Last updated: August 1, 2025
Understanding the UV Index is crucial for residents of Shahriar, Iran, where ample sunshine is a hallmark of the Csa climate. With midday UV levels soaring to a significant 11, awareness of these metrics not only aids in the prevention of painful sunburn but is vital for long-term skin health. As the sun's rays become more intense throughout the day, knowing when to seek shade or protect your skin can make all the difference. In Shahriar, where outdoor activities thrive, understanding UV exposure risks ensures that you enjoy the sun safely and responsibly.
As the sun rises, the UV Index begins its ascent, starting modestly at 1 by 7:00 AM. By 9:00 AM, the intensity ramps up to 5, signaling a gentle warning for sun-sensitive activities. The peak arrives between 11:00 AM and 1:00 PM, where the UV Index reaches a robust 11, indicating a high risk of harm from unprotected sun exposure. After this zenith, the numbers gradually decline, dropping to 7 by 3:00 PM, and later sinking back to a lowly 1 by 6:00 PM. This hourly dance of UV radiation reminds us to stay vigilant during the brightest hours of the day, ensuring we protect our skin while enjoying the sunshine.
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 2 | low | 45 min |
| 09:00 | 4 | moderate | 30 min |
| 10:00 | 6 | high | 25 min |
| 11:00 | 9 | very high | 15 min |
| 12:00 | 10 | very high | 15 min |
| 13:00 | 10 | very high | 15 min |
| 14:00 | 9 | very high | 15 min |
| 15:00 | 7 | high | 25 min |
| 16:00 | 4 | moderate | 30 min |
| 17:00 | 2 | low | 45 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 1 | low | 45 min |
The UV Index varies significantly throughout the year, showing distinct seasonal changes in sun exposure risk. January and February have a moderate UV Index of 4 and 5, allowing for about 30 minutes of sun exposure without burning. As we move into March and April, the UV Index climbs sharply to 8 and 9, categorized as very high, with burn times decreasing to 15 minutes. The peak of sun intensity occurs in May and June, where an extreme UV Index of 12 warrants a 10-minute exposure limit to prevent skin damage. July sees a slight decrease to 11, while August and September remain high at 10. In October, the risk lowers to a high index of 7, allowing for 25 minutes of safe exposure. Finally, November and December return to moderate levels of 4 and 3, with safer burn times of 30 minutes. Residents and visitors should take extra precautions during the high-risk months of March through September, utilizing sunscreen, protective clothing, and seeking shade during peak hours.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Shahriar | 4 | 5 | 8 | 9 | 12 | 12 | 11 | 10 | 10 | 7 | 4 | 3 |
| Karaj UVI | 4 | 5 | 8 | 9 | 12 | 12 | 11 | 10 | 10 | 7 | 4 | 3 |
| Mashhad UVI | 4 | 5 | 8 | 10 | 12 | 12 | 12 | 11 | 10 | 7 | 4 | 3 |
| Tehran UVI | 4 | 6 | 8 | 9 | 13 | 12 | 11 | 10 | 10 | 7 | 5 | 3 |
| Tabriz UVI | 4 | 5 | 9 | 10 | 12 | 12 | 12 | 11 | 9 | 7 | 4 | 3 |
| Isfahan UVI | 5 | 7 | 10 | 10 | 13 | 13 | 12 | 11 | 10 | 9 | 6 | 4 |