So if your cat goes outside, how cold is too cold? Cats are pretty well adapted for cold weather, but when the temperature dips below freezing they are susceptible to hypothermia and frostbite. During periods of cold weather, cats will go looking for a warm place to hunker down. Building an outside shelter for a cat can be an inexpensive and fun project for the family. The shelter should be large enough that the cat can turn around in it, and can be constructed of wood or with plastic bins with holes cut in the side for an entrance. Elevating the structure off the ground and providing warm bedding inside will help ensure your feline friend can retreat to safety from the bitter cold. Also, a safe electric heat source can be added for the most luxurious of shelters. Without a safe haven of warmth, cats will go looking for other warm, covered places such as under the hoods of cars. Here, they are protected from the elements and the engine can put off heat hours after it has been turned off, but if the car is started while they are hidden away, they can be severely injured or even killed.
Read more at Washingtonian.