Feasibility study including analysis and experiment performed in Phase I indicated that several singled-ended optical scintillometer and retro-reflector pairs installed on towers or poles are able to develop a vertical profile of near ground atmospheric turbulence and wind measurements in airport environment. In Phase II, OSI proposes to design, fabricate and test a prototype optical vertical profile system for atmospheric turbulence and crosswind measurements to provide critical atmospheric parameters for wake vortex decaying forecasting modeling. Several scintillometers will be built with the goal to demonstrate their ability to meet performance, size, weight, and packaging requirements for airport operations. An analytical and field test program will be conducted for further performance improvement of a vertical profile vortex detection system using optical scintillometers to measure near ground level crosswind, turbulence, and wake vortex on an airfield. The results of near ground vortex measurements plus the ground vortex measurements by double-ended optical scintillometers will provide the necessary assessment to design a crosswind, turbulence, and vortex detection system as a decision support tool for NASA's Airspace Systems (AS) Program to improve airport capacity and safety. The vortex detection system could also measure downdraft on the runway. The instrument will provide real-time continuous measurements of convergence and divergence along the runway. Vertical winds, and hence the downdraft, can be derived from the measured divergence. The proposed vortex detection system will also be able to provide critical large area wind information. By incorporating this valuable information into the low-level wind shear modeling, it will greatly enhance the performance of the present airport low-level wind shear systems.