Editing Subtropical cyclone (section)

==Characteristics==
[[File:SS One 1979-10-24 1330Z.png|thumb|200px|right|[[1979 Atlantic hurricane season#Subtropical Storm One|Subtropical Cyclone One]] in 1979 is one of only two subtropical cyclones in the north Atlantic to reach hurricane-equivalent intensity.]]

===Intensity===
Subtropical cyclones can have maximum [[wind]]s extending farther from the center than in a purely tropical cyclone and have no [[weather front]]s linking directly to the center of circulation. In the [[Atlantic Ocean|Atlantic]] Basin, the [[United States]] [[National Oceanic and Atmospheric Administration|NOAA]] classifies subtropical cyclones similarly to tropical cyclones, based on maximum sustained surface winds. Those with winds below 18&nbsp;[[Metre per second|m/s]], (65&nbsp;[[Kilometres per hour|km/h]], 35&nbsp;[[knot (unit)|knots]], or 39&nbsp;[[Miles per hour|mph]]) are called subtropical depressions, while those at or above this [[speed]] are referred to as subtropical storms.<ref>National Hurricane Center (2009). [http://www.nhc.noaa.gov/aboutgloss.shtml Glossary of NHC terms.] {{Webarchive|url=https://web.archive.org/web/20120927232946/http://www.nhc.noaa.gov/aboutgloss.shtml |date=2012-09-27 }} Retrieved on 2007-05-05.</ref> Diagrams which depict a [[cyclone]]'s phase depict subtropical cyclones with a shallow warm core and as asymmetric systems, similar to tropical cyclones which have begun the transition to an extratropical cyclone.<ref name="CPS1">{{cite journal| title = A Cyclone Phase Space Derived from Thermal Wind and Thermal Asymmetry| author = Robert E. Hart| journal = Monthly Weather Review| volume = 131| issue = 4| date = April 2003| pages = 585–616| doi = 10.1175/1520-0493(2003)131<0585:ACPSDF>2.0.CO;2|bibcode = 2003MWRv..131..585H | s2cid = 3753455| doi-access = free}}</ref><ref name="NAtlSTCases"/><ref>Robert Hart (2003). [http://www.zamg.ac.at/eumetrain/EUMeTrain2005/ETT/help.html Cyclone Phase Analysis and Forecast: Help Page.] {{Webarchive|url=https://web.archive.org/web/20120528135620/http://www.zamg.ac.at/eumetrain/EUMeTrain2005/ETT/help.html |date=2012-05-28 }} EUMeTrain. Retrieved on 2009-03-01.</ref>

Subtropical cyclones with hurricane-force winds of 33&nbsp;m/s, (119&nbsp;km/h, 64&nbsp;knots, or 74&nbsp;mph) or greater are no longer recognized by the National Hurricane Center. Once a subtropical storm intensifies enough to have hurricane-force winds, it is then automatically assumed to have become a fully tropical hurricane even if it still has subtropical characteristics.<ref name="Wunderground">{{cite web|last1=Masters|first1=Jeff|title=Tropical, subtropical, extratropical?|url=https://www.wunderground.com/hurricane/subtropical.asp|website=Weather Underground|access-date=4 August 2017|archive-date=30 August 2018|archive-url=https://web.archive.org/web/20180830234055/https://www.wunderground.com/hurricane/subtropical.asp|url-status=live}}</ref> Despite this however, prior to the start of modern policies in the Atlantic there were two subtropical cyclones, one in [[1968 Atlantic hurricane season#Subtropical Cyclone One|1968]] and another in [[1979 Atlantic hurricane season#October subtropical cyclone|1979]], that attained hurricane-force winds while subtropical.{{Atlantic hurricane best track}} In addition, one system, [[2000–01 South-West Indian Ocean cyclone season#Subtropical Depression 11|Subtropical Depression 11]] during the [[2000–01 South-West Indian Ocean cyclone season]], was analyzed by the [[Joint Typhoon Warning Center]] (JTWC) to have reached hurricane strength as a subtropical cyclone, but [[Météo-France]] (MFR) only considers it to have been a subtropical depression.<ref>{{cite report|author=Kenneth R. Knapp|author2=Michael C. Kruk|author3=David H. Levinson|author4=Howard J. Diamond|author5=Charles J. Neumann|year=2010|work=The International Best Track Archive for Climate Stewardship (IBTrACS): Unifying tropical cyclone best track data|title=2001 1120002001:HSK2201 (2001171S35037)|publisher=Bulletin of the American Meteorological Society|access-date=2023-07-09|url=http://atms.unca.edu/ibtracs/ibtracs_v03r04/browse-ibtracs/index.php?name=v03r04-2001171S35037|archive-url=https://web.archive.org/web/20160305143826/http://atms.unca.edu/ibtracs/ibtracs_v03r04/browse-ibtracs/index.php?name=v03r04-2001171S35037|archive-date=2016-03-05|url-status=dead}}</ref>

