Final answer:
The final stage in the development of a mid-latitude cyclone is occlusion. This stage is reached after the cyclone has fully matured, and it signifies the diminishing and eventual end of the cyclone's life cycle.
Step-by-step explanation:
The last step in the classical cyclogenesis of a mid-latitude cyclone is occlusion. Classical cyclogenesis describes the life cycle of a mid-latitude cyclone and involves several stages.
It starts with cyclogenesis, where a cyclone begins to form. Next is the frontal wave stage, where the cyclone starts to take shape with a wave-like front. The maturity stage is when the cyclone is fully developed and has the most intense winds and precipitation. Lastly, occlusion occurs when the cold front catches up to the warm front, leading to a decline in the cyclone's energy and eventually its dissipation.