The calm, relatively clear central region of a mature tropical cyclone is called the eye.
The eye forms inside the ring of intense thunderstorms known as the eyewall. Air in the eye generally sinks, which suppresses cloud formation and produces lighter winds than those found immediately around it. The eye is often circular, but its shape and size can change as the storm strengthens or weakens.
A tropical cyclone’s most dangerous winds occur in the eyewall, not in the eye itself. When the eye passes over a location, skies may briefly clear and winds may become light. This calm period can be misleading because the opposite side of the eyewall arrives soon afterward, bringing severe winds from a different direction.
The eye is most clearly developed in strong, organized tropical cyclones. Weaker systems may have a ragged or cloud-filled center rather than a sharply defined one.