This paper studies how shipping forecasts are constructed and shaped. A pilot corpus of ten shipping forecasts issued by the Met Office, on behalf of the maritime and Coastguard Agency, and broadcast by BBC Radio 4 has been collected for this purpose and examined in terms of its rhetorical structure. Adopting a genre-centred approach and making use of Swales's (1990) terminology, shipping forecasts are analysed and structured into a number of moves and steps. Findings are expected to help linguist researchers to gain knowledge of the textual organisation of shipping forecasts as a very particular type of oral discourse within the professions, and also, to provide maritime English teachers with genre-based tools that may contribute to enhance their teaching practices in maritime English classrooms.