Hurricanes evolve through a life cycle of stages from birth
to death.
A tropical disturbance in time can grow to a more intense stage
by attaining a specified sustained wind speed. The progression
of tropical disturbances can be seen in the three images below.
Hurricanes can often live for a long period of time as much
as two to three weeks. They may initiate as a cluster of thunderstorms
over the tropical ocean waters.
Once a disturbance has become a tropical depression, the amount
of time it takes to achieve the next stage, tropical storm,
can take as little as half a day to as much as a couple of days.
It may not happen at all.
The same may occur for the amount of time a tropical storm needs
to intensify into a hurricane. Atmospheric and oceanic conditions
play major roles in determining these events.
Below, in this satellite image from 1995, we can see different
tropical disturbances in each stage are evident. At the far
left, Tropical storm Jerry is over Florida, while Hurricanes
Iris and Humberto are further east, amongst a couple of tropical
depressions.
