If you weren't awake at 6:15 here in Chicago, that's probably why you woke up. There are only two places on the planet that storms and thunderclaps like that happen, here, and on the steppes of Russia. When the Europeans come here to visit, they are scared witless by our thunderstorms. What they would call a storm, we Midwesterners would merely dismiss as 'heat lightning'. To my nephews and friends in Australia: Yeah, yeah, we've heard your songs about thunder. You have no idea.
Imagine a truck filled with oxygen tanks and another, with a load of lithium and magnesium for the light, meeting head on. Then, two seconds later, the trucks behind them with the 2nd loads coming into the mess.
Matt