Dogs are sensitive to sound and movements. They do not understand what is a stormy day with thunder and lighting. Thunder sound can be loud and perceived to be a danger and it can be threatening. Some dogs can be so scare that they shiver and started to salivate heavily. They go into hiding; their heartbeats started to go faster and will not listen to any instruction.
Here are some of the tips to calm your dog down.
Using Behavior Management Control
Do something your dog love, distract them, divert their nervous energy and focus on something else.
Owners should never participate along with the current nervous dog. Do not endorse that it does have something to be afraid.
Pre training session. Owner can play light rainforest music with rain and mild thunder as the background acoustic effects daily to get your doggies conditioned to actual thunder sound.
Managing Home Environment
Give your doggie a safe place to hid in daily. It can be a crate, a bed, and a corner space for comfort. This is to promote a sense of security with the familiar hind out space whenever needs arises.
Blackout the windows, turn on the TV/Radio, can also provide a treat stick/bone to reward your dog being calm.