In 1999, the Oklahoma Mesonet deployed infrared temperature sensors (IRTs) manufactured by Apogee Instruments, Inc. at 89 of its environmental monitoring stations. The 3-year dataset provides a unique opportunity to analyze long term, continuous, meso-scale observations of skin temperature across a large area. Several limitations of the sensor have been identified including: (1) failure of the calibration equation during the cold season, (2) difficulty in keeping the sensor's lens clean at remote sites, and (3) limited representativeness of local conditions due to the sensor's narrow field of view. Despite these limitations, the Oklahoma Mesonet's skin temperature network provides a wealth of information in understanding many land-atmosphere interactions. Not only can the observations be used in estimating the partitioning of latent and sensible heat flux, they can also provide beneficial "ground truth" estimates in validating remotely sensed estimates of skin temperature. A description of the IRT sensor, an evaluation of its performance, and selected case studies will be presented.