I understand it may sound unlikely, however I can't help but notice that several performance issues which had been improved suddenly came back when you re-enabled rain and weather effects.
For example, stuttering - especially the instant a firefight begins - seemed MUCH improved with 0.10.5 (i.e. when there was no rain), but has all of a sudden reappeared with a vengeance as of 0.11 - exactly when rain made its way back into the game... pure coincidence??
The timeline that I've noticed in-game personally also lines up very well with the amount of attention both stuttering and rain have gotten on Reddit lately. So I don't think it's just me.
no its not connected to weather