San Juan Weather in January
January is one of the perfect months to visit San Juan, with daytime temperatures of 28°C (82°F) and lows of 22°C (72°F) at night. Some rainfall is typical for this time of year.
Rainfall in San Juan in January
Past climate data indicates that roughly 20 days will see rain, totalling around 55 mm (2.2 in) for the month. Rain is frequent but mostly light this month, with brief showers more common than heavy downpours.
Temperature in San Juan in January
January is a perfect month in San Juan, with 28°C (82°F) during the day and 22°C (72°F) at night. This kind of day-to-night contrast is typical for this time of year. Nights remain mild at 22°C (72°F), making evenings a pleasant time to be outdoors. This coolest month of the year still offers plenty of warmth and comfortable days.
Sunshine in San Juan in January
With approximately 238 hours of sunshine, the days are filled with clear skies. It makes it a perfect month for being outside.
Wind Speed in San Juan in January
January has wind speeds averaging 3 m/s (6 knots). You can expect comfortable light winds that steadily move flags and feel mild throughout the day. Since this is an average, daily conditions vary from gentle winds to more active breezes.
Average water temperature in January
The water temperature is 26°C (79°F), which most people find very comfortable. A good month for swimming and water sports.If you're a fan of comfortable temperatures and drier conditions, January is a great time to visit.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Puerto Rico, check out our San Juan's climate page.
San Juan Temperature in January
Min Temperature
22°C (72°F)
Max Temperature
28°C (82°F)
Water Temperature
26°C (79°F)
Chance of Rain
66%
Precipitation
55 mm (2.2 in)
Rainy days
20 days
Humidity
74%
Windspeed
3 m/s (6 knots)
Sunshine
238 hours
Percentage Sunshine
70%
Daily Historical Temperatures
51-year average (1976-2026)
Based on our historical records, temperatures in San Juan typically stay consistent throughout January, with daily highs averaging around 28°C (82°F). Nights are warm, with lows around 22°C (72°F).
Average temperatures in January
Daily Historical Precipitation
51-year average (1976-2026)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in January
Historical weather for San Juan in January
Browse day-by-day weather records for San Juan spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
San Juan historical weather extremes in January
The extremes listed below come from historical weather data collected in San Juan from 1976 through 2025.
- The warmest day in January was on January 23, 2018, with a maximum of 34°C (93°F).
- On January 28, 2006, San Juan saw its coldest January day with temperatures maxing out at 23°C (73°F).
- San Juan registered its coldest January night on January 20, 2000, with temperatures dropping to 17°C (63°F).
Best Places in Puerto Rico in January
Find out more about the weather in Puerto Rico and which places have the best travel conditions in this month. See all of Puerto Rico in January →
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What to Wear in San Juan in January
Warm temperatures in January make for comfortable sightseeing weather. Pack breathable fabrics like cotton shirts, knee-length shorts or skirts, and comfortable walking shoes. A thin long sleeve for indoor spaces is handy. Rain gear is recommended, you can expect wet weather on multiple days. The water temperature sits at about 26°C (79°F), making it perfect for swimming and water activities. Don't forget to pack your favorite swimwear and perhaps some snorkel gear. Don't forget sun protection, sunglasses, sunscreen, and a hat. These are all good ideas with this much sunshine.What To Do in San Juan in January
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Puerto Rico, check out our San Juan's climate page.
Temperature Rainfall Sunshine Humidity Wind Speed Water Temp
See the full San Juan climate overview or explore weather in Puerto Rico.
