Dressing for the weather - basic question

[shootingstar]

Past week, I've started to wear long walking shorts for cycling now. It's been starting off at 50 degrees F and going up. My knee length cycling shorts are busted..

But interestingly I know every cycling season, by fall, my bare legs become accustomed to cycling under more cooler temperatures. So by then, I'm cycling in shorts at 42 degrees F or so. Whereas right now for spring, I find that abit too cold.

But outside, we see many joggers and cyclists in their shorts right now.