00:47 Finally, Some Rest for the Hurricane-Weary Meteorologist Ari Sarsalari explains why you shouldn't let your guard down during this brief break in tropical activity.

At a Glance Florence and Michael will no longer be used as names for an Atlantic tropical storm or hurricane.

Tropical cyclones that are very destructive and/or deadly can be retired from future name lists.

Through 2018, 89 Atlantic hurricane or tropical storm names have been retired.

Florence and Michael were so destructive and deadly during the 2018 Atlantic hurricane season that the World Meteorological Organization's hurricane committee decided this week to retire those names from future Atlantic Basin tropical cyclone name lists.

(MORE: Why the 2018 Hurricane Season Was More Active Than We Predicted)

Atlantic hurricane and tropical storm name lists repeat every six years unless a storm is so destructive and/or deadly that the committee votes to retire that name from future lists. This avoids the use of, say, Katrina, Sandy or Maria to describe a future weak, open-ocean tropical storm.

The names Francine and Milton will replace Florence and Michael, respectively, when the list from 2018 is reused again in 2024.

The name Florence had been in use in the Atlantic Basin since 1953; it had been used nine times, including last year.

Only one other name in the six-year Atlantic name rotation, Dolly, has survived as long as Florence. Dolly will surpass Florence if it's used again in 2024.

(MORE: No Atlantic Hurricane Name Had Been Used Longer Than Florence)

2018 Retired Atlantic Names: Florence and Michael

<img class="styles__noscript__2rw2y" src="https://s.w-x.co/util/image/w/2018_retired_hurricane_names.jpg?v=at&w=485&h=273" srcset="https://s.w-x.co/util/image/w/2018_retired_hurricane_names.jpg?v=at&w=485&h=273 400w, https://s.w-x.co/util/image/w/2018_retired_hurricane_names.jpg?v=ap&w=980&h=551 800w" > Both of 2018's retirees made landfall in the United States.

Florence

Hurricane Florence became a Category 4 hurricane twice while over the Atlantic Ocean but had weakened to a Category 1 before moving ashore near Wrightsville Beach, North Carolina, at 7:15 a.m. EDT Sept. 14 with maximum sustained winds around 90 mph.

But a Category 1 hurricane is still capable of destructive impacts. In Florence's case, it produced catastrophic flooding, wind gusts over 100 mph and a damaging storm surge in the Carolinas.

(MORE: Hurricane Florence Recap)

Florence broke preliminary tropical cyclone rainfall records in the Carolinas, where as much as 35.93 inches of rain was measured near Elizabethtown, North Carolina, and up to 23.63 inches was reported in Loris, South Carolina.

After receiving such extreme amounts of rain, major to record river flooding developed in the Carolinas. Some cities, including Wilmington, North Carolina, were entirely cut off by floodwaters for days.

NOAA estimated the damage from Hurricane Florence totaled about $24 billion, tied with the Western wildfires of summer and fall 2018 as the year's second-costliest U.S. weather disaster .

At least 53 deaths were blamed on Florence in the United States.

Michael

(Editor's note: A post-storm analysis released on April 19, 2019, concluded Michael was a Category 5 hurricane at landfall in the Florida Panhandle.)

Hurricane Michael was a Category 5 hurricane when it made landfall near Mexico Beach, Florida, around 12:30 p.m. CDT Oct. 10 with maximum sustained winds of 160 mph and a minimum central pressure of 919 millibars. That city was decimated.

Michael was the third-most-intense continental U.S. landfall by pressure and tied for fourth-strongest by maximum sustained winds on record. It was also the most-intense Florida Panhandle landfall on record.

(MORE: Hurricane Michael Recap)

In Florida, winds gusted as high as 129 mph at Tyndall Air Force Base, and a 115-mph gust was reported as far inland as Donalsonville, Georgia. Trees were toppled, homes and buildings were damaged and some places were without power for weeks.

The National Hurricane Center's Storm Surge Unit estimated peak storm-surge inundation of 9 to 14 feet above ground likely occurred from Mexico Beach through Apalachee Bay, Florida, a location notorious for storm surge even from less-intense tropical cyclones.

Michael spread a swath of heavy rain from the Florida Panhandle to the mid-Atlantic and southeastern New England. At least one location in seven different states reported at least 5 inches of rain. The heaviest rain fell in North Carolina and Virginia.

More than a dozen tornadoes were also confirmed in association with Michael from Florida to Virginia.

NOAA estimated the damage from Hurricane Michael totaled about $25 billion, ranking as the costliest U.S. weather disaster of 2018 .

At least 49 deaths were blamed on Michael in the U.S.

Retired Name History in the Atlantic Basin

Since the naming of Atlantic tropical cyclones ditched the phonetic alphabet in 1953, 89 Atlantic tropical cyclone names have been retired, including last year's Florence and Michael.

In 2017, the names Harvey, Irma, Maria and Nate were all retired. That was just the fifth time that four or more names had been retired for one Atlantic hurricane season, according to the National Hurricane Center.

The most retirees for a single year was five during the hyperactive 2005 hurricane season. 2017 joined the 2004, 1995 and 1955 seasons with four retired names.

(MORE: 17 Moments We'll Never Forget from the 2017 Atlantic Hurricane Season)

<img class="styles__noscript__2rw2y" src="https://s.w-x.co/util/image/w/four-landfalls_0.jpg?v=at&w=485&h=273" srcset="https://s.w-x.co/util/image/w/four-landfalls_0.jpg?v=at&w=485&h=273 400w, https://s.w-x.co/util/image/w/four-landfalls_0.jpg?v=ap&w=980&h=551 800w" > All four of 2017's retirees made landfall in the United States.

Only 19 seasons have not had a name retired, most recently in 2014. Another 25 seasons, through 2018, have had multiple names removed from future use.

Names beginning with the letter "I" lead the retirees with 11, followed by nine "C" storms and nine "F" storms. Nine of those "I" storms have earned retirement since 2001 alone, including a four-year streak from 2001 through 2004 (Iris, Isidore, Isabel and Ivan, in that order). Wilma in 2005 is the latest-in-the-alphabet retiree.

(MORE: Five-Day Hurricane Track Forecasts Are More Accurate Today Than Two-Day Forecasts 25 Years Ago)

Some names you'll instantly recognize. Others, not so much.

For example, Katrina , Rita and Wilma are the big three you probably remember from 2005. You might have forgotten about Dennis and Stan, however. Did you know Stan may have been more deadly than Katrina ?

Previously retired Atlantic storms weren't all necessarily intense Category 3, 4 or 5 hurricanes. In fact, several were retired because of their deadly flooding in the Caribbean, Mexico, Central America or the U.S.

(MORE: 88 Percent of U.S. Deaths From Hurricanes, Tropical Storms Are From Water, Not Wind)

Some examples of this include 2018's Florence , 2017's Nate , 2013's Ingrid in Mexico, 1996's Hortense in Puerto Rico and 1972's Agnes in the eastern U.S.

Only two Atlantic retirees never attained hurricane status: 2015's Tropical Storm Erika and 2001's Tropical Storm Allison . Damage from Erika's epic flooding may have set Dominica's progress back 20 years , according to the country's prime minister in late-summer 2015.

Allison was a $9 billion storm and one of the worst floods of record in Houston until 2017's Harvey.