SeaConditions is a public service providing oceanographic, sea state and weather at sea. Forecasts concerning the Mediterranean Sea are produced by numerical models using satellite observations and in situ data (e.g. opportunity ships and buoys). The computation is based on state-of-the-art ocean models, delivering detailed information with high spatial and temporal resolution. Forecasts for a time-span of 5 days, with a time resolution of 3 and 6 hours, are produced. SeaConditions provides the following information: - Oceanographic and sea state forecast that is: sea surface temperature, surface currents, significant wave height and direction, wave period and direction; - Meteorological forecast that is: air-temperature at 2 meter a.g.l., surface pressure, precipitation, cloud coverage, 10 meter a.g.l. wind. SeaConditions is a product of the TESSA project, executed by: Centro Euro-Mediterraneo sui Cambiamenti Climatici (CMCC), Istituto per l'Ambiente Marino e Costiero (IAMC-CNR), Links s.p.a. Meteorological forecasts are produced and certified by the Italian Meteorological Service (http://www.meteoam.it/). Oceanographic and wave forecasts are produced by the Mediterranean Forecasting System (gnoo.bo.ingv.it/mfs) of the Italian Institute of Geophysics and Vulcanology (INGV, Bologna, Italy).