I just saw this in Northern Germany at 8 pm. At first, i photographed the clouds that look like waves seen from below (last image attached). Then: it developed within like 5-8 min while I was inside Lidl, then I came out and saw that damn thing. It spans from left to right approximately 20-30 km. The air was very warm, humid and no wind whatsoever, none. Then this thing came from west to east, reached me within like ~2 minutes and then suddenly strong winds started, like shaking tree level strong. It rained, and lightning and thunder occasionally, I counted seconds between lighting and thunder and estimated the clouds were ~3 km up. Literally thought "alright guess this is how the biblical apocalypse starts". Never seen something even remotely resembling this. submitted by /u/SwingingHumanBeing [link] [comments]