Last updated: June 2, 2025
Understanding the UV Index is crucial for residents of Houston, Texas, where the sun's rays can be both powerful and harmful. Awareness of UV levels is essential not only for preventing painful sunburns but also for protecting long-term skin health and reducing the risk of skin cancer. With Houston's Dfc climate bringing warm temperatures and abundant sunlight, the UV Index can rise particularly high, peaking at a level of 6 around mid-afternoon. This highlights the importance of taking protective measures during those hours when UV exposure poses greater risks. Stay informed and take steps to shield yourself from the sun's potentially damaging effects!
As the day begins, the UV Index starts at a very low level of 1 at 07:00 and 08:00, urging early risers to enjoy the gentle sunlight safely. By 09:00, it climbs to 2, indicating a slight increase in UV exposure. As the hours progress, the sun's intensity peaks at 12:00 and 13:00, reaching a maximum of 5—perfect for those looking to soak up some rays but remember to apply sunscreen! The afternoon marks the highest UV risks, peaking at 14:00 with a UV index of 6, before gradually declining to 4 by 17:00. As evening approaches, the index decrements back down to 2 by 19:00, offering a safer environment for those who may be out and about. Stay sun-smart and enjoy the daylight hours wisely!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 1 | low | 45 min |
| 09:00 | 2 | low | 45 min |
| 10:00 | 3 | moderate | 30 min |
| 11:00 | 4 | moderate | 30 min |
| 12:00 | 5 | moderate | 30 min |
| 13:00 | 5 | moderate | 30 min |
| 14:00 | 6 | high | 25 min |
| 15:00 | 5 | moderate | 30 min |
| 16:00 | 5 | moderate | 30 min |
| 17:00 | 4 | moderate | 30 min |
| 18:00 | 3 | moderate | 30 min |
| 19:00 | 2 | low | 45 min |
Throughout the year, seasonal UV changes indicate varying levels of sun exposure risk. From January to February, the UV Index remains low (1), allowing for a safe exposure time of up to 45 minutes. As we transition into March, the index rises to 3, indicating a moderate risk, reducing the safe exposure time to 30 minutes. The risk peaks in May through July with high UV levels (6 and 7), necessitating an exposure limit of just 25 minutes. In August and September, the index returns to moderate levels (5 and 4), allowing for a 30-minute burn time again. As the year concludes, October through December sees a return to low UV levels (1-2), with a safe exposure limit of 45 minutes. Residents and visitors should be particularly cautious during the high-risk months of May, June, and July, applying sunscreen and seeking shade to mitigate potential sun damage.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Houston | 1 | 1 | 3 | 4 | 6 | 6 | 7 | 5 | 4 | 2 | 1 | 1 |
| 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 |