===Examples during the off-season===
[[File:Alberto 2018-05-27 1625Z.jpg|thumb|right|[[Subtropical Storm Alberto]] near Florida on May 27, 2018.]]
Subtropical cyclones are more likely than tropical cyclones to form [[List of off-season Atlantic hurricanes|outside of a region's designated hurricane season]]. Examples during the 21st century in the north Atlantic include:

* Subtropical Storm Ana (which became [[Tropical Storm Ana (2003)|Tropical Storm Ana]]) in late-April of the [[2003 Atlantic hurricane season|2003 hurricane season]].<ref name="HURDAT2">[[National Hurricane Center]] (2017). [http://www.nhc.noaa.gov/data/hurdat/hurdat2-nepac-1949-2016-041317.txt Atlantic Hurricane Database (HURDAT2).] {{Webarchive|url=https://web.archive.org/web/20170712103018/http://www.nhc.noaa.gov/data/hurdat/hurdat2-nepac-1949-2016-041317.txt |date=2017-07-12 }} Retrieved on 2017-04-24.</ref>
* [[Subtropical Storm Andrea (2007)|Subtropical Storm Andrea]] in early-May of the [[2007 Atlantic hurricane season|2007 hurricane season]].<ref name="HURDAT2"/>
* Subtropical Storm Olga (which became [[Tropical Storm Olga (2007)|Tropical Storm Olga]]) in mid-December of the 2007 hurricane season.<ref name="HURDAT2"/>
* Subtropical Storm Beryl (which became [[Tropical Storm Beryl (2012)|Tropical Storm Beryl]]) in late-May of the [[2012 Atlantic hurricane season|2012 hurricane season]].<ref name="HURDAT2"/>
* An [[Unnamed subtropical storm (2013)|unnamed subtropical storm]] in early-December of the [[2013 Atlantic hurricane season|2013 hurricane season]].<ref>{{cite web|title=Post-season action possible in the North Atlantic|last1=Henson|first1=Bob|last2=Masters|first2=Jeff Masters|date=December 6, 2022|url=https://yaleclimateconnections.org/2022/12/post-season-action-possible-in-the-north-atlantic/|publisher=Yale Climate Connections|location=New Haven, Connecticut|access-date=December 9, 2022|archive-date=December 9, 2022|archive-url=https://web.archive.org/web/20221209152021/https://yaleclimateconnections.org/2022/12/post-season-action-possible-in-the-north-atlantic/|url-status=live}}</ref>
* Subtropical Storm Ana (which became [[Tropical Storm Ana (2015)|Tropical Storm Ana]]) in early-May of the [[2015 Atlantic hurricane season|2015 hurricane season]].<ref name="HURDAT2"/>
* Subtropical Storm Alex (which became [[Hurricane Alex (2016)|Hurricane Alex]]) in mid-January of the [[2016 Atlantic hurricane season|2016 hurricane season]].<ref name="HURDAT2"/>
* Subtropical Depression One (which became [[2017 Atlantic hurricane season#Tropical Storm Arlene|Tropical Storm Arlene]]) in mid-April of the [[2017 Atlantic hurricane season|2017 hurricane season]].<ref name="HURDAT2"/>
*Subtropical Storm Alberto (which became [[Tropical Storm Alberto (2018)|Tropical Storm Alberto]]) in late-May of the [[2018 Atlantic hurricane season|2018 hurricane season]].<ref name="HURDAT2"/>
*[[2019 Atlantic hurricane season#Subtropical Storm Andrea|Subtropical Storm Andrea]] in late-May of the [[2019 Atlantic hurricane season|2019 hurricane season]].
*Subtropical Storm Ana (which became [[2021 Atlantic hurricane season#Tropical Storm Ana|Tropical Storm Ana]]) in late-May of the [[2021 Atlantic hurricane season|2021 hurricane season]].
*An [[Unnamed subtropical storm (2023)|unnamed subtropical storm]] in mid-January of the [[2023 Atlantic hurricane season|2023 hurricane season]].