Verification of the French operational high-resolution model AROME with the regional Brier probability score

Abstract

One composite index of the Météo-France AROME high-resolution forecast model results from the quantitative comparison of forecast rainfall and wind gusts with observations from surface stations. It is based on the regional Brier probability score in order to take into account some tolerance about the positions of storm structures. This approach is necessary to validate the added benefit of the AROME model compared with lower-resolution models. This index is used to monitor the continuous model improvements and the history of the last 4 years allows the impact of the successive upgrades of this operational model to be followed. The use of the normalization of models scores by persistence forecast scores enables most of the inter-annual variability to be removed.