The capability of making stereographic observations of clouds and their temporal changes from two simultaneously scanning geosynchronous satellites is a new basic meteorological analysis tool with a broad spectrum of applications. Stereo height measurements, because of their higher horizontal resolution and dependence on only straightforward geometric relationships, represent a big improvement over previously used infrared-based techniques. Verification using high altitude mountain lakes indicates that stereo cloud height accuracies of ±0.1–0.2 km are possible near reference points of known elevation. The smallest cloud features observed by the present operational geosynchronous satellites (GOES), which have spatial and temporal resolution of 1.0 km and 3 min, can be measured with height accuracies of ±0.5 km. Absolute stereo height accuracy, far from landmarks, is also about ±0.5 km if accurate navigation solutions are available for both satellites. Computer remapping of digital image pairs allo... Abstract The capability of making stereographic observations of clouds and their temporal changes from two simultaneously scanning geosynchronous satellites is a new basic meteorological analysis tool with a broad spectrum of applications. Stereo height measurements, because of their higher horizontal resolution and dependence on only straightforward geometric relationships, represent a big improvement over previously used infrared-based techniques. Verification using high altitude mountain lakes indicates that stereo cloud height accuracies of ±0.1–0.2 km are possible near reference points of known elevation. The smallest cloud features observed by the present operational geosynchronous satellites (GOES), which have spatial and temporal resolution of 1.0 km and 3 min, can be measured with height accuracies of ±0.5 km. Absolute stereo height accuracy, far from landmarks, is also about ±0.5 km if accurate navigation solutions are available for both satellites. Computer remapping of digital image pairs allo...