NWP Grid Editing at the Met Office

Abstract

Abstract Over the past few years the way in which central forecast guidance is disseminated by forecasters in the Met Office headquarters has been changing, with an increasing reliance on modification of variables’ output from NWP models. The editing of grids of forecast data at the Met Office Operations Centre in Exeter is described, and two case studies are presented. Results of verification of modified versus raw fields are shown, presenting the concept of “lead time gain” as a unifying measure of relative forecast accuracy. At all lead times net lead time gain outweighs time spent considering and effecting modifications.