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Contributed by Frank Lepore (NHC)

Since 1978, the United Nations' World Meteorological Organization, a group representing some 120 different countries, has used pre-determined lists of names for tropical storms for each ocean basin of the world. The Atlantic basin, which falls under Regional Association IV, has a six year supply of names with 21 names for each year. Why 21 names? Well, the letters Q, U, X, Y and Z are not used because names beginning with those letters are in short supply (you would need at least 3 male and 3 female names for each letter, plus a back-up supply for those retired). Think about it; how many men and women do you know whose names begin with these letters?

When a damage or casualty producing storm like Mitch, Andrew,or Katrina strikes, the country most affected by the storm may recommend to the World Meteorological Organization's Regional Association that the name be "retired." Retiring a name is an act of respect for its victims, and reduces confusion in the insurance, legal or scientific literature. A retired name is replaced with a like-gender name beginning with the same letter. For example, Honduras recommended (1998) the name Mitch be retired and proposed the replacement name, Matthew, for consideration (and vote) by the 25-member countries of the Regional Association-IV. Sixtyeight names have been retired in the Atlantic basin.

The names used on the list must meet some fundamental criteria. They should be short, and readily understood when broadcast. Further the names must be culturally sensitive and not convey some unintended and potentially inflammatory meaning. The potential for misunderstanding increases when you figure that in the Atlantic basin there are twenty-four countries, reflecting an international mix of English, Spanish and French cultures.

Typically, over the historical record, about one storm each year causes so much death and destruction that its name is considered for retirement. This means that in a "normal" year, the odds are about 1 in 8 of requiring a replacement name, given that over the last 57 years (of reliable record) we've averaged slightly over 8 tropical storms and hurricanes per season (actually 8.6). So, it's more likely that letters/ names toward the front of the alphabet (letters A through H) might be retired.

The Director of the OAR has a rather large file folder of nominated names that have already been submitted. The next time the need arises and it's a storm affecting mainly the United States, the NHC Director will be casting about for a replacement tropical cyclone name. He will take out THE file to make a selection. But as we say, it's pure chance from there.