December Weather in Santiago, Mexico

Last updated: August 27, 2025

In December, the average temperature in Santiago, Mexico hovers around 18°C (65°F), creating a pleasant climate for outdoor activities. Expect a comfortable range, with minimum temperatures dipping to 8°C (46°F) and soaring up to 29°C (85°F). While you may experience brief showers, the total precipitation averages just 14 mm (0.5 in) over 1 day. Enjoy the mild weather alongside an average humidity of 69% for a refreshing experience!

December Temperature in Santiago

In December in Santiago, the average temperature is 18°C (65°F). Maximums can reach 29°C (85°F), while minimums can drop as low as 8°C (46°F). This pleasant range makes it an ideal time for travel, allowing for comfortable exploration and outdoor activities.

December Weather in Santiago: Daily Temperature Highs, Lows, and Averages

The chart illustrates December temperature patterns in Santiago, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Santiago, December typically has an average temperature of 18°C (65°F), with highs reaching up to 29°C (85°F) and lows dropping to around 8°C (46°F).

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

December Precipitation in Santiago

In Santiago in December, the precipitation amount is 14 mm (0.5 in) over the course of 1 day.

December Precipitation Trends in Santiago

The chart displays monthly precipitation patterns in Santiago, with values for each month alongside December’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how December’s conditions compare to those of other months. In Santiago, December typically receives around 14 mm (0.5 inches) of precipitation spread over approximately 1 days.

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

Choose your preferred precipitation unit

Millimeters (mm) Inches (in)

December Humidity in Santiago

In Santiago in December humidity is 69%. With an average temperature of 18°C (65°F), this humidity feels like a warm, damp blanket around you, making travel less comfortable and causing you to feel sticky and fatigued more quickly.

December Average Humidity in Santiago

This chart illustrates the average monthly humidity levels in Santiago, with December’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In December, average humidity in Santiago is approximately 69%, offering insight into how humid the weather typically is during this month.

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

December UV Index in Santiago

In Santiago in December, the maximum UV index is 6, which corresponds to a high Exposure Category. The time to burn is approximately 25 minutes. To find the hourly UV index in Santiago, you can refer to this Hourly UV Index in Santiago.

Maximum UV Index Levels in Santiago for December

The chart shows the monthly maximum UV Index (UVI) for Santiago in December, 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 December, the maximum UV index in Santiago typically reaches 6, which falls under the high exposure category.

Data source: Santiago December 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 December Weather in Santiago Compares to Other Months

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

This table compares monthly weather conditions in Santiago, showing how December’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	17°C (63°F)	10 mm (0.4 inches)	68%	high
February Weather	18°C (65°F)	14 mm (0.6 inches)	66%	very high
March Weather	20°C (69°F)	2 mm (0.1 inches)	65%	extreme
April Weather	23°C (73°F)	1 mm (0.0 inches)	63%	extreme
May Weather	25°C (77°F)	0 mm (0.0 inches)	63%	extreme
June Weather	28°C (83°F)	22 mm (0.9 inches)	66%	extreme
July Weather	28°C (84°F)	93 mm (3.7 inches)	71%	extreme
August Weather	28°C (83°F)	131 mm (5.2 inches)	73%	extreme
September Weather	26°C (80°F)	175 mm (6.9 inches)	74%	extreme
October Weather	25°C (78°F)	25 mm (1.0 inches)	73%	extreme
November Weather	22°C (72°F)	24 mm (0.9 inches)	71%	very high
December Weather	18°C (65°F)	14 mm (0.5 inches)	69%	high