The sun shines brightly every day, and despite cloud cover, UV radiation still penetrates to the earth. The Skin Cancer Foundation reports that on average, cloud cover only blocks 20% of the sun’s rays. In particular, UVA rays have a longer wavelength than UVB rays, allowing them to more easily pass through clouds. UVA rays might not give you a sunburn, but they are the rays that penetrate deeply in the skin to cause aging and skin cancer.While it might feel cooler on a cloudy day, it is still important to maintain your usual protective behaviours with a high SPF sunscreen or sun protective clothing! Finally, weather can change on a dime and once the clouds clear you may find yourself in intense sunlight with no or minimal sun protection.