Last updated: June 2, 2025
Understanding the UV Index is crucial for residents and visitors of Izumo, Japan, where the climate is characterized by hot summers and mild winters. As the UV Index can peak at 11 during midday, being aware of the UV levels helps in preventing sunburn and maintaining overall skin health. With the region's typical exposure risks, especially during the summer months, vigilance is key to enjoying the beautiful outdoors while safeguarding against harmful radiation. Stay informed about the UV Index to ensure that your sun-soaked adventures in Izumo remain safe and enjoyable!
The UV Index begins its climb at 07:00 with a mild 2, gradually escalating to a peak of 11 at 12:00. As the sun reaches its zenith, so does the intensity of ultraviolet rays, making this the most critical time for sun safety. From 13:00, the index gradually descends, dropping to 6 by 15:00, then tapering off further to 4 at 16:00. As evening approaches, the UV levels decrease significantly, settling at 2 by 17:00, and then dwindling to a minimal 1 after 18:00. To sum up, it's crucial to take protective measures during the midday hours when the UV Index peaks, ensuring you're shielded from harmful rays.
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 2 | low | 45 min |
| 08:00 | 4 | moderate | 30 min |
| 09:00 | 6 | high | 25 min |
| 10:00 | 8 | very high | 15 min |
| 11:00 | 10 | very high | 15 min |
| 12:00 | 11 | extreme | 10 min |
| 13:00 | 10 | very high | 15 min |
| 14:00 | 9 | very high | 15 min |
| 15:00 | 6 | high | 25 min |
| 16:00 | 4 | moderate | 30 min |
| 17:00 | 2 | low | 45 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, the UV Index experiences notable fluctuations, with significant increases during the spring and summer months. March marks the beginning of high-risk UV exposure, peaking in July and August at a severe UV Index of 12, where the recommended burn time is just 10 minutes. Both April and May maintain an extreme category, urging outdoor enthusiasts to exercise caution. From September onward, UV levels gradually decline, but the risk remains high into early fall. Residents and visitors are advised to protect themselves, especially during the high-risk months of March to September, by applying sunscreen, wearing protective clothing, and seeking shade to minimize sun exposure. As the year progresses, understanding and adapting to these changes can help ensure safety and enjoyment in outdoor activities.
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 |
| Izumo | 4 | 5 | 8 | 11 | 11 | 11 | 12 | 12 | 10 | 7 | 5 | 3 |
| Osaka UVI | 4 | 6 | 8 | 11 | 11 | 11 | 12 | 11 | 10 | 7 | 5 | 3 |