Last updated: June 2, 2025
Understanding the UV Index in Key West, United States, is crucial for anyone looking to enjoy the sun safely in this tropical paradise. With soaring UV levels peaking around midday, knowing the intensity of ultraviolet radiation is vital for effective sunburn prevention and maintaining skin health. Key West’s sunny and humid climate can expose residents and visitors to significant UV risks, especially during the summer months. Staying informed about the UV Index helps you protect your skin and enjoy the beautiful outdoor lifestyle this vibrant location has to offer.
As the sun rises on this bright day, the UV Index starts off relatively low, peaking at just 1 at both 7:00 AM and 8:00 AM. However, by 9:00 AM, it jumps to 3, signaling an increase in UV exposure. The intensity escalates quickly, reaching a notable 6 by 10:00 AM. The real intensity hits its peak at 12:00 PM, when the UV Index soars to a striking 12, followed closely by a high of 13 at 1:00 PM. Over the next few hours, the index gradually diminishes, but still remains significant with 10 at 3:00 PM and 7 by 4:00 PM. As evening approaches, the levels continue to decline, returning to 1 once dusk settles in at 7:00 PM. Be sure to protect your skin!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 1 | low | 45 min |
| 09:00 | 3 | moderate | 30 min |
| 10:00 | 6 | high | 25 min |
| 11:00 | 9 | very high | 15 min |
| 12:00 | 12 | extreme | 10 min |
| 13:00 | 13 | extreme | 10 min |
| 14:00 | 12 | extreme | 10 min |
| 15:00 | 10 | very high | 15 min |
| 16:00 | 7 | high | 25 min |
| 17:00 | 4 | moderate | 30 min |
| 18:00 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, UV index levels vary significantly, with the highest risk months occurring from March to September, peaking at UV Index 13 in June. The extreme exposure category (UV Index 11-13) highlights the urgent need for protective measures, as the burn time during these months drops to just 10 minutes. February also poses a threat with a very high index of 9 and a burn time of only 15 minutes. Visitors and residents are strongly advised to take precautions, such as wearing sunscreen, protective clothing, and seeking shade during peak sunlight hours, especially during the high UV months of March through September. As the year progresses, the index generally decreases, with January and December being relatively safer months, registering high levels but allowing for longer exposure times of 25 minutes. Remaining vigilant about UV exposure year-round is essential for skin protection and overall health.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chicago UVI | 3 | 4 | 6 | 8 | 9 | 10 | 10 | 9 | 8 | 6 | 4 | 2 |
| Brooklyn UVI | 3 | 5 | 6 | 8 | 10 | 10 | 9 | 9 | 8 | 6 | 4 | 2 |
| New York City UVI | 3 | 5 | 6 | 8 | 10 | 10 | 9 | 9 | 8 | 6 | 4 | 2 |
| Los Angeles UVI | 4 | 6 | 8 | 9 | 10 | 11 | 11 | 10 | 10 | 7 | 5 | 4 |
| Houston UVI | 5 | 8 | 9 | 11 | 11 | 12 | 12 | 11 | 10 | 9 | 7 | 5 |
| Key West | 7 | 9 | 11 | 12 | 12 | 13 | 12 | 12 | 11 | 10 | 8 | 6 |