If you’ve ever looked up at a cloudy sky and decided to skip out on your daily sunscreen application (which, let’s be honest, most of us are guilty of doing), there’s something you should know: It’s just as important to lather your skin with something with SPF when it’s overcast as it is when it’s bright and sunny.
Why clouds don't protect you from the sun
“Clouds give us a false sense of security and lead us to underestimate how much radiation from the sun we are getting,” Dr. David Lortscher, board-certified dermatologist and CEO and founder of Curology, tells SheKnows. “We tend to stay outside longer on cloudy days thinking we aren’t getting much sun — so overexposure to sun can happen without our being aware of it, resulting in tanning, which is a sign of sun damage and/or burning.”
While we all have some sense that UV rays plus skin equals bad news, it’s important to understand what that actually means.
“People relate sunburns and sun damage to heat and sunlight, but UV is invisible,” DC-based dermatologist Dr. Lily Talakoub of McLean Dermatology and Skincare Center tells SheKnows. She explains that you can't see UV rays in the form of light or feel it in the form of heat but you should know that any time of the day there's daylight, UV rays are there too. And so even if it's cloudy or rainy, the UV rays can go right through the clouds as well as glass windows because it's technically not light, but a form of radiation, she notes.
Both UVA and UVB rays — which are differentiated by their wavelengths — can cause skin aging and skin cancers and are each fully capable of penetrating the clouds on an overcast afternoon, Talakoub explains. The same principles also apply during the winter, which is why even when you're freezing to the bone in the middle of February, you should still be regularly applying sunscreen.
While clouds do provide some sun protection, you’re still better off playing it safe. According to the Environmental Protection Agency, clear skies allow virtually 100 percent of UV to pass through, scattered clouds transmit 89 percent, broken clouds transmit 73 percent, and overcast skies transmit 31 percent, which means that no matter how overcast it is, your skin is never totally safe.
How to protect yourself in all weather
To protect yourself properly, Lortscher suggests lathering on a broad-spectrum sunscreen with at least an SPF of 15 before you head outside. Some of his facial favorites include Neutrogena Sensitive Skin Sunscreen Broad Spectrum SPF 60+, CeraVe AM SPF 30 and Drunk Elephant Umbra Sheer Physical Daily Defense Broad Spectrum Sunscreen SPF 30.
Equally as important as lathering up before you leave home, though, is continuously reapplying regularly throughout the day — you may think it’s unnecessary, but it’s critically important to remain covered, especially if you’re going to be spending a lot of time outside.
"Unprotected exposure to UV radiation is the most preventable risk factor for skin cancer,” Lortscher says. "Cumulative exposure adds up over the days, weeks, months and years of our lives. Do what you can when you can to minimize your lifetime UV exposure — every hour counts, even on cloudy days.”