Advances in Geosciences www.adv-geosci.net 1680-7340 1680-7359 26 11th EGU Plinius Conference on Mediterranean Storms (2009) 2010 10.5194/adgeo-26-19-2010 http://www.adv-geosci.net/26/19/2010/ http://www.adv-geosci.net/26/19/2010/adgeo-26-19-2010.html http://www.adv-geosci.net/26/19/2010/adgeo-26-19-2010.pdf 19 23 2010-06-30 Numerical study of a banded precipitation event over Italy P. Malguzzi M. Fantini m.fantini@isac.cnr.it A. Buzzi ISAC-CNR, via Gobetti 101, 40129 Bologna, Italy Satellite images of 30 October 2008 show the development over north-central Italy of rainbands and multiple waves during a strong south-westerly wind episode associated with a deepening synoptic trough and cold front passage. The event was studied by means of the ISAC model chain constituted of the hydrostatic model BOLAM and the nested non-hydrostatic model MOLOCH at 1.1 km resolution. Diagnostics of model output was performed to reveal the physical origin of the dynamical features and precipitation field as simulated. Based on our results we propose a theoretical framework in which symmetric instability underlies some of the observed precipitation patterns. Bennetts, D. A. and Hoskins, B. J.: Conditional Symmetric Instability – A Possible Explanation for Frontal Rainbands, Q. J. Roy. Meteor. Soc., 105, 945–962, 1979. Billet, S. and Toro, E. F.: On WAF-type schemes for multidimensional hyperbolic conservation laws, J. Comput. Phys., 130, 1–24, 1997. Drofa, O. V. and Malguzzi, P.: Parameterisation of microphysical processes in a non-hydrostatic prediction model, in: Proceedings of 14th Intern. Conf. on Clouds and Precipitation (ICCP), Bologna, Italy, 19–23 July 2004, 1297–1300, 2004. Fantini, M. and Malguzzi, P.: The slope of moist symmetric instability with water loading, J. Atmos. Sci., 65, 2922–2935, 2008. Malguzzi, P., Grossi G., Buzzi A., Ranzi R. and Buizza R.: The 1966 `century' flood in Italy: A meteorological and hydrological revisitation, J. Geophys. Res., 111, D24106, doi:10.1029/2006JD007111, 2006.