Summary

Two numerical models are used to investigate aspects of thunderstorm dynamics and thunderstorm initiation in the northern Alpine foreland. The first, an isentropic model of airflow over and around the Alps, is used to investigate flow patterns favourable for the initiation of deep con-vection in the region. It is found that a stably-stratified southerly flow towards the Alps leads to a southwesterly flow in the Alpine foreland, a situation most often found during thunderstorm periods, and to the formation of a gravity wave in the lee of the Alps. This wave is accom-panied by raised isentropes which, in reality, would lead to a reduction in static stability and convective inhibition as well as an increase in convective available potential en-ergy. The second model, a cloud model, is used to study the development of an observed squall line over southern Bavaria. The model is initialized with wind, temperature and moisture profiles from a radiosonde sounding ahead of the squall line and the squall line is initiated by an ar-ray of thermal bubbles. The model simulation is used to interpret the evolution of the squall line. 1