Hello,

a few days ago there was a thunderstorm here. Because it was an
interesting view, I have tried to take some photos and videos of it.
And, accidentally, something strange has been recorded on the video.
It looks like an explosion under one of clouds. I'm curious what it
was. I have never seen a ball lightning – maybe it was one of them?

Here is the video (mpeg): http://tinyurl.com/ftrl
Single frames from this video (JPGs archived in zip):
http://tinyurl.com/ftro
A photo taken one day later (JPG): http://tinyurl.com/g1cm

Regards
Piotr