Last updated: August 1, 2025
Understanding the UV Index is crucial for residents of Portage, United States, where the climate can bring about varying levels of sun exposure throughout the year. Being aware of the UV levels not only helps in preventing painful sunburns but also plays a vital role in maintaining long-term skin health. With Portage experiencing a climate classified as Dfb, the risk of high UV radiation is particularly prevalent during midday hours, peaking at an index of 10 around 1 PM. By staying informed about the UV Index, you can enjoy the sunshine safely while minimizing potential harm.
As the day unfolds, the UV Index experiences a dramatic rise, peaking at an intense 10 around 1 PM, signaling the highest level of harmful UV radiation. Early morning hours start gently, with a maximum of 1 at 7 AM, gradually increasing to a moderate 4 by 9 AM. The ascent continues steadily, reaching a notable 8 between 11 AM and 12 PM before soaring to its zenith. After this peak, the index begins to wane, declining to 5 by 4 PM and dropping further to a safe 1 by 7 PM. It’s vital to stay protected during the peak hours of 11 AM to 3 PM to enjoy the sunshine without compromising skin health.
| 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 UV levels, highlighting periods of higher risk for sun exposure. From January to March, the UV Index remains low to moderate, with February seeing an increase. April to August marks the peak high-risk months, featuring very high UV levels, particularly in June and July, where the burn time drops to a remarkable 15 minutes. September transitions into a high UV category, while October to December see a gradual decline, returning to low risk by year's end. To protect yourself, especially during the high UV months of April through August, it is crucial to wear sunscreen, protective clothing, and seek shade to minimize exposure. Be particularly vigilant during the summer months when burn time is significantly reduced.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Portage | 2 | 4 | 5 | 8 | 9 | 10 | 10 | 9 | 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 |