Why does Thunder n Lighting make my dog jump into the Bathtub? She never use to be like this until a year ago we moved into a new place. Does anyone know how I could calm her down when it rains?

Medication from the vet can help. Giving her a crate to be a safe den to retreat to, would too. You don't have to shut the door. The dog may be happier in its den than loose in the house. It relaxes, it feels safe in its den. It rests, the body slows down reducing the need for water and relieving its self. Dogs that have been crated all along do very well. Many of them will rest in their crates even when the door is open. I think the plastic ones give the dog more of a safe, enclosed den feeling. Metal ones can be put in a corner or covered with something the dog can't pull in and chew. Select a crate just big enough for the full grown dog to stretch out in.

A dog that has not been crated since it was little, may take some work.
Start just putting its toys and treats in the crate. Praise it for going
in. Feed it in the crate. This is also an easy way to maintain order at
Feeding time for more than one dog.