Rare Lightning Travelling from Ground To Clouds In Slow Motion

We had some storms in the Bay Area over the weekend and I captured a slow motion video of a lightning strike, which I'm told is a rare case of lightning starting from the ground and travelling upwards to the clouds. This was recorded on a Sony RX100 Mk VII at 960FPS, ISO 80,000 https://amzn.to/2QdUH0F