Weather forecasting is about predicting the state of the atmosphere in the future. The main purpose for forecasting is to give information to activity planning and preparing for weather events. Weather related events have an effect to the activities performed by the greater public but also various socio-economic sectors are influenced by the weather. Knowing what the weather will be in the future helps to plan what to do and when.
Also the outputs of Numerical Weather Prediction models are used as input to assess the state of the atmosphere and what is going to happen. All this information is combined with weather forecasts based on the meteorological know-how, and issued through public media and other dissemination channels to those that require the information for their decision-making.