Naming mega-storms and hurricanes is a complex process that involves multiple organizations, including the World Meteorological Organization (WMO), the National Oceanic and Atmospheric Administration (NOAA), and individual countries' meteorological agencies.
1. The WMO maintains a list of pre-approved names
The WMO maintains a list of pre-approved names for tropical cyclones, which are assigned in alphabetical order. The list is divided into six regions, each with its own set of names. The regions are:
- North Atlantic Ocean: Names are chosen from a rotating list maintained by the NOAA's National Hurricane Center (NHC). The list includes both male and female names, and it is repeated every six years.
- Eastern North Pacific Ocean: Names are chosen from a rotating list maintained by the NOAA's Central Pacific Hurricane Center (CPHC). The list includes both male and female names, and it is repeated every four years.
- Western North Pacific Ocean: Names are chosen by the Typhoon Committee, a body of the WMO. The committee meets annually to select names for the upcoming season. The list includes names from various cultures in the region.
- South Pacific Ocean: Names are chosen by the Tropical Cyclone Committee for the South Pacific, a body of the WMO. The committee meets annually to select names for the upcoming season. The list includes names from various cultures in the region.
- North Indian Ocean: Names are chosen by the India Meteorological Department (IMD). The IMD maintains a list of names that are used in rotation. The list includes names from various languages spoken in India.
- South-West Indian Ocean: Names are chosen by the Mauritius Meteorological Services (MMS). The MMS maintains a list of names that are used in rotation. The list includes names from various languages spoken in the region.
2. A storm is named when it reaches tropical storm strength
When a tropical depression reaches sustained winds of 39 miles per hour (63 km/h), it is considered to be a tropical storm and is assigned a name. The name is chosen from the pre-approved list for the relevant region.
3. The name of a storm can be retired
The name of a storm can be retired if it causes significant damage or loss of life. The decision to retire a name is made by the WMO. Retired names are not used again for at least 10 years.
Here is a table summarizing the process of naming mega-storms and hurricanes:
| Step | Organization | Action |
|---|---|---|
| 1 | WMO | Maintains a list of pre-approved names |
| 2 | NOAA NHC | Chooses names for storms in the North Atlantic Ocean |
| 3 | NOAA CPHC | Chooses names for storms in the Eastern North Pacific Ocean |
| 4 | Typhoon Committee | Chooses names for storms in the Western North Pacific Ocean |
| 5 | Tropical Cyclone Committee for the South Pacific | Chooses names for storms in the South Pacific Ocean |
| 6 | IMD | Chooses names for storms in the North Indian Ocean |
| 7 | MMS | Chooses names for storms in the South-West Indian Ocean |
| 8 | Storm reaches tropical storm strength | Is assigned a name from the pre-approved list |
| 9 | Storm causes significant damage or loss of life | Name can be retired by the WMO |
