That didn't sound like upward lightning to me, but I'll take your word for it. I've been totally blind since birth, and I love studying the weather. So when I hear lightning, especially upward lightning, there's usually a tone resonance that drops as the lightning streams upward. A great example of this sound is when you set off a large canister rocket, you'll usually hear a tone that actually drops as the rocket is propelled upwards. The same thing applies with really good fireworks that sparkle or a lovely pyrotechnical fountain that projects 15-20 feet up in the air. Even airplanes make that sound, especially fighter jets when the pilot uses the afterburners and smoke. I hope you've got more videos coming.

what a joke!