Ask HN: My morning shade disrupted by clouds?

This is quite mundane. Recently, in the mornings, I enjoy shade from a large tree. Within this shade I go about my morning routine.

The sun beats hard this time of year. This morning was cloudy, and as such there was no shade. Of course the sun was still behind the tree top, just shrouded by cloud.

I felt the heat on my skin, and it was obvious I’d get burned before long.

I hadn’t considered this before; is it possible that the blanket of cloud is diffracting the sunlight, and makes the clouds themselves a source of UV, as opposed to a singular source (the sun).

Would this explain why I’m being burned despite the sun being hidden behind the tree canopy (and clouds)?

I never considered that clouds could be negative for seeking shelter from the sun.