San Juan, Puerto Rico UV Index in December
The average UV index in San Juan, Puerto Rico in December is about 9.2 (Very High), peaking near 11.7 at midday on clear days. Fair skin (Type II) can burn in roughly 10 minutes without sunscreen. SPF 50+ sunscreen, protective clothing, hat and sunglasses. Minimise midday sun exposure.
What is the UV index in San Juan, Puerto Rico in December?
Average UV
9.2
Very High
Midday Peak
11.7
Clear-sky estimate
Fair Skin Burn Time
10 min
Type II, no sunscreen
How long can you stay in the sun in San Juan, Puerto Rico in December?
| Skin type | Time to first burn | With SPF 30 |
|---|---|---|
| Type 1 | 7 min | up to 210 min |
| Type 2 | 10 min | up to 240 min |
| Type 3 | 16 min | up to 240 min |
| Type 4 | 26 min | up to 240 min |
| Type 5 | 39 min | up to 240 min |
| Type 6 | 59 min | up to 240 min |
Estimates based on San Juan, Puerto Rico's latitude and typical December sun angle. Cloud cover, altitude and reflection from water or sand can raise or lower the real UV. Check the live forecast before long days outside.
San Juan, Puerto Rico UV Index by Month
When is the UV index highest and lowest in San Juan, Puerto Rico?
Highest: May (about 11). Lowest: December (about 9.2).
| Month | Average UV | Midday peak | Level | Fair skin burn |
|---|---|---|---|---|
| January | 9.4 | 12 | Very High | 10 min |
| February | 10 | 12 | Very High | 9 min |
| March | 10.6 | 12 | Very High | 8 min |
| April | 10.9 | 12 | Very High | 8 min |
| May | 11 | 12 | Extreme | 8 min |
| June | 11 | 12 | Extreme | 8 min |
| July | 11 | 12 | Extreme | 8 min |
| August | 11 | 12 | Extreme | 8 min |
| September | 10.8 | 12 | Very High | 8 min |
| October | 10.2 | 12 | Very High | 9 min |
| November | 9.6 | 12 | Very High | 9 min |
| December | 9.2 | 11.7 | Very High | 10 min |
Common questions about UV in San Juan, Puerto Rico in December
Do you need sunscreen in San Juan, Puerto Rico in December?
Yes. A UV index of 9.2 is Very High, so use SPF 30+ on exposed skin between 10am and 4pm and reapply every two hours.
Can you tan in San Juan, Puerto Rico in December?
Yes, UV of 9.2 is strong enough to tan. Fair skin can burn in about 10 minutes, so build exposure slowly and use sunscreen.
What time of day is UV strongest in San Juan, Puerto Rico?
UV peaks around solar noon, roughly 11am to 2pm local time, when it can reach about 11.7 in December. Mornings and late afternoons are safest.
Is December a good month to visit San Juan, Puerto Rico for the sun?
December averages UV 9.2, compared with a yearly high of 11 in May and a low of 9.2 in December. Darker skin (Type VI) can burn in about 59 minutes at this level.