The Special Sensor Microwave Imager Sounder (SSMIS) system is a passive, conical-scanning, microwave radiometer system operating on the Defense Meteorological Satellite Program’s (DMSP) satellites. The satellites will be placed into sun synchronous orbits at a normal altitude of 833 kilometers (km). The SSMI/S sensor integrates the SSMI, SSM/T1, and SSM/T2 sensors into one sensor with higher resolution than the old sensors and also includes a mesospheric temperature sounding capability. The radiometer system rotates about a vertical axis on a conical angle of 45 degrees from nadir. This scan pattern, combined with the 144-degree clear field of regard, result in a constant angle of incidence on the Earth of 53.1 degrees and a swath width of 1,707 km. The system passively measures brightness temperatures of the Earth’s surface, and the intervening atmosphere at 24 discrete frequencies from 19 to 183 GHz and in various altitude regimes of up to 55 km with 19 frequency channels and to 110 km with 6 channels for the upper air temperature sounding. These measurements will provide retrievals of data parameters to 30 km (basic system) and 73 km (with upper air sounding). After telemetering the acquired frequency channel data to the Air Force Weather Agency (AFWA), the measured raw data is processed by using matrix inversion algorithms to produce imaging and sounding parameter data for storage in databases. Forecasters from AFWA perform tropical cyclone fixing and analysis using display programs and these databases. Meteorological Modelers use these databases to improve current Numerical Weather Prediction models. The software also performs verification and validation of the retrieved data and updating of the inversion algorithms to maintain high retrieval accuracy. Additional processing involves monitoring the radiometer system performance data. If the satellite is launched prior to the date of the conference, satellite imagery will be presented.