Why is Tropical Storm Bertha named Bertha? Here's how hurricanes get their names

Now that Tropical Storm Bertha is spinning in the Gulf, you may be wondering: How do tropical storms and hurricanes get their names?

The answer dates back decades.

The World Meteorological Organization maintains six alphabetical lists of names for Atlantic tropical cyclones. Those six lists rotate every six years, meaning the names used in 2026 will be used again in 2032 unless one is retired.

When does a storm get a name?

A developing storm doesn't receive a name right away.

It first becomes a tropical depression and is assigned a number. Once maximum sustained winds reach 39 mph, it is upgraded to a tropical storm and receives the next available name on the list.

If sustained winds strengthen to 74 mph, it becomes a hurricane while keeping the same name.

Storms weren't always named this way

Before the modern naming system, storms were identified in much less organized ways.

According to the World Meteorological Organization, some storms were named after ships they damaged. One storm became known as "Antje's Hurricane" after destroying the mast of a vessel named Antje.

For centuries, storms were also named after saints' feast days or the places they struck. Examples include the Great Galveston Hurricane of 1900 and the Labor Day Hurricane of 1935, which devastated parts of the Florida Keys.

Why name storms at all?

Naming storms makes it easier for meteorologists, emergency managers, the media and the public to communicate about dangerous weather.

It also helps people distinguish between multiple storms occurring at the same time, reduces confusion during emergencies and improves historical record-keeping and scientific research.

Who created the naming system?

The National Hurricane Center introduced official Atlantic storm name lists in 1953.

Meteorologists followed the alphabet, beginning each season with a storm whose name started with A.

Originally, only women's names were used. Beginning in 1979, the lists alternated between women's and men's names. Those six rotating lists remain in use today.

Why are some names retired?

When a hurricane is especially deadly or destructive, its name is typically retired so it is never used again.

The World Meteorological Organization makes that decision during its annual committee meeting. Retiring a name helps avoid confusion and shows sensitivity to communities affected by catastrophic storms.

While most name changes follow major disasters, the National Hurricane Center notes there have been rare exceptions. For example, Fern was replaced by Frieda in 1966 without an official explanation.

Why are some letters missing?

You may notice the Atlantic naming lists don't include every letter of the alphabet.

The letters Q, U, X, Y and Z are skipped because there are not enough common, easily recognizable names beginning with those letters to create six rotating lists.

The World Meteorological Organization also considers several factors when selecting names. They should be:

• Short and easy to communicate
• Easy to pronounce
• Appropriate across multiple languages
• Unique to the Atlantic basin

The lists also balance English, French and Spanish names while alternating between male and female names.

What happens if the list runs out?

Until 2020, the World Meteorological Organization turned to the Greek alphabet — Alpha, Beta, Gamma and others — if a hurricane season exhausted the annual list of names.

That happened only twice: 2005 and 2020, two of the busiest Atlantic hurricane seasons on record.

Following the record-breaking 2020 season, officials decided to stop using Greek letters. The organization said names like Eta and Iota became difficult to retire and created unnecessary confusion.

Beginning in 2021, any season that uses all of the regular names instead moves to a supplemental list of storm names.

Atlantic hurricane name lists

The World Meteorological Organization rotates six official name lists for the Atlantic basin, covering the years 2026 through 2031, along with a supplemental list used only if all regular names are exhausted during an exceptionally active hurricane season.

Now that Bertha is spinning in the Gulf… you may wonder… how do we come up with these tropical storm names anyway?

Well, there are six alphabetical lists of names for Atlantic hurricanes, each rotated through every six years, and they all originate from a group known as the World Meteorological Organization (WMO).

When a tropical system reaches certain criteria, it is first classified as a tropical depression and given a number.  When sustained winds reach at least 39 mph, it becomes a tropical storm and is officially given a name. Once maximum sustained winds reach 74 mph, the tropical storm becomes a hurricane with the same name.

Prior to the modern convention of naming storms, the practice was much more haphazard and after the fact. For example, a storm that hit a boat named Antje and ruined its mast was called "Antje's hurricane," according to the WMO. For hundreds of years, storms were named after saint days. Storms were also sometimes known by the name of a place they hit, like the Great Galveston Hurricane of 1900, or even named by the day and year they hit a certain location, like the 1935 Labor Day hurricane that devastated parts of the Florida Keys.