Probability forecasts – Part 2: will people understand?

Abstract Ensemble weather forecasts have been in use for many years to help forecasters understand uncertainty in weather predictions but are now becoming core to some operational NWP systems. Part 1 introduced the rationale for ensemble forecasts and the production of useful forecasts. This Part 2 considers effective communication of probabilistic information and asks the question – will people understand? Literature surveys provide overwhelming evidence that people will understand probabilistic information and make better decisions, provided it is communicated effectively. The combination of suitable language, graphics and numerical probabilities can aid a large majority of people to benefit through improved decision‐making.