Last updated: May 3, 2025
Understanding the UV Index is crucial for residents of Saint John, Canada, where the climate can heighten exposure to harmful ultraviolet radiation. As UV levels can significantly impact skin health and increase the risk of sunburn, being aware of daily fluctuations is essential for safe outdoor activities. With the region's typical climate classified as Dfb, residents often enjoy sunny summers, leading to UV Index readings that can soar to 9 at peak hours. Familiarizing yourself with this information helps protect you and your loved ones from potential skin damage, ensuring you enjoy the outdoors responsibly.
As the sun rises, the UV Index starts at a gentle 1 at 07:00, perfect for those early morning strolls. By 08:00, it nudges up to 2, signaling a gradual increase in sun intensity. The UV rays become more prominent by 09:00, reaching a 3, and then escalate significantly as the day progresses. At 10:00, the index spikes to 5, and by 11:00 it reaches 6, indicating a real need for sun protection. The peak occurs at 12:00, where the UV Index hits a striking 8, followed closely by a 9 at 13:00, marking the most intense sun exposure. As the afternoon rolls in, from 14:00 onwards, the UV levels start to wane, settling at 8 and gradually decreasing to 7 by 15:00. The evening approaches with a decrescendo; the index drops to 5 at 16:00, tailing off to 4 by 17:00, and finally winding down to 1 by 19:00. Throughout the day, awareness and protection make all the difference in enjoying the outdoors safely!
| 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 | 6 | high | 25 min |
| 12:00 | 8 | very high | 15 min |
| 13:00 | 9 | 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 | 4 | moderate | 30 min |
| 18:00 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
As the seasons change, so too does the UV Index, highlighting the need for awareness regarding sun exposure. January and December feature a low UV Index of 2, allowing for longer burn times of 45 minutes. In the spring, the UV Index begins to escalate, with April reaching a high of 7 (high exposure category) and a 25-minute burn time. The summer months, particularly May and June, present the greatest risk with a peak UV Index of 10 and a burn time of just 15 minutes. As we transition into late summer and fall, the UV Index decreases slightly, but September still holds a significant 7, indicating high risk. To ensure safety, residents and visitors should prioritize sun protection, especially from May through September, when UV radiation is at its highest. Appropriate measures include 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 |
| Saint John | 2 | 3 | 5 | 7 | 9 | 10 | 8 | 8 | 7 | 5 | 3 | 2 |
| Toronto UVI | 2 | 4 | 5 | 8 | 9 | 9 | 9 | 9 | 7 | 5 | 3 | 2 |