Last updated: June 2, 2025
In Cornwall, Canada, being aware of the UV Index is essential for safeguarding your skin and overall health. Understanding UV levels helps you take proactive steps to prevent sunburn and reduce the risk of skin damage over time. With Cornwall’s Dfb climate, the sun can reach significant intensity during summer months, peaking at a UV Index of 10 around midday. This highlights the importance of monitoring UV exposure to enjoy the outdoors safely while protecting your skin from harmful rays.
As the sun rises, the UV Index begins its ascent, peaking at an invigorating 10 by 1:00 PM. Early morning, from 7:00 AM to 8:00 AM, sees a mild 1 to 2, making it a perfect time for a leisurely stroll. By 9:00 AM, the UV Index reaches 3, signaling a need for some sun protection. The real intensity kicks in around 11:00 AM, hitting 8, and just after noon, it soars to its daily maximum of 9. The afternoon hours see a slight decline, with values tapering from 9 at 2:00 PM to 6 by 4:00 PM. As daylight wanes, the UV Index gently drops to 1 by 7:00 PM, wrapping up a day of vibrant sunlight but reminding us to stay vigilant during those peak hours. Remember to reapply sunscreen and seek shade to keep safe while enjoying those sunny moments!
| 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 | 6 | high | 25 min |
| 11:00 | 8 | very high | 15 min |
| 12:00 | 9 | very high | 15 min |
| 13:00 | 10 | 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, the UV Index shows significant seasonal changes, indicating varying levels of sun exposure risk. The highest risk months are from April to August, where the UV Index reaches 7 to 10, classified as high to very high, with burn times diminishing to just 15 minutes during this peak period. In contrast, the winter months of January and December exhibit much lower UV levels, categorized as low, allowing for 45 minutes before burning occurs. It is crucial for visitors and residents to be especially vigilant during the high-risk months. Sunscreen, protective clothing, and avoiding peak sun hours are strongly advised to minimize the risk of skin damage.
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 |
| Cornwall | 2 | 3 | 5 | 7 | 8 | 10 | 8 | 8 | 7 | 5 | 3 | 2 |
| 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 UVI | 2 | 4 | 5 | 8 | 9 | 9 | 9 | 9 | 7 | 5 | 3 | 2 |