A dog's dry and cracked nose may be caused by illness, lack of water or vitamins, a dry environment, etc. You need to check the dog's physical condition first to see if it is sick. If it is not sick but the nose is dry and cracked, then it may be caused by the environment. Or it could be caused by diet. When the weather is dry, you can put a humidifier at home, let your dog eat more vegetables and fruits, and drink more water.