For some people cold weather means more headaches. What triggers an aching head in winter months? One theory is that when the cold air hits the trigeminal nerve – which supplies sensations to the face mucous membranes and other structures of the head – blood vessels in the brain constrict and causes headache. Cold whether headaches are more common in people who suffer from migraines. Another possible cause for winter headaches is the change in air pressure. The pockets of air in our head called sinuses are usually at equilibrium with the atmospheric pressure. When the air pressure changes it