Dog afraid of storms

I worked at our local humane society for a number of years. We had a huge pitbul turned in for rehoming and he was terrified of storms. He would start to howl at the first sign of rain and just tremble all over. I would go into his pen and sit on the floor with this 120lb dog on my lap with his head on my shoulder. We would sit like that until the storm cleared away. I lived just a mile or two from the shelter and if it started to storm in the night, I would get into my car and go over and sit with him to keep him from being so afraid.