The eye of a storm is a roughly circular area, typically 30–65 kilometers in diameter. It is surrounded by the eyewall, a ring of towering thunderstorms where the most severe weather and highest winds occur. A large ragged eye is a non-circular eye which appears fragmented, and is an indicator of a weak or weakening tropical cyclone.
About Eye (cyclone) in brief
The eye of a storm is a roughly circular area, typically 30–65 kilometers in diameter. It is surrounded by the eyewall, a ring of towering thunderstorms where the most severe weather and highest winds occur. In weaker tropical cyclones, the eye is less well defined and can be covered by the central dense overcast. A large ragged eye is a non-circular eye which appears fragmented, and is an indicator of a weak or weakening tropical cyclone. The eye is the location of the storm’s minimum barometric pressure—where the atmospheric pressure at sea level is the lowest. It can be as much as 15 percent lower than the pressure outside the storm, especially near the center of the cyclone, where the air is warmer than its surroundings. A typical tropicalcyclone will have an eye of approximately 30-65 km across, usually situated at the geometric center. Eyes can range in size from 370 km to a mere 3.7 km – across. While it is uncommon for storms with large eyes to become very intense, it does occur, especially in annular hurricanes. As the storm gains strength, stronger updrafts build up in the upper levels of the atmosphere. This results in the formation of an upper level anticyclone, or an area of high atmospheric pressure. Outside the eye, air flows outward outward anticyclically above the tropical Cyclone, forming a small portion of the most intense weather. The storm then develops two concentric eyewalls, which can take place anywhere from fifteen to hundreds of kilometers outside the inner eye.
In most cases, the outer eyewwall begins to contract soon after its formation, which chokes off the outer eye and leaves a much larger but more stable eye. Storms with pinhole eyes are prone to large fluctuations in intensity, and provide difficulties and frustrations for forecasters. They can also be difficult to predict due to their large size and unpredictability, and are often difficult to forecast in advance of a cyclone’s formation. A storm with a large, clear, and circular eye is sometimes referred to as a pinhole eye, or a small, clear and circular hurricane eye, which is sometimes called a large hurricane eye. This is due to the fact that the storm develops rainbands which start rotating around a common center. As a storm develops, stronger thunderstorms and stronger convection form at a certain distance from the storm developing storm. Since heavier rain areas mark the storm’s developing storm, the heavier rain mark areas begin to build up and air begins to drop in levels. This builds up the upper air pressure at the storm center, pushing the air towards the center and causing a positive feedback loop, causing a small-up loop to form. This feedback loop leads to the creation of an anticycling loop, which builds up a small section of high-pressure air above the storm. This leads to a small area of atmospheric pressure above the central overcast, the most prominent of which is the eye.