December Weather in Alto, United States

Last updated: June 24, 2025

In December, the average temperature in Alto, United States hovers around 8°C (47°F). Expect a minimum of -7°C (20°F) and a maximum of 25°C (77°F), showcasing the range of weather you might encounter. With 146 mm (5.7 in) of precipitation over 11 days, staying dry may pose a challenge. Additionally, the average humidity level is a notable 88%, making the air feel quite humid.

December Temperature in Alto

In December in Alto, the average temperature is 8°C (47°F), with maximums reaching up to 25°C (77°F) and minimums dropping as low as -7°C (20°F). Be prepared for a wide range of temperatures during your travels, ensuring you pack accordingly for both warm and chilly conditions.

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

The chart illustrates December temperature patterns in Alto, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Alto, December typically has an average temperature of 8°C (47°F), with highs reaching up to 25°C (77°F) and lows dropping to around -7°C (20°F).

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

December Precipitation in Alto

In Alto in December, the precipitation amount is 146 mm (5.7 in) spread over 11 days.

December Precipitation Trends in Alto

The chart displays monthly precipitation patterns in Alto, 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 Alto, December typically receives around 146 mm (5.7 inches) of precipitation spread over approximately 11 days.

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

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Millimeters (mm) Inches (in)

December Humidity in Alto

In Alto in December, humidity is 88%. With an average temperature of 8°C (47°F), this humidity feels like a thick, damp blanket wrapping around you, making even short walks feel heavy and uninviting for travel.

December Average Humidity in Alto

This chart illustrates the average monthly humidity levels in Alto, 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 Alto is approximately 88%, 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 Alto

In Alto in December, the maximum UV index reaches 4, which corresponds to a moderate Exposure Category. With a time to burn of 30 minutes, it’s important to take precautions to protect your skin. You can find more details in the Hourly UV Index in Alto for better planning.

Maximum UV Index Levels in Alto for December

The chart shows the monthly maximum UV Index (UVI) for Alto 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 Alto typically reaches 4, which falls under the moderate exposure category.

Data source: Alto 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 Alto Compares to Other Months

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

This table compares monthly weather conditions in Alto, showing how December’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	7°C (44°F)	115 mm (4.5 inches)	86%	moderate
February Weather	9°C (49°F)	164 mm (6.5 inches)	86%	high
March Weather	12°C (54°F)	129 mm (5.1 inches)	86%	very high
April Weather	16°C (61°F)	130 mm (5.1 inches)	82%	extreme
May Weather	21°C (70°F)	132 mm (5.2 inches)	85%	extreme
June Weather	24°C (75°F)	112 mm (4.4 inches)	85%	extreme
July Weather	26°C (79°F)	102 mm (4.0 inches)	83%	extreme
August Weather	25°C (78°F)	135 mm (5.3 inches)	76%	very high
September Weather	23°C (74°F)	125 mm (4.9 inches)	76%	very high
October Weather	18°C (65°F)	168 mm (6.6 inches)	80%	very high
November Weather	11°C (52°F)	87 mm (3.4 inches)	88%	high
December Weather	8°C (47°F)	146 mm (5.7 inches)	88%	moderate