Last updated: June 2, 2025
Understanding the UV Index is essential for residents and visitors in Jamestown, United States, where the subtropical climate can bring significant sun exposure. Awareness of UV levels is crucial for preventing sunburn and protecting skin health, particularly during peak hours when the index reaches dangerous levels, such as 11 between noon and 1 PM. With typical risks associated with high UV exposure in this climate zone (Cfa), being informed can help you enjoy the sunshine while effectively safeguarding your skin. Stay protected and make the most of your outdoor activities by keeping a close eye on the UV Index!
The UV Index today presents a compelling narrative of intensity as the daylight unfolds. Starting at 7:00 AM, it rises slowly from a minimum of 1, suggesting low levels of UV exposure. By 9:00 AM, it hits 5, prompting a more cautious approach for those planning outdoor activities. The sun reaches its zenith at 12:00 PM, with a striking 11, emphasizing the need for sun protection during peak hours. This level remains high until 1:00 PM, where it plateaus, then gently descends through the afternoon. By 4:00 PM, the index drops to 5, concluding the day with a modest 1 by 7:00 PM, making evening strolls safer. Always remember: the sun is strongest between 10:00 AM and 2:00 PM, so protect your skin during these hours!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 3 | moderate | 30 min |
| 09:00 | 5 | 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 |
Throughout the year, the UV Index varies significantly, with high-risk months occurring primarily from April to August, where the index reaches extreme levels of 10-11. During these months, the recommended burn time drastically decreases, dropping to as low as 10 minutes of unprotected sun exposure. Visitors and residents are advised to take extra precautions during these high UV Index periods by wearing protective clothing, applying sunscreen with a high SPF, and seeking shade during peak hours (10 AM to 4 PM). As the UV Index returns to moderate levels in January, November, and December, the risk of skin damage decreases, but sun safety remains essential year-round.
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 |
| Jamestown | 3 | 6 | 7 | 10 | 11 | 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 |