Last updated: June 2, 2025
Understanding the UV Index is essential for residents of Portland, Oregon, where sun exposure can be deceptive, especially in the temperate Dfb climate. As UV levels can rise sharply during midday, being aware of these values is crucial for preventing sunburn and protecting overall skin health. With maximum UV readings peaking at 10 around noon, Portlanders should stay informed to mitigate risks, particularly during the warmer months when outdoor activities are at their peak. Whether enjoying the city's vibrant parks or basking in the sun, knowing the UV Index helps ensure that your skin remains safe while you soak in all that Portland has to offer!
As the sun rises, the UV Index starts off low, hitting just 1 by 07:00 and maintaining that level through 08:00. However, as the morning progresses, anticipation builds with a steady climb to 3 by 09:00 and peaking at a noteworthy 5 by 10:00. The intensity escalates sharply, reaching a maximum of 10 between 13:00 and 14:00, indicating a significant risk for unprotected skin. Gradually, the UV Index begins to decline, dropping back to 9 at 15:00 and easing down to 5, 3, and finally 2 as the day winds down through 17:00 to 19:00. A day to remember for sun seekers, but remember to apply that sunscreen during peak hours!
| 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 | 5 | moderate | 30 min |
| 11:00 | 7 | high | 25 min |
| 12:00 | 9 | very high | 15 min |
| 13:00 | 10 | very high | 15 min |
| 14:00 | 10 | very high | 15 min |
| 15:00 | 9 | very high | 15 min |
| 16:00 | 7 | high | 25 min |
| 17:00 | 5 | moderate | 30 min |
| 18:00 | 3 | moderate | 30 min |
| 19:00 | 2 | low | 45 min |
As the seasons change, so do UV levels, highlighting periods of higher risk for sun exposure. From January to March, the UV Index remains low to moderate, with February seeing an increase. April to August marks the peak high-risk months, featuring very high UV levels, particularly in June and July, where the burn time drops to a remarkable 15 minutes. September transitions into a high UV category, while October to December see a gradual decline, returning to low risk by year's end. To protect yourself, especially during the high UV months of April through August, it is crucial to wear sunscreen, protective clothing, and seek shade to minimize exposure. Be particularly vigilant during the summer months when burn time is significantly reduced.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Portland | 2 | 4 | 5 | 8 | 9 | 10 | 10 | 9 | 7 | 5 | 3 | 2 |
| 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 |