Roll Cloud
At sea off the coast of Argentina, a cloud appeared that stretched across the horizon, looking like a twisted rope or towel miles long. This type of cloud formation is called a Roll Cloud, a relatively rare type of Arcus cloud. They are completely detached from other cloud features and usually, but not always, seen at sea. The name comes from their appearance of rolling horizontally.
I had to look this one up, as I'd never seen or heard of it before. From many of the comments below, very few others have seen this either.
Roll Cloud
At sea off the coast of Argentina, a cloud appeared that stretched across the horizon, looking like a twisted rope or towel miles long. This type of cloud formation is called a Roll Cloud, a relatively rare type of Arcus cloud. They are completely detached from other cloud features and usually, but not always, seen at sea. The name comes from their appearance of rolling horizontally.
I had to look this one up, as I'd never seen or heard of it before. From many of the comments below, very few others have seen this either.