Lightning strike to helicopters during winter thunderstorms over North Sea

Southerly winds over the Shetland Islands produce a wave flux which, in winter time, triggers convective clouds over the Atlantic Ocean. The clouds get electrified and produce isolated lightning flashes. In an attempt to describe the atmospheric electrical configuration produced by this meteorological situation, Méso-NH, a meso-scale non-hydrostatic model that delivers a 3D description of the convective cell was run. A microphysical and dynamical 1.5D model was then applied to simulate the vertical electrification within the cell. From the electrification study, the attachment model of ONERA was used to compute the zones on helicopters from which the lightning discharge can develop.