Weather Whys; Eye of a Hurricane

This is Weatherwise. Satellite photography can point out one of the most striking features of a mature hurricane. It's eye. Looking like a small hole in the center of the storm, the eye is a relatively clear area which may be 10 to 50 miles in diameter. It's also the part of the storm where the lowest surface barometric pressure is recorded. Throughout the ages, the eye may have seemed like a cruel joke to hurricane victims who weren't familiar with the structure of those immense storms. After all, in a hurricane, the winds and rain reach their peak, then suddenly they stop and the sun comes out. A few fair weather type clouds may even be visible. For some, that seems to be a sign they can emerge from their shelter and be thankful the storm has passed. Not waiting on the other side of the calm is even more of that same cyclone. The eye is enclosed by a ring of very intense thunderstorms called the eye wall.

Embedded in a hurricane are a lot of organized severe thunderstorms and those near the middle of the cyclone are the most severe of all. Those storms release huge quantities of energy in the form of heat which results from the condensation of water vapor. Warm, moist air arises through a process known as convection. And because of the intense convection of the storms in the eye wall, an area of high pressure develops above the center of the hurricane. And it's that area of high pressure that causes the eye. Whether wise is produced with the assistance of the National Weather Service forecast office and the National Severe Storms Laboratory, both in Norman, Oklahoma, and the Cooperative Institute for Mesoscale Meteorological Studies, the Oklahoma Climateological Survey, and the School of Meteorology, all at the University of Oklahoma. And for weather wise, I'm Drew Barma.