Not a cloud expert, but with a qualified guess I would say what you saw was a Steemus Cumulus.
That is, a cloud in honor of steem.
Seriously though, maybe semi-seriously, in the first picture we can see two bright white stripes. If you add another stripe and turn it vertically you will have the SteemIt logo... aka. Steemit Cumulus! 😃
lol, I'll take it, best explanation so far. :D
Just don't quote me on the facts. ;)
I'm heading up north tomorrow so I hope I will find that kind of weather.
In Germany it has literally rained non-stop for the last day.
Trevlig kväll!!