Last updated: July 2, 2025
Understanding the UV Index is essential for the residents of Yen Lap, Vietnam, especially given its humid subtropical climate (Cwa) that can significantly elevate UV exposure levels throughout the day. Awareness of UV levels is critical for effective sunburn prevention and safeguarding skin health, as prolonged exposure can lead to various skin issues. With peak UV Index values soaring to 14 during midday, it's crucial for locals and visitors alike to be mindful of their time outdoors, taking necessary precautions to enjoy the sun safely while minimizing the risks associated with high UV radiation.
At dawn, the UV Index starts softly at 2 by 07:00, suggesting a low risk for sun exposure. As the morning progresses, it escalates to 4 by 08:00 and reaches 7 at 09:00, indicating a moderate level of sun intensity. The day peaks with an impressive 14 at 12:00, where sun safety becomes crucial as the risk is rated high. Afternoon hours see a gradual decline from 13 at 13:00 down to 10 by 14:00, before dropping further to 6 at 15:00. As the sun begins to set, the UV Index dwindles to 3 by 16:00, and finally settles at 1 by 17:00 and 18:00, with a complete drop to 0 by 19:00, signaling that the sun's rays are no longer a concern. Always remember to protect your skin during those high UV periods!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 2 | low | 45 min |
| 08:00 | 4 | moderate | 30 min |
| 09:00 | 7 | high | 25 min |
| 10:00 | 10 | very high | 15 min |
| 11:00 | 13 | extreme | 10 min |
| 12:00 | 14 | extreme | 10 min |
| 13:00 | 13 | extreme | 10 min |
| 14:00 | 10 | very high | 15 min |
| 15:00 | 6 | high | 25 min |
| 16:00 | 3 | moderate | 30 min |
| 17:00 | 1 | low | 45 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 0 | low | 45 min |
Throughout the year, UV exposure varies significantly, with the highest levels occurring between March and October. During this period, particularly from May to September, the UV Index reaches an extreme level of 14, indicating a burn time of just 10 minutes for unprotected skin. Notably, January and February also present very high UV levels, with an index of 8 and 10 respectively, but have a slightly longer burn time of 15 minutes. As a result, high-risk months for sun exposure include March, April, May, June, July, August, September, and October. Residents and visitors should exercise caution during these months by seeking shade, wearing protective clothing, and applying sunscreen to mitigate the risk of sunburn and long-term skin damage. In contrast, November and December feature lower UV levels, with burn times of 15 and 25 minutes respectively, providing a slight reprieve from intense sun exposure.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Hanoi UVI | 8 | 10 | 12 | 12 | 13 | 12 | 12 | 13 | 13 | 11 | 9 | 7 |
| Haiphong UVI | 8 | 10 | 12 | 13 | 12 | 13 | 13 | 13 | 13 | 11 | 9 | 7 |
| Yen Lap | 8 | 10 | 12 | 12 | 14 | 13 | 14 | 14 | 14 | 12 | 9 | 7 |
| Da Nang UVI | 10 | 12 | 14 | 15 | 14 | 13 | 14 | 14 | 13 | 12 | 10 | 9 |
| Ho Chi Minh City UVI | 10 | 13 | 15 | 14 | 14 | 12 | 13 | 14 | 13 | 13 | 11 | 10 |
| Bien Hoa UVI | 10 | 14 | 15 | 15 | 14 | 13 | 14 | 14 | 13 | 12 | 11 | 10 |