April Weather in San Juan, Costa Rica

Last updated: August 23, 2025

In April, the average temperature in San Juan, Costa Rica hovers around 21°C (70°F). Expect a minimum of 15°C (58°F) and a maximum soaring to 29°C (85°F). During this time, precipitation averages 79 mm (3.1 in) spread across 16 days, while the average humidity sits at a comfortable 67%. Embrace the season with its mix of warmth and occasional showers!

April Temperature in San Juan

In April in San Juan, the average temperature is 21°C (70°F). Maximums can reach up to 29°C (85°F), while minimums can dip as low as 15°C (58°F). This pleasant climate makes it an ideal time for outdoor activities and exploration.

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

The chart illustrates April 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, April typically has an average temperature of 21°C (70°F), with highs reaching up to 29°C (85°F) and lows dropping to around 15°C (58°F).
JanFebMarAprMayJunJulAugSepOctNovDec686969706969696968686868
Data source: Temperature data for San Juan generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

April Precipitation in San Juan

In San Juan in April, the precipitation amount is 79 mm (3.1 in) over a period of 16 days.

April Precipitation Trends in San Juan

The chart displays monthly precipitation patterns in San Juan, with values for each month alongside April’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how April’s conditions compare to those of other months. In San Juan, April typically receives around 79 mm (3.1 inches) of precipitation spread over approximately 16 days.
JanFebMarAprMayJunJulAugSepOctNovDec3213157939135123333143657020963
Data source: Precipitation data for April generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

April Humidity in San Juan

In San Juan in April humidity is 67%. With an average temperature of 21°C (70°F), this humidity feels like a warm embrace, making travel a bit stifling but still enjoyable if you're prepared with light clothing and plenty of water.

April Average Humidity in San Juan

This chart illustrates the average monthly humidity levels in San Juan, with April’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In April, average humidity in San Juan is approximately 67%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec68%68%66%67%69%84%85%82%81%80%80%73%
Data source: Humidity data for April generated using information from the Copernicus Climate Change Service.

April UV Index in San Juan

In San Juan in April, the maximum UV index reaches an alarming 15, which falls into the extreme Exposure Category. With a time to burn of just 10 minutes, it's crucial to take precautions. For detailed information, you can check the Hourly UV Index in San Juan.

Maximum UV Index Levels in San Juan for April

The chart shows the monthly maximum UV Index (UVI) for San Juan in April, 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 April, the maximum UV index in San Juan typically reaches 15, which falls under the extreme exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec121315151414141313141210
Data source: San Juan April 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 April 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 April’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 April’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
 TemperaturePrecipitationHumidityUV
January Weather20°C (68°F)32 mm (1.3 inches)68%extreme
February Weather20°C (69°F)13 mm (0.5 inches)68%extreme
March Weather21°C (70°F)15 mm (0.6 inches)66%extreme
April Weather21°C (70°F)79 mm (3.1 inches)67%extreme
May Weather21°C (70°F)391 mm (15.4 inches)69%extreme
June Weather21°C (70°F)351 mm (13.8 inches)84%extreme
July Weather21°C (69°F)233 mm (9.2 inches)85%extreme
August Weather20°C (69°F)331 mm (13.0 inches)82%extreme
September Weather20°C (69°F)436 mm (17.2 inches)81%extreme
October Weather20°C (68°F)570 mm (22.4 inches)80%extreme
November Weather20°C (68°F)209 mm (8.2 inches)80%extreme
December Weather20°C (68°F)63 mm (2.5 inches)72%very high

Compare San Juan's Climate with Cities Worldwide