Last updated: July 2, 2025
In Numazu, Japan, staying informed about the UV Index is crucial for protecting your skin and overall health. Understanding UV levels not only helps prevent painful sunburns but also plays a vital role in reducing the risk of long-term skin damage. With a Cfa climate, Numazu enjoys a temperate environment, but UV exposure can spike during the bright summer months, especially around midday when the index reaches a peak of 12. By keeping an eye on the UV Index and taking appropriate precautions, residents and visitors can safely enjoy the beautiful outdoors while safeguarding their skin health.
The UV index today begins with a gentle rise, starting at a modest 2 at 7:00 AM. As the sun climbs higher, it reaches 5 by 8:00 AM, quickly escalating to a peak 12 by both 11:00 AM and 12:00 PM—indicating the highest intensity of UV radiation. From that point, the index starts to decline, dropping to 11 at 1:00 PM, and then gently easing down to 8 by 2:00 PM. The afternoon watches the UV levels further retreat to 6 at 3:00 PM, finally tapering off to a cool 1 by 5:00 PM, settling to 0 by 7:00 PM. It's a day where early sun seekers must take care, especially during the midday hours.
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 2 | low | 45 min |
| 08:00 | 5 | moderate | 30 min |
| 09:00 | 8 | very high | 15 min |
| 10:00 | 10 | very high | 15 min |
| 11:00 | 12 | extreme | 10 min |
| 12:00 | 12 | extreme | 10 min |
| 13:00 | 11 | extreme | 10 min |
| 14:00 | 8 | very high | 15 min |
| 15:00 | 6 | high | 25 min |
| 16:00 | 3 | moderate | 30 min |
| 17:00 | 1 | low | 45 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 0 | low | 45 min |
Throughout the year, the UV Index demonstrates notable seasonal changes, with the most intense exposure occurring from April to August. During these months, the UV Index reaches extreme levels (10-12), significantly reducing the burn time to just 10 minutes. March and September also pose risks with very high levels (8-10), allowing for a burn time of only 15 minutes. Consequently, February and October present high levels (6-7), where protective measures are still advised with adjusted burn times of 25 minutes. Residents and visitors should exercise caution and protect their skin, especially during the high-risk months of April through August, by using sunscreen, wearing protective clothing, and limiting sun exposure during peak hours.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sapporo UVI | 2 | 3 | 6 | 7 | 9 | 9 | 9 | 10 | 8 | 5 | 3 | 2 |
| Yokohama UVI | 3 | 5 | 8 | 9 | 11 | 11 | 11 | 11 | 10 | 7 | 5 | 4 |
| Tokyo UVI | 3 | 5 | 8 | 9 | 11 | 11 | 11 | 11 | 10 | 7 | 5 | 4 |
| Nagoya UVI | 4 | 6 | 8 | 10 | 11 | 11 | 11 | 11 | 10 | 7 | 5 | 3 |
| Numazu | 4 | 6 | 8 | 10 | 11 | 11 | 12 | 11 | 10 | 7 | 5 | 4 |
| Osaka UVI | 4 | 6 | 8 | 11 | 11 | 11 | 12 | 11 | 10 | 7 | 5 | 3 |