Last updated: July 2, 2025
Understanding the UV Index is crucial for residents and visitors of San Diego, where sunny weather often tempts outdoor activities. Being aware of UV levels can significantly reduce the risk of sunburn and long-term skin damage, making it essential for maintaining overall skin health. With San Diego's temperate coastal climate, UV exposure can be intense, particularly during midday hours when the index peaks—reaching as high as 12 around noon. By monitoring the UV Index, you can better protect yourself while enjoying all that this beautiful city has to offer.
Throughout the day, the UV Index displays a dynamic rise and fall in intensity, starting with a gentle 1 at 07:00 and maintaining low levels of 1 at 08:00. As the sun climbs higher, the index sharply escalates, reaching 2 by 09:00 and surging to 5 at 10:00. The peak UV Index occurs during midday, hitting a striking 12 at both 13:00 and 14:00, signifying the need for effective sun protection. Following this zenith, the UV levels gracefully decline, tapering off to 10 by 15:00, then 8 at 16:00, and dwindling back down to 2 by 18:00. The day concludes under fading sunlight, with the UV Index returning to a safe 1 by 19:00. Always take care to guard against those midday rays when the sun is at its most powerful!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 1 | low | 45 min |
| 09:00 | 2 | low | 45 min |
| 10:00 | 5 | moderate | 30 min |
| 11:00 | 7 | high | 25 min |
| 12:00 | 10 | very high | 15 min |
| 13:00 | 12 | extreme | 10 min |
| 14:00 | 12 | extreme | 10 min |
| 15:00 | 10 | very high | 15 min |
| 16:00 | 8 | very high | 15 min |
| 17:00 | 5 | moderate | 30 min |
| 18:00 | 2 | low | 45 min |
| 19:00 | 1 | low | 45 min |
Throughout the year, UV Index levels fluctuate significantly, with the highest readings occurring in the summer months. From May to August, the UV Index reaches an extreme level of 12, posing the greatest risk for sunburn, with a minimal safe exposure time of just 10 minutes. April and September also see high values, with an index of 11. Visitors and residents are advised to take extra precautions during these high-risk months, such as applying sunscreen, wearing protective clothing, and seeking shade during peak sun hours. Conversely, in the winter months, from December to February, UV levels are lower, ranging from moderate to very high, but individuals should remain vigilant, especially in February and March when the index peaks at 8 and 10. Overall, awareness and protection against UV radiation are essential year-round, particularly during the hotter months.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 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 |
| San Diego | 6 | 8 | 10 | 11 | 11 | 12 | 12 | 12 | 11 | 9 | 7 | 5 |