Why is Mundo jungle so strong right now? I don't understand.

Ok, if there is anything I have noticed this patch, it's that Mundo is freaking op right now. I'v been playing him top lane and I end up absolutely wrecking face, more than I ever have before. What I don't understand is why people are playing him jungle. Mundo jungle has an extremely high winrate right now, higher than Mundo top. But I just dont understand how. What benifits do you have to play him jungle over playing him top lane. I completely agree it's op right now, but I don't understand how he's suddenly become a jungler.

Now I get that the new masteries benifit Mundo very much, but even with that knowledge he still dominated top lane, at least for me anyway. I get it, Mundo is op right now. But can someone explain to me how he randomly became a jungler? And if so, why play him jungle over playing him top?

Before I end off this bunches of text I want to give a wee bit of backstory. Back at the start of season 5, I was just learning to jungle, and as such I was experimenting was many different champs. I used to play Mundo jungle all the time, though it usually ended with poor results. Granted, I suck. But still, it didn't feel very effective. When champion mastery was introduced, my Dr Mundo mastery level was less than level 2 for for a very long time from how many losses I had. I eventually tried him top lane, and things worked much better. But ever since preseason, I'v been dominating with him top lane, and I am now mastery level 3 with him. But I still don't see why I would go back to playing him jungle, or why I would play him jungle over top lane in the first place.

I know Mundo jungle is supposed to be really strong right now, but I just don't understand the specifics is all.

Whoever is reading this I hope you have a great day, and go whererver you please on the rift~