Down to a 37 here on the MetO raw, and that seems reasonable to me. It's 23.1 out there (22.4 dewpoint) and feels very oppressive already - indoors, thanks to leaving the portable aircon running overnight, it's 23C down and 27C up (my bedroom was cooler but at midnight I switched to piping the cold air downstairs instead). It will have been a very uncomfortable night, even for heat fans, and tonight will be even worse...
Norwich is sporting a 39 on today's MetO raw, and if it's not north Kent it'll be East Anglia that records the highest temperatures today, and indeed I still expect the highest of the whole heatwave today.
Good luck to everyone in the heatwave zone, especially those who've avoided the worst of it until now!