When I think of winter, I picture frost on the windows, wool hats pulled down over ears, and hot cups of tea. The idea of reaching for a bottle of sunscreen seems almost silly. After all, most of us associate SPF with long days at the beach or afternoons by the pool. Yet dermatologists remind us that the sun doesn’t punch a time‑clock simply because the temperature drops. Those invisible ultraviolet rays continue to reach our skin even when we’re bundled up – and cold air brings its own set of challenges.

Why cold weather doesn’t mean zero UV

A common assumption is that ultraviolet (UV) levels fall in tandem with the mercury. It’s true that the angle of the sun changes in the winter; our part of the planet tilts away and overall UV indices tend to be lower. But temperature and UV radiation aren’t locked together. The National Cancer Institute cautions that clouds reduce UV levels by only about half, and the longer UVA wavelengths that cause tanning, dark spots and wrinkles remain constant through all seasons. UVA can even slip through glass and fog, which means that sitting by a window with a mug of cocoa still exposes your skin to radiation.

Winter also brings subtle astronomical effects. In the Northern Hemisphere, we’re actually closer to the sun during December and January, and the ozone layer that filters UV radiation tends to thin during cold months. That combination allows more of those invisible rays to reach the surface.

The snow‑reflection factor

If you’ve ever spent time on the slopes, you’ve probably noticed that everything feels brighter. Snow and ice work like tiny mirrors, bouncing sunlight back toward your face. The Skin Cancer Foundation notes that snow reflects up to 80 % of the sun’s UV light. Some sources put that number even higher, up to 90 %. This reflected light means your skin is getting hit from above and below. Even clouds can’t fully block it; up to 80 % of UV rays pass through overcast skies.

That reflection matters because it doubles exposure. Anyone who skis, snowboards or even takes long walks on a snowy day should treat sunscreen as part of their winter gear. High altitude compounds the problem: UV levels increase roughly 6 % for every 1,000 feet (about 300 m) of elevation gain, and the thinner atmosphere at altitude absorbs less radiation.

UVA, UVB and what they do to your skin

The sun’s rays come in a spectrum. UVA wavelengths are long enough to penetrate deeper into the skin. They damage DNA and contribute to premature ageing and certain skin cancers. UVB rays are shorter and more energetic; they’re responsible for the burn you feel after too much unprotected time outside. Both types are present whenever the sun is out, even in winter. Regular exposure without protection accelerates wrinkles, breaks down collagen and can trigger dark spots.

Many people equate sun damage with sunburn, but dermatologists warn that visible redness is only the tip of the iceberg. Cumulative UV exposure accounts for as much as 90 % of the skin changes we associate with ageing. Over time it increases the risk of actinic keratoses, precancerous lesions, and various forms of skin cancer.

Dryness, cracked lips and winter skin

Cold air doesn’t just feel uncomfortable; it also saps moisture from the skin. Indoor heating and wind amplify this effect, leaving the skin’s natural barrier compromised. When that barrier is weakened, UV radiation causes more damage. The result can be a combination of dryness, flakiness and hyperpigmentation. Even the delicate skin on the lips isn’t immune, which is why dermatologists recommend lip balms with added SPF.

How to protect yourself

The good news is that protecting winter skin isn’t complicated. Here are some dermatologist‑approved tips:

·      Use a broad‑spectrum sunscreen. Make sure your product protects against both UVA and UVB rays and has at least SPF 30. Broad‑spectrum coverage is essential because UVA causes ageing and UVB causes burns. Some experts suggest SPF 35 or higher.

·      Apply generously and don’t forget tricky spots. Cover all exposed skin, including ears, the back of the neck, tops of hands, and the hairline. If you’re at high altitude or spend long hours outside, consider SPF 50 or higher.

·      Reapply regularly. UV filters break down over time. Dermatologists recommend reapplying every two hours, or more often if you’re sweating or wiping your face.

·      Layer with moisturiser. Winter sunscreens that include hydrating ingredients like lanolin, glycerin or ceramides help combat dryness. Apply your regular moisturiser first and finish with sunscreen to seal in moisture.

·      Add physical barriers. Hats, scarves and UV‑blocking sunglasses provide an extra shield. According to the Skin Cancer Foundation, faces, heads and necks remain exposed year‑round, and these are the areas where most skin cancers occur.

·      Time your outdoor activities. The National Cancer Institute advises limiting direct sun exposure during peak hours – roughly 10 a.m. to 4 p.m. even in winter.

A ritual as routine as your morning juice

Making sunscreen a year‑round habit isn’t about fear; it’s about respecting the quiet power of sunlight. Whether you’re skiing down a mountain, shoveling snow or just running errands on an overcast day, those invisible rays are there. A thoughtful skincare routine can help you enjoy winter’s beauty without paying for it later. So pull on your boots, and put on that SPF – your skin will thank you.