Last updated: May 3, 2025
Understanding the UV Index is crucial for residents of Fountain Valley, California, where sunny days and mild temperatures can lead to significant ultraviolet exposure. As a BSk climate zone, this region experiences varying UV levels throughout the day, peaking at 10 between 12:00 PM and 1:00 PM. Being aware of these UV index levels is essential for sunburn prevention and maintaining overall skin health. By learning to interpret the UV Index, you can better protect yourself and your loved ones from harmful effects such as skin damage and increased risk of skin cancer. Don't let a beautiful day catch you off guard—stay informed and enjoy the sun safely!
The UV Index throughout the day presents a clear escalation and decline in sun exposure risk. Starting at a mild level 1 at 7:00 AM, it gradually climbs to a notable level 10 by noon, indicating peak midday sunlight intensity. The zenith occurs between 12:00 PM and 1:00 PM, where the index remains at 10, necessitating protective measures against harmful UV rays. As the afternoon progresses, the UV Index begins to taper off, dipping to level 7 by 3:00 PM and eventually returning to level 1 by 7:00 PM. To ensure skin health and safety, sun protection is essential during those high-risk hours around midday!
| 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 | 10 | very high | 15 min |
| 14:00 | 9 | very high | 15 min |
| 15:00 | 7 | high | 25 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, UV Index levels fluctuate significantly, reflecting seasonal changes in sun exposure. January and December exhibit moderate UV levels (Index 4), with a burn time of 30 minutes. As spring arrives, February escalates to a high UV Index of 6 with a reduced burn time of 25 minutes. The risk peaks in March and April, hitting a very high UV Index of 8 and 10 respectively, with critical burn times of just 15 minutes. The summer months of June and July show the highest UV Index at 11, categorized as extreme, where even a brief 10-minute exposure can lead to burns. Although August and September remain very high, it’s crucial to remain vigilant. As UV levels taper off in October and November, a moderate level of risk is present again. Residents and visitors are advised to protect themselves with sunscreen, hats, and sunglasses, especially from March to September when UV exposure can be particularly harmful.
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 |
| Fountain Valley | 4 | 6 | 8 | 10 | 10 | 11 | 11 | 10 | 10 | 7 | 5 | 4 |
| Houston UVI | 5 | 8 | 9 | 11 | 11 | 12 | 12 | 11 | 10 | 9 | 7 | 5 |