Which condition is typically exacerbated by cold weather and occurs on the fingers and toes?

Raynaud's phenomenon is characterized by episodic vasospasm in the small blood vessels of the fingers and toes, leading to color changes, numbness, and discomfort typically triggered by cold exposure or emotional stress. In colder weather, these symptoms can worsen significantly as the body attempts to conserve heat by constricting blood vessels, causing reduced blood flow to the extremities. This results in the classic tri-color change of pallor, cyanosis, and finally erythema as blood flow returns.

In contrast, cold urticaria is an allergic skin reaction characterized by hives or welts upon exposure to cold stimuli, but it does not result from vasospasm and is not limited to the fingers and toes. Chilblains, while also associated with cold, occur due to prolonged exposure to non-freezing cold and typically affect the fingers and toes along with swelling and itching. Frostbite is a more severe condition resulting from freezing of the skin and underlying tissues, which can occur with prolonged exposure to extreme cold but doesn't specifically refer to the phenomenon of vasospasm.