Describe the stages in the development of a hurricane. Describe a hurricane's basic geometry.

A hurricane starts as a tropical disturbance, which is a disorganized area of thunderstorms usually formed over warm ocean waters. This occurs when warm, moist air rises and forms clouds. As more air moves in and rises to replace the displaced air, a converging wind pattern emerges.

When the wind speeds in the tropical disturbance reach around 23 mph (37 km/h), it becomes a tropical depression. At this stage, there is still a low-pressure center, but a closed circulation of winds begins to develop around the center, and the weather system becomes more organized.

As the system continues to strengthen, the wind speeds can reach 39-73 mph (63-118 km/h), and it becomes a tropical storm. At this point, it is given a name. The system also starts to develop the characteristic counter-clockwise rotation in the Northern Hemisphere or clockwise rotation in the Southern Hemisphere.

The tropical storm turns into a hurricane when wind speeds reach 74 mph (119 km/h) or higher. The system becomes even more organized and starts to form a well-defined, cloud-free area known as the eye, which is surrounded by the most intense thunderstorms and rain bands, called the eyewall.

A hurricane typically has a circular or oval shape, with a diameter that can range from 60 to 1,500 miles (100 to 2,400 km). The storm is composed of different parts: the eye, the eyewall, and spiral rain bands. 1. The eye: The eye is a calm, cloud-free area located at the center of the storm, where the pressure is the lowest, and the wind speeds are the weakest. The eye's diameter can range from 2 to 40 miles (3 to 64 km). 2. The eyewall: The eyewall is a ring of the most intense thunderstorms and rain bands surrounding the eye. In this region, the wind speeds are the highest and the precipitation is the heaviest inside the hurricane. 3. Spiral rain bands: These are the bands of thunderstorms that spiral outwards from the eyewall. These rain bands can produce heavy precipitation and sometimes tornadoes. As a hurricane makes landfall, the rainbands are typically where the most severe weather is experienced. In summary, the development of a hurricane involves several stages, from a tropical disturbance to a tropical depression, then becoming a tropical storm, and finally a hurricane. The basic geometry of a hurricane includes a central eye, an intense eyewall, and spiral rain bands.