by David Murphy
The eye of the hurricane is the storm system's center, often visible on satellite images as a cloudless hole near the middle of the storm. The eye is cloudless because the air inside it is sinking, a process that generally leads to dry air. Remember: clouds form in moist, rising air and evaporate in dry, sinking air.
As the hurricane develops, it produces its own internal circulation, where air around the perimeter of the storm is rising (forming all those rotating clouds) and the air in the middle of the storm is sinking to replace all the air that's been drawn up from the surface. While the outer portion of the hurricane contains rain, lightning, an occasional tornado and plenty of strong wind, the weather inside the eye is peaceful, sunny and warm. To be caught within the eye of a hurricane means you have experienced the best and worst the storm has to offer, because the only way to get in and out of the eye is to ride out the hurricane's most powerful winds, located just around the eye's edge.
In smaller storms, the eye may not be visible, as the amount of sinking air required to keep the storm circulation going is not all that great. Also, eyes can be slanted and hidden from satellite. But as the storm grows in intensity and the demands of the storm increase, the eye usually grows large enough and straight enough to see. The eye of hurricanes typically grow to about 20-30 miles in diameter. The eye is usually not perfectly round, being tugged at the edges by the storm's fury. It often wobbles in a strong storm and sometimes forms a pair of walls that overlap, giving the impression of two, overlying eyes. Both the wobbling and the overlapping eye appearance are signs of a very strong storm.