I have an area underneath an egress window in the basement where the caulking has shrunk and the bare wood is exposed (see pictures below). I thought about backer rod and caulking the top and bottom, but the angle makes it impossible to caulk the top. Then it occurred to me to perhaps use the Great Stuff Window and Door expanding foam in the gap to seal it so water doesn't get to the wood.
Is there a better solution for this? I like the idea of foam as it expands to all the cracks, but not sure if there is a better solution out there. Pictures below...