Is the 'herald patch' quite common in winter and does it go away on its own?

Herald patch: A herald patch is a 5-7 cm salmon colored patch on the skin seen with pityriasis rosea (pr). It is presumed this is a viral infection from human herpes virus 7. Pr is a harmless (unless you are pregnant) skin rash that causes small, itchy spots on the trunk, arms, and legs that usually lasts 4-6 weeks but rarely for months. The rash takes the shape of a christmas tree on the back. May be itch.

Pityriasis Rosea: Pityriasis rosea is a skin rash that usually begins as one large circular or oval spot on your chest, abdomen or back. Called a herald patch, this initial spot can be up to 4 inches (10 centimeters) across. The herald patch is typically followed by a distinctive pattern of similar but smaller lesions that sweep out from the middle of your body in a shape that resembles drooping pine-tree branches.