What is the cause of rhinitis? When the weather is cold, my nose is blocked.

From the description of your illness, you think it is allergic rhinitis. Encountering cold air will aggravate the symptoms of nasal congestion and make the nose unobstructed.

It is suggested that when the symptoms of allergic rhinitis are obvious, glucocorticoid nasal spray and oral antiallergic drugs should be considered to avoid cold air stimulation.