Working (lazily) on a blog post about how the heat is so different in the UK vs the US while I've still got that post-family-visit contrast fresh in my mind, and different ways to cope that I've figured out through trial and error that maybe we can copy from each other and adapt to our own situations
The heat really is Different in the UK. It's not just how the buildings are (pizza ovens) or where the air conditioning is (it isn't) or whether the people have acclimatized (we have, it doesn't take generations, a week or two will do it), it really is a whole different physics
The sun is hotter and brighter and the shade is cooler. There's so much less pollution, the sun's infrared isn't getting absorbed into all the shit floating around in the air, it's coming straight at you, so you'll take a jacket with you in the morning and it'll be on and off and on and off all day long. You'll move into the shadow of a building and get goosebumps. You'll stroke someone's hair in the sun and it'll be hot beneath your fingers. The light is different, more contrasty, you can see much further, there's not as much splitting and reflection and refraction and whatnot so the sunny places are brighter and the shadows are darker, and you really really feel that sun, and it absolutely blasts everything the light touches.
In the USA the air gets hot, in the UK the buildings get hot. It's different heat and it feels different and it affects people differently and it needs different ways to deal with it, it's toaster vs rice cooker, it's convection vs radiation, it's Different Heat, and it needs different approaches to deal with it