Last updated: June 2, 2025
Understanding the UV Index is crucial for residents and visitors in the City of London, UK, as it directly impacts skin health and sunburn prevention. With the city's Cfb climate, characterized by mild summers and longer daylight hours, Londoners may underestimate UV exposure, especially during peak hours when the UV Index can reach 8. Being aware of these levels allows you to take proactive measures, ensuring safe sun enjoyment while minimizing risks associated with harmful UV radiation. Stay informed and protect your skin as you navigate the vibrant streets of London!
As the sun rises, the UV Index begins its steady climb, starting from a gentle 1 at 7:00 AM. By 10:00 AM, it reaches 5, signaling an increase in UV exposure. The peak occurs at 12:00 PM, hitting a robust 8, where caution is advised, especially for outdoor activities. The intensity remains high at 8 from 1:00 PM to 2:00 PM, encouraging sun protection measures. As the afternoon progresses, the index gradually declines to 6 at 3:00 PM, then further to 3 by 5:00 PM. Finally, as the day winds down, the UV Index settles at 1 by 7:00 PM, reflecting a much safer environment for evening activities. Enjoy the sun, but remember to protect your skin during those peak hours!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 2 | low | 45 min |
| 09:00 | 4 | moderate | 30 min |
| 10:00 | 5 | moderate | 30 min |
| 11:00 | 7 | high | 25 min |
| 12:00 | 8 | very high | 15 min |
| 13:00 | 8 | very high | 15 min |
| 14:00 | 8 | very high | 15 min |
| 15:00 | 6 | high | 25 min |
| 16:00 | 5 | moderate | 30 min |
| 17:00 | 3 | moderate | 30 min |
| 18:00 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, UV exposure varies significantly, with notable increases during the spring and summer months. From January to February, the UV Index remains low (1-2), allowing for safer outdoor activities with a burn time of 45 minutes. As we progress into March and April, the levels rise to a moderate range (4-5), reducing burn time to 30 minutes. The high-risk months of May through August see a dramatic increase, with UV Index values reaching 7-8 (high to very high), which significantly shortens burn time to 15-25 minutes. Finally, from September to October, the risk decreases as the UV Index drops to moderate levels (4-6), returning to safer exposure times. Visitors and residents are advised to take precautions during high-risk months by wearing sunscreen, protective clothing, and seeking shade, especially during midday hours, to minimize the risk of skin damage.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 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 |
| City of London | 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 |