We take two, three week holidays in Greece every year and I've not found the heat to be a problem. I know what foods to avoid and like
@Sue_Cyprus_ I avoid chips and also rice and pasta etc, but find there are plently of tasty options that won't elevate my BG. I don't test very often as I don't really want to know if the occasional "treat" has pushed up my BG as I doubt if it really matters in the long term, and I'm on holiday and my diabetes can take a back seat for a few days.
A lovely Greek lady we know always presents us with a jar of bitter orange segments in syrup with bergamot and they are just heavenly. It would be impolite to refuse them, so I limit myself to one segment per day, enjoy the anticipation and then the sugary bliss and my wife enjoys seeing the smile spread across my face. Bliss!!!