Lighting conductor

Having led us up a smooth, snow-covered crest, he stood facing the North and the night. As the first green lights began to play, just above the horizon, he waved his hand towards them. A curtain of red light was greeted with a swooping motion with both arms. Each new effect had a gesture in response.

Except...

Except, I wasn't sure that the gestures didn't precede their corresponding flashes and waves of light. Was he reacting to the show? Or conducting it?