UV index 11+ is the highest reading on the UV index scale. When the UV index is 11 or greater there is an extreme risk of harm from unprotected Sun exposure. According to the UV index scale, you should avoid being outdoors when the UV index is 11. If you’re going to be outside, wear sun protective clothing, a hat, and sunglasses if you’re going to be in the Sun. Use a sunscreen that is broad-spectrum and SPF-15 or higher on exposed skin, reapply every two hours.
It's easy to find your local UV index forecast. Enter your city and state above and hit the "Find Forecast" button.