Assessment of ECMWF forecasts: widespread rainfall events during the Indian summer monsoon

TitleAssessment of ECMWF forecasts: widespread rainfall events during the Indian summer monsoon
Publication TypeMiscellaneous
Year of Publication2009
AuthorsMujumdar, M, Molteni, F, Ghelli, A, Vitart, F, Dando, P, Slingo, JM
Secondary TitleTechnical Memorandum
Number580
Abstract

The skill of dynamical forecasts of widespread rainfall events (WSREs) over central India is examined using high-resolution models from the European Centre for Medium Range Weather Forecasts (ECMWF). The WSREs entail interactions between the large-scale monsoon circulation and the convective systems which are embedded within the boreal summer Inter Tropical convergence zone (ITCZ). A diagnostic analysis of the ECMWF forecasts of WSREs during 2007 is performed. Several features of the observed rainfall distribution and large-scale organisation of convection during WSREs are found to be realistically captured by the ECMWF forecasts. The paper acknowledges a potential wider scope for diagnosing the influence of remote and regional forcings on the organisation of large-scale convection. The appraisal could be extended to break phases associated with the evolution of large-scale suppressed convection.