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This change will be introduced on Tuesday 10 November 2015.
Naming convention for the 'Genesis category' of tropical cyclones
A "Storm Identifier" label is assigned to each separate TC feature identified in a forecast. This ID is formed by a number (between 70 and 99) and a letter that indicates which basin the cyclone belongs to (among eight basins). Strictly the letter shows the basin in which genesis occurred, so if a TC transfers from one basin into another, the identifier of the original basin will be retained. The range of numbers used was chosen to distinguish from real TC IDs (official reports) at any time. The basins are identified by the following suffixes (letters) which are appended to the end of each TC number:
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