Many people associate the risk of sunburn with high temperatures, but according to Cancer Research UK, the sun's UV rays can damage the skin from mid-March to mid-October, even on cloudy days.
The organization states that more than 90 percent of UV rays can penetrate cloud cover.
A good rule of thumb is to look at your shadow. If it is shorter than you are, the sun's rays are often at their strongest, The Sun reports.
Sunscreen is not enough
The NHS recommends using sunscreen with at least SPF 30 and high UVA protection.
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Sunscreen should be applied to all skin that is not covered by clothing, and it should be reapplied after swimming or heavy sweating.
According to the NHS, you should also seek shade, wear a wide-brimmed hat, and choose lightweight clothing that covers your skin.
People with fair skin or a large number of moles should be especially careful, but those with darker skin can also get sunburned and develop skin cancer.
The number that matters
The most important factor is not the temperature but the UV Index, which indicates the intensity of the sun's UV radiation.
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The higher the number, the more quickly your skin can be damaged.
According to the NHS, you should protect your skin whenever the UV Index is 3 or higher.
If it reaches 8 or above, everyone should take protective measures regardless of their skin type.
The UK Health Security Agency also emphasizes that both sunburn and a suntan are signs that the skin has been damaged by UV radiation.
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