With temperatures changing from warm to cold, I have very real concerns about properly transitioning my (itchy, flaky) scalp for the weather. And according to according to Jodi LoGerfo, DNP, APRN, FNP-C, a board-certified dermatologist, I’m not wrong to be worried: Your scalp can be affected by seasonal variations, especially humidity, temperature, UV light, and the environment. “Sometimes people notice changes in their hair or scalp during seasonal variations, which can be especially true in the winter. The dry, cold air of the winter months can cause both the hair and scalp to become dehydrated, leading to dryness and itchiness in the scalp,” she says. Colder weather also brings drier environmental conditions due to indoor heating and changes in humidity.