Last updated: August 1, 2025
Understanding the UV Index is crucial for residents and visitors of Ketchikan, United States, where the maritime climate can lead to variable sun exposure. As the UV levels rise, particularly during the midday hours when peaks can reach 8, awareness becomes essential in preventing sunburn and protecting skin health. Ketchikan's cool and temperate climate may seem less intense than other regions, but the risk of harmful UV rays is still significant, especially during the sunniest months. By keeping an eye on the UV Index, you can enjoy the stunning outdoor adventures that this unique city offers while safeguarding your skin against potential damage.
The UV Index throughout the day showcases a dynamic range of exposure, beginning at a low 1 at 7:00 AM and gradually climbing to a peak of 8 between 12:00 PM and 1:00 PM. This signifies a critical window for sun protection, particularly around 11:00 AM and 12:00 PM when the index reaches 7 and 8, respectively. As the afternoon unfolds, the index gradually declines, dipping back to 6 by 3:00 PM and then further to 4 at 4:00 PM. By the evening, the UV intensity has diminished to a gentle 1 at 7:00 PM. It's essential to stay aware of these fluctuations, ensuring that sun safety measures are taken during peak hours!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 2 | low | 45 min |
| 09:00 | 3 | moderate | 30 min |
| 10:00 | 4 | moderate | 30 min |
| 11:00 | 6 | high | 25 min |
| 12:00 | 7 | high | 25 min |
| 13:00 | 7 | high | 25 min |
| 14:00 | 6 | high | 25 min |
| 15:00 | 5 | moderate | 30 min |
| 16:00 | 4 | moderate | 30 min |
| 17:00 | 2 | low | 45 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 1 | low | 45 min |
As the seasons change, so does the UV Index, which indicates the level of ultraviolet radiation reaching the Earth, directly affecting skin health. January and February see low levels of UV exposure (UV Index 1-2), with a burn time of 45 minutes. However, March marks the beginning of more intense exposure, escalating to a moderate level (UV Index 3) with a burn time of 30 minutes. By April and May, the UV Index climbs to 5 and 6, categorizing the exposure as moderate to high, necessitating caution with a reduced burn time of 25 minutes. The peak risk occurs in July, when the UV Index reaches 8, categorized as very high, allowing for just 15 minutes of unprotected sun exposure. August and September see a slight decrease, but caution remains essential as the Index stays high at 6-7. October returns to moderate levels (UV Index 3) before dropping back to low levels through November and December (UV Index 1). Visitors and residents should prioritize sun safety, particularly from March to September, wearing protective clothing, and applying sunscreen to avoid skin damage.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Ketchikan | 1 | 2 | 3 | 5 | 6 | 7 | 8 | 7 | 5 | 3 | 1 | 1 |
| 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 |