The highest day temperature in January 2025 was 89°F. The lowest night temperature was 73°F. The average values for day and night temperatures during January were 84.2°F и 79.3°F respectivly.

The average sea surface temperature in January 2025 for San Juan was 85.0°F. The maximum and minimum values were 84.2°F and 86.0°F respectively.

Most of the days in January are cloudy but you can also expect sunny or gloomy days.

Precipitation total in January for San Juan is 42.5 in. It makes january the most rainy month of the year.

The average wind speed in January is 11.4 mph.

We are using day length and cloud cover information for each day of the month to calculate averages for this chart. Average sunny hours for San Juan in January is 6.1 hours.