Weather-lore states that a cat will groom itself just before a storm. Cats groom themselves often and not just before a storm, so it’s hard to justify this. However, there may be a few reasons why this lore could be true. A cat’s hearing is very good and much better than humans, so cats may hear thunder in the distance, long before humans do. During the winter the air inside homes can be dry, and as a cat brushes up against objects it builds up static electricity and can even produce small sparks. By grooming themselves, cats add moisture to their bodies and lessen the amount of static. Therefore, if a cat senses the static in the air before a thunderstorm, it may believe that it needs to start grooming itself to keep itself safe when the storm arrives.