Last updated: May 3, 2025
Understanding the UV Index is crucial for anyone living in or visiting Costa Rica and Peru, where the sun can be particularly intense. As you enjoy the beautiful beaches and lush landscapes, being aware of the UV levels helps protect your skin from harmful rays, preventing sunburn and long-term skin damage. The tropical climate in Costa Rica, characterized by abundant sunshine and varying UV exposure throughout the day, means that from late morning to early afternoon, the UV Index can soar to extremely high levels (reaching 14). By staying informed about the UV Index, you can enjoy the outdoors safely while safeguarding your skin health.
As the sun rises at 07:00, the UV Index begins at a low 1, making early hours safe for outdoor activities. However, by 08:00, it ramps up to 3, signaling a gradual increase in sun intensity. The UV levels peak dramatically at 12:00, reaching a scorching 14—the perfect time to seek shade! Post-noon, the index starts to decline, with 13:00 still significant at 12, but easing to 9 by 14:00. As the afternoon fades, the UV Index drops to 5 by 15:00, and continues its descent to a mere 1 by 17:00, before vanishing completely after 18:00. This day highlights the importance of sun safety, particularly during the peak hours when UV radiation is most intense!
| Time | UVI | Category | Time to Burn |
|---|---|---|---|
| 07:00 | 1 | low | 45 min |
| 08:00 | 3 | moderate | 30 min |
| 09:00 | 6 | high | 25 min |
| 10:00 | 9 | very high | 15 min |
| 11:00 | 13 | extreme | 10 min |
| 12:00 | 14 | extreme | 10 min |
| 13:00 | 12 | extreme | 10 min |
| 14:00 | 9 | very high | 15 min |
| 15:00 | 5 | moderate | 30 min |
| 16:00 | 2 | low | 45 min |
| 17:00 | 1 | low | 45 min |
| 18:00 | 0 | low | 45 min |
| 19:00 | 0 | low | 45 min |
Throughout the year, the UV Index remains extremely high, particularly from January to April, where it peaks at 16. These months are critical for residents and visitors to take precautionary measures, as the burn time is only 10 minutes during this period. Although the index slightly declines during the summer months, it still remains significantly high, with values of 11 to 12 from June to August. As the year progresses into the fall, the index again reaches up to 15 in October, before tapering off slightly in November and December. It is advisable for everyone to wear sunscreen, protective clothing, and seek shade during peak sun hours, especially during the high-risk months of January through April. Staying informed and vigilant about UV exposure can help minimize the risk of sunburn and long-term skin damage.
UV Risk Categories
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Callao UVI | 14 | 14 | 14 | 12 | 10 | 9 | 10 | 11 | 12 | 13 | 14 | 13 |
| Lima UVI | 14 | 14 | 14 | 12 | 10 | 9 | 10 | 11 | 12 | 13 | 14 | 13 |
| Trujillo UVI | 15 | 15 | 15 | 14 | 12 | 11 | 11 | 11 | 13 | 14 | 14 | 14 |
| Chiclayo UVI | 14 | 15 | 15 | 14 | 13 | 11 | 11 | 12 | 15 | 14 | 14 | 13 |
| Costa Rica | 15 | 16 | 16 | 16 | 14 | 11 | 11 | 12 | 14 | 15 | 14 | 14 |
| Arequipa UVI | 18 | 17 | 17 | 15 | 12 | 10 | 11 | 13 | 15 | 17 | 18 | 17 |