Studies at the Air Force Research Laboratory are investigating methods for the incorporation of expected data sets from the Communication/Navigation Outage Forecast System (C/NOFS) satellite into existing scintillation specification models for an improved knowledge of the regional scintillation environment. Results from this research will form the basis for ground-based empirical scintillation forecast algorithms. One such study involves a determination of the extent to which correlations can be made for scintillation over a range of longitudes providing valid upstream (westward) forecasts of scintillation activity based on near real-time observations. Using archived data collected on Scintillation Network Decision Aid (SCINDA) receivers, a comprehensive study was conducted to numerically evaluate the correlation of scintillation on link pairings separated by varying degrees of longitude representing up to 3 hours in local time.