I've always struggled with heat and 25 is my limit, beyond which I'm headachey, dizzy and feel ill.
I've spent the last week housebound and confined to 2 rooms which have thermal film on the windows, heat-reflective blinds, heat-blocking curtains, ceiling fans and air-con. It's still 29 deg indoors and barely cools down at night. We've had power cuts due to fuses melting/arcing (apparently).
Out of curiosity, I popped a thermometer in the garden an hour ago and it's 48 deg. I can't stand it.