This case study relates to the special case of the Pre-frontal convergence line of the Non-orographic convergence line conceptual model presented in SATMANU. (see Conceptual Models: Non-Orographic Convergence Lines ). The object of this particular study is a convergence line which developed ahead of a Cold Front over Poland during 29 May 2000. Some convective cloud cells already existed in the morning, but the actual convergence line started developing in the afternoon. When the development starts it is very rapid and the convergence line contains several mature cells of deep convection. Rain and thunderstorms are reported in many locations near the line. In the evening, when development has reached its peak, one can no longer distinguish the frontal cloud band from the thick convergence clouds.
The purpose of this study is to investigate the circumstances which caused this particular pre-frontal convergence line to develop and to compare them with those typical of the conceptual model Non-orographic Convergence Line.