Mature Stage anvil top will form as the cumulus cloud has reached the stable layer of the stratosphere as more particles reach precipitable size, their mass inhibits upward motion, eventually creating downward-moving parcels that create a downdraft entrainment of surrounding drier air causes some evaporation within the downdraft - cooling enhances the downdraft evaporation of precipitation below the cloud base can enhance the downdraft downdraft reaches the surface, spreading out in all directions to create the cold pool and associated gust front the cold pool can act to enhance the updraft