True humidity does make things feel hotter. The only issue with your assesment is that the UK is not very humid. It's middle of the range for heat/ humidity. It's a temperate climate.
I was about to ask about the humidity; I'd love to be somewhere where the average humidity isn't 70% or higher every day of the year; and this year so far is hot it's like couple weeks from winter and still 25c lmao