Home
Weather London
WeatherRadar
RainfallRadar
TemperatureRadar
WindRadar
LightningRadar
Weather News
Editor's Pick
Discover the app
Weather widget
Contact us
Apps
Career
Home / Editor's Pick /

UV Radiation: UVA, UVB and the UV Index

11:00
10 July 2022

Safety in the sun
UV Radiation: UVA, UVB and the UV Index

sunshine

As temperatures are rising across the British Isles, most of us are spending more time outside. But with the longer, hotter and sunnier days comes the danger of increased ultraviolet (UV) radiation.

UV radiation is a type of energy produced by the sun ray's and is the main cause of skin cancer.

The sun's UV rays can reach people in three ways: directly from the sun, scattered and/or reflected by the environment depending on the time of day, season and your location.

Even on a cloudy day, UV levels can be high as it is able to be reflected and scattered in the clouds.

There are three types of UV rays: UVA, UVB and UVC. UVC is the most dangerous form of UV radiation, but luckily this is absorbed by the atmosphere before it reaches Earth. UVB penetrates the top layer of the skin and leads to sunburn.

UVA, however is the most potent source of UV which we are exposed to all year long. UVA can even pass through windows and clouds and penetrates deep into our skin leading to ageing and increases our risk of skin cancer.

Because of the dangers associated with increased levels of UV, particularly in the summer months when UV radiation is at its strongest, the UV Index was created:

The UV Index helps individuals make decisions about how much time should be spent in the sun and what level of protection will be needed.

The higher the UV Index, the stronger the strength of the UV and faster skin will burn.

Across parts of the UK, UV levels are forecast to reach 7 or 8 on the UV Index.

When UV levels are forecast this high, it means there is a risk of burning within 15-30 minutes, with individuals advised to keep out of direct sunlight around midday.

It is also important to make sure protective clothing is worn and sun scream with an SPF of 30 is applied every two hours to prevent sunburn and irritation.

Weather & Radar editorial team
More on the topic
A harbour in Crete with a reddish-brown, overcast sky
Friday, 3 April 2026

Blood red skies

Dust storm in Crete
UK and Ireland map shaded in warm tones showing UV levels, with values up to 22 in southern England and lower values in Scotland, plus a circular UV icon.
Tuesday, 7 April 2026

Sunscreen season

UV levels rising with the warmth
Split weather graphic showing a low-pressure system with tight isobars over the UK on the left and a wind map on the right with strong gusts up to 90 mph, plus a windsock warning icon.
Thursday, 2 April 2026

Gales and blizzards

Storm Dave disrupts Easter weekend
All weather news
This might also interest you
Weather map of the UK and Ireland showing scattered showers with cloudy patches across much of the region, especially around western and northern areas. Sunshine symbols appear over London, Cardiff, and parts of southern England, while temperatures range from 17°C to 18°C in most places. Areas of heavier rain are visible over the Atlantic to the west.
Friday, 29 August 2025

Breakfast brief

Unsettled conditions into the weekend
Split image showing a person in a yellow jacket struggling against strong winds and heavy rain on a street at night on the left, and an Irish wind forecast map on the right with red and purple shading, gusts up to 75 mph, and a wind warning icon, divided by a curved white line.
Saturday, 24 January 2026

On this day...

Historic Storm Éowyn arrives
UK temperature map dated 14.02 showing widespread subzero values in blue shading, with readings such as −4 in Glasgow, −3 in Dublin, and −2 in London, alongside a blue thermometer icon.
Friday, 13 February 2026

Icy conditions

A frozen start to the weekend
All articles
Weather & Radar

Weather & Radar is also available on

Google Play StoreApp Store

Company

Contact us Privacy Policy Legal info Accessibility statement

Services

Uploader

Socials

facebooktwittertikToklinkList