Editing Firestorm (section)

==Mechanism==
{{see also|Thermal column}}
[[File:Firestorm thermal column.svg|thumb|right|Firestorm schematic: (1) fire, (2) updraft, (3) strong gusty winds, (A) [[pyrocumulonimbus cloud]]]] [[File:Pyrocumulonimbus cloud over Hiroshima, near local noon. Aug 6 1945.jpg|thumb|right|A firestorm after the bombing of Hiroshima]]
A firestorm is created as a result of the [[stack effect]] as the heat of the original fire draws in more and more of the surrounding air. This draft can be quickly increased if a low-level [[jet stream]] exists over or near the fire. As the updraft mushrooms, strong inwardly-directed gusty winds develop around the fire, supplying it with additional air. This would seem to prevent the firestorm from spreading on the wind, but the tremendous turbulence created may also cause the strong surface inflow winds to change direction erratically. Firestorms resulting from the [[bombardment]] of [[urban areas]] in the Second World War were generally confined to the areas initially seeded with incendiary devices, and the firestorm did not appreciably spread outward.<ref name="AD673703 1961, pg 8 & 9">{{cite web|url=http://www.dtic.mil/cgi-bin/GetTRDoc?AD=AD673703&Location=U2&doc=GetTRDoc.pdf|title=Problems of fire in Nuclear Warfare 1961|pages=8 & 9| website=Dtic.mil|access-date=2016-05-11|url-status=dead|archive-url=https://web.archive.org/web/20130218040912/http://www.dtic.mil/cgi-bin/GetTRDoc?AD=AD673703&Location=U2&doc=GetTRDoc.pdf|archive-date=18 February 2013}}</ref> 

A firestorm may also develop into a [[mesocyclone]] and induce true tornadoes/[[fire whirls]]. This occurred with the 2002 Durango fire,{{sfn|Weaver|Biko|2002}} and probably with the much greater [[Peshtigo Fire]].<ref name="Denise Gess">{{harvnb|Gess|Lutz|2003|p=234}}</ref><ref>{{cite web |last=Hemphill |first=Stephanie |title=Peshtigo: A Tornado of Fire Revisited |url=http://news.minnesota.publicradio.org/features/200211/27_hemphills_peshtigofire/|website=Minnesota Public Radio|access-date=22 July 2015|date=27 November 2002|quote=The town was at the center of a tornado of flame. The fire was coming from all directions at once, and the winds were roaring at 100 mph.}}</ref> The greater draft of a firestorm draws in greater quantities of [[oxygen]], which significantly increases combustion, thereby also substantially increasing the production of heat. The intense heat of a firestorm manifests largely as radiated heat ([[infrared]] radiation), which may ignite flammable material at a distance ahead of the fire itself.<ref>{{cite web|author=James Killus |url=http://unintentional-irony.blogspot.no/2007/08/firestorms.html |title=Unintentional Irony: Firestorms |website=Unintentional-irony.blogspot.no |date=16 August 2007 |access-date=11 May 2016}}</ref><ref>{{cite web |author=Chris Cavanagh |url=http://holbert.faculty.asu.edu/eee460/cjc/Thermal_Radiation_Damage.html |title=Thermal Radiation Damage |website=Holbert.faculty.asu.edu |access-date=11 May 2016 |archive-date=16 March 2018 |archive-url=https://web.archive.org/web/20180316085432/http://holbert.faculty.asu.edu/eee460/cjc/Thermal_Radiation_Damage.html |url-status=dead }}</ref>{{failed verification|date=May 2013}} This also serves to expand the area and the intensity of the firestorm.{{failed verification|date=May 2013}} Violent, erratic wind drafts suck movables into the fire and as is observed with all intense conflagrations, radiated heat from the fire can melt some metals, glass, and turn street [[Asphalt concrete|tarmac]] into flammable hot liquid. The very high temperatures ignite anything that might possibly burn, until the firestorm runs low on fuel.

A firestorm does not appreciably ignite material at a distance ahead of itself; more accurately, the heat desiccates those materials and makes them more vulnerable to ignition by embers or firebrands, increasing the rate of fire spotting. During the formation of a firestorm many fires merge to form a single convective column of hot gases rising from the burning area and strong, fire-induced, radial (inwardly directed) winds are associated with the convective column. Thus the fire front is essentially stationary and the outward spread of fire is prevented by the in-rushing wind.{{sfn|Glasstone|Dolan|1977|pp=299, 300, ¶ 7.58}}