Last updated: June 2, 2025
Being aware of the UV Index in Kariwa, Japan is essential for safeguarding your skin and overall health. Understanding UV levels plays a crucial role in preventing sunburn and long-term skin damage, especially as the sun reaches its peak intensity in this region. With a humid subtropical climate, Kariwa experiences significant UV exposure, particularly during midday when the index can soar to levels of 11. By staying informed about daily UV fluctuations, residents and visitors can take proactive measures to enjoy the sun safely while protecting their skin from harmful rays.
As the sun rises, the UV Index begins its ascent, starting at a moderate level of 2 at 07:00. By 08:00, it climbs to 4, signaling an increase in sun exposure. The index peaks at 11:00, reaching a high of 10, marking the day's most intense UV radiation. 12:00 sees an even sharper rise to 11, a reminder to seek shelter or don sunscreen if heading outdoors. After this zenith, the UV Index gradually descends, with 10 at 13:00 and steadily decreasing through the afternoon—8 at 14:00, 5 at 15:00, and finally dipping to 2 at 17:00. As daylight fades, the index drops to 1 by 18:00 and becomes negligible at 0 by 19:00, signaling the end of the day's UV intensity. Always remember to take precautions during those peak hours!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 2 | low | 45 min |
| 08:00 | 4 | moderate | 30 min |
| 09:00 | 7 | high | 25 min |
| 10:00 | 9 | 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 | 8 | very high | 15 min |
| 15:00 | 5 | moderate | 30 min |
| 16:00 | 3 | moderate | 30 min |
| 17:00 | 2 | low | 45 min |
| 18:00 | 1 | low | 45 min |
| 19:00 | 0 | low | 45 min |
As the seasons change, so does the UV Index, impacting both visitors and residents. From January to February, the UV Index remains at a moderate level (3-4), allowing for 30 minutes of sun exposure without significant risk. However, as spring approaches in March, the index climbs to high (7), reducing safe exposure to 25 minutes. The peak UV Index occurs during summer months, notably in July and August, where it reaches an extreme level (11) with a mere 10 minutes of safe exposure. September sees a decline to very high (9), while October returns to high (6) conditions, each allowing for a bit more time in the sun—25 minutes and 15 minutes respectively. From November to December, the UV risks lower again to moderate (3-4), allowing for 30 minutes. Visitors and residents should be especially cautious from March through September, particularly during peak summer months, by applying sunscreen, wearing protective clothing, and limiting sun exposure to mitigate the risk of UV-related health issues.
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 |
| Kariwa | 3 | 4 | 7 | 8 | 10 | 10 | 11 | 11 | 9 | 6 | 4 | 3 |
| 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 |