The month in detail
What to expect in December
December falls in the wet season in San Juan. Showers are often brief but intense. With 57.0% of rainy days, always have indoor alternatives planned. A good balance between weather and crowds, even if March (8.1/10) remains theoretically better.
December ranks 4 out of 12 months in San Juan. Compared to November: 10 pts fewer rainy days.
This month's conditions
What it's like in December
UV index
6 · high
sunscreen and hat advised
Feels like
very humid
21°
Sea
29°C
warm, ideal
Daylight
10.9h of daylight
Air quality
good
AQI 27
Compare
Is December the right month?
The best month in San Juan is March (8.1/10), 0.3 pt higher than December.
Context
Our verdict
San Juan, capital of Puerto Rico on the north-east coast: 320,000 inhabitants intra-muros, 2.3 million in urban area.
Book
Plan your trip
Hotels at their lowest outside peak season, highest on comfortable months. Shoulder seasons offer a good price/climate compromise.
Stay
Hotels & rentals · San Juan
Expedia →
Activities
Tours, tickets, experiences
See ↓
Flights
Multi-airline comparator
Kiwi →
🎟️ Activities & tours · San Juan
GetYourGuide selection · free cancellation
Practical info
What you need to know before you go
Three angles: the country (language, currency, safety, budget), the year-round climate, and the specifics of a tropical stay.
Country · Puerto Rico
🗣️LanguageSpanish
💶CurrencyUS Dollar ($)
🚗DrivingRight-hand
🛡️Safety ⓘVery safe · 1/5
💰Cost of living ⓘExpensive · 4/5
🌡️ Climate
🌍Climate typeTropical
📈Climate trend ⓘStable
🔥Hottest monthJune · 31°C
❄️Coolest monthJanuary · 28°C
🌧️Rainiest month ⓘSeptember · 74%
🏝️ Tropical stay
🌞Dry season ⓘMay → Sep
🌧️Wet season ⓘDec → Mar
🌀Cyclones ⓘSeason Nov-Apr
Explore
Other destinations in December
If December doesn't convince you for this destination, compare with others.
Similar climate
Puerto RicoPuerto Rico
BasseterreSaint Kitts and Nevis
AntiguaAntigua and Barbuda
GuadeloupeGuadeloupe
MartiniqueMartinique
Location
Where is San Juan ?
Global position + regional geographic context.
🌍 World
🔍 Geographic context
Puerto RicoTropical climate with a 8.1 → 4.7 gap between best and worst month. 10 years of ERA5 data to choose by project.
18.47°N · 66.11°W
Questions
Frequently asked questions
What is the best time to visit San Juan?
January is the best month with 28.0°C highs, 22.0°C lows, 7.7h of sunshine and 47.0% rainy days. The months of January & March offer comparable conditions.
How many hours of sunshine does San Juan get in January?
San Juan averages 7.7 sunshine hours per day in January. It is the sunniest month with a climate score of 7.5/10.
What is the rainiest month in San Juan?
September is the most unfavourable month with September has the lowest climate score of the year and the lowest climate score of the year.
What are the temperatures at night in San Juan in January?
In January, overnight lows reach 22.0°C, while afternoon highs average 28.0°C.
Is San Juan good in winter?
In winter (December-February), San Juan scores 7.4/10 on average — Decent period conditions for cultural visits.. The best month overall remains January with a score of 7.5/10.
When should you avoid San Juan?
September is the most difficult month to visit San Juan, with September has the lowest climate score of the year. Climate conditions are at their lowest of the year during this period.
Can you swim in San Juan in December?
In December, the sea averages 29°C in San Juan: warm, ideal. Ideal conditions for swimming and snorkeling.
Do you need sun protection in San Juan in December?
The average UV index reaches 6 in December in San Juan (high), with about 10.9h of daylight. Sunscreen and hat advised.