Sunscreen in Winter: Cloudy Days, Smog and Indoor Windows
Yes, sunscreen in winter still earns its place, even on grey, smoggy days. UVB, the burning rays, drops a lot in winter, but UVA, the ageing and pigment rays, carries on year round, passes through clouds and through window glass, and is what keeps melasma and tan marks stubborn.
Quick facts
- Clouds: the AAD says up to 80% of UV can pass through cloud.
- Glass: UVA passes through window glass; UVB mostly doesn’t.
- Smog: haze is not a sunscreen and gives no reliable protection.
- Winter routine: one cream sunscreen can double as moisturiser.
- Who needs it most: anyone with melasma, pigment marks, or long hours near a window or in a car.
Do I need sunscreen in winter if it’s cold?
Cold has nothing to do with it. Temperature is heat, UV is light. You can’t feel UV at all, which is why a crisp, sunny January afternoon in Islamabad or Lahore feels harmless while still putting UV on your face.
The WHO explains that UVA makes up about 95% of the UV reaching the ground, goes deeper into skin, tans quickly and contributes to ageing. UVB burns and peaks in summer, around solar noon. So in winter the burning risk falls, but the slow tanning and pigment risk doesn’t vanish. For people with brown skin that slow risk is exactly the one that matters, because uneven tone and dark patches are the common complaints. Our post on whether dark skin needs sunscreen handles that myth in full.
Sunscreen on a cloudy day: does it matter?
It does. The American Academy of Dermatology says up to 80% of the sun’s UV can get through clouds, and the WHO adds that thin cloud may barely reduce UV at all. A heavy overcast day lets through less, but you can’t easily tell which kind of day you’re in from the window.
Does smog block UV?
Thick smog in north Indian and Punjab winters can make the sun look like a pale coin. It may scatter some UV, but no health body counts it as protection, and the amount changes hour to hour. Pollution also adds its own stress to skin. Treat a smoggy day as an ordinary day and keep the habit.
Sunscreen indoors near a window
The AAD notes that UVA passes through ordinary window glass while UVB is blocked. If your desk faces a bright window, you study by one, or you spend an hour a day in a car or rickshaw with the sun on one cheek, that side of your face gets steady UVA. Many people with melasma notice the darker side is the one by the car window.
The one-step winter routine
Dry winter skin and a two-product routine rarely last. Pick a cream-textured SPF 30 or higher with glycerin or ceramides in it, and use it as your morning moisturiser. Two finger lengths for the face and neck, applied after washing. If your face is very dry, add a few drops of plain moisturiser under it first, wait a minute, then the sunscreen.
Winter sunscreen for dry skin: what to choose
| Skin type | Winter pick |
|---|---|
| Dry, tight | Cream or lotion SPF with glycerin or ceramides |
| Oily or acne-prone | Light gel or fluid; winter oiliness often drops |
| Melasma | Broad-spectrum, daily, tinted if you like it |
| Sensitive, stinging | Fragrance-free mineral (zinc, titanium) |
Glycerin and rose water mixes are a good night-time partner; see our glycerin and rose water ratio guide.
Melasma in winter: why the sun still matters
Melasma doesn’t take winter off. UVA darkens it, and UVA is present on short winter days. Patients often relax in December and see the patches deepen by March. The full plan lives in our melasma (jhaiyan) guide; the winter point is simply to keep wearing it.
- Morning: wash, moisturise if needed, sunscreen as the last skincare step.
- Before going out at midday: top up the cheeks and nose if you’ll be outside more than two hours.
- In the car: keep a small tube in the glovebox for the window side.
- Night: wash it off gently, then a richer moisturiser.
Cold days don’t block light. Sunscreen does.
Lips get forgotten in winter too, and they burn and chap on bright mountain trips to Murree or Shimla. A lip balm with SPF is a small, cheap addition for anyone heading north, skiing or walking on snow, because snow reflects a lot of light back up at the face. Kids out in the sun at a winter picnic need the same cover on cheeks, nose and ears as in summer.
Building it into a daily routine is covered in our daily sunscreen habit post.
Your skin stings with every sunscreen: switch to fragrance-free mineral filters and patch test on the neck for three days. See a dermatologist for patches that keep spreading despite daily sunscreen, any spot that changes shape or bleeds, or a rash that appears only on sun-exposed skin, which can be a light sensitivity worth checking, especially if you’ve started a new medicine (don’t stop it yourself; ask the prescriber). Babies under 6 months should be kept out of direct sun rather than covered in sunscreen.
More on caring for skin through the seasons is in Skin & Beauty.
Winter sunscreen questions
Do I need sunscreen in winter?
Yes. UVA, which tans and ages skin, is present all year and passes through clouds and glass, even when UVB is low.
Should I wear sunscreen on a cloudy day?
Yes. A large share of UV can pass through cloud, and you can’t tell how much by looking.
Do I need sunscreen indoors?
If you sit near a bright window for long periods, yes, because UVA passes through glass. In an inner room with no windows, you can skip it.
Does smog protect from the sun?
No reliable protection. The effect is unpredictable, so keep your usual sunscreen on smoggy days.
What SPF should I use in winter in Pakistan?
SPF 30 or higher, broad-spectrum, every day. The same level you’d use in summer, just in a richer texture if your skin is dry.
Can sunscreen replace moisturiser in winter?
A cream-based sunscreen often can for normal to slightly dry skin. Very dry skin may need a moisturiser underneath.
Do I need to reapply sunscreen in winter?
If you’re indoors most of the day, once in the morning is usually enough. Reapply after two hours outside.
Can winter sun make melasma worse?
Yes. UVA is present in winter and can darken melasma, so keep up daily protection.
Is tinted sunscreen better for brown skin?
Many people with brown skin prefer them because they hide white cast. Dermatologists often suggest tinted formulas for melasma; ask yours.