The case studies will examine cloud resolving simulations made with the WRF-ARW core and will use high-resolution data assimilation of satellite and radar data to produce realistic initial conditions. The primary questions to be addressed in the analysis of model results are (1) what is the initiation mechanism? (2) what is the propogation mechanism? (3) what is the organizational structure that permits a relatively long lifecycle? (4) what processes allow strong winds to penetrate to the surface through the nocturnal stable layer?