well as link models, we determine to what extent we can predict the actual link availability at CBD and at other locations.