List of unnamed tropical cyclones

In order to ease communications and advisories,[1] tropical cyclones are named when, according to the appropriate Regional Specialized Meteorological Center or Tropical Cyclone Warning Center, it has reached tropical storm status. A tropical cyclone with winds of tropical storm intensity or higher goes unnamed when operationally, it is not considered to have met the criteria for naming. Reasons for this include:

• Being missed during a season, usually because of uncertainties in classification in real time. An example of this is the 2005 Azores subtropical storm from the 2005 Atlantic hurricane season.[2]
• Disagreements between warning centre and naming centres over intensity of a cyclone. An example of this is Tropical Storm 06W from the 1995 Pacific typhoon season.[3]
• Formation of a cyclone in an area where no official agency is responsible for naming. An example of this is Tropical Cyclone 29P from the 1996–97 South Pacific cyclone season.[4][5]
• Intentionally left unnamed to avoid confusion. An example of this is the 1991 Perfect Storm from the 1991 Atlantic hurricane season.[6]
• Post-operational upgrading. An example of this is the Unnamed tropical storm from the 1996 Pacific hurricane season.[7]

Only unnamed subtropical cyclones that could have been named are included. This excludes several that existed, but that were unnamed because subtropical cyclones were not named when they existed.

The unnamed hurricane or "Perfect Storm" of 1991

Naming has been used since the 1950 season.

The unnamed tropical storm in 1996

Naming began in 1960. Before 1957, a few systems in the central Pacific basin were given names, generally in an ad hoc manner.

• Unnamed August tropical storm 1962 – This system was upgraded from a tropical depression to a tropical storm after a letter from a ship called the Golden State prompted a re evaluation of the system.[9]
• Unnamed September tropical storm 1962 – This system was upgraded from a tropical depression to a tropical storm after a ship called the Richfield reported sustained winds of 115 km/h (70 mph).[9]
• Unnamed tropical storm – 1963 – This system was not named or numbered as a tropical cyclone operationally, but has been recognized as an Unnamed tropical storm since.[10][11]
• Pacific Northwest hurricane – 1975
• Tropical Storm One-E – 1996 – Was upgraded from a tropical depression to a tropical storm after the United States Coast Guard relayed ship reports to the National Hurricane Center, that suggested the cyclone was a tropical storm.[12]
• Tropical Storm Seven-E – 2020 – Was upgraded from a tropical depression to a tropical storm after European Space Agency’s Advanced Scatterometer (ASCAT) suggested that the cyclone was a tropical storm.[13]

The unnamed tropical storm in 1995

The official practice of tropical cyclone naming started in 1945 within the Western Pacific.[14][15] Due to differences in wind speed criteria between the Japan Meteorological Agency and the Joint Typhoon Warning Center, a system will sometimes be considered a tropical storm by the JTWC but only a depression by the JMA, or vice versa. This results in several apparent unnamed systems. Prior to 2000, the JTWC was responsible for tropical cyclone naming, with the JMA assuming responsibility for naming from 2000 and beyond. Due to this, "unnamed tropical cyclones" that met the JMA's tropical storm criteria but not those of the JTWC prior to 2000 are excluded. Likewise, "unnamed tropical cyclones" that met the JTWC's tropical storm criteria but not those of the JMA from 2000 and beyond are also excluded.

Due to differences in wind speed criteria between the India Meteorological Department and the Joint Typhoon Warning Center, a system will sometimes be considered a tropical storm by the JTWC but only a depression by the IMD. This results in several apparent unnamed systems. Because the IMD is responsible for naming, "unnamed tropical cyclones" that met the JTWC's tropical storm criteria but not those of the IMD are excluded.

Naming has taken place since mid-2003.

There have been no unnamed tropical cyclones using the India Meteorological Department's criteria. One system, 2007's Yemyin, was upgraded after the fact and retroactively named.[16]

The unnamed subtropical storm from the 2006–07 season

Tropical cyclones have been named within this basin since 1960, with any tropical depression or subtropical depression that RSMC La Réunion analyze as having 10-minute sustained windspeeds of at least 65 km/h, 40 mph is named. However unlike other basins RSMC La Réunion do not name tropical depressions, however as they delegate the rights to name tropical cyclones to the Subregional tropical cyclone warning centers in Mauritius or Madagascar depending on whether it is east or west of the 55th meridian east.

• Moderate Tropical Storm F1 – 1998–99
• Subtropical Depression 13 – 1999–2000
• Subtropical Depression 15 – 2000–01

Subtropical Depression 15 – 2006–07

• Tropical Cyclone 01U – 2007–08
• Subtropical Depression 10 – 2009–10
• Subtropical Depression 09 – 2010–11
• Subtropical Depression 13 – 2013–14
• Moderate Tropical Storm 01 – 2018–19

The unnamed cyclone of the 2002–03 season

• Cyclone 5 – 1964–65
• Cyclone 6 – 1964–65
• Cyclone 6 – 1965–66
• Cyclone 9 – 1965–66
• Cyclone 2 – 1967–68
• Cyclone 3 – 1967–68
• Cyclone 11 – 1967–68
• Cyclone 13 – 1967–68
• Cyclone 17 – 1967–68
• Cyclone 15 – 1968–69
• Cyclone 16 – 1968–69
• Cyclone 1 – 1969–70
• Cyclone 7 – 1969–70
• Flores Cyclone - 1972-73[17]
• Cyclone 2 – 1981–82
• Cyclone 6 – 1983–84
• Cyclone 8 – 1995–96
• Cyclone 1 – 2002–03
• Tropical Cyclone 01U – 2007–08 [18]
• Tropical Cyclone 22U – 2016–17[19]

• Unnamed Tropical Cyclone 1971–72 – December 1971
• Unnamed Tropical Cyclone 1971–72 – January 1972
• Unnamed Tropical Cyclone 1973–74 – November 1973
• Unnamed Tropical Cyclone 1976–77 – February 1977 (1)
• Unnamed Tropical Cyclone 1976–77 – February 1977 (2)
• Unnamed Tropical Cyclone 1980–81 – February 1981
• Unnamed Tropical Cyclone 1980–81 – February/March 1981
• Unnamed Tropical Cyclone 1980–81 – March 1981
• Unnamed Tropical Cyclone 1983–84 – February 1984
• Unnamed Tropical Cyclone 1983–84 – March 1984
• Unnamed Tropical Cyclone 1984–85 – December 1985
• Unnamed Tropical Cyclone 1986–87 – March 1987
• Unnamed Tropical Cyclone 1988–89 – February 1989
• Unnamed tropical cyclone 1990–91 – December 1990
• Tropical Cyclone 29P could not be named during February 1997 as it had developed into a tropical cyclone within the subtropic region of the Southern Pacific.[4][5]

Unless otherwise indicated, all storms come from the following datasets from the Regional Specialized Meteorological Center:

• Atlantic: [20]
• Western north Pacific: "RSMC Best Track Data (Text)". Japan Meteorological Agency. Archived from the original on 2013-06-25. Retrieved 2008-06-21.
• Northern Indian, western north Pacific, Southern Hemisphere: "JTWC Tropical Cyclone Best Track Data Site". Joint Typhoon Warning Center. 2007-08-09. Retrieved 2008-05-21.
• Southwestern Indian Ocean: "Untitled". Météo-France. Archived from the original on 2008-04-21. Retrieved 2008-06-21.

• Unisys Weather Data