Feeling your scrotum tighten can be caused by excessively cold weather and is a normal occurrence. The scrotum usually has a large amount of smooth muscle as well as skin, which usually changes with the temperature, resulting in a change in volume and size. When the weather is cold, it may cause the scrotum to contract, so it will become tighter, and the volume will be smaller, usually after the heat, the scrotum may appear to become softer or flaccid phenomenon, so it belongs to a normal physiological phenomenon. Normally, we should pay attention to do a good job of local care measures, keep local cleanliness and hygiene, but also to avoid excessive tension, in the cold weather, pay attention to strengthen the warmth.