September Weather in Siquirres, Costa Rica

Last updated: August 23, 2025

In September, the average temperature in Siquirres, Costa Rica is a pleasant 23°C (73°F), with daily fluctuations ranging from a minimum of 18°C (64°F) to a maximum of 29°C (85°F). Visitors can expect 176 mm (6.9 in) of precipitation spread over 27 days, contributing to an average humidity of 81%. Perfect for those who enjoy a tropical atmosphere!

September Temperature in Siquirres

In September in Siquirres, the average temperature is 23°C (73°F), with maximums reaching 29°C (85°F) and minimums dropping as low as 18°C (64°F). This makes it a perfect time for travelers to enjoy outdoor activities and explore the vibrant local culture.

September Weather in Siquirres: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Siquirres, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Siquirres, September typically has an average temperature of 23°C (73°F), with highs reaching up to 29°C (85°F) and lows dropping to around 18°C (64°F).

Data source: Temperature data for Siquirres generated using information from the Copernicus Climate Change Service.

September Precipitation in Siquirres

In Siquirres in September, the precipitation amount is 176 mm (6.9 in) over the course of 27 days.

September Precipitation Trends in Siquirres

The chart displays monthly precipitation patterns in Siquirres, with values for each month alongside September’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how September’s conditions compare to those of other months. In Siquirres, September typically receives around 176 mm (6.9 inches) of precipitation spread over approximately 27 days.

Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.

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Millimeters (mm) Inches (in)

September Humidity in Siquirres

In Siquirres in September, humidity is 81%. With an average temperature of 23°C (73°F), this humidity feels like a heavy blanket wrapping around you, making every step feel more laborious while traveling and causing you to constantly seek out shade or a cool breeze for relief.

September Average Humidity in Siquirres

This chart illustrates the average monthly humidity levels in Siquirres, with September’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In September, average humidity in Siquirres is approximately 81%, offering insight into how humid the weather typically is during this month.

Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Siquirres

In Siquirres in September, the maximum UV index is 14, which corresponds to an extreme Exposure Category. The time to burn is just 10 minutes, so it's crucial to take precautions. For the detailed hourly UV index in Siquirres, you can check here.

Maximum UV Index Levels in Siquirres for September

The chart shows the monthly maximum UV Index (UVI) for Siquirres in September, 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 September, the maximum UV index in Siquirres typically reaches 14, which falls under the extreme exposure category.

Data source: Siquirres September 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 September Weather in Siquirres Compares to Other Months

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

This table compares monthly weather conditions in Siquirres, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	20°C (69°F)	191 mm (7.5 inches)	68%	extreme
February Weather	20°C (69°F)	114 mm (4.5 inches)	68%	extreme
March Weather	21°C (69°F)	122 mm (4.8 inches)	66%	extreme
April Weather	22°C (72°F)	128 mm (5.0 inches)	67%	extreme
May Weather	23°C (73°F)	458 mm (18.0 inches)	69%	extreme
June Weather	23°C (73°F)	235 mm (9.3 inches)	84%	extreme
July Weather	22°C (73°F)	224 mm (8.8 inches)	85%	extreme
August Weather	23°C (73°F)	189 mm (7.4 inches)	82%	extreme
September Weather	23°C (73°F)	176 mm (6.9 inches)	81%	extreme
October Weather	23°C (73°F)	461 mm (18.1 inches)	80%	extreme
November Weather	22°C (72°F)	349 mm (13.7 inches)	80%	extreme
December Weather	21°C (70°F)	265 mm (10.4 inches)	72%	very high