In the article some results of complex researches of precipitating mesoscale cloudness on Penza experimental meteorological range are resulted. On the data of special radar and meteorological observations the conditions of formation and development of 12 mesоscale cloudy zones and 14 of cloud-bands are analysed in air mass synoptic situations. Is shown, that these cloudy formations can develop with adverse for realization deep convection thermal conditions. In this case their development can be caused by presence of some dynamic factors.
