Last updated: July 2, 2025
Understanding the UV Index is crucial for residents of Twain Harte, United States, where the sun shines ambitiously throughout the year. In a climate classified as Csa, locals face a unique set of UV exposure risks, especially during peak hours. Awareness of UV levels not only helps in preventing sunburns but is also vital for long-term skin health. With UV Index values soaring to as high as 11 around midday, it's essential to stay informed and take appropriate precautions to protect your skin while enjoying the beautiful outdoors of Twain Harte.
As the sun rises, the UV Index gradually climbs, starting at a mild 1 at 07:00. By 09:00, it reaches a moderate 4, signaling a need for some sun protection. The intensity peaks at 12:00 with a powerful 10, indicating strong sunlight. The highest point, 11 at 13:00, urges sun safety awareness as the afternoon sun bears down. However, relief comes as the sun begins to set; the index dips to 9 by 15:00, then gradually decreases to 4 at 17:00, and finally back to a safe 1 by 19:00. Throughout the day, staying vigilant against UV exposure is key!
| 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 | 9 | very high | 15 min |
| 12:00 | 10 | very high | 15 min |
| 13:00 | 11 | extreme | 10 min |
| 14:00 | 10 | very high | 15 min |
| 15:00 | 9 | 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, reflecting seasonal changes in sun exposure. January and December both see a UV Index of 3, categorized as moderate, with a burn time of 30 minutes. As spring approaches, February reaches a UV Index of 5 (moderate), while March escalates to 8 (very high), indicating a sharp increase in potential sunburn risk. The peak months for UV exposure occur from April to July, with July remaining constant at a critical UV Index of 11, categorized as extreme; during this period, only 10 minutes of unprotected sun exposure can lead to burns. As summer transitions to fall, the UV Index gradually declines, with September at 9 (very high) and heading into October at 7 (high), where the burn time increases to 25 minutes. With these fluctuations in mind, it is essential for visitors and residents to take precautionary measures, especially from March through August, when UV levels are particularly high; wearing sunscreen, protective clothing, and seeking shade during peak sunlight hours can greatly reduce the risk of sunburn and long-term skin damage.
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 |
| Twain Harte | 3 | 5 | 8 | 9 | 11 | 11 | 11 | 10 | 9 | 7 | 4 | 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 |