Last updated: June 2, 2025
Understanding the UV Index is crucial for residents of River Forest, United States, where the climate falls under the humid continental zone (Dfa) and presents unique sun exposure risks. As the sun's rays become more intense throughout the day, knowing the UV levels can help protect against sunburn and promote long-term skin health. With peak UV levels reaching a significant 10 around midday, it's essential to stay informed and take appropriate precautions to enjoy the sunny days while minimizing the risk of harmful skin effects.
The hourly UV Index data reveals a dynamic shift in sun intensity throughout the day, starting from a gentle 1 at 07:00, ideal for morning strolls. As the sun rises higher, the index escalates, peaking at a potent 10 between 12:00 and 13:00. This mid-day surge emphasizes the need for sunscreen and protective gear, as the risk of harm from UV rays increases significantly. By 15:00, the index begins to decline, settling at 7 before tapering off further to a mere 1 by 19:00, signaling a safe reprieve for evening outdoor activities. Stay aware 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 | 4 | moderate | 30 min |
10:00 | 6 | high | 25 min |
11:00 | 8 | very high | 15 min |
12:00 | 10 | 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 varies significantly, with notable peaks between March and October. The high-risk months are April to August, where the UV Index consistently reaches very high levels of 8 to 10 and the burn time reduces to just 15 minutes. In contrast, the low-risk months of November and December see UV Index values fall to 3 and 2, respectively, allowing for safe exposure times of up to 30 and 45 minutes. Residents and visitors are advised to take extra precautions during the high-risk months by seeking shade, wearing protective clothing, and applying sunscreen regularly to mitigate the increased risk of sunburn and skin damage.
UV Risk Categories
Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
---|---|---|---|---|---|---|---|---|---|---|---|---|
River Forest | 3 | 4 | 6 | 8 | 9 | 10 | 10 | 9 | 8 | 6 | 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 |