In situ wind and turbulence measurements play a key role in the support and validation of Earth science missions using spaced-based technology. NASA has been using Unmanned Aerial Vehicles (UAVs) in support of these Earth science missions, but the current UAVs do not have sensor packages to make science quality measurements of parameters including three-dimensional wind, turbulence, temperature, humidity, and pressure. AeroTech will develop 3-Dimensional Wind and Turbulence Measurement System for UAVs that is based on thermal anemometer technology and that will measure and resolve science quality wind vector and turbulence information throughout the flight envelope. The System will provide high quality data that will improve NASA's ability to validate, verify, and supplement spaced-based measurements taken during missions. Phase I will assess the capability of the thermal anemometer sensor portion of the system and finalize the system design. By the end of Phase II, the prototype system will have been developed, integrated into a UAV, and flight-tested.