Last updated: June 2, 2025
In Portsmouth, United States, understanding the UV Index is crucial for safeguarding your skin and overall health. With UV levels peaking at a significant 10 during midday, being aware of these fluctuations can help prevent sunburn and long-term skin damage. The city's Cfa climate brings warm summers and moderate UV exposure risks, making it essential for residents and visitors alike to stay informed. By tracking the UV Index, you empower yourself to enjoy the sun safely, ensuring that your time outdoors doesn’t come at the cost of your skin health.
The UV Index data unveils a dynamic progression of sun intensity throughout the day. Starting low at 1 at 07:00, the index gradually escalates, reaching maximum levels of 10 between 12:00 and 14:00. This peak signals a critical time for sun protection. As the afternoon wanes, the index tapers off to 8 at 15:00, and then descends further to 3 by 17:00, and 2 by 18:00. Ultimately, the day concludes softly with a return to 1 at 19:00. It's essential to stay vigilant during those peak hours to safeguard your skin while enjoying the sun!
| 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 | 6 | high | 25 min |
| 11:00 | 8 | very high | 15 min |
| 12:00 | 10 | very high | 15 min |
| 13:00 | 10 | very high | 15 min |
| 14:00 | 10 | very high | 15 min |
| 15:00 | 8 | very high | 15 min |
| 16:00 | 6 | high | 25 min |
| 17:00 | 3 | moderate | 30 min |
| 18:00 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
As the seasons change, so do the UV Index levels, reflecting varying risks for sun exposure throughout the year. January sees a moderate UV Index of 4, with a burn time of 30 minutes, while February escalates to a high index of 6, reducing burn time to 25 minutes. The risks peak in spring and summer, with March through July experiencing very high to extreme levels, particularly in July at a dangerous 11, where just 10 minutes of sun can cause burns. As summer wanes, August and September remain risky, however, the index gradually decreases through October to December, where it levels out to a moderate index of 5 and 3 respectively, allowing for safer exposure of 30 minutes. For both visitors and residents, it is crucial to prioritize sun safety during the high-risk months of March through September, especially in July when the UV exposure is at its peak. Always wear protective clothing, utilize sunscreen, and seek shade during peak sunlight hours to mitigate the risk of harmful effects from UV radiation.
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 |
| Portsmouth | 4 | 6 | 8 | 9 | 10 | 10 | 11 | 10 | 9 | 8 | 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 |