Last updated: July 2, 2025
In Lahti, Finland, staying informed about the UV Index is crucial for protecting your skin and overall health. Understanding UV levels is essential for preventing sunburn and long-term skin damage, especially during the sunniest parts of the day. Lahti’s Dfb climate brings variable weather, but when the sun shines, UV exposure can peak, particularly between 11:00 AM and 3:00 PM, reaching levels of 6. By keeping an eye on the UV Index, you can enjoy outdoor activities safely while minimizing the risks associated with sun exposure.
At dawn, the UV Index begins its gentle ascent, peaking at 1 by 7:00 AM. As the sun rises higher, the index climbs steadily: reaching 2 at 8:00 AM, it hits 3 by 9:00 AM. The golden hour of 10:00 AM is marked with a 4, and by 11:00 AM, it surges to 5, indicating moderate exposure. The midday sun showcases its strength, with a maximum of 6 between 12:00 PM and 3:00 PM – a clear signal for sun protection! As the afternoon wanes, the index gradually declines, dropping to 3 at 5:00 PM, and finally tapering off to 1 by 7:00 PM, as the sun sets. Remember, during those peak hours, staying protected is essential!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 2 | low | 45 min |
| 09:00 | 3 | moderate | 30 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 | 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 a notable increase during the warmer months. January to February experience low UV levels (Index 1), allowing for a more extended burn time of 45 minutes. As spring arrives in March, the UV Index rises to 3, indicating a moderate risk, necessitating caution with an exposure limit of 30 minutes. The summer months, especially June and July, present a high-risk scenario with indexes reaching 6 and 7 respectively, where it's advised to limit sun exposure to 25 minutes to prevent skin damage. August sees a decrease to a moderate level, while September returns to a more manageable 3. As autumn transitions into winter, UV levels decrease again to low (Indexes of 1 and 2), allowing for longer safe exposure times of 45 minutes. Residents and visitors are encouraged to remain vigilant during June to July, using sunscreen and protective clothing to safeguard against harmful UV radiation.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Tampere UVI | 1 | 1 | 3 | 4 | 5 | 6 | 6 | 5 | 3 | 2 | 1 | 1 |
| Lahti | 1 | 1 | 3 | 4 | 5 | 6 | 7 | 5 | 3 | 2 | 1 | 1 |
| Vantaa UVI | 1 | 1 | 3 | 4 | 5 | 7 | 7 | 5 | 4 | 2 | 1 | 1 |
| Espoo UVI | 1 | 1 | 3 | 4 | 5 | 7 | 7 | 5 | 4 | 2 | 1 | 1 |
| Helsinki UVI | 1 | 1 | 3 | 4 | 5 | 7 | 7 | 5 | 4 | 2 | 1 | 1 |
| Turku UVI | 1 | 2 | 3 | 4 | 5 | 7 | 7 | 5 | 4 | 2 | 1 | 1 |