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STORMY WEATHER: HURRICANE FACTS By Sean Henahan, Access Excellence
 Click for latest satellite info Here is a handy list of answers to frequently asked question about hurricanes, tropical storms and tornados provided by the staff of the National Center for Atmospheric Research (NCAR). Don't miss the list of related web sites at the bottom of the article.
 Credits: Mark Thomas What is a hurricane? A:Each year a number of tropical disturbances-centers of low pressure-move westward across the Atlantic, Pacific, and Indian Oceans. Some of these become depressions, more organized disturbances with sustained winds of up to 39 miles per hour (63 kilometers per hour). If the winds become stronger, the system becomes a tropical storm and is given a name. If the winds reach 74 mph (119 km/hr), the storm is reclassified as a hurricane (other names, such as typhoon, are used outside of the Atlantic). Eventually, most of these systems either strike land and quickly weaken or recurve over the ocean, moving north and east as they become caught up in the midlatitude westerly winds and lose their tropical characteristics. What's the difference between a hurricane and a tornado? A:Tornadoes are spawned by thunderstorms, while hurricanes are made up of a number of showers and thunderstorms (which can themselves spawn tornadoes upon landfall). Hurricanes gather energy from the warmth of the summertime ocean. A hurricane's eye is as wide as 10 to 15 miles (16-24 km) and the winds around it are as strong as 150-200 mph (240-320 km/hr). Even the largest tornadoes are only about a mile across, although their winds can sometimes approach 300 mph (480 km/hr). Tropical storms can survive for weeks, while most tornadoes exist for much less than an hour. How many tropical systems occur on average each year? A:The tropical Atlantic and Gulf of Mexico-the sources of U.S. hurricanes-produce an average of nine named storms per year, with around six of those becoming hurricanes and two of those becoming intense hurricanes (those with sustained winds exceeding 130 mph or 209 km/hr). Last year, 1995, was the second busiest Atlantic/Gulf season on record, with 19 named storms. Globally, an average of 85 tropical storms and 45 hurricanes/typhoons form per year. What are the storm names for this year and upcoming years? A:Since 1953, Atlantic tropical storms have been named from lists now maintained by the National Hurricane Center. The lists featured only women's names until 1979. There are six lists used in rotation, with the names of the most severe hurricanes (such as 1992's Andrew) retired permanently.
Related information on the Internet CSU Tropical Meteorology Project This site, from Colorado State University, includes the latest seasonal outlooks from CSU professor William Gray --a comprehensive set of answers to frequently asked questions about hurricanes and other tropical cyclones. FSU Atlantic Hurricane Season Summary Maintained by Florida State University's meteorology department, this site offers a concise look at the 1996 hurricane season, with storm-by-storm links, as well as access to current warnings, satellite images, and reconnaissance reports. Atlantic Tropical Weather Center This privately maintained site includes a wealth of links to Web-based hurricane information. Because popular Web sites often become busy and thus difficult to access when a major hurricane approaches, the author includes several alternate addresses for frequently sought items, such as the latest storm intensities and projected tracks.
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