Last updated: June 2, 2025
Awareness of the UV Index is crucial in Hermosillo, Mexico, where the sun's rays can be particularly intense. Understanding UV levels not only helps in preventing sunburn but also plays a vital role in maintaining long-term skin health. With temperatures soaring in this BWh climate, residents and visitors alike face significant UV exposure risks, especially during peak hours when the index reaches a staggering 11. By staying informed about the daily UV Index, you can take the necessary precautions to enjoy the sun safely and protect your skin from potential damage.
At dawn, the UV Index begins its ascent with a mild 1 at 7:00 AM, gradually increasing to a moderate 2 by 8:00 AM. As the sun climbs higher, it reaches a noteworthy 5 at 9:00 AM, but the real intensity hits at 10:00 AM with a strong 7. By 11:00 AM, the UV levels soar to a peak of 10, continuing at an impressive 11 from 12:00 PM to 1:00 PM—the highest of the day. After this midday intensity, the numbers begin to wane, dropping to 10 at 2:00 PM, then to 8 at 3:00 PM. The afternoon cools off slightly, falling to 5 by 4:00 PM, and ultimately settling back to 3 by 5:00 PM. As the day draws to a close, the UV Index gently slips to 1 by 6:00 PM, and remains there until 7:00 PM, indicating a safe return to evening activities.
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 2 | low | 45 min |
| 09:00 | 5 | moderate | 30 min |
| 10:00 | 7 | high | 25 min |
| 11:00 | 10 | very high | 15 min |
| 12:00 | 11 | extreme | 10 min |
| 13:00 | 11 | extreme | 10 min |
| 14:00 | 10 | very high | 15 min |
| 15:00 | 8 | very high | 15 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, the UV Index shows significant seasonal variation, with the highest levels occurring from March to August. During these months, particularly April through July, the UV Index reaches a peak of 12 in July, categorized as extreme, allowing only a 10-minute burn time for unprotected skin. February also sees elevated levels with a high UV Index of 6. To ensure safety, visitors and residents should take extra precautions during the high-risk months of March, April, May, June, July, and August, when the risk of skin damage from sun exposure is at its highest. It is advisable to wear protective clothing, apply sunscreen, and seek shade during peak hours to minimize the risk of sunburn. As UV levels decrease in the fall and winter months, from September to December, individuals can enjoy more moderate exposure with indices dropping back to 4 or 5, indicating moderate risk and longer burn times of 30 minutes.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Hermosillo | 4 | 6 | 9 | 10 | 11 | 11 | 12 | 11 | 10 | 8 | 5 | 4 |
| Guadalajara UVI | 9 | 11 | 14 | 14 | 14 | 13 | 13 | 13 | 13 | 12 | 9 | 8 |
| Iztapalapa UVI | 10 | 12 | 14 | 15 | 14 | 14 | 14 | 14 | 14 | 12 | 10 | 8 |
| Ecatepec de Morelos UVI | 10 | 12 | 14 | 15 | 15 | 14 | 14 | 13 | 14 | 12 | 10 | 8 |
| Mexico City UVI | 10 | 12 | 14 | 15 | 15 | 14 | 14 | 13 | 14 | 12 | 10 | 8 |
| Puebla UVI | 10 | 12 | 14 | 15 | 15 | 15 | 15 | 14 | 14 | 13 | 10 | 9 |