ABP Marine Environmental Research Ltd (ABPmer) has been commissioned by DONG Energy Power (DONG) to undertake a metocean study for the proposed Westermost Rough Offshore Wind Farm. The proposed development site is within the Greater Wash area, established from the Strategic Environmental Assessment (SEA) for Round 2 offshore wind farms (BMT Cordah, 2003). More specifically, the site is located, approximately, 8km off the Holderness Coast with a development area of 35km2, providing the potential for up to 240MW of installed capacity with between 60 to 80 turbines. The project site has a relatively uniform seabed profile ranging in depth from around 11m to more than 20m Chart Datum (CD), and is devoid of any major sandbank features. The report within this series presents the study findings, which are presented according to the study specification.