That's true - I don't think the temperature here in the UK has risen above 80 degrees in the last couple of years (and even when it has got that high, it's only lasted for a couple of days and then it's gone back to cloud/wind/rain again). We had about a week or so of 90+ degrees in July 2006 and August 2003, but the average summer temperature in both of those years was still only about 70 degrees.
There's a reason millions of Brits flood to the US and continental Europe/the Mediterranean each summer... it's the only way we can experience guaranteed sunshine and warm weather .
I agree that there is usually no need for an air conditioner as the UK mostly does not get that hot. Window-opening seems to take care of most needs during the warm months.
I would point out, though, that even though the UK is a relatively small landmass, weather and temperatures can vary depending on where you are, and it can't really be generalized. For example, last summer I arrived to a part of greater London that was actually pretty damn warm, warm enought that I was still wearing my hot Texas summer clothing quite comfortably, and felt that it had been quite warm indeed where I was. I am not 100% certain but I think my area at the time did in fact see some over-80s temps. When I posted about this on this board at the time, people in, say, Yorkshire were contradicting me and saying they hadn't had a chance to wear light clothing and had not had warm temperatures. So evidently, in my spot of the world I felt it had been a "good summer" with comfortably nice temperatures, while other had quite a different opinion.
It isn't just all one flat experience of the same weather and same temps from Land's End to John O'Groats.....
The southern part in general, of the landmass, seems to enjoy slightly warmer conditions than the north and Scotland, so it's a kind of "your mileage may vary" kinda deal in the UK, for weather. I was looking up flats in various areas, and I was looking into a town/region in Essex where, oddly, the info on it said that because of certain geographical peculiarities, it enjoyed milder and more stable temperatures than other places even close by. Freaky. Just to illustrate, you do get variations even though this seems like such a small bit of land in the world.
But even so, having digressed a little.......yep, you
still don't need an air conditioner no matter where you will be living, really.