Runny nose (rhinorrhea) in cold weather is actually a normal response of your body to the cold weather. The cold, dry air stimulates the mucus glands in the nose to produce extra mucus, which insulates and protects the sensitive lining of the nose. Unfortunately there is no treatment of this normal response, other than to protect oneself from the cold air when going outside. Decongestants and other similar medications may have an effect, but they are not meant to used long term for a problem not related to respiratory virus. It might be worthwhile talking to your doctor
to make sure there is not another treatable condition which is causing your runny nose. For example nasal allergies, called allergic rhinitis, is a common causes and there are very effective medications available for treating this problem. As always the diagnosis and the management of your particular concern will require a physical examination by your personal physician. Setting up an office visit with your primary care doctor
might be advised.