When the storms are in their infant stages as just a general area of low pressure that has the potential to strengthen, they're usually given the name "Tropical Depression" (it's not known if it got that name from ruining sunny tropical vacations.) It doesn't get a name like "Betty" or "Donald" just yet, instead, it gets a sequential number, like "Tropical Depression 3."
If the storm's peak winds become greater than 39 mph, then it's now a "tropical storm" and it gets a real name from the National Hurricane Center, like "Tropical Storm Barry."
If the storm continues to grow and reaches wind speeds over 74 mph, it's then a hurricane, but it keeps its identifying name for continuity sake.
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