It depends on the weather for me as well, but generally I prefer lukewarm showers! I’m very sensitive to temperatures, especially warm/hot temps, so having hot or even too warm showers is uncomfortable for me unless I was freezing beforehand, which I almost never am. Cold temps are my favourite, especially weather-wise, but super cold showers are uncomfortable for me as well. Half of my shower time is me tinkering with the shower so that the water isn’t too hot or cold; getting the right temperature is always a pain for me LOL
My preferred temp is lukewarm that’s teetering on the edge of being cold, but isn’t actually cold. Like, mostly lukewarm, but with a few splashes of coldness in it. Like a cool breeze on a sunny autumn day.