How Are Hurricanes Named? Here’s What You Need to Know

2019’s hurricane season in the North Atlantic Ocean is expected to last until November 30th. Over the past few months, storms like Dorian, Barry and Imelda have caused widespread damage and destruction. Dorian, which grew to a category 5 storm, devastated the Bahamas, leading to over 50 deaths and the decimation of island communities. Imelda, a tropical storm, led to dangerous flash flooding in Texas.

Every year, tropical storms tracked by the National Hurricane Center are given a specific name when they reach the speed of 39 mph. (They retain that name if, or when, their speed is tracking to hurricane levels.) Here’s what you need to know about that process, and why it’s important.

Why do we name hurricanes?

According to the National Hurricane Center, hurricanes are named to streamline messaging and communications. Short, distinctive names are more easily identifiable, and also cause less confusion when sharing important information across weather stations, and with the media and the general public about a storm’s tracking, path and predicted impact.

The National Hurricane Center began formally naming storms in 1950. At first they were named from a phonetic alphabet (Able, Baker, Charlie, and so on), but this method was changed in 1953 in favor of using alphabetized female names. This practice had previously been used during World War II.

The first tropical storm to receive a female name was tropical storm Alice in 1953, according to the National Hurricane Center. Alice hit Florida, Cuba and Central America in late May and early June of that year.

In 1978, men’s names joined the storm list, alternating with the female names. So a storm name with an A, like Anne, would be the first in any given year, followed by B for Bernard, for example.

“It made sense to broaden the pool of names and make them focus less on hurricanes as female entities only,” Jim Elsner, a professor of geography at Florida State University tells TIME. “I would imagine that it was viewed somewhat sexist.”

The first storm with a male name was hurricane Bob, which hit the United States Gulf Coast in 1979.

Before the use of short names, hurricanes had been categorized by latitude and longitude numbers. Although this was easy for meteorologists to track, it was widely seen as confusing for the general public.

How do hurricanes get their names?

The World Meteorological Organization (WMO) is now responsible for the lists of hurricane names. Specific to the North Atlantic ocean, the WMO keeps six lists of 21 male and female names that are used in rotation, and recycled every six years. (There are no names that start with the letters Q, U, X, Y or Z.) Other lists are in place for storms forming in the Pacific Ocean, the Indian Ocean, and across Australasia.

The list of 2019 hurricane names for the North Atlantic — storms which are most likely to impact the U.S. — are as follows: Andrea, Barry, Chantal, Dorian, Erin, Fernand, Gabrielle, Humberto, Imelda, Jerry, Karen, Lorenzo, Melissa, Nestor, Olga, Pablo, Rebekah, Sebastien, Tanya, Van, and Wendy.

The 2019 list will be used again in 2025.

The names on deck for 2020 are: Arthur, Bertha, Cristobal, Dolly, Edouard, Fay, Gonzalo, Hanna, Isaias, Josephine, Kyle, Laura, Marco, Nana, Omar, Paulette, Rene, Sally, Teddy, Vicky, and Wilfred.

If there are more than 21 storms in one season, then the Greek alphabet is used to name additional storms. This method had to be used in 2005, a year in which there were 27 recorded hurricanes, according to the National Hurricane Center.

A storm is typically given a name when it displays a rotating circulation pattern and the wind speed reaches 39 miles per hour.

Why are hurricane names retired?

Only when a hurricane is exceptionally catastrophic is its name retired, according to the National Hurricane Center. During their annual meetings, the WMO makes the call to cut these names from future lists, if necessary.

Names like Katrina (2005), Joaquin (2015), Irma (2017), Maria (2017) and Florence (2018) have been retired. 2005 saw the most names retired in one year with five; 2017 saw four names removed. If a name is removed, the WMO replaces it with a new name. For example, the list of 2011 hurricane names featured Katia as a replacement for Katrina.

It is expected that Dorian will be retired after this year.

This article was originally published on time