UPDATE:
I found the issue.
*NEW* AI's accuracy/vision is impact my rain intensity.
This 2.6 addition causes problems when you suppress ai - even slightly.
STEPS TO REPRODUCE:
1. Spawn some ai.
2. Have overcast and rain on max
3. Spawn yourself as guy with LMG or have static hmg
4. shoot an entire box at AI - make sure to leave some ai alive to see results
5. observe ai shooting holes all day long 1 foot in front of them. you can walk right up to them and not be hit.
This bug might possibly be a bug with any features of ACE that modify ballistics, but even with advanced ballistics off for non marksmen rifles it still seems to bug out. Maybe an issue with some modifications to AI that ace has?
Is there a way to disable the ai accuracy hit with heavy rain? I can't seem to find where it is in scripts.
EDIT: Found the place where it does the math. It is in the "VCOMAI_FocusedAccuracy.sqf". You can clearly see the weather variable declare then used in the calculations. I ended up taking it out and ai shoot like a charm in the rain - all the other accuracy modifiers still work just fine. Would do a pull request on your git but not sure you check it much @Genesis?