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January Weather in San Juan, Peru

Last updated: August 27, 2025

In January, the average temperature in San Juan, Peru hovers around 12°C (54°F). Expect minimums of 6°C (42°F) and maximums reaching up to 20°C (69°F). This month is also characterized by significant precipitation, with 304 mm (12.0 in) spread over 24 days, resulting in an average humidity of 83%. Prepare for a moist climate as you navigate this vibrant destination!

January Temperature in San Juan

In January in San Juan, the average temperature is 12°C (54°F). The maximum can reach 20°C (69°F), while the minimum can be as low as 6°C (42°F). This mild climate makes San Juan an ideal destination for outdoor activities and exploring.

January Weather in San Juan: Daily Temperature Highs, Lows, and Averages

The chart illustrates January temperature patterns in San Juan, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In San Juan, January typically has an average temperature of 12°C (54°F), with highs reaching up to 20°C (69°F) and lows dropping to around 6°C (42°F).
JanFebMarAprMayJunJulAugSepOctNovDec545453545454545454545454
Data source: Temperature data for San Juan generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

January Precipitation in San Juan

In San Juan in January, the precipitation amount is 304 mm (12.0 in) spread over a total of 24 days.

January Precipitation Trends in San Juan

The chart displays monthly precipitation patterns in San Juan, with values for each month alongside January’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how January’s conditions compare to those of other months. In San Juan, January typically receives around 304 mm (12.0 inches) of precipitation spread over approximately 24 days.
JanFebMarAprMayJunJulAugSepOctNovDec304392599349189704348154299290413
Data source: Precipitation data for January generated using information from the Copernicus Climate Change Service.
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January Humidity in San Juan

In San Juan in January humidity is 83%. With an average temperature of 12°C (54°F), this humidity feels like a heavy blanket wrapping around you, making outdoor exploration feel sticky and uncomfortable, which can dampen the excitement of traveling.

January Average Humidity in San Juan

This chart illustrates the average monthly humidity levels in San Juan, with January’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In January, average humidity in San Juan is approximately 83%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec83%81%88%85%78%62%44%38%42%58%69%82%
Data source: Humidity data for January generated using information from the Copernicus Climate Change Service.

January UV Index in San Juan

In San Juan in January, the maximum UV index reaches an alarming 17, which falls under the extreme Exposure Category. With a time to burn of just 10 minutes, it's crucial to stay protected. For more details on the hourly UV index in San Juan, you can check Hourly UV Index in San Juan.

Maximum UV Index Levels in San Juan for January

The chart shows the monthly maximum UV Index (UVI) for San Juan in January, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In January, the maximum UV index in San Juan typically reaches 17, which falls under the extreme exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec171819181513141417181616
Data source: San Juan January UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

How January Weather in San Juan Compares to Other Months

Weather in San Juan varies notably across the year, with each month offering distinct climate conditions. This page compares January’s weather to other months in San Juan, focusing on differences in temperature, rainfall, humidity, and UV levels.

This table compares monthly weather conditions in San Juan, showing how January’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
 TemperaturePrecipitationHumidityUV
January Weather12°C (54°F)304 mm (12.0 inches)83%extreme
February Weather12°C (54°F)392 mm (15.4 inches)81%extreme
March Weather12°C (53°F)599 mm (23.6 inches)88%extreme
April Weather12°C (54°F)348 mm (13.7 inches)85%extreme
May Weather12°C (54°F)188 mm (7.4 inches)78%extreme
June Weather12°C (54°F)70 mm (2.8 inches)62%extreme
July Weather12°C (54°F)43 mm (1.7 inches)44%extreme
August Weather12°C (55°F)47 mm (1.9 inches)38%extreme
September Weather12°C (54°F)154 mm (6.1 inches)42%extreme
October Weather12°C (54°F)299 mm (11.8 inches)58%extreme
November Weather12°C (54°F)290 mm (11.4 inches)69%extreme
December Weather12°C (54°F)413 mm (16.2 inches)82%extreme

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