Last updated: May 3, 2025
Understanding the UV Index is crucial for residents of Castroville, California, where sunny days are a staple of the Cfa climate. With UV levels soaring to a peak of 12 during midday hours, awareness can significantly help in preventing sunburn and maintaining long-term skin health. By keeping an eye on these levels, you can better protect yourself and your loved ones from harmful UV rays, particularly during the hottest parts of the day when risks are highest. Embrace the outdoors while staying informed about the UV Index to enjoy the beautiful Castroville sunshine safely!
As the sun rises, the UV Index starts at a mild 1 at 7:00 AM and remains low until 9:00 AM, where it climbs to 3. By 10:00 AM, the index accelerates to a moderate 5, but it’s at 11:00 AM that the heat intensifies, reaching 8. The peak occurs at 12:00 PM with a staggering value of 10, followed by the highest point of the day at 1:00 PM and 2:00 PM, where it maxes out at 12. After this peak, the index gradually declines: it drops to 10 by 3:00 PM and continues to decrease to 7 at 4:00 PM. By the late afternoon, the intensity wanes, falling to 5 at 5:00 PM and back down to 2 by 6:00 PM, before settling at 1 again as day turns to dusk by 7:00 PM. Remember to shield yourself during the midday hours when the UV radiation is at its most intense!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 1 | low | 45 min |
| 09:00 | 3 | moderate | 30 min |
| 10:00 | 5 | moderate | 30 min |
| 11:00 | 8 | very high | 15 min |
| 12:00 | 10 | very high | 15 min |
| 13:00 | 12 | extreme | 10 min |
| 14:00 | 12 | extreme | 10 min |
| 15:00 | 10 | very high | 15 min |
| 16:00 | 7 | high | 25 min |
| 17:00 | 5 | moderate | 30 min |
| 18:00 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, UV levels exhibit significant seasonal changes. January sees a moderate UV Index of 5, while February and March jump to 8 and 9, respectively, indicating very high exposure risks with short burn times of just 15 minutes. The peak months for UV exposure are from April to August, where the Index reaches an extreme level of 11 to 12, necessitating caution with a burn time of only 10 minutes. As the year progresses, UV levels decrease, but October remains notably high at 9, followed by November with a high category of 7. For visitors and residents alike, it is crucial to take protective measures during the high-risk months of April through September and remain vigilant, using sunscreen, wearing protective clothing, and seeking shade to minimize the risk of 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 |
| 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 |
| Castroville | 5 | 8 | 9 | 11 | 11 | 12 | 12 | 12 | 11 | 9 | 7 | 5 |