Horseshoe cloud

From Wikipedia the free encyclopedia

A horseshoe cloud in 2016

A horseshoe cloud is a relatively uncommon meteorological phenomenon[1] which manifests as a cloud in the shape of a horseshoe or inverted letter "U".[1][2]

They occur when a horseshoe vortex deforms a cumulus cloud.[2] The clouds are relatively short-lived.[2] Horseshoe vortex clouds are a form of "fair-weather" funnel cloud and are similar to the shear funnel type of funnel cloud.

A March 2018 instance was explained by the United States' National Weather Service:[3][4]

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.

References[edit]

  1. ^ a b "Horseshoe Vortex Cloud (February 07)". Cloud Appreciation Society. Retrieved 12 March 2018.
  2. ^ a b c "An incredibly rare 'horseshoe cloud' was spotted in Nevada and it kept the meme-makers busy". Independent.ie. 12 March 2018. Retrieved 12 March 2018.
  3. ^ @NWSElko (2018-03-12). "As the updraft pushes flattish cumulus clouds up & a horizontal vortex develops from differential updraft speeds..." (Tweet) – via Twitter.
  4. ^ @NWSElko (2018-03-12). "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" (Tweet) – via Twitter.