Last updated: June 2, 2025
In Katwijk aan den Rijn, being aware of the UV Index is crucial for safeguarding your skin against potential harm from sun exposure. Understanding local UV levels not only helps in preventing painful sunburns but also plays a significant role in promoting long-term skin health. Given Katwijk's temperate oceanic climate, residents and visitors should be particularly mindful of the sun’s intensity, especially during peak hours when the UV Index can reach levels of 8 from late morning to early afternoon. Protect yourself and enjoy the sunny days while minimizing your risk!
The UV Index today begins on a gentle note, peaking at just 1 during the early hours of 07:00 and 08:00. As the sun rises higher, it takes a significant leap to 3 by 09:00 and reaches a moderate 4 by 10:00. The sun's intensity climbs to a robust 6 at 11:00, before hitting its zenith at a powerful 8 from 13:00 to 14:00. After this peak, the UV index gradually descends, softening to 7 at 15:00, and continuing down to 4 by 17:00. As the day winds down, conditions remain mild with readings of 3 at 18:00 and finally settling at 2 by 19:00. It's an excellent reminder to stay sun-safe during those prime hours!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 1 | low | 45 min |
| 09:00 | 3 | moderate | 30 min |
| 10:00 | 4 | moderate | 30 min |
| 11:00 | 6 | high | 25 min |
| 12:00 | 7 | high | 25 min |
| 13:00 | 8 | very high | 15 min |
| 14:00 | 8 | very high | 15 min |
| 15:00 | 7 | high | 25 min |
| 16:00 | 6 | high | 25 min |
| 17:00 | 4 | moderate | 30 min |
| 18:00 | 3 | moderate | 30 min |
| 19:00 | 2 | low | 45 min |
Throughout the year, UV radiation levels fluctuate significantly, necessitating varying levels of sun protection. From January to February, the UV Index remains low (1-2), allowing for extended exposure times without burning, approximately 45 minutes. However, as spring approaches, the UV Index rises, reaching moderate levels (4-5) in March and April, where 30-minute burn times apply. The summer months of May through July present the highest risk, with UV Index values peaking at 8 and very high exposure categories, meaning that unprotected skin can burn in just 15 minutes. August sees a slight decrease, but still maintains a high UV Index of 7, with a burn time of 25 minutes. In contrast, September to October return to moderate levels, allowing for 30-minute safe exposure, while November and December drop back down to low levels (1-2) with burn times of 45 minutes. Visitors and residents are strongly advised to take precautions during the high-risk months of May through July, utilizing sunscreen, protective clothing, and seeking shade to minimize UV exposure and safeguard skin health.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Amsterdam UVI | 1 | 2 | 4 | 5 | 7 | 8 | 8 | 7 | 5 | 3 | 2 | 1 |
| Katwijk aan den Rijn | 1 | 2 | 4 | 5 | 7 | 8 | 8 | 7 | 5 | 3 | 2 | 1 |
| Utrecht UVI | 1 | 2 | 4 | 5 | 7 | 8 | 8 | 7 | 5 | 3 | 2 | 1 |
| Rotterdam UVI | 1 | 2 | 4 | 5 | 7 | 8 | 8 | 7 | 5 | 3 | 2 | 1 |
| Eindhoven UVI | 1 | 2 | 4 | 5 | 7 | 8 | 8 | 7 | 5 | 3 | 2 | 1 |
| Tilburg UVI | 1 | 2 | 4 | 5 | 7 | 8 | 8 | 7 | 5 | 3 | 2 | 1 |