We present LEOVISTA, a Cesium-based 3D visualization tool for post-simulation analysis of Vehicle-to-Satellite (V2S) communications. Unlike existing solutions, LEOVISTA offers high-fidelity, geospatially accurate rendering of vehicles, urban environments, and Low Earth Orbit (LEO) satellite constellations. The proposed solution allows users to interactively explore how satellite coverage and environmental factors impact Connected and Automated Vehicle (CAV) connectivity. LEOVISTA supports playback control, parameter inspection, and side-by-side scenario comparison, making it a powerful tool for both visualization and debugging of complex CAV simulations.