The M4 Weather Buoy is part of the Irish Weather Buoy Network and is designed to improve weather forecasts and safety at sea around Ireland. The buoy network provides vital data for weather forecasts, shipping bulletins, gale and swell warnings as well as data for general public information and research. Buoy data is also helpful for validating our operational models. The project is the result of successful collaboration between the Marine Institute, Met Eireann, the UK Met Office and the Irish Department of Transport, Tourism and Sport. This infrastructure has been part funded under the Marine RTDI Measure of the National Development Plan 2000-2006, co-funded by the European Regional Development Fund (ERDF). M4 is deployed directly north-west off Donegal Bay off the north-west coast of Ireland. None