Weather4D Routing is the successor to Weather4D Pro. This eminent meteorological and routing application is based on weather and ocean data in GRIB format as well as the speed characteristics of the sailing boat (polar) and its minimum speed when operated with its engine. It now benefits from a new interface derived from the “Routing and Navigation” version. Weather Over 35 weather and oceanographic forecast models are available. Queries and downloads are fully customizable. The application makes it possible to create your own geographical zones and to select the characteristics of the GRIB files to download: choice of data, resolution, periodicity, file size, etc. GRIB files can be downloaded wherever you are from our servers through a regular or satellite internet connection. Weather4D Routing & Navigation displays the combined data as layered layers. All the data of a selected model is displayed by an animation in continuous time scrolling or in manual scrolling on the map. The weather forecast is displayed in one or two windows (iPad only), offering several display combinations of the same area: navigation and weather, weather and waves or currents, comparison of different models. The two windows can be disassociated for displaying the same area at different scales. Routing Weather4D Routing makes it possible to optimize sailing or engine, or mixed sail-engine routes. From a theoretical route, a routing algorithm will take into account wind force and wave height constraints. When sailing, the boat polar combined with wind and current forecasts will be used to optimize performance, comfort and safety. Several routes can be displayed to compare the outcome of different options: different forecast patterns, departure dates and times, selected constraint values. The routing can be restarted at any moment during navigation from the actual position of the boat.