Hot + Humid weather
WHAT EXACTLY CHANGES IN THE SKIN: A lot— when it’s hot, your skin’s job is to help cool your body. Excess heat from inside the body is released by expanding blood vessels closer to the skin’s surface (that’s why you look rosy and flushed when it’s very hot). Sweat glands start perspiration (sweating) bringing water to the surface to further cool you down- the tradeoff cost to your skin is access TEWL (TransEpidermal Water Loss) from inside your skin. Unfortunately, skin’s natural cooling process doesn’t work well in high humidity. The heavy, wet air prevents sweat from easily escaping off your skin, trapping heat, wetness (and everything flowing in the wet air) onto your skin. (That’s why 85 degree in a tropical climate feels more like 95 degrees)
When skin releases heat, the natural skin lipids turn from waxy into oily. Mixed with trapped sweat, your pores get easily clogged and inflammation starts. Intense and strong UV light and pollution attack barrier functions and skin cell health.