FPS drops mid-game for no reason

I am using the same graphics settings as OW1. I never had fps problems in OW1. I never had fps problems in OW2 beta and the first 2 weeks. Since the event was released, my fps keep dropping to 8-12 from 140. In the huge majority of the game, I get my highest set fps (140) and in random moments, even when there is no fight, my fps drops. Anybody else having this issue or how can I fix it? Couldn’t find a fix.

A lot of people are getting sudden fps drops since OW2 and so far there doesn’t seems to be any way to “fix” it.

Based Blizzard. Focus on greedy shop updates but not the actual games problems