Vagina??? Vulva??? 
Let's just call it a vajulva! 
Anyway, I don't get a sweaty foof at all, but I do get annoying sweaty underboobs! And I wear shorts to my knees so don't get chuff chuff with the thighs. I am not particularly large - maybe 2 stone overweight, and a size 14-16, so don't suffer too badly with the heat and bits 'rubbing.' I think I get sweaty underboobs because I have quite big boobs.
Being on your period when it's really hot is a real treat isn't it?! 
@LakieLady
I don't notice the underboob sweat until I take my bra off in the evening (usually about 30 seconds after I get in the door). It's so warm and damp inside my bra, I'm thinking about planting mustard & cress in there.
What I do notice is the river of sweat that runs down my spine, and then becomes a torrent when it reaches the crack of my arse. I don't seem to get sweaty groin or chub rub though, despite being a fat old mare.
😂😂😂
@GladAllOver
Not wishing to divert the discussion, but does anyone else find that the warm weather increases their libido?
When DH comes home and steps out of the shower I just want to jump on him. He hasn't complained yet, fortunately. 
Like @RiverTam I am the opposite, and I don't feel like being touched at ALL when it's super hot and sticky.