This working group aims at providing a specific benchmarking framework for modelled air quality forecasts. Performance indicators have been developed to provide additional information about the capability of the forecasting system to detect and anticipate regulatory threshold exceedances and to check its ability to provide accurate forecasts (benchmarked against the ‘persistence model’). Future activities will focus on:

• 1 Assessing the clarity of the output of the forecast evaluation and discussing a possible tiered approach
• 2 Developing the AQI plots (multi-category contingency table, …) in view of improving the communication of results to non-experts
• 3 Documenting the procedure for experts (slideshow, video, training sessions)
• 4 Developing an open and user-friendly software platform
• 5 Further testing of the indicators