It's been raining for three days straight.
As far as Mary Elric is concerned, this fits her mood perfectly.
She's moping under a tree - one that at least mostly blocks the pouring rain - and listening to the river in the distance. It sounds angry.
(She's angry. They're not being let in to see mom, even though mom's super sick, and Mary knows she's going to die, you don't keep people from seeing someone who's gonna recover easily - )
Which pretty much adds up to the younger Elric sister sulking out in the cold and the rain and contemplating stabbing the out of town doctor with his annoying, condescending smile. The Rockbells were way better doctors. Much.
She's out of easy rocks to throw, so she's left occasionally kicking or hitting the ground. Her knuckles are getting a bit scraped.