Causes:

Storm phobias are one of the most common behavioral problems dog owners face but their cause is not entirely clear. Behaviorists are not yet sure what part of the storm frightens dogs most, whether they're reacting to lightning flashes, the sound of thunder, wind blowing around the house or the sound of rain hitting the roof. Some dogs even start to pace and whine half an hour or more before a storm. They may be reacting to a sudden drop in air pressure, sounds of thunder that we can’t hear yet, or the electrical charge of the air.

Nature or nurture?

An article in the July/August 2001 issue of the Journal of the American Animal Hospital Association describes an Internet survey of the owners of storm-phobic dogs. The authors discovered that some breeds may be predisposed to a fear of storms. Herding dogs, such as collies and German shepherds and hounds, such as beagles and basset hounds, seem to be more likely to develop a storm phobia than other dogs. The phobia is also common in sporting and working breeds. The study suggests that this tendency may be explained in terms of the dogs' genetics. For example, herding dogs have been bred to react quickly to stimuli, but to not respond to their strong predatory drive. This means they have to suppress their natural tendencies which can lead to high levels of anxiety. It is speculated that herding dogs have a strong reaction to the startling noises and flashes of a storm, but they repress any aggressive response to it, causing anxiety.

The JAAHA study also showed that rescued dogs--dogs adopted from shelters or rescue organizations--may also be more likely to develop storm phobias. The article suggested that these dogs are more likely to have had less socialization or unpleasant, scary experiences prior to being adopted. They may have been abused or abandoned by a former owner or they may not have been exposed to a wide variety of sights and sounds. These kinds of early-life experiences can make dogs more anxious and prone to all kinds of phobias.