Rainy days

My dog and I are pretty set in our ways, and our morning routine doesn’t change much.
After I’m dressed and ready to leave for work, Sensi and I walk down the hallway and make a right at the foyer.
I open the door, hook Sensi to the chain and send him outside to take care of his business.
I make a sandwich for lunch while he’s outside, and when I’m done he’s waiting by the door. As soon as I unclasp him from the chain, he runs full-speed toward the laundry room and waits eagerly by his food bowl.
After I feed him, I make myself coffee while he eats. Then he watches me with big sad eyes as I put my coat on and walk toward the door.
“You be a good boy today,” I say, patting him on the head before leaving the house.
Today was different though, and I knew it would be as soon as I saw Sensi staring out the bedroom window.
It was the noise of the rain that prompted him to jump down from the bed and look outside. He didn’t like what he saw.
Sure enough, as we exited the bedroom and got to the front door, I doubted he would go outside.
“Are you gonna give it a go?” I asked him, hooking the chain to his collar.
He peeked his head out the door and immediately backed up, stepping further into the house and looking at me with this, “No way am I going out there,” expression.
I unhooked his chain. There’s no point in forcing him. He won’t step off the porch when it’s raining.
So he had breakfast instead, and apparently, the bathroom wasn’t going to wait. He begged to go outside.
I shook my head at him, “It’s still raining outside pal.” But I let him out anyhow.
While I was watching, he didn’t step off the porch. He must’ve ventured into the rain at some point though, because when he came back inside, he was wet and absolutely full of piss and vinegar — throwing himself on the carpet and rolling around violently, trying to get himself dry.
Is this normal or am I the only dog owner out there whose dog hates the rain so much?