Last updated: May 3, 2025
Understanding the UV Index is crucial for residents and visitors in Nuku'alofa, Tonga, where the sun's rays can be particularly intense. With a tropical Af climate, Nuku'alofa experiences significant UV exposure, especially during midday when levels soar to 9. Being aware of UV levels is more than just a precaution; it plays an essential role in sunburn prevention and maintaining long-term skin health. Whether you’re spending a day at the beach or exploring the lush landscapes, knowing when to seek shade and apply sunscreen can help safeguard your skin against harmful effects. Stay informed and enjoy the sun safely!
Starting your day early, the UV Index remains low, peaking at 1 between 07:00 and 08:00. As the day unfolds, the intensity gradually rises, hitting 2 by 09:00. However, the real surge occurs around 11:00, where the index escalates to 7, and reaches its zenith at 12:00 and 13:00 with a striking 9. This is the time to bask under the sun's rays but remember to stay protected! The afternoon sees a gradual decline, dropping to 5 by 15:00, and tapering off to 2 by 16:00. As the sun sets, the UV exposure diminishes, returning to a safe 1 by 17:00, and finally settling at 0 after 19:00. Plan your outdoor activities accordingly to maximize your enjoyment while staying safe!
| 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 | 5 | moderate | 30 min |
| 11:00 | 7 | high | 25 min |
| 12:00 | 9 | very high | 15 min |
| 13:00 | 9 | very high | 15 min |
| 14:00 | 7 | high | 25 min |
| 15:00 | 5 | moderate | 30 min |
| 16:00 | 2 | low | 45 min |
| 17:00 | 1 | low | 45 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 0 | low | 45 min |
The UV Index experiences significant seasonal variation, with the highest levels occurring from January to April, where the index reaches extreme levels (15-16) and a burn time of only 10 minutes. November and December also present extreme UV conditions. May marks a transition to very high levels (UV Index 9), with a burn time extending to 15 minutes, while June to August see a decrease in UV intensity yet maintain very high levels, particularly in July and August. As September through October approach extreme levels again, it’s crucial for residents and visitors to take precautions year-round. Sunscreen, protective clothing, and limited sun exposure during peak hours (10 AM to 4 PM) are highly advised, especially during the high-risk months of January to April and September to November.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Nuku'alofa | 16 | 15 | 14 | 11 | 9 | 7 | 8 | 10 | 11 | 13 | 15 | 16 |
| Tatakamotonga UVI | 16 | 15 | 14 | 11 | 9 | 7 | 8 | 10 | 11 | 13 | 15 | 16 |
| Haveluloto UVI | 16 | 15 | 14 | 11 | 9 | 7 | 8 | 10 | 11 | 13 | 15 | 16 |
| Lapaha UVI | 16 | 15 | 14 | 11 | 9 | 7 | 8 | 10 | 11 | 13 | 15 | 16 |
| Neiafu UVI | 16 | 16 | 15 | 12 | 9 | 7 | 8 | 11 | 12 | 14 | 15 | 16 |