Last updated: August 1, 2025
Understanding the UV Index is crucial for residents and visitors in Belfast, New Zealand, as it plays a key role in promoting skin health and preventing sunburn. With a Cfb climate, Belfast typically experiences moderate UV exposure, especially during the midday hours when the UV Index peaks at 2. Being aware of the UV levels can help you make informed decisions about sun protection, allowing you to enjoy the beautiful outdoors while safeguarding your skin. With a UV Index that ranges from 0 to 2 throughout the day, it’s essential to stay informed and proactive to minimize any potential risks associated with sun exposure.
The UV Index throughout the day reveals a gradual ascent as the sun climbs high in the sky. Starting at a maximum of 0 at 07:00, the index slowly advances to 1 from 08:00 to 10:00. By 11:00, it reaches 2, peaking at this level from 12:00 to 14:00, indicating a moderate risk for harm from unprotected sun exposure. As the afternoon wanes, the UV intensity begins to taper off, descending to 1 by 15:00 and then returning to 0 by 18:00. This hourly fluctuation emphasizes the importance of being sun-smart during those midday hours when the UV Index is at its peak.
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 1 | low | 45 min |
| 09:00 | 1 | low | 45 min |
| 10:00 | 2 | low | 45 min |
| 11:00 | 3 | moderate | 30 min |
| 12:00 | 3 | moderate | 30 min |
| 13:00 | 3 | moderate | 30 min |
| 14:00 | 3 | moderate | 30 min |
| 15:00 | 2 | low | 45 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, the UV Index demonstrates significant seasonal fluctuations, with the highest levels occurring during the winter months of January (13) and February (12), categorized as extreme with a rapid burn time of 10 minutes. The transition to spring sees a decrease, with March at 9 (very high) and April dropping to 6 (high). May marks a notable reduction to 3 (moderate) as temperatures warm up, continuing through the summer months of June and July where the index remains low at 2. As autumn approaches, the index rises again with October and November at 9 and 10 (very high), respectively, having burn times of just 15 minutes. Visitors and residents should exercise increased caution during the high-risk months of January, February, October, and November, ensuring proper sun protection measures such as sunscreen, hats, and protective clothing to minimize skin damage.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Belfast | 13 | 12 | 9 | 6 | 3 | 2 | 2 | 3 | 5 | 9 | 10 | 12 |
| Christchurch UVI | 13 | 12 | 9 | 6 | 3 | 2 | 2 | 3 | 5 | 9 | 10 | 12 |
| Wellington UVI | 13 | 13 | 9 | 7 | 4 | 2 | 2 | 4 | 6 | 9 | 10 | 13 |
| Hamilton UVI | 14 | 14 | 10 | 7 | 4 | 3 | 3 | 5 | 7 | 10 | 11 | 13 |
| Manukau City UVI | 14 | 14 | 10 | 7 | 4 | 3 | 3 | 5 | 7 | 10 | 11 | 13 |
| Auckland UVI | 14 | 14 | 10 | 7 | 4 | 3 | 3 | 5 | 7 | 10 | 11 | 13 |