Consistently inconsistent lag...

For some reason in all of my games in the past month i've had problems with lag. I will bee fine for the first few minutes in the jungle (I'm a jg main) but whenever i go to lane or just interact with an enemy my ping goes from 36 ms to upwards of 500 ms. In 5v5 teamfights it even goes up to 700 sometimes. I know this isn't a problem with my computer because it isn't a framerate problem and i usually play on high graphics and changing it to very low didn't help it at all.