The Atmospheric Infrared Sounder (AIRS) instrument has produced a 6-year record of profiles of temperature and water vapor, along with trace gas amounts and cloud and surface properties. Because these quantities are retrieved from directly observed infrared and microwave radiances, they must be validated against high quality in situ observations. About 1900 radiosondes have been acquired over the AIRS mission for validation of AIRS temperature and water vapor profiles. Sondes were launched in close synchronicity with AIRS overpasses so they can be used to tightly constrain uncertainties on the AIRS retrievals. The sondes were launched at about 30 sites around the globe, covering a wide range of geophysical and interannual conditions. We describe the uncertainty estimates on AIRS temperature and water vapor retrievals, based on 30 or more matched dedicated radiosondes, at several sites and seasons.