San Blas, Mexico UV Index Today – Burn Times & Sun Safety
Updated: Monday, May 18, 2026
The UV index in San Blas, Mexico averages 7 (High) with peaks reaching 10. At moderate-to-high UV levels, sun protection including SPF 30+ sunscreen, hat, and sunglasses is recommended, especially between 10 AM and 4 PM.
Current UV Conditions in San Blas, Mexico
The ultraviolet radiation in San Blas is currently at High levels. Protection required. Reduce sun exposure between 10am-4pm, apply SPF 30+ every 2 hours.
- Average UV Index: 7 (High)
- Peak UV Index: 10
- UV Risk Category: High — protection recommended
- Peak UV Hours: 10:00 AM – 4:00 PM local time
- Region: North America
Burn Time by Skin Type in San Blas
Estimated time to first sunburn at UV 7 in San Blas for each Fitzpatrick skin type, with protection times using SPF 30 and SPF 50 sunscreen. Estimates assume continuous direct sun exposure at solar noon on a clear day.
| Skin Type | Description | Burn Time (No SPF) | With SPF 30 | With SPF 50 |
|---|---|---|---|---|
| Type I (Very Fair) | Pale white skin, always burns, never tans | 14 min | 42 min | ~1h 10m |
| Type II (Fair) | White skin, burns easily, tans minimally | 21 min | ~1h 3m | ~1h 45m |
| Type III (Medium) | Cream/light brown, sometimes burns, tans uniformly | 29 min | ~1h 27m | 2h 25m |
| Type IV (Olive) | Moderate brown, rarely burns, tans easily | 43 min | 2h 9m | 3h 35m |
| Type V (Brown) | Dark brown skin, very rarely burns | ~1h 4m | 3h 12m | 5h 20m |
| Type VI (Dark) | Deeply pigmented dark brown to black | ~1h 26m | 4h 18m | 7h 10m |
Source: Estimates derived from the Fitzpatrick classification system and WHO UV exposure guidelines. Individual results vary based on skin condition, medication, altitude, and surface reflection.
SPF and Sunscreen Advice for San Blas
With high UV levels in San Blas, SPF 30+ sunscreen provides adequate protection for most activities. Apply generously 15 minutes before going outside and reapply every 2 hours. For water-based activities, choose a waterproof formula and reapply after swimming. SPF 50 is recommended for fair-skinned visitors (Fitzpatrick Type I-II) and anyone spending extended periods outdoors.
Why UV Is Intense in San Blas
San Blas experiences moderate to high UV levels influenced by latitude, season, and local geography. UV intensity peaks during solar noon and summer months, and is amplified by altitude, water reflection, and thin cloud cover.
Key factors affecting UV intensity in San Blas:
- Latitude: San Blas's geographic position determines the angle of incoming solar radiation, directly impacting UV strength
- Altitude: UV intensity increases approximately 10-12% for every 1,000 metres of elevation gain
- Season: UV peaks during local summer months when the sun reaches its highest point in the sky
- Ozone layer: Regional ozone thickness varies, affecting how much UV-B radiation reaches the surface
- Surface reflection: Water reflects up to 100% of UV, sand 15-25%, concrete 10%, and snow 80%
- Cloud cover: Up to 80% of UV rays penetrate thin cloud cover — overcast days are not UV-safe
Activity Guide for San Blas at UV 7
How current UV levels in San Blas affect popular outdoor activities and what precautions you should take:
- Beach and swimming: Apply SPF 30+ waterproof sunscreen before heading out. Reapply every 2 hours
- Sightseeing and walking: Wear a hat and sunglasses. Seek shade during midday breaks
- Running and cycling: Best before 10 AM or after 4 PM. Apply SPF 30 to exposed skin
- Hiking: Carry sunscreen and wear a hat. Take regular shade breaks every 45 minutes
- Children's activities: Apply SPF 30+ and limit direct midday sun exposure
Best Times for Outdoor Activities in San Blas
- Early Morning (6:00–9:00 AM): Lowest UV levels — ideal for running, cycling, and exercise
- Mid-Morning (9:00–10:00 AM): UV rising — apply sunscreen before heading out
- Midday (10:00 AM–4:00 PM): Peak UV exposure — limit time outdoors, seek shade, and wear full protection
- Late Afternoon (4:00–6:00 PM): Decreasing UV — good for beach time, sightseeing, and outdoor dining
- Evening (after 6:00 PM): Negligible UV — safe for all outdoor activities
Sun Protection Checklist for San Blas
- Apply broad-spectrum SPF 30+ sunscreen 15-30 minutes before sun exposure
- Reapply sunscreen every 2 hours, or immediately after swimming or sweating
- Seek shade during peak UV hours (10:00 AM – 4:00 PM)
- Wear a wide-brimmed hat (7cm+ brim) and UV-blocking sunglasses (Category 3+)
- Choose tightly woven, dark-coloured clothing or UPF-rated garments for maximum protection
- Be extra cautious near water, sand, and concrete where UV reflection increases effective exposure by 15-100%
- Check the UV forecast hourly — UV levels change significantly throughout the day
Frequently Asked Questions About UV in San Blas
What is the UV index in San Blas, Mexico today?
The UV index in San Blas typically ranges from 5 to 10 depending on time of day, season, and cloud cover. Peak UV occurs between 10:00 AM and 4:00 PM local time. Use Daily UV Tracker for real-time hourly UV data.
How long can I stay in the sun in San Blas without burning?
At UV 7 in San Blas, fair-skinned individuals (Fitzpatrick Type I) may burn in as little as 14 minutes without protection. Medium skin types (Type III) can typically tolerate 29 minutes. Always apply sunscreen regardless of skin type — UV damage accumulates even without visible sunburn.
What SPF should I use in San Blas?
SPF 30+ is recommended for most activities in San Blas. Apply 15 minutes before sun exposure and reapply every 2 hours. Use SPF 50 for extended outdoor time or water activities.
When is the sun strongest in San Blas?
UV radiation peaks in San Blas between 10:00 AM and 4:00 PM local time, with maximum intensity around solar noon (approximately 12:30-1:30 PM). Schedule intense outdoor activities for early morning or late afternoon when UV is lowest.
Is San Blas safe for people with fair skin?
San Blas is safe for fair-skinned visitors with proper sun protection. At UV 7, Type I skin can burn in under 14 minutes without sunscreen. Wear SPF 30+, a wide-brimmed hat, UV-blocking sunglasses, and seek shade during midday hours. Lightweight long-sleeved shirts with UPF ratings provide excellent protection.
Does cloud cover reduce the UV in San Blas?
Clouds can reduce UV intensity, but thin or scattered clouds block only 20-30% of ultraviolet radiation. Up to 80% of UV rays penetrate light cloud cover in San Blas, meaning you can still burn on overcast days. Always apply sunscreen regardless of cloud conditions, especially during peak UV hours.