Examine the location of the water bowl to determine if there is a reason your cat prefers that area. For example there may be a heating vent, window, or sunny spot that feels good to your cat. If this is a new behavior I would have your cat examined by a veterinarian. This could mean your cat has an increased thirst. There are several diseases that can cause an increased thirst like diabetes, kidney disease, liver disease, and hyperthyroidism. If your veterinarian suspects these diseases screening blood work will be run.
It could be just a habit of his or he could be telling you he wants a clean bowl with fresh water. Cats are very fussy creatures and often it's a guessing game of trial and error to find out what they are trying to convey.