Winter sun and UV

When hitting the slopes its really important to be aware of the affects of the sun - UV rays can be more damaging in alpine regions because you absorb both the direct UV rays from the sun and the diffuse UV rays reflected off of the snow. For every 1,000 feet above sea level, the amount of UV rays that reach the earth's surface increases by up to 5 per cent - a mountain at 10,000 feet receives 50 per cent more UV exposure than the same area at sea level. 

Our UV index forecast is active all year round for 417 world cities, mainly across Europe. The forecast identifies the strength of the UV radiation from the sun, allowing you to take the necessary precautions to help reduce the impact of UV on your health, whilst still enjoying the sun.


Snow reflects around 85% of the sun's UV rays so you may burn in unusual places. Look out for the underside of your chin and your ears in particular. Up to 80% of the sun's UV rays penetrate light clouds, and what gets through can reflect back and forth between the clouds and the snow. So even if it's cloudy it's important to protect yourself. The British Association of Dermatologists advises using a sun cream with a sun protection factor (SPF) of at least 30 and reapplying it regularly to all areas of exposed skin.

Extreme sunburn can be very serious and all sunburn can cause serious ongoing health effects, however most people initially experience mild symptoms, such as hot, red skin. Protecting yourself against sunburn is very important as excessive UV radiation directly damages the DNA in your skin cells. In many cases, not all of the sun damage will be fully repaired by the body's defence system, so it will gradually cause advanced skin ageing over the years and may lead to skin cancer.

Learn more about how to protect yourself from Sunburn and get up-to-date information from our UV forecast Map.

Effects of UV radiation on the eye

Diffused UV rays reflected off of the snow can mean that whilst participating in winter sports you are subjecting your eyes to twice as much UV light. This is why it is important to wear polarised sunglasses/goggles to reduce the amount of UV light reflected by the snow reaching and damaging the eye.

UV radiation can have both short- and long-term effects on the condition of our eyes. We often protect ourselves against UV by using sunscreen or wearing protective clothing but its also important to consider protecting our eyes. UV radiation from the sun can damage the eye's surface tissues as well as the cornea and lens. UV can burn the surface of the eye much like sunburn on skin. To protect your eyes from UV exposure wear good quality UV protective sunglasses.

Long-term exposure to UV radiation can be serious. Exposure to UV is a significant risk factor for cataract development which is the leading cause of blindness in the world. This is where damage is caused to the retina in the eye which is usually not reversible.

Vitamin D

Your body produces vitamin D when exposed to UV radiation from the sun. Vitamin D helps to regulate the amount of calcium and phosphate in the body, both are needed to keep bones and teeth healthy.

The amount of time you need to spend in the sun to generate enough vitamin D varies from person to person. People can often generate enough vitamin D by spending just a few minutes in the sun. This means people can take the necessary precautions to protect themselves from burning and reduce their risks of developing skin cancer whilst still enjoying the health benefits from sunlight.

UV App


Get UV forecasts for UK and worldwide locations on the Met Office app. The UV forecast shows the UV index for the next 7 days.