Editing Natural disaster (section)

==== Tornadoes ====
[[File:Shoal Creek Valley Alabama Tornado April 27, 2011.jpg|thumb|right|A [[2011 Shoal Creek Valley–Ohatchee tornado|killer tornado in Alabama]] photographed during the [[2011 Super Outbreak]], the most intense tornado outbreak on record.]]
{{see also|List of tornadoes and tornado outbreaks}}

A [[tornado]] is a violent and dangerous rotating column of air that is in contact with both the surface of the Earth and a [[cumulonimbus cloud]], or, in rare cases, the base of a [[cumulus cloud]]. It is also referred to as a ''twister'' or a ''cyclone'',<ref>{{cite web |title=Definition of CYCLONE |url=https://www.merriam-webster.com/dictionary/cyclone |url-status=live |archive-url=https://web.archive.org/web/20210105190603/https://www.merriam-webster.com/dictionary/cyclone |archive-date=2021-01-05 |access-date=2020-12-29 |publisher=Merriam-Webster}}</ref> although the word [[cyclone]] is used in meteorology in a wider sense to refer to any closed [[low pressure area|low pressure]] circulation. Tornadoes come in many shapes and sizes but typically take the form of a visible [[funnel cloud|condensation funnel]], the narrow end of which touches the Earth and is often encircled by a cloud of [[debris]] and [[dust]]. Tornadoes can occur one at a time, or can occur in large [[tornado outbreak]]s associated with [[supercell]]s or in other large areas of thunderstorm development.

Most tornadoes have wind speeds of less than {{convert|110|mph|km/h|sigfig=2|order=flip|abbr=on}}, are approximately {{convert|250|ft|m|round=5|order=flip|abbr=on}} across, and travel a few kilometers before dissipating. The [[Tornado records#Largest and most powerful tornadoes|most extreme tornadoes]] can attain wind speeds of more than {{convert|300|mph|km/h|order=flip|abbr=on}}, attain a width exceeding {{convert|2|mi|km|0|order=flip|abbr=on}} across, and stay on the ground for perhaps more than {{convert|100|km|mi|sigfig=1|abbr=on}}.<ref name="fastest wind">{{cite web |author=Wurman, Joshua |date=2008-08-29 |title=Doppler on Wheels |url=http://cswr.org/dow/DOW.htm |url-status=dead |archive-url=https://web.archive.org/web/20070205124033/http://www.cswr.org/dow/dow.htm |archive-date=2007-02-05 |access-date=2009-12-13 |publisher=Center for Severe Weather Research}}</ref><ref name="widest tornado">{{cite web |date=2005-10-02 |title=Hallam Nebraska Tornado |url=http://www.crh.noaa.gov/oax/archive/hallam/hallam.php |url-status=live |archive-url=https://web.archive.org/web/20140820095200/http://www.crh.noaa.gov/oax/archive/hallam/hallam.php |archive-date=2014-08-20 |access-date=2009-11-15 |work=[[National Weather Service]] |publisher=[[National Oceanic and Atmospheric Administration]]}}</ref><ref name="SPC FAQ">{{cite web |author=Roger Edwards |date=2006-04-04 |title=The Online Tornado FAQ |url=http://www.spc.ncep.noaa.gov/faq/tornado/ |url-status=dead |archive-url=https://web.archive.org/web/20060929185156/http://www.spc.ncep.noaa.gov/faq/tornado/ |archive-date=2006-09-29 |access-date=2006-09-08 |work=[[National Weather Service]] |publisher=[[National Oceanic and Atmospheric Administration]]}}</ref>