In the summer, cats are not afraid of the heat at all, so many people think that they are not afraid of the cold in winter either. In fact, this is a serious misconception. Even though they have a lot of fur, they are still very afraid of the cold.
Cats are relatively thin; compared to dogs, they are clearly "skinny" and don't have much fat to protect them from the cold. A single layer of fur is obviously not enough. When the temperature drops below 0 degrees Celsius, they will feel unwell. 
Most cat illnesses are caused by alternating periods of heat and cold, rather than simply being cold. Cats often stay indoors, and many owners keep the heater on for them. So when cats experience the cold outside, they can't handle it and get sick.
When temperatures drop in winter, owners should prepare a warm and comfortable bed for their cats and be careful not to let them be exposed to cold drafts to avoid them catching a cold.
