Last updated: July 2, 2025
Understanding the UV Index in Houston is crucial for safeguarding your skin health and preventing sunburn. With its Dfa climate, Houston experiences high levels of UV radiation, especially during the summer months, making awareness of UV levels even more important. From a mid-morning peak of 10 at 1 PM to more moderate levels in the early morning and late afternoon, knowing when to seek shade or apply sunscreen can make all the difference. By staying informed about the UV Index, you can enjoy the sun safely while protecting your skin from potential damage!
The UV Index throughout the day paints a clear picture of sun intensity. Starting from a gentle 1 at 07:00, the UV levels gradually rise, peaking at an intense 10 by 13:00. This midday spike calls for caution as sun exposure increases significantly. As the afternoon progresses, from 14:00 to 15:00, the index slightly dips to 9 and 8, respectively, before gradually falling off to 6 at 16:00 and down to a mellow 1 by 19:00. For outdoor enthusiasts, the window between 11:00 and 13:00 is the time to enjoy the sun while remaining mindful of skin protection.
| 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 | 8 | very high | 15 min |
| 12:00 | 9 | very high | 15 min |
| 13:00 | 10 | very high | 15 min |
| 14:00 | 9 | very high | 15 min |
| 15:00 | 8 | 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, the UV Index shows significant seasonal changes that impact sun safety for residents and visitors. From April to September, the UV Index peaks, reaching levels as high as 10 in the summer months of June and July. This indicates a very high exposure category, with a reduced burn time of only 15 minutes during these months. Conversely, during the winter months of December through February, the UV Index is considerably lower, ranging from 2 to 4, with a burn time of 30 to 45 minutes. Therefore, visitors and residents should be especially cautious during the high-risk months of April to September, and take appropriate protective measures, such as wearing sunscreen, protective clothing, and seeking shade, to minimize their risk of UV exposure.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Houston | 3 | 4 | 5 | 8 | 9 | 10 | 10 | 9 | 8 | 5 | 3 | 2 |
| 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 |