With the show cancelled, I saw no reason to fight the looming sprinkles or the still soft arena. I walked it, and it's gotten much better.
So I gave everything another day to dry out, and Ransom another day to chill. I went out to see him a few times in the evening, and he was an adorable snuggle-bug. Pretty cool when my horse knows just what I need.
Lesson is scheduled for tonight.