I really hate it when we have to wear formal dress to office. I feel like a marketing executive. My code stares at me with suspicious looks.

Workplace requires formal dress code. In Italy, in July, with up to 30C (90F) outside. And August is going to be worse.
I have to take a train + walk 10 minutes to get there. And I sweat, like, a lot. I frigging DRIP. It gets embarrassing, and I think I was close to passing out a couple of times in the last few days.
I really don't know how to mitigate the damage. Suggestions?