Last updated: May 3, 2025
Understanding the UV Index is crucial for the residents of Mason City, as it plays a significant role in protecting your skin health and preventing sunburn. With a climate classified as Dfa, the city experiences varying UV levels, particularly peaking between 12 PM and 2 PM when risks are at their highest with indices reaching 9. Being aware of these levels can help you take essential precautions during sunny days, ensuring you enjoy the outdoors safely while minimizing the chances of skin damage. Whether you're planning a day out at the park or simply running errands, knowing the UV Index is key to safeguarding your skin.
At 07:00, the UV Index begins at a mild 1, perfect for a leisurely morning stroll. As the sun rises higher, it gradually climbs to 2 by 08:00 and reaches 3 at 09:00. The intensity really kicks in at 10:00, jumping to 5, and soars to its peak of 9 by 13:00. This high exposure continues through 14:00, making midday the most crucial time for sun protection. As the afternoon wanes, the index dips to 7 at 15:00, then continues to decline to 5 at 16:00 and settles back to 3 by 17:00. The evening brings relief with a return to 2 by 18:00 and finally drops to 1 at 19:00. Make sure to stay protected 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 | 5 | moderate | 30 min |
| 11:00 | 7 | high | 25 min |
| 12:00 | 8 | very high | 15 min |
| 13:00 | 9 | 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 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, the UV Index demonstrates significant seasonal fluctuations, with high-risk months typically occurring from April to September. In April, the UV Index escalates to 8, indicating very high exposure risks, and remains elevated through May (9) and June (11), where it reaches an extreme level. July (10) and August (9) continue to present very high risks, before tapering off in September (8). As a precaution, visitors and residents should take protective measures, especially during these peak months, by seeking shade, wearing protective clothing, and applying sunscreen frequently. In contrast, the UV Index drops to a moderate level (3-5) from October to March, allowing for safer outdoor activities during this period.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Mason City | 3 | 5 | 5 | 8 | 9 | 11 | 10 | 9 | 8 | 5 | 3 | 3 |
| 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 |