Hurricane season: The terminology you need to know

As the 2025 hurricane season approaches, it is crucial to become familiar with the season’s terminology and what everything means as soon as advisories are issued.

Knowing what basic critical terms mean could save you lots of time (and worries) and avoid confusion in hyped messages.

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Official advisories come from the National Hurricane Center and your local National Weather Service Office.

Florida is split into six regions: South Florida, East Central Florida, West Central Florida, North Florida, and the Panhandle. Five offices are situated throughout Florida, and one handles the extreme western portion of the Panhandle in Mobile, Alabama.

The difference between a watch and a warning.

Crucial terms to know

Watch: A tropical storm or hurricane watch is issued when sustained winds (39 to 73 mph for a tropical storm or at least 74 mph for a hurricane) are possible within 48 hours. These winds may be accompanied by storm surge, coastal flooding and/or river flooding. The “watch” does not mean that tropical storm/hurricane conditions will occur. It only means that these conditions are possible.

Warning: A tropical storm or hurricane warning is issued when sustained winds (of 39 to 73 mph for a tropical storm or at least 74 mph for a hurricane) are expected in 36 hours or less. When a warning is issued, it means that conditions are imminent.
Storm surge: The abnormal rise in seawater level during a storm, measured as the height of the water above the normal predicted astronomical tide. The surge is caused primarily by a storm’s winds pushing water onshore.
Tropical disturbance: An area of organized thunderstorm activity 100 to 300 miles in diameter that maintains its identity for 24 hours or more and is in the lower levels of the atmosphere (surface). Suppose the disturbance acquires a spin and winds of at least 30 mph. It is now called a tropical depression. It forms over waters of at least 80 degrees.
Tropical depression: A cluster of storms trying to organize and produce maximum winds below 39 mph.

Tropical Depression formed on September 14, 2022 which later would become Fiona. — A tropical depression formed Sept. 14, 2022. It later became Hurricane Fiona.

Tropical storm: When the cluster of storms has acquired better organization, there is some circulation near the center, and the winds reach between 39 and 73 mph. At this point, the storm will also receive a name. Water temperatures under the system are usually above 80 degrees.
Subtropical storm: These storms develop in the same way as tropical storms, over waters with a temperature of at least 70 degrees. They also tend to have a closed circulation, but the difference is in their organization. Usually, their maximum winds occur far from their center (at more than 60 nautical miles from it) and tend to be messy, meaning not symmetric. Its rains are usually shifted to the side.
Hurricane: Once a tropical storm strengthens, and its maximum sustained winds reach at least 74 mph, it becomes a hurricane. Hurricanes are split further into categories based on wind speeds.
- Category 1: 74-95 mph.
- Category 2: 96-110 mph.
- Category 3: 111-129 mph.
- Category 4: 130-156 mph.
- Category 5: above 157 mph.
Major hurricane: Any hurricane of Category 3, 4 or 5.

How do storms get named?

A tropical low-pressure system must be at least a tropical storm (or subtropical) to receive an official name. The names come from a list that rotates every six years. They could be Spanish, French or American. This is done intentionally to serve better this region of the world, where hurricanes have an impact.

Even-numbered years start with male names, and odd-numbered years start with female names. It wasn’t always like this.

Before satellites existed, storms usually received their names depending on the regions they affected, saints or holidays. The names were generally given after the event.

In 1953, storms started getting official names, only female names. By 1979, the lists were updated, alternating male names were added, and the six lists were officially implemented.

Names for the 2025 Atlantic Hurricane Season.

You will no longer see Greek letters if we use all the names on the list in a season.

The National Hurricane Center, along with the World Meteorological Organization, which handles the adding and retiring of names, has a supplemental list of names that will kick in any year all names are used. This supplemental list of names will be used every year. If one name is retired from the list due to the storm being catastrophic and costly and meeting the retirement criteria, it would be replaced like any other storm retired from the rotating lists.

Names retired

Only 19 seasons have gone by without a name retired since 1954. The most recent year was 2014, and no names were retired.