Last updated: June 2, 2025
Understanding the UV Index is crucial for residents of Petersburg, United States, where the climate, categorized as Cfb, brings mild summers and varying UV exposure risks. Awareness of UV levels is vital not just for preventing painful sunburns but also for maintaining long-term skin health. With peak UV readings reaching up to 10 around midday, it's essential to stay informed about local UV conditions to protect yourself and your loved ones from harmful effects. By recognizing and responding to these levels, Petersburg residents can enjoy the outdoors safely while minimizing their risk of skin damage.
As the sun rises, the UV Index steadily climbs, beginning at a moderate 1 at 07:00. By 08:00, it reaches 2, indicating a slight rise in solar intensity. The index continues to peak dramatically, hitting a notable 6 by 10:00 and soaring to a maximum of 10 from 12:00 to 14:00, marking this time as the most intense period for UV exposure. As the afternoon wanes, the index begins to decline, dropping to 9 at 15:00, then gently falling to 4 by 17:00. Finally, as the day turns to dusk, the UV Index settles back to a safer 1 by 19:00. It's crucial to enjoy the sun wisely, particularly during those peak hours!
| 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 | 6 | high | 25 min |
| 11:00 | 8 | very high | 15 min |
| 12:00 | 10 | very high | 15 min |
| 13:00 | 10 | very high | 15 min |
| 14:00 | 10 | very high | 15 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 exposure varies significantly, with the highest risk months being April through September, when the UV Index consistently falls within the very high category (10) for most of this period. March marks a transition into high exposure (UV Index 7), while October sees a decrease back to high levels. The moderate exposure months are January, February, November, and December, where burn times are longer, allowing for more extended safe exposure, specifically 30 minutes in January, February, November, and December, and 25 minutes in October. To protect against UV radiation, it is essential for visitors and residents alike to adjust their sun safety practices during the high-risk months. This includes seeking shade, wearing protective clothing, applying sunscreen with a high SPF, and limiting sun exposure during peak hours.
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 |
| Petersburg | 3 | 5 | 7 | 10 | 10 | 10 | 10 | 10 | 8 | 7 | 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 |