Last updated: May 3, 2025
Understanding the UV Index is crucial for the residents of Derry, United Kingdom, as it plays a vital role in protecting your skin from harmful ultraviolet rays. With the potential for sunburn and long-term skin health issues, being aware of UV levels can help you take essential precautions when enjoying the outdoors. Derry's Cfb climate offers a unique blend of moderate weather, but as UV exposure can be deceptive, particularly during peak hours—where levels can reach up to 6 from 12 PM to 3 PM—staying informed about the UV Index can ensure you enjoy the beauty of your surroundings safely.
The day's UV index begins low, starting at a mere 1 at 7:00 AM. As the sun rises higher, it gradually increases, peaking at 6 from 12:00 PM to 3:00 PM, indicating a moderate to high risk of harm from unprotected sun exposure during these hours. The index then starts to wane, falling back to 2 by 6:00 PM and closing the day at 1 by 7:00 PM. For sunseekers, the midday hours are the most critical, urging caution and protection to enjoy the vibrant outdoors safely.
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 2 | low | 45 min |
| 09:00 | 2 | low | 45 min |
| 10:00 | 4 | moderate | 30 min |
| 11:00 | 5 | moderate | 30 min |
| 12:00 | 6 | high | 25 min |
| 13:00 | 6 | high | 25 min |
| 14:00 | 6 | high | 25 min |
| 15:00 | 6 | high | 25 min |
| 16:00 | 4 | moderate | 30 min |
| 17:00 | 3 | moderate | 30 min |
| 18:00 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, the UV Index exhibits notable seasonal changes that reflect shifts in sun exposure. January and February are considered low risk months, with an index of 1-2 and a burn time of 45 minutes. However, as spring approaches, March and April move into the moderate category with an index of 4-5 and a decreased burn time of 30 minutes. The risk escalates significantly in May and June, reaching high (UV Index 6) and very high levels (UV Index 8), with just 15 minutes of unprotected exposure leading to potential skin damage. July continues this trend with similar UV intensity. In August, the index slightly lowers to 7, but still maintains a high risk level. The fall months of September and October see a return to moderate conditions with still significant burn times of 30 minutes. Finally, November and December again present low risk, echoing the start of the year. To ensure safety, it is essential for visitors and residents to be vigilant, especially during the high-risk months of May through August, by using sun protection measures like sunscreen, hats, and protective clothing when outdoors.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Derry | 1 | 2 | 4 | 5 | 6 | 8 | 8 | 7 | 5 | 3 | 2 | 1 |
| Liverpool UVI | 1 | 2 | 3 | 5 | 7 | 8 | 8 | 7 | 5 | 3 | 2 | 1 |
| Sheffield UVI | 1 | 2 | 4 | 5 | 7 | 8 | 8 | 7 | 5 | 4 | 2 | 1 |
| Birmingham UVI | 1 | 2 | 4 | 5 | 7 | 8 | 8 | 7 | 6 | 4 | 2 | 1 |
| London UVI | 1 | 2 | 4 | 5 | 7 | 8 | 8 | 7 | 6 | 4 | 2 | 1 |
| Bristol UVI | 1 | 2 | 4 | 5 | 7 | 8 | 8 | 7 | 6 | 4 | 2 | 1 |