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Optical turbulence (OT) distorts light in the atmosphere, degrading the quality of service of free-space optical communications links. Some of the degradation due to turbulence can be corrected by adaptive optics. However, the severity of OT, and thus the amount of correction required, can vary considerably from location to location. In many cases, it is impractical and expensive to deploy instrumentation to characterize the climatology of OT, making simulations a less expensive and convenient alternative. The strength of OT is characterized by the refractive index structure function, C-n(2), which can be calculated from Numerical Weather Prediction (NWP) simulations. In this work, a modified version of the Weather Research & Forecast (WRF) NWP model is used to generate C-n(2) climatologies in the planetary boundary layer and free atmosphere, allowing for both point-to-point estimates of the Fried Coherence length (r(0)) and other seeing parameters. Nearly two years of simulations have been performed over various regions including the Desert Southwest and Haleakala and Mauna Kea on Hawaii. The results, which have shown good agreement with in situ turbulence measurements, are being used to assist engineers in free-space optical system design and site selection studies.