Many people know the risks of exposure to the mid-day sun, but can you get a sunburn after 5pm?

A common misconception about sunscreen is that you should only be applying and reapplying it when the sun is out and high in the sky. If you're wondering whether you can get sunburn into the late afternoon or evening hours, the simple answer is yes.

How can that be? Why should you apply sunscreen even if it isn't sunny out? Read on to discover what Dermatologist Dr. Marisa Garshick has to say about getting a sunburn late in the day or when it's overcast.

It's Not Just About the Time of Day

According to Dr. Garshick, the likelihood of getting a sunburn relies on the ultraviolet (UV) index, a scale derived from a combination of factors, which essentially measures the strength of UV radiation from the sun. A given day's UV index number (the one that you might see in a weather forecast, for example) is usually a figure from one to 10 that indicates the intensity of the sun's rays at solar noon (the time when the sun is at its highest). In reality, this number will vary based on the place and time at which it is measured.

Garshick explains that UV rays are at their strongest between 10am to 4pm This is why experts generally recommend avoiding sun exposure during these peak times. But the potential for getting sunburn at 5 p.m. and after does still exist. "There are still some UV rays being emitted from the sun after 4 p.m.," she says. "Sometimes, your location can factor into how likely it is to get a sunburn after 5 p.m.; it depends on the intensity of the sun in a given place at that time."

The Other Factors to Watch

There are other things to consider when thinking about UV exposure. Garshick also says it's possible to get sunburn when it's overcast, as UV rays can still reach the skin even if it doesn't seem bright out. The American Cancer Society supports this and lists other factors, too. For example:

  • UV exposure increases with proximity to the equator, as the UV rays travel a much shorter distance through the earth's atmosphere. The shorter the distance, the less dispersion of the harmful rays.
  • Exposure rises with altitude. UV strength can increase 10 to 12 percent with every 1,000 meters that you travel above sea level, as you are closer to the sun.
  • Reflection off of certain surfaces can affect the amount of UV exposure you get. Water and snow are particularly reflective, and even pavement and grass can reflect UV rays.

Daily Sunscreen Application Is Key

The all-day and all-weather effects of UV exposure on your skin are many, including painful burns, wrinkles, premature aging, and even skin cancer after cumulative (but preventable) damage. Because of this, it's important to remember to apply a daily broad-spectrum sunscreen with SPF 30, even if it's before or after peak hours of sun exposure. And if you do happen to get a sunburn during these off-peak times, Garshick says that the treatment is the same. She recommends taking a cool shower or applying cold compresses or soothing creams. Further, she says you can also take ibuprofen to help reduce inflammation and use gentle cleansers and moisturizers to soothe the burn.

So, the next time someone asks if you can even get a sunburn after 5 pm, you'll now know the answer and how best to protect against it.