Last updated: June 2, 2025
Understanding the UV Index is crucial for residents and visitors in Half Moon Bay, United States, where the coastal climate can mask the sun's intensity. With UV levels peaking at 11 during midday, awareness is essential for preventing sunburn and maintaining healthy skin. As a region classified under the Csb climate zone, Half Moon Bay experiences varying UV exposure, making it vital to monitor these levels to protect yourself against harmful effects. Embrace the beauty of the California coast while keeping your skin safe by staying informed about the UV Index!
The UV Index paints a vivid picture of sun intensity throughout the day. Starting off at a low 1 at 7:00 AM, the sun begins to rise, prompting a gradual increase as it climbs higher in the sky. By 9:00 AM, the index reaches 4, indicating moderate exposure. The intensity peaks sharply at 12:00 PM with a notable 10 and hits its zenith at 1:00 PM, boasting an impressive 11. As the afternoon wears on, this extreme UV exposure begins to taper off, dropping to 9 by 3:00 PM and then descending further to 2 by 6:00 PM. Finally, as twilight approaches, the index falls back to a gentle 1 by 7:00 PM. It’s a vivid reminder of the sun’s power, urging us to take precautions during those peak hours!
| 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 | 11 | extreme | 10 min |
| 14:00 | 11 | extreme | 10 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, UV index levels exhibit significant seasonal changes, with high-risk months primarily from March to August. During this period, the UV index peaks, reaching extreme levels of 11 in June and July, where the burn time is as low as 10 minutes. Visitors and residents should take precautionary measures during these months, seeking shade and using SPF protection to reduce the risk of sunburn and long-term skin damage. Levels start to moderate again from September to November, allowing for safer sun exposure. January and December present the least risk, with moderate UV index levels of 3, where exposure can be as long as 30 minutes without immediate harm. It's essential for everyone to remain vigilant and adjust their sun safety practices based on the UV index throughout the seasons.
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 |
| Half Moon Bay | 3 | 5 | 8 | 9 | 10 | 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 |