Last updated: May 3, 2025
Understanding the UV Index is crucial for residents of San Carlos, United States, where the sun's rays can pose significant risks due to its warm BWh climate. Awareness of UV levels is essential not only for preventing painful sunburns but also for protecting long-term skin health and reducing the risk of skin cancers. During peak hours, particularly between 10:00 AM and 2:00 PM, the UV Index can soar as high as 11, indicating an extreme risk of harm from unprotected sun exposure. By staying informed about the UV Index, you can take proactive steps to safeguard yourself and your loved ones from harmful effects of the sun's rays.
The UV Index throughout the day showcases a remarkable rise, peaking impressively at 11 between noon and 1 PM. Starting with a modest 1 at 7 AM, the index escalates to around 3 by 8 AM and rapidly climbs, hitting 5 by 9 AM. The ascent continues as the sun reaches its zenith, soaring to 8 at 10 AM and breaching the 10 mark by 11 AM. As we reach peak sun hours, it stabilizes at 11 for both 12 PM and 1 PM, before gradually descending to 9 at 2 PM and tapering off to 7 by 3 PM. The latter part of the afternoon sees a gentle decline to 4 at 4 PM, finally returning to the morning's low of 1 by 6 PM, and maintaining this relaxed level through 7 PM. It's a vivid reminder of the sun's strength, urging outdoor enthusiasts to stay sun-smart during the intense midday 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 | 8 | very high | 15 min |
| 11:00 | 10 | very high | 15 min |
| 12:00 | 11 | extreme | 10 min |
| 13:00 | 11 | extreme | 10 min |
| 14:00 | 9 | very high | 15 min |
| 15:00 | 7 | high | 25 min |
| 16:00 | 4 | moderate | 30 min |
| 17:00 | 2 | low | 45 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, seasonal UV changes indicate significant variations in sun exposure risk. During the high-risk months of March through August, UV Index levels peak, reaching extreme levels (11-12) from April to July. It's crucial for both visitors and residents to take protective measures, particularly in these months, where the burn time drops to just 10 minutes. Even in September and October, with UV levels still classified as very high, caution is warranted. For safety, individuals should utilize sunscreen, wear protective clothing, and limit sun exposure during peak hours. In contrast, the moderate UV months of January, November, and December offer a reprieve, allowing for longer safe exposure times of 30 minutes. Regularly checking the UV index can help mitigate skin damage and promote sun safety 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 |
| Los Angeles UVI | 4 | 6 | 8 | 9 | 10 | 11 | 11 | 10 | 10 | 7 | 5 | 4 |
| San Carlos | 4 | 6 | 9 | 11 | 11 | 12 | 11 | 11 | 10 | 8 | 5 | 4 |
| Houston UVI | 5 | 8 | 9 | 11 | 11 | 12 | 12 | 11 | 10 | 9 | 7 | 5 |