Strange discoloration around concrete edges comes and goes, why?

[Jwmart]

See photos. Any ideas what this discoloration is around the grove in the concrete?
it seems to come and go.
The picture with very little is from October, the one with the discoloration was taken today on my ring cam.

 

[cowboycasey]

Welcome to TFP

Looks like you have gotten some dirt in the cracks and then it rains... the discoloration should go away as it dries, it may take a while to dry...

 

[Jwmart]

Here’s a better photo of the discoloration up close. I don’t think it’s dirt…
The concrete is not wet either…