Initial Verification of IMPROVER: The New Met Office Post-Processing System

The Met Office is building a new post-processing system to make its operational products more consistent and efficient to develop. It emphasises ensemble forecasts and probabilities throughout, includes new science such as neighbourhood processing to improve the treatment of high-resolution forecasts, and is built in a modular way using modern tools such as Python and NetCDF. The new system has verification at its heart, measuring the performance of each stage to ensure they all add value. The same post-processing components can be run in both real-time and historic trial mode, so that new developments can be evaluated in advance using a broad range of verification diagnostics, as we do for Numerical Weather Prediction (NWP) systems. Probability and percentile forecasts are converted back to ensemble members to allow a range of standard ensemble verification metrics to be applied. This presentation will describe the IMPROVER verification strategy, and present some preliminary results from the earliest trials.