Last updated: June 2, 2025
In Ojika, Japan, understanding the UV Index is essential for protecting your skin and overall health, especially as the island enjoys a humid subtropical climate (Cfa) that can magnify sun exposure risks. With UV levels often peaking at a striking 11 during midday hours, staying informed about these fluctuations can help residents and visitors alike prevent sunburn and long-term skin damage. By recognizing the daily UV intensity, you can take proactive steps to enjoy the sunny days safely while preserving your skin’s health under the radiant sun.
The UV Index throughout the day showcases a remarkable rise, peaking impressively at 11 between noon and 1 PM. Starting with a modest 1 at 7 AM, the index escalates to around 3 by 8 AM and rapidly climbs, hitting 5 by 9 AM. The ascent continues as the sun reaches its zenith, soaring to 8 at 10 AM and breaching the 10 mark by 11 AM. As we reach peak sun hours, it stabilizes at 11 for both 12 PM and 1 PM, before gradually descending to 9 at 2 PM and tapering off to 7 by 3 PM. The latter part of the afternoon sees a gentle decline to 4 at 4 PM, finally returning to the morning's low of 1 by 6 PM, and maintaining this relaxed level through 7 PM. It's a vivid reminder of the sun's strength, urging outdoor enthusiasts to stay sun-smart during the intense midday hours!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 3 | moderate | 30 min |
| 09:00 | 5 | moderate | 30 min |
| 10:00 | 8 | very high | 15 min |
| 11:00 | 10 | very high | 15 min |
| 12:00 | 11 | extreme | 10 min |
| 13:00 | 11 | extreme | 10 min |
| 14:00 | 9 | very high | 15 min |
| 15:00 | 7 | 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, UV radiation levels dramatically fluctuate, impacting the risk of skin damage for both visitors and residents. The highest risk months occur from May to August, where the UV Index peaks at 11 to 12, indicating an extreme exposure category with a burn time of just 10 minutes. During these months, it is crucial to limit direct sun exposure and utilize protective measures such as sunscreen, hats, and clothing to safeguard skin health. March and April also present high levels of concern, categorized as very high with burn times of just 15 minutes. As seasons shift into fall and winter, the UV Index decreases, with December and January showing a moderate level, allowing for longer safe exposure times of 30 minutes. However, even during lower UV months, protective precautions are still advised. Stay informed and protect yourself year-round!
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 |
| Osaka UVI | 4 | 6 | 8 | 11 | 11 | 11 | 12 | 11 | 10 | 7 | 5 | 3 |
| Ojika | 4 | 6 | 8 | 10 | 11 | 11 | 12 | 12 | 10 | 7 | 6 | 4 |