Last updated: May 3, 2025
Understanding the UV Index is essential for residents of Markham, Canada, where the climate, classified as Dfb, brings a mix of sunny days and seasonal variations. Being aware of UV levels not only helps you enjoy the outdoors safely but is crucial for preventing sunburn and protecting your skin health. With UV Index readings potentially peaking at 9 during midday, it’s important to know when to seek shade and apply sunscreen to mitigate your risks. As you navigate Markham’s vibrant summers, staying informed about UV exposure can make all the difference in safeguarding your well-being under the sun.
As the sun rises, the UV Index begins its gradual ascent. At 7:00 AM, it starts at a modest 1, indicating minimal risk. By 8:00 AM, it rises to 2, still manageable for early risers. The intensity picks up at 9:00 AM with a 3, signaling the need for a little sunscreen. The peak arrives between 11:00 AM and 1:00 PM, where it soars to a striking 9 at 1:00 PM, which suggests strong sun protection is essential. Following this, the index slips down, recorded at 8 at 2:00 PM and 7 at 3:00 PM, offering a brief reprieve. As the afternoon fades into evening, the UV Index drops steadily, landing back at 1 by 7:00 PM. Stay informed and protect your skin during those peak hours!
| 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 | 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 |
As the seasons change, so do the UV index levels, reflecting varying risks of sun exposure throughout the year. Late spring and summer present the highest UV indices, peaking at 9 from May to July, categorized as very high, with a burn time of just 15 minutes. This indicates that April through August are the critical months to be vigilant about sun protection, especially for those engaging in outdoor activities. Conversely, the UV index is at its lowest in January and December, where it drops to 2 with a low exposure category and a burn time of 45 minutes. Visitors and residents should prioritize sun safety during the high-risk months—consider wearing protective clothing, applying sunscreen regularly, and seeking shade during peak sunlight 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 |
| Markham | 2 | 4 | 5 | 8 | 9 | 9 | 9 | 8 | 7 | 5 | 3 | 2 |
| Toronto UVI | 2 | 4 | 5 | 8 | 9 | 9 | 9 | 9 | 7 | 5 | 3 | 2 |