Where does the data on which you base your forecasts come from?

Meteorological models for local areas, such as Poland or Europe, require initial atmospheric state and boundary data. The source of these data are global models, i.e. models that calculate the weather forecast over the entire globe. For the UM model, data is provided by the global UM model calculated at MetOffice in the UK. In contrast, the WRF models are fed by the GFS model calculated at NCEP in the USA. The UM and WRF models are not fed with direct observational data.

Observational data comes from meteorological services carrying out measurements in their own states, as well as collecting data from satellites and the sea. So, they are implicitly included in the process of weather forecast generation in our models, through the mechanism of their assimilation in global models.