Weird cloud over Lofoten

[HiThere]

_http://vimeo.com/69347643

 

[Gawan]

Thanks for bringing it up and it was mentioned in two other sources, also when Roy Størkersen seems to be the only source with pictures.

_http://www.nordlys.no/nyheter/article6737656.ece
_http://www.lofotposten.no/lokale_nyheter/article6737470.ece

Impressive roll cloud over Svolvær, Norway

 

[HiThere]

I didn't notice that it was already linked on SOTT, thank you Gawan.

 

[Niall]

I think the high winds, curved shape and heavy rain that came with this cloud make it a wall cloud, the base of a powerful storm.

A roll cloud is truly bizarre in that it is not apparently connected to any larger weather system.

See here for example: http://www.youtube.com/watch?v=i1rdWjrYG5I

Or here: http://www.youtube.com/watch?v=PQkBwtYxEME

(Don't mind the nonsense about UFOs.)

 

[Lycan]

Thanks for the info. Far as clouds goes wall and shell clouds are to me most spectacular ones, especially considering that they form under cumulonimbus clouds, and if we see them, probably we have been already passed through rainstorm or thunderstorm. It is good to understand difference between wall cloud and shell cloud for it can help to see is the storm coming or going away...

Difference between shell and wall cloud: http://www.youtube.com/watch?v=_eZ58IGBfzM

 

[MK Scarlett]

I think the high winds, curved shape and heavy rain that came with this cloud make it a wall cloud, the base of a powerful storm.

A roll cloud is truly bizarre in that it is not apparently connected to any larger weather system.

See here for example: http://www.youtube.com/watch?v=i1rdWjrYG5I

Or here: http://www.youtube.com/watch?v=PQkBwtYxEME

(Don't mind the nonsense about UFOs.)

Thank you for the information, by looking at it, I thought of a "horizontal tornado", but it was just a thought... I had no idea it could exist, so I made some searchs, and actually I found a related news of it:
http://www.redditpics.com/horizontal-tornado-in-albemarle-nc-yesterday-dam,1789564/

And about the Calgary video (first one), I noticed it was two days before the flood of the city: Calgary, Alberta devastated in deluge of biblical proportions

About the Arcus cloud; There are two types: shelf cloud and roll cloud, acording to Wikipedia:

An arcus cloud is a low, horizontal cloud formation. Roll clouds and shelf clouds are the two types of arcus clouds. A shelf cloud is usually associated with the leading edge of thunderstorm outflow; roll clouds are usually formed by outflows of cold air from sea breezes or cold fronts in the absence of thunderstorms.
[...]

And about the shelf cloud:

An extreme example of this phenomenon looks almost like a tornado and is known as a gustnado

And about the roll clouds:

They differ from shelf clouds by being completely detached from other cloud features.

 

[Gawan]

I didn't notice that it was already linked on SOTT, thank you Gawan.

It was made up after your suggestion, so thank you.