Last updated: June 2, 2025
In Montreal, United States, being aware of the UV Index is crucial for maintaining your skin health and preventing sunburn. The UV Index indicates the strength of ultraviolet radiation at a given time, and understanding these levels empowers residents to take necessary precautions, particularly during the peak hours of 11:00 AM to 3:00 PM, when the UV Index can soar to 10. With Montreal's humid continental climate (Dfb), sunny days can pose significant exposure risks even during cooler seasons. By staying informed about the UV Index, you can enjoy the outdoors safely while protecting your skin from harmful effects associated with excessive sun exposure.
As the sun rises, the UV Index starts its ascent, with a gentle 1 at 07:00. By 08:00, it begins to climb, reaching 2, signaling a reminder to take care. The real intensity kicks in at 10:00, where the index peaks at 6, escalating to a scorching 9 by noon. The hottest moment arrives at 13:00, showcasing a dramatic 10—a level that demands serious sun protection. Although the UV level begins to drop after this peak, it remains notable; at 14:00, it settles at 9, then declines gently, hitting 3 by 17:00. As daylight fades towards the evening, it tapers off to 2 at 18:00 and finally returns to a safe 1 by 19:00. It's a vivid reminder of the sun's power throughout the day!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 2 | low | 45 min |
| 09:00 | 4 | 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 | 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 |
Throughout the year, UV exposure levels fluctuate significantly, peaking during the spring and summer months. The high-risk months, notably from April to August, feature very high UV indices ranging from 8 to 10, with only 15 minutes of safe exposure before risking sunburn. March also begins to elevate with a moderate index of 5. As autumn arrives, a gradual decline occurs, with September’s index at 7, followed by lowering values in October, November, and December. Visitors and residents are advised to take precautionary measures during the high-risk months, such as applying sunscreen, wearing protective clothing, and seeking shade, especially during midday hours to minimize the risk of UV-related health issues. Remember, even on cloudy days, UV rays can penetrate the atmosphere, so staying vigilant is key!
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Montreal | 2 | 4 | 5 | 8 | 8 | 10 | 9 | 8 | 7 | 5 | 3 | 2 |
| Chicago UVI | 3 | 4 | 6 | 8 | 9 | 10 | 10 | 9 | 8 | 6 | 4 | 2 |
| Brooklyn UVI | 3 | 5 | 6 | 8 | 10 | 10 | 9 | 9 | 8 | 6 | 4 | 2 |
| New York City UVI | 3 | 5 | 6 | 8 | 10 | 10 | 9 | 9 | 8 | 6 | 4 | 2 |
| Los Angeles UVI | 4 | 6 | 8 | 9 | 10 | 11 | 11 | 10 | 10 | 7 | 5 | 4 |
| Houston UVI | 5 | 8 | 9 | 11 | 11 | 12 | 12 | 11 | 10 | 9 | 7 | 5 |