Fall ushers in cooler weather for much of the United States, and if you have psoriasis, this can mean more than leafless trees and higher heating bills. Although there’s no scientific evidence to explain why cold weather can trigger psoriasis flares, the National Psoriasis Association (NPF) says many people experience a worsening of their symptoms when the temperature dips.

One study, published in Clinical, Cosmetic and Investigational Dermatology, found that just over half of participants had aggravation of their psoriasis condition in the fall and/or winter. “Cold weather combined with low humidity can accelerate moisture loss in our skin,” explains Tanya Nino, M.D., a board-certified dermatologist with St. Joseph Heritage Medical Group in Orange County, California.

Plus, we often crank up the indoor heat during the winter months, which can strip the skin of its natural oils. “These conditions can cause psoriasis to be more itchy and uncomfortable due to flaking, cracking, and dry skin,” Nino says.