Last updated: July 2, 2025
In Ottawa, Canada, staying informed about the UV Index is crucial for safeguarding your skin and overall health. With sunburn prevention and long-term skin health at stake, understanding UV levels helps residents make informed decisions about sun exposure, especially during peak hours. Ottawa's Dfb climate, characterized by its warm summers and snowy winters, presents unique challenges regarding UV risks. During the summer months, UV levels can soar, often reaching a peak of 8 around midday, making it essential to monitor the UV Index and take necessary precautions to enjoy the sun safely.
The UV Index throughout the day presents a clear and vigorous pattern of intensity. As the sun rises at 07:00, the index starts at a gentle 1, indicating minimal risk. By 08:00, it climbs to 2, still in the low range, but things escalate quickly; by 09:00, it reaches 3. The sun's power peaks astonishingly at 12:00, hitting a maximum of 8, which signifies a high risk for unprotected skin. This intense exposure persists until 14:00, before gradually tapering off through the afternoon. By 15:00, the index drops to 7, then diminishes further to 5 at 16:00, and continues to decline into the evening hours, settling back down to 1 by 19:00. Those planning outdoor activities during the midday hours should take care to protect themselves from the sun’s powerful rays!
| 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 | 7 | 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 |
The UV Index varies significantly throughout the year, reflecting notable seasonal changes in sun exposure. From January to March, UV levels remain relatively low to moderate, with a maximum index of 5 in March, granting burn times of up to 45 minutes. However, by April, the UV Index spikes to 8, marking the beginning of high-risk months that persist through August, where it reaches a peak of 9. During these critical summer months, burn times drastically shorten to just 15 minutes. As fall approaches in September, the index decreases to 7 but remains a significant high-risk month, with burn time extending to 25 minutes. Moving into winter, both November and December see a return to moderate UV levels, with indices of 3 and 2 respectively, allowing for burn times of 30 to 45 minutes. Visitors and residents should take extra precautions from April to August, utilizing sunscreen, wearing protective clothing, and seeking shade during peak sun hours to mitigate the risks of overexposure.
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 | 2 | 4 | 5 | 8 | 9 | 9 | 8 | 8 | 7 | 5 | 3 | 2 |
| Toronto UVI | 2 | 4 | 5 | 8 | 9 | 9 | 9 | 9 | 7 | 5 | 3 | 2 |