Last updated: July 2, 2025
Understanding the UV Index in Semarang, Indonesia is crucial for protecting your skin and overall health. With its tropical climate, Semarang experiences high levels of ultraviolet radiation, especially during midday hours when the UV Index peaks at 10. Being aware of these levels can significantly aid in sunburn prevention and maintaining long-term skin health. Whether you're enjoying outdoor activities or commuting, staying informed about UV exposure risks is essential in this vibrant city, ensuring you can revel in its beauty while keeping your skin safe from harmful rays.
The UV Index paints a vivid picture of a sun-drenched day, starting with a mild 1 at 07:00 and rapidly escalating to its peak. As the sun climbs higher, 08:00 sees it at 3, but by 09:00, it spikes to a brisk 6. The heat really intensifies around 10:00, where it hits 9, and reaches its zenith with a 10 at both 11:00 and 12:00. After this peak, a gradual decline begins; by 13:00, it's at 9, then falls to 6 by 14:00. The afternoon cools off with values of 3 at 15:00 and then plummets back to 1 at 16:00 and 17:00. As the sun sets, the UV Index drops to 0 by 18:00, marking the end of a fascinating solar journey for the day. Be sure to enjoy the sunshine, but don’t forget your sunscreen during those peak hours!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 3 | moderate | 30 min |
| 09:00 | 6 | high | 25 min |
| 10:00 | 9 | very high | 15 min |
| 11:00 | 10 | very high | 15 min |
| 12:00 | 10 | very high | 15 min |
| 13:00 | 9 | very high | 15 min |
| 14:00 | 6 | high | 25 min |
| 15:00 | 3 | moderate | 30 min |
| 16:00 | 1 | low | 45 min |
| 17:00 | 1 | low | 45 min |
| 18:00 | 0 | low | 45 min |
| 19:00 | 0 | low | 45 min |
Throughout the year, UV levels show significant variation, with the highest readings occurring in the winter and early spring months. From January to April, the UV Index remains in the extreme category, peaking at 15 in February and March, with a burn time of just 10 minutes. As we transition into the summer months, the UV Index decreases slightly, reaching a very high level of 10 in June and July, allowing for a burn time of 15 minutes. The UV levels then rise again into the extreme category by August, with a notable 12. The high-risk months for UV exposure are from January through April, where immediate protection is essential. Visitors and residents are strongly advised to take precautions, including wearing sunscreen, protective clothing, and seeking shade, especially during these peak months to reduce the risk of skin damage.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Surabaya UVI | 13 | 15 | 14 | 12 | 12 | 10 | 11 | 12 | 14 | 13 | 13 | 13 |
| Semarang | 14 | 15 | 15 | 13 | 12 | 10 | 10 | 12 | 13 | 14 | 14 | 13 |
| Bekasi UVI | 14 | 16 | 16 | 14 | 11 | 10 | 10 | 11 | 13 | 15 | 14 | 13 |
| Jakarta UVI | 14 | 16 | 16 | 14 | 11 | 10 | 10 | 11 | 13 | 15 | 14 | 13 |
| Medan UVI | 13 | 15 | 15 | 15 | 14 | 12 | 12 | 13 | 14 | 14 | 13 | 12 |
| Bandung UVI | 15 | 16 | 16 | 15 | 12 | 11 | 11 | 12 | 14 | 15 | 15 | 14 |