eli5: How can one intersection(road) have a dense fog, while the next (relatively close) is completely clear?

Question

eli5: How can one intersection(road) have a dense fog, while the next (relatively close) is completely clear?

In: Earth Science

Answer 1

At its very essence, fog is just a very low cloud.

And if we know anything about clouds it’s that the wispier clouds are higher and the denser clouds are lower.

So essentially, by travelling from one intersection to the next you are actually walking in and out of the thick cloud.

Edit: thanks for the award!