Understanding I may not be on the fat part of bell curve when it comes to outdoor activities, but I've literally never experienced that feeling. Working with my top off means I'll spend the evening peeling blisters off my skin. Doesn't make my feeling or your feeling valid or invalid; but there's at best a tenuous line between how good something feels and how good it holistically is :-/
Check a yearly UV index for your area. There are times of day that are completely safe for your skin type; but typically those times are quite early / late, like before 8am and after 4pm. UV tends to rise quite sharply in the morning, so while it might be a 2 or 3 at 8am it could be 5 or 6 at 9am (enough to burn your skin type).