Last updated: August 1, 2025
In Waterloo, Canada, being aware of the UV Index is crucial for protecting your skin and maintaining overall health. Understanding UV levels helps prevent sunburn and reduces the risk of long-term skin damage, making it essential for outdoor enthusiasts and sun-seekers alike. With Waterloo's Dfb climate, characterized by warm summers and occasional high UV exposure, knowing the daily UV index can help you enjoy the sun safely. During peak hours, the UV Index can reach levels as high as 9, prompting the need for proactive sun protection measures to keep your skin safe while soaking up the summer rays.
The UV Index for today reveals a dynamic and evolving exposure to UV radiation. Starting at 07:00 AM with a low of 1, the index gradually climbs throughout the morning, reaching 5 by 10:00 AM. As we approach midday, the index peaks at a sizzling 9 around 1:00 PM. Afterward, it gradually declines, dropping to 6 by 3:00 PM, and further to a gentle 2 by 6:00 PM. This progression highlights the importance of sun safety, especially during the peak hours of 11:00 AM to 1:00 PM, when UV levels are at their highest. Stay protected!
| 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 | 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 | 4 | moderate | 30 min |
| 17:00 | 3 | moderate | 30 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, UV exposure varies significantly, with the highest risk occurring during the summer months of May through August. During this period, the UV Index reaches a peak of 9, classified as very high, with a minimal burn time of just 15 minutes. Conversely, the UV Index is at its lowest in January and December at 2, indicating a low risk of harm from sun exposure, allowing for a burn time of 45 minutes. April and September mark transitional months where the UV Index is high at 7, prompting caution with a burn time of 25 minutes. To protect against harmful UV radiation, it is crucial for both visitors and residents to take appropriate precautions, particularly from May to August, such as wearing sunscreen, protective clothing, and seeking shade during peak sun hours.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Edmonton UVI | 2 | 3 | 5 | 6 | 7 | 7 | 8 | 7 | 6 | 4 | 2 | 1 |
| Calgary UVI | 2 | 3 | 4 | 6 | 8 | 8 | 9 | 8 | 7 | 4 | 2 | 1 |
| Montreal UVI | 2 | 4 | 5 | 7 | 9 | 9 | 8 | 8 | 7 | 5 | 3 | 2 |
| Ottawa UVI | 2 | 4 | 5 | 8 | 9 | 9 | 8 | 8 | 7 | 5 | 3 | 2 |
| Waterloo | 2 | 4 | 5 | 7 | 9 | 9 | 9 | 8 | 7 | 5 | 3 | 2 |
| Toronto UVI | 2 | 4 | 5 | 8 | 9 | 9 | 9 | 9 | 7 | 5 | 3 | 2 |