The Newfoundland is a heavy, cuddly dog breed, but their weight and hair can sometimes be a less than ideal combination. The fur is water-resistant and the dog has a long, dense double black coat. The amount and color of the hair combined with the weight, makes the dog extra sensitive to high temperatures and humidity. A dog can only pant and has sweat glands on their noses and paws, none of which are able to keep the dog cool in extreme temperatures and high heat.

Newfoundland's are adaptable, and when living in hot climates for an extended period of time they will shed the undercoat to adjust to the climate conditions. The dog's physical traits make it more likely to develop a sudden heat stroke after periods of rigorous physical exertion. If the dogs body temperature reaches above 102