Last updated: May 3, 2025
Understanding the UV Index is essential for residents of Warrenton, United States, where the climate often warms up to a Cfa climate with plenty of sunshine. The UV Index provides crucial information about the strength of the sun's ultraviolet rays, helping you to prevent sunburn and protect your skin health. With peak UV levels reaching 11 around midday, it's vital to be aware of the risks associated with high UV exposure. Whether you're spending time outdoors during the summer months or enjoying Warrenton's pleasant climate year-round, keeping an eye on the UV Index can ensure that your time in the sun remains safe and enjoyable.
The UV Index throughout the day presents a clear picture of solar intensity. Starting at 1 at 07:00, it gradually climbs to a moderate 2 by 08:00. By 09:00, we see a slight increase to 3, but the real surge happens as the sun reaches its peak. At 10:00, the index hits 5, and by 11:00, it jumps to 8. The zenith occurs at 12:00, peaking at a formidable 10. The midday hours bring intense sun exposure, with 13:00 reaching an impressive 11 before slightly tapering off. From 14:00 to 15:00, it holds steady at 10 and 8, respectively, indicating the sun’s continued strength. As the evening approaches, the index begins to decline, dropping to 6 at 16:00, and further down to 3 by 17:00. Finally, the day winds down with 2 at 18:00 and returns to 1 by 19:00, emphasizing the importance of sun safety during those peak hours when the UV index is at its highest.
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 2 | 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 | 11 | extreme | 10 min |
| 14:00 | 10 | very high | 15 min |
| 15:00 | 8 | very high | 15 min |
| 16:00 | 6 | high | 25 min |
| 17:00 | 3 | moderate | 30 min |
| 18:00 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, UV index levels exhibit significant seasonal variations, indicating fluctuating sun exposure risks. The high-risk months typically occur from March to August, with peak UV levels recorded in May, June, and July, where the index reaches an extreme 11 and the burn time reduces to just 10 minutes. During this period, it is crucial for visitors and residents to take protective measures, such as wearing sunscreen with high SPF, donning protective clothing, and seeking shade during midday hours. As summer transitions into autumn, the UV index gradually declines; however, it remains at very high levels through September and October. By late fall and winter, the UV index decreases to moderate levels in November and December, making sun safety less critical, but still advisable. Staying aware of these seasonal changes can help everyone enjoy the outdoors safely.
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 |
| Warrenton | 3 | 6 | 7 | 10 | 11 | 11 | 11 | 10 | 9 | 8 | 5 | 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 |