Let’s zoom in on the interesting bit.

zooms in on Edinburgh, Dublin and Reykjavik

My gut feeling tells me high altitude southern cities are stable around “room temperature” (like Mexico City and La Paz) but if one doesn’t mind 30C for a few weeks, then of course a lot more cities in the Mediterranean, California, Australia etc are also in play.

I take it the person writing the article prefers anything, including a constant drab rain, to ever having -15C or +30C.