Please Register or Log in to view the hidden image! This is a rain bomb. Or wet macroburst. http://www.bloomberg.com/news/artic...tornadoes-rain-bombs-are-coming-for-your-town Holy cr*p.
I was sent a picture of that taken through an airplane window by a passenger - the sky around it was clear, more or less (the edges are cut off in that closer view). It reminded me of childhood on the prairie, watching individual thunderheads in the distance start to release rain and lightning.
Google images has lots of nice photos of these. Micro-bursts and macro-burst look like the same thing, distinguished only by diameter. Apparently they are associated with very strong down-drafts that can reach over 100 mph in the macrobursts and over 160 mph in the microbursts. The most visible ones might also contain very strong rain. They look to me to be similar to tornadoes, except without the rotation They can be associated with tornado-type damage on the ground. If one forms above an aircraft, it can force the plane into the ground and make it crash. https://en.wikipedia.org/wiki/Microburst
