Why You Still Burn in the Shade
Reflected and scattered UV reaches you even under the umbrella.
Photokeratitis symptoms typically appear 6-12 hours after UV overexposure to the eyes.
Winter lips are vulnerable; dermatologists recommend an SPF lip balm year-round.
Frequently asked questions
Does UV get stronger at higher altitude?
Yes. UV intensity increases roughly 4–5% for every 1,000 feet (about 300 m) of elevation, because there's less atmosphere to filter it. At a mountain resort UV exposure can be substantially higher than at sea level — a key reason sunburn is common while hiking or skiing.
Do I need sunscreen while skiing?
Definitely. On the slopes snow reflects up to 80% of UV and altitude raises intensity about 4–5% per 1,000 feet, so exposure is intense even in the cold. Use broad-spectrum SPF 30+ on the face, ears and neck, an SPF lip balm, and UV-blocking goggles.
When is the UV index high enough to need protection?
Dermatologists generally recommend sun protection whenever the UV Index is 3 or higher. Across much of the US that threshold is reached most of the year around midday — and even lower readings add up over time, so daily broad-spectrum sunscreen is a sensible default.
r/SkincareAddiction: 'Should I wear SPF lip balm in winter?'
Sources & citations
- EPA UV Index seasonal data
- skincancer.org ↗