Weather: The Name Game
The Name Game
Prior to World War II, hurricanes were named according to their latitude and longitude. That method became confusing. So during the war, the storms were given names such as Able, Baker, and Charlie. But the number of Ables and Bakers became so great that this naming scheme became confusing, too. So in 1953, the National Weather Service began using female names. Later, in the 1970s, male names got into the mix—for Pacific storms in 1978 and Atlantic storms in 1979.
I am still waiting for Hurricane Mel, but the outlook for that is mostly cloudy. Lists of names are drawn up for a six-year rotation. Separate lists are drawn up for the Atlantic and Pacific. If a storm is responsible for noteworthy damage and destruction, the name is retired—something like a basketball jersey. But if the storm never does much, its name is repeated in six years. Tropical depressions do not receive names, but as soon as a system reaches tropical storm status, it earns a name. In the Gulf and Atlantic, about 10 named storms occur each year. In the Pacific, the alphabet could be exhausted—the wider oceanic area favors more development there.
Some hurricanes do reach super-storm status and are classified by an intensity scale. It is called the Saffir-Simpson scale, after the people who devised the scheme. See the following figure for a general description of the different intensities.
Category | 1 | 2 | 3 | 4 | 5 |
---|---|---|---|---|---|
Pressure (mb) | >980 | 965-979 | 945-964 | 920-944 | |
Pressure (in) | >28.94 | 28.50-28.91 | 27.91-28.47 | 27.17-27.88 | |
Winds (mph) | 74-95 | 96-110 | 111-130 | 131-155 | >155 |
Winds (kph) | 64-82 | 83-95 | 96-113 | 114-135 | >135 |
Storm Surge (ft) | 4-5 | 6-8 | 9-12 | 13-18 | >18 |
Saffir-Simpson scale.
Weather-Watch
A tropical storm watch is issued when tropical storm conditions are considered possible within 36 hours. That watch is elevated to a warning if those conditions are considered likely, usually within 24 hours. A hurricane watch and hurricane warning work the same way, with the watch issued when hurricane conditions are considered possible within 36 hours, and a warning issued when those conditions are expected.
Braving the Elements
Two Category 5 storms are known to have hit the United States, but only one has ever reached the mainland. In 1969, Hurricane Camille reached Category 5 status and slammed onto the mainland in Louisiana and Mississippi. The other Category 5 storm struck the Florida Keys on Labor Day 1935. It was called the Labor Day hurricane and stayed off the mainland, but technically hit the United States in the Keys. Hurricane Andrew in 1992 was borderline between Categories 4 and 5 when it pushed into Florida. Hurricane Hugo, which hit South Carolina in 1989, was a Category 4 storm. The Great 1938 Hurricane, which hit New England, was a strong Category 3 system.
Excerpted from The Complete Idiot's Guide to Weather © 2002 by Mel Goldstein, Ph.D.. All rights reserved including the right of reproduction in whole or in part in any form. Used by arrangement with Alpha Books, a member of Penguin Group (USA) Inc.