Memorial Day weekend is here and it signifies the unofficial start of summer, and Memorial Day itself has also unofficially been dubbed "Don't Fry Day," to remind us about the dangers of sun exposure.

One in five Americans will develop skin cancer by age 70, and there are more skin cancer diagnoses than all other cancers combined, says Dr. Eric M. Ascher of the ABC News Medical Unit. The American Academy of Dermatology says about 9,500 people in the U.S. are diagnosed with skin cancer every day.

Many dermatologists suggest using SPF 30 or higher sunscreen to protect against ultraviolet A (UVA) and ultraviolet B (UVB) rays, which cause a whopping 90 percent of non-melanoma skin cancers and 86 percent of melanomas. It should be applied 20 minutes before going out and reapplied two hours later, even if it's overcast.

Oh..one more thing: stay out of tanning beds!