The problem of wave climate description and modeling are considered on both a short-term and synoptic basis. The wave climate is considered as an ensemble of conditions of spatio-temporal wave fields characterized by frequency-directional spectra. Using an expanded set of wave and wind characteristics makes it possible to correctly introduce the concept of a wave weather 'scenario' and to use it to evaluate vessel safety. The mathematical basis of the short-term wave description is by the representation of the stochastic processes by a generalized autoregressive model (ARM) and related models of periodically correlated random process. An ARM is used to generate space-time realizations of the wave surface of any short-term duration. Application of the aforesaid model takes into account the true stochastic process (lack of repetition in quasi-steady implementation of the process inherent in other models of wind waves). Ways of treating synoptic and seasonal variability of wave forecasts for a specific geographic region are also described. Here, for the first time using the general positions of stationary wave processes and non-stationary synoptic processes of average wave height variation are combined. In this case we have nested mathematical models of the same type.