WeatherOnline is a free, advertising-supported weather information and forecasting service covering the United Kingdom, Ireland, Europe, and destinations worldwide. It offers local and postcode forecasts alongside short- and longer-range outlooks, including morning updates, weekly forecasts, monthly guidance, and seasonal outlooks. Visitors can explore current conditions, temperatures, wind, pressure, humidity, rainfall, and other weather measurements, as well as forecasts presented through maps, graphs, and tables.

The service provides radar, satellite, lightning, webcam, and tropical storm information, plus specialist charts and weather warnings. Its marine and sailing coverage includes forecasts and resources for waters such as the North Sea, Baltic Sea, and Mediterranean. Additional tools include climate graphs, historic weather data, a climate finder, and a travel planner. WeatherOnline also publishes weather-related information and features on meteorology, climate, wind, and weather lore, with sections for sports and winter sports. For agricultural users, it lists daily and hourly crop forecasts, crop disease and protection information, spray-window guidance, and irrigation forecasts. Mobile and business-to-business services are also featured.