Water
Gray foxes like places where they can get out of the way of predators but also where they have access to the resources they need. Therefore, a water source nearby will be necessary. The foxes will either live in an area where ample rainfall ensures that they have constant water, or where they have access to a reliable lake, stream or river that provides them with water.
Cold
Winter is certainly no barrier to the gray fox. However, gray foxes prefer to stay in areas where winters do not reach the extreme colds borne by their relatives, the arctic foxes. Instead, gray foxes limit their range to as far north as Oregon in the west, Minnesota and Wisconsin in the center of the country and Maine in the east. However, they mostly stay out of Canada where the winters get much colder and harsher than they do in the United States.
Heat
The gray fox is able to tolerate more extreme hot climates than it does cold. This is perhaps due to the fact that it is a mostly nocturnal animal. During the hottest hours of the day in the hottest portions of its habitat, the animal is likely hiding in a cool, dark cave. The habitat of the creature stretches from its range in America down through Mexico and all the way to Venezuela.
Trees
Gray foxes love trees. They tend to make their homes in places where woods still stand, and widespread forest clearing drives the animals out of certain areas. They can even climb trees. As a result, they avoid places with extreme temperatures or extreme dryness where vegetation does not grow well, such as the desert.