Replying to Is it possible to ski free at hood early summmer?

Recently I saw a video where these guys just hiked right up the mountain and started skiing. It may have been after hours but I was still wondering if it's possible during early summer to just hike up the mountain, get some skiing in and not get caught while doing this. Sorry that I don't know much about hood, I just really want to ski in the summer, so that would be awesome if somebody could help me out!