The future success of the offshore wind industry relies in part on favorable conditions for financing of projects. To bring these conditions about the industry must develop a good level of understanding of all technical risks affecting energy production. One of the most significant of these risks is the long-term wind resource prediction for the site, which is contingent on the accuracy of the measurements and models utilized in the analysis. Uncertainties associated with the spatial variation of wind resource can be mitigated to a large extent through the gathering of wind data from a high quality on-site meteorological mast. However, this approach can be perceived as unattractive to developers because of the high costs of such an installation - especially for projects which are yet to receive the necessary planning consents. This paper presents new wind resource maps covering the Atlantic coast of the U.S., and the Great Lakes. An innovative approach has been adopted in the derivation of the wind map through the combination of three advanced wind resource methodologies: Earth-Observation (or satellite-mounted) data, Mesoscale modeling, and surface measurements. These methods have been combined in an integrated fashion in order to arrive at a consistent, credible offshore wind resource maps for North America, which are presented in the paper at high resolution. The wind map may be used for preliminary site assessments as well as later in the development phase, where it may be utilized as part of formal pre-construction energy production assessments.