I had something similar happen to me last month.
I was just enjoying my vacation as you do... a good stroll around the stores and the odd coffee here and there to quench the thirst.
It's Mid-September, in England... how hot could it possibly get, I thought to myself. Well, it did get hot enough for me to actually wear a dress that I had packed and taken with me with zero intention of wearing publicly (I had no shoes to go with it).
After the first part of the vacation concluded, we moved to a more accessible hotel and I felt safe enough to take a bath/shower while I was working (I worked 24/7 the entire vacation).
After I finished in the tub, I'm preparing to step out when I caught a glimpse of my forehead in the mirror. There's about 1cm of my usual white skin - before I noticed the familiar redness of sunburn.
To this day, I still swear up and down that it wasn't hot enough for me to get a sunburn... though my forehead told a different story.
