Spectacular photos of the bizarre ‘roll clouds’ that were spotted over Taiwan yesterday
Taiwan News
Date: 2018/03/06
By: Keoni Everington, Taiwan News, Staff Writer
Roll clouds. (Photo by Facebook user Sophia)
TAIPEI (Taiwan News) — As new cold air front swept into Taiwan from the north, residents of Miaoli County and Taichung City yesterday (March 5) witnessed a rare “roll cloud” formation ominously approach like a scene from an apocalyptic disaster film.
“Roll clouds” are a type of arcus cloud which are rarely seen and are formed from the downdraft of a thunderstorm. They are given their name because they can form almost perfect tubes that appear to be “rolling” on a horizontal axis.
Many residents of Miaoli County and Taichung City witnessed the strange phenomenon and shared their photos on Facebook groups such as 苑裡串起來 and the Facebook page for Cheng Ming-dean (鄭明典), director of the bureau’s Meteorological Research and Development Center.
On his Facebook page, Cheng wrote, “This was a leading cloud of a cold air mass which is has appeared in the form of a long, solitary line referred to as a ‘roll cloud’ with a relatively large width. It is caused by the outflow of cold air, with the heavier cold air lifting the warm and wet air ahead of it, causing the warm and wet water to condense and produce this type of linear cloud.” [FULL STORY]
