(Top) Surrounding the eye of the hurricane is a ring of thunderstorms, called the eyewall. Rainbands surround the eye of the storm in concentric circles. In the eyewall and in the rainbands, warm, moist air rises, while in the eye and around the rainbands, air from higher in the atmosphere sinks back toward the surface. The rising air cools, and water vapor in the air condenses into rain. Sinking air warms and dries, creating a calm, cloud-free area in the eye.
(Middle) Low pressure at the ocean surface in the heart of the hurricane draws in surrounding air. These spiraling winds pick up speed as they approach the eye, pulling more heat and moisture from the ocean surface.
(Bottom) The stronger the convection in the thunderstorms becomes, the more rain they produce. The more rain they produce, the more heat they release into the surrounding atmosphere, further fueling the storm.
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