It can be very frightening for your dog to experience a thunderstorm. You will notice different behaviour from your dog and it could be anything from barking, whimpering, sniffing the air excitedly or hiding somewhere.
This is not the time to coddle your dog, instead it’s an opportunity to get your dog used to these situations. Classic conditioning is the behaviour modification method I use in most of these situations.
We are currently boarding Addie, a 9-year-old Coon Hound that is frightened by the sound of thunder. Last night we experienced some thunderstorms and Addie showed signs of anxiety, she went into a large crate we keep in the family room without prompting, staying in there while the door was open. When the thunder starts I condition her by feeding her kibble until the sound stops, when the thunder starts again I start feeding again. It will take more thunderstorms, but she is on her way to feeling less stressed in these situations.