Last updated: May 3, 2025
Understanding the UV Index in Portland is crucial for maintaining healthy skin and preventing sunburn, especially as the city experiences its fair share of sunny days. With a climate categorized as Dfb, Portland has distinct seasonal variations that influence UV exposure, peaking at levels as high as 9 during midday hours. This highlights the importance of being aware of daily UV levels; knowing when to seek shade or apply sunscreen can protect your skin from harmful ultraviolet rays while enjoying the city's outdoor charms. Stay informed and keep your skin safe to make the most out of Portland's vibrant sunshine!
As the sun rises, the UV Index begins its ascent, starting at a gentle 1 at 07:00. By 08:00, it climbs to 2, indicating a mild increase in UV exposure. The real peak arrives at 12:00, where the index reaches a striking 9, underscoring the importance of sun protection during these hours. This high level remains steady until 14:00, followed by a gradual descent as the afternoon wanes: 8 at 15:00, 6 at 16:00, and continuing down to 2 at 18:00. As evening approaches, the UV Index drops to a soft 1 by 19:00, signaling a gentle close to the sun-soaked day. Remember to take precautions during the midday hours to safeguard your skin!
| 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 | 5 | moderate | 30 min |
| 11:00 | 7 | high | 25 min |
| 12:00 | 9 | very high | 15 min |
| 13:00 | 9 | very high | 15 min |
| 14:00 | 9 | very high | 15 min |
| 15:00 | 8 | very high | 15 min |
| 16:00 | 6 | high | 25 min |
| 17:00 | 4 | moderate | 30 min |
| 18:00 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, the UV Index experiences significant fluctuations, peaking during the summer months. January and December register low UV exposure levels (Index 2), allowing for longer safe sun exposure times of around 45 minutes. As February progresses to an Index of 4, caution becomes necessary, with a burn time of 30 minutes. The high-risk months emerge from March to September, where the Index ranges from 6 to 10, signaling very high UV levels for much of the summer; notably, April to August sees a consistent Index of 8-10, with a critical burn time of just 15 minutes. In this period, it's vital for visitors and residents to take precautions by seeking shade, wearing protective clothing, and applying sunscreen regularly. As the year transitions into fall, the UV Index declines, although October still presents a high risk at 6. Emphasizing sun safety during peak months is essential to prevent harmful UV exposure.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Portland | 2 | 4 | 6 | 8 | 9 | 10 | 10 | 9 | 8 | 6 | 4 | 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 |