Last updated: July 2, 2025
Understanding the UV Index is crucial for residents and visitors in Toronto, Canada, where the vibrant summer sun can hide hidden dangers. With skin cancer rates on the rise, being aware of UV levels can help you take proactive steps to prevent sunburns and promote overall skin health. Toronto's Dfb climate features distinct seasons, but during the warmer months, UV exposure can peak dramatically, especially between 11 AM and 3 PM when levels soar to 8 and 9—high enough to warrant caution. By staying informed about the daily UV Index, you can enjoy the outdoors safely while protecting your skin from harmful rays.
As the sun rises, the UV Index begins its ascent, starting at a mild 1 at 07:00. By 08:00, it climbs to a 2, indicating a low risk of harm from unprotected sun exposure. However, from 09:00 onwards, the intensity builds, peaking at 9 between 13:00 and 14:00—a time when precautions are essential to protect skin from damage. The afternoon hours see a slight decrease, dropping to 8 at 15:00 and further declining to 4 by 17:00. As the sun sets, the UV Index falls back down to 1 by 19:00, marking a return to safer levels. Stay vigilant during those midday hours to enjoy the sunshine while keeping your skin healthy!
| 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 | 9 | very high | 15 min |
| 14:00 | 9 | very high | 15 min |
| 15:00 | 8 | very high | 15 min |
| 16:00 | 6 | high | 25 min |
| 17:00 | 4 | moderate | 30 min |
| 18:00 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, UV exposure varies significantly, with the highest risk months occurring from April to August, where the UV Index consistently reaches 9, classifying it as very high. During these months, the burn time is a mere 15 minutes, emphasizing the need for caution. As winter approaches, the UV Index decreases, dropping to 2 in January and December, indicating a low risk of UV exposure, while February and March see moderate levels with indices of 4 and 5, respectively. Visitors and residents should prioritize protective measures such as using sunscreen, wearing protective clothing, and seeking shade, especially in the spring and summer months, when the sun's intensity is at its peak. Staying informed and alert can help mitigate the risks associated with UV exposure year-round.
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 |
| Toronto | 2 | 4 | 5 | 8 | 9 | 9 | 9 | 9 | 7 | 5 | 3 | 2 |