{{Short description|Rare type of cumulus cloud}} {{Use mdy dates|date=March 2021}}thumb|A horseshoe cloud in 2016
A '''horseshoe cloud''' is a relatively uncommon meteorological phenomenon<ref name="CAS">{{cite web|title=Horseshoe Vortex Cloud (February 07)|date=January 31, 2007 |url=https://cloudappreciationsociety.org/horseshoe-vortex-cloud-february-07/|publisher=Cloud Appreciation Society|accessdate=March 12, 2018}}</ref> which manifests as a cloud in the shape of a horseshoe or inverted letter "U".<ref name="CAS" /><ref name="IIE">{{cite web |title=An incredibly rare 'horseshoe cloud' was spotted in Nevada and it kept the meme-makers busy |url=https://www.independent.ie/world-news/and-finally/an-incredibly-rare-horseshoe-cloud-was-spotted-in-nevada-and-it-kept-the-mememakers-busy-36691086.html |website=Independent.ie |date=March 12, 2018 |accessdate=March 12, 2018 }}</ref>
They occur when a horseshoe vortex deforms a cumulus cloud.<ref name="IIE" /> The clouds are relatively short-lived<ref name="IIE" /> and is the last stage before one dissipates.<ref name=":0">{{Cite web |last=Baer |first=Stephanie K. |title=People On Twitter Are Freaking Out Over This Rare Type Of Cloud |url=https://www.buzzfeednews.com/article/skbaer/horseshoe-cloud-staple-mustache |access-date=2023-02-02 |website=BuzzFeed News |date=March 10, 2018 |language=en}}</ref> Horseshoe vortex clouds are a form of "fair-weather" funnel cloud and are similar to the shear funnel type of funnel cloud.{{Citation needed|date=February 2023}}
A March 2018 instance was explained by the United States National Weather Service:<ref>{{cite tweet |user=NWSElko |number=972173128800628736 |title=As the updraft pushes flattish cumulus clouds up & a horizontal vortex develops from differential updraft speeds... }}</ref><ref>{{cite tweet |user=NWSElko |number=972173174422036490 |title=As the vortex climbs, it's caught in the faster horizontal winds aloft,& the middle part of the vortex catches the faster speeds with the ends being slower. }}</ref>
{{Quote|As the updraft pushes flattish cumulus clouds up & a horizontal vortex develops from differential updraft speeds... As the vortex climbs, it's caught in the faster horizontal winds aloft, & the middle part of the vortex catches the faster speeds with the ends being slower. }} These clouds do not occur often because all the needed conditions rarely occur together.<ref name=":0" />
== References == {{Commons category}}
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{{Cloud types}}
Category:Cloud types