Anyone else getting unexplained Lag?

I never ever ever lag in game, but I just had a game where I froze for seconds at a time. My ping was 81 and my net speed was great. Nothing was interacting with my league but I would just freeze for up to 5 seconds at a time. The rest of the game would be fine but I would just stop. My lane opponent got a free lead off it so I'm pissed.