Things that go bump in the night are fairly common. That sudden loud clap of thunder that wakes us from a sound sleep can also get your dog to jump higher than it ever has before and be in the bed with you. Perhaps as the thunder rolls in, your dog heads under the bed or to a corner in the house that isn't usually inhabited. Not uncommon at all.
Fear of loud noises is a response to a potentially threatening situation is one of the protective mechanisms in the animal world. Phobias and fears can start when your dog is a puppy or at any other stage of their life. Finding your dog trembling at your feet during a storm is not unusual. Some dogs hear the noise long before we do and react accordingly.
These fears can occur after a series of events or after one traumatic event. Their fears can be reinforced if the noise occurs frequently. Some dogs just do not tolerate the sounds that cause fear. It is possible that the fear increases with each exposure to the sound. It is also possible that this phobia for loud noises can spread to other sounds other than thunder. You may find your dog frightened by a car backfiring or the sound of fireworks.
Your scared dog will usually seek some kind of human companionship. You are the leader and you are expected to protect him.
It's possible that there are underlying causes for these fears. An examination by your veterinarian may be in order to be sure the dog is healthy. If the problem is too extreme, a behaviorist may need to be consulted.
One of the big problems with dogs who have these fears is that if the storm or other noise occurs when you are away, what will they do? Chances are there will be some destruction in your home, or your dog escapes from your yard. There may be urination or bowel movements that never occur under usual circumstances.
Distraction will help. First you may videotape the occurrence to verify that this is the reason. If it is there are steps that you can take.
When you leave home, keep the radio or television on. The white noise can distract the dog and provide a safe place for him. It's a usual sound and he is likely to seek it out in times of fear. Often the simple techniques will work.
If these tips don't work you may need to take your dog to a veterinarian. Consultation with a behaviorist who will work with you to desensitive your dog may be in order. In extreme cases your veterinarian may prescribe an anti-anxiety medication to help with his fears.
At home if you know a storm is approaching and your dog is mildly anxious, the simple task of redirecting your dogs attention to some other activity will help. Don't pet and coddle, this will reinforce the fear and be counterproductive. Find the dog's favorite toy and play a little game or use some other distraction to keep him busy.