Last updated: July 2, 2025
Understanding the UV Index is crucial for residents of Lowell, United States, as it provides vital information about sun exposure and its potential risks. Knowledge of UV levels is essential for preventing sunburn and protecting skin health, particularly during the peak summer months when the UV Index can soar. Lowell's humid subtropical climate (Cfa) contributes to significant UV exposure, especially around midday when indices reach a maximum of 11, indicating a high risk of harm from unprotected sun exposure. Staying informed about these levels empowers you to enjoy the outdoors safely while prioritizing your skin's health.
Throughout the day, the UV Index peaks dramatically, starting at a mild 1 in the early morning at 7:00 AM and 8:00 AM. As the sun climbs higher, 9:00 AM sees a moderate increase to 3, but it’s not until 10:00 AM that the UV Index hits 5, signaling a need for some sun protection. The intensity truly soars at 11:00 AM, reaching 7, and by 12:00 PM it escalates to a striking 9, before soaring to its maximum of 11 at 1:00 PM. After the zenith, the index gradually recedes to 10 at 2:00 PM, and then descends slowly: 9 at 3:00 PM, 7 at 4:00 PM, and down to 4 by 5:00 PM. The evening brings relief, as the UV Index dips to 2 at 6:00 PM and finally settles back to 1 as the sun sets at 7:00 PM. Ensure to stay protected during those peak hours!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 1 | low | 45 min |
| 09:00 | 3 | moderate | 30 min |
| 10:00 | 5 | moderate | 30 min |
| 11:00 | 7 | high | 25 min |
| 12:00 | 9 | very high | 15 min |
| 13:00 | 11 | extreme | 10 min |
| 14:00 | 10 | very high | 15 min |
| 15:00 | 9 | very high | 15 min |
| 16:00 | 7 | 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 exhibits significant variations, with high-risk months occurring from March to August, where the index reaches very high to extreme levels. In March and April, the UV Index peaks at 10, and it escalates to 11 in June and July, indicating an urgent need for sun protection since the burn time drops to just 10 minutes during these months. The risk decreases in the fall and winter, with November and December showing moderate levels (UV Index of 5 and 3, respectively) and extended burn times of 30 minutes. To ensure safety, visitors and residents are advised to take extra precautions during the high-risk months by wearing sunscreen, protective clothing, and seeking shade, while enjoying outdoor activities to minimize the risk of skin damage.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 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 |
| Lowell | 4 | 6 | 8 | 10 | 10 | 11 | 11 | 10 | 9 | 8 | 5 | 3 |
| Houston UVI | 5 | 8 | 9 | 11 | 11 | 12 | 12 | 11 | 10 | 9 | 7 | 5 |