Schematic thunderstorm life cycle, not to scale. Developing stage: updrafts build a towering cumulus cloud and no rain reaches the ground. Mature stage: updrafts and downdrafts together, heavy rain, hail and lightning; the downdraft spreads out along the ground as cold outflow, and its leading edge, the gust front, reaches a windsock ahead of the storm and swings it round before any rain arrives there. Dissipating stage: downdrafts dominate, rain eases and the top spreads into an anvil; lightning and gusty surface winds remain possible.
