The National Hurricane Center watches for severe ocean storms.

The strongest, fastest winds of a hurricane blow in the area known as the eyewall. It surrounds the center, or eye, of the storm. The eye itself is calm by comparison.

Wind speeds in the most severe ocean storms can reach more than 250 kilometers an hour. Up to 50 centimeters of rain can fall. Some storms have produced more than 150 centimeters of rain.

These storms also cause high waves and ocean surges. A surge is a continuous movement of water that may reach as high as six meters or more. The water strikes low coastal areas. Surges are commonly responsible for about 90 percent of all deaths from ocean storms.

The National Hurricane Center in Miami keeps close watch on severe storms. It works with government officials and with radio and television stations to keep people informed. Experts believe this early warning system has helped reduce deaths from ocean storms in recent years.

But sometimes people cannot or will not flee the path of a storm. That is what happened in some parts of Louisiana when Hurricane Katrina struck.

Studies have found that some people do not leave a storm-threatened area because they have no transportation or money for transportation. Another reason is that they fear their property will be damaged by other people, if not by the storm. Yet another reason is that people do not want to leave their farm animals or pets.