Last updated: June 2, 2025
Understanding the UV Index is crucial for residents of Portland, Oregon, where the mix of a Cfa climate and varying sun exposure can significantly impact skin health. With UV levels reaching a peak of 11 during midday, awareness is key in preventing sunburn and long-term skin damage. In this lush, often overcast city, many may underestimate the potential risks on sunny days; however, even brief exposure to high UV levels can lead to harmful effects. Stay informed and protect your skin by keeping an eye on the UV Index throughout the day!
The UV Index for the day presents a fascinating variation as the sun climbs higher in the sky. Starting from a gentle 1 at 07:00, the intensity gradually escalates, reaching a moderate 4 by 09:00. The peak hits at 12:00 and 13:00, soaring to an intense 11, indicating a significant risk of harm from unprotected sun exposure. As the afternoon unfolds, the index begins to decline, tapering to 8 at 15:00, and by the evening, it plummets back to a 1 by 18:00. This data serves as a reminder to stay vigilant about sun safety during those peak hours when UV exposure is at its highest!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 2 | low | 45 min |
| 09:00 | 4 | moderate | 30 min |
| 10:00 | 7 | high | 25 min |
| 11:00 | 9 | very high | 15 min |
| 12:00 | 11 | extreme | 10 min |
| 13:00 | 11 | extreme | 10 min |
| 14:00 | 10 | very high | 15 min |
| 15:00 | 8 | very high | 15 min |
| 16:00 | 5 | moderate | 30 min |
| 17:00 | 3 | moderate | 30 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 1 | low | 45 min |
During the year, UV Index levels exhibit notable seasonal changes, with the highest risk months occurring from April to August. April and May both feature a very high UV Index of 10, while June and July reach an extreme level of 11, necessitating vigilant sun protection. The burn time decreases significantly during these months, dropping to just 10 minutes in June and July. Conversely, UV levels are moderate in January, November, and December, allowing for longer burn times of 30 minutes. Residents and visitors are advised to take precautions, especially during high-risk months, by seeking shade, wearing protective clothing, and applying sunscreen regularly to minimize the risk of overexposure. Awareness of these UV changes is crucial for maintaining skin health throughout the year.
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 |
| Portland | 3 | 6 | 7 | 10 | 10 | 11 | 11 | 10 | 9 | 7 | 5 | 3 |
| 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 |