Modelling study of the IOP2 cold front of the FRONTS 87 experiment

Abstract

On 11-12 November 1987, a frontal system associated with an intense narrow cold frontal rainband was observed over the Channel between England and France. This case constitutes intensive observational period 2 (IOP2) of the FRONTS 87 experiment. It was an ideal example of upper-level and low-level jet coupling with substantial ascending motions and precipitation. The frontal system is analysed, in this paper, using the mesoscale non-hydrostatic model CSU/RAMS. The model uses a two-way interactive nested grid structure and full cloud microphysics parameterisation at various levels of complexity. The model results are compared with previous numerical investigations of this case as well as with observations obtained from the experimental network deployed during the campaign. The model succeeded in representing the frontal structure at meso- and convective scales, taking into account the large scale forcing; thus it is an important tool for the study of secondary cyclogenesis observed during the FASTEX campaign.