Recent developments in convection forecasting at ECMWF

The representation of convection in ECMWF’s forecasting system has been improved in recent years by advances in computing, substantial upgrades of both horizontal and vertical resolutions, and by major changes in the moist processes in the model. These developments have also opened up the opportunity for improvements of existing convective products and the development of new ones, such as lightning density diagnostics. As part of this ongoing initiative ECMWF is partnering with the European Severe Storms Laboratory (ESSL) on a number of projects. The computation of Convective Available Potential Energy (CAPE) and Convective Inhibition (CIN) parameters from the model has been revised and more versions of CAPE and CIN have been implemented and are made available to the forecasting community. CAPE and composite CAPE-shear parameters have been included in ECMWF’s Extreme Forecast Index (EFI) to help forecasting outbreaks of severe convection in the medium range. Alongside objective statistical verification, the convective EFI has been evaluated at ESSL’s Testbed recently. ECMWF has implemented ensemble vertical profiles to facilitate forecasting convection among other applications. ECMWF is working with ESSL on providing more parameters and products for forecasting deep, moist convection and its attendant severe weather. These include Storm Relative Helicity (SRH) and post-processed probabilities of various convective hazards such as large hail and severe wind gusts. Following its open data policy, ECMWF has also provided more probabilistic and deterministic graphical convective products on its website. This presentation will provide a brief overview of all these recent developments